2002 Vol.15(Supplement)
Display Mode： |
2002, 16(Supplement).
Abstract:
Based on the geometrical features of the AFM (Atomic Force Microscope) diamond tip as well as the interaction existed between the diamond tip and the machined material, a theoretical model regarding single asperity cutting is put forward. The experiments are conducted on various materials including Al-alloy, single crystal germanium and silicon with different normal loads and cutting speed. On the basis of the theoretical analysis verified with the experimental results, a study of cutting process on nano-scale in terms of cutting force and various material removal mechanism is carried out.
Based on the geometrical features of the AFM (Atomic Force Microscope) diamond tip as well as the interaction existed between the diamond tip and the machined material, a theoretical model regarding single asperity cutting is put forward. The experiments are conducted on various materials including Al-alloy, single crystal germanium and silicon with different normal loads and cutting speed. On the basis of the theoretical analysis verified with the experimental results, a study of cutting process on nano-scale in terms of cutting force and various material removal mechanism is carried out.
2002, 16(Supplement).
Abstract:
Stress corrosion cracking (SCC) is one of the main corrosion failure modes of mechanical engineering materials. Techniques of SCC testing, electrochemical measurement and Auger electron spectroscopy (AES) analysis have been used to study SCC of 304 stainless steel (SS) in high temperature water and alloy 800 in hot caustic solution. The SCC susceptible potentials correspond to passive-transpassive (active) transition. Electrochemical polarization measurements of the alloys and pure metals are able to provide useful information on the correlation of activation-passivation of alloy to electrochemical behaviors of the main alloying elements in Fe-Cr-Ni alloys, which is also in good agreement with the re-sults of surface film analyses. It is concluded that combination of SCC tests, polarization curves and AES analyses is in-formative for better understanding the SCC mechanism of Fe-Cr-Ni alloys.
Stress corrosion cracking (SCC) is one of the main corrosion failure modes of mechanical engineering materials. Techniques of SCC testing, electrochemical measurement and Auger electron spectroscopy (AES) analysis have been used to study SCC of 304 stainless steel (SS) in high temperature water and alloy 800 in hot caustic solution. The SCC susceptible potentials correspond to passive-transpassive (active) transition. Electrochemical polarization measurements of the alloys and pure metals are able to provide useful information on the correlation of activation-passivation of alloy to electrochemical behaviors of the main alloying elements in Fe-Cr-Ni alloys, which is also in good agreement with the re-sults of surface film analyses. It is concluded that combination of SCC tests, polarization curves and AES analyses is in-formative for better understanding the SCC mechanism of Fe-Cr-Ni alloys.
2002, 16(Supplement).
Abstract:
Based on the thin shear zone analysis and the mechanics of cutting models for “sharp” tools, a predictive cutting force model for oblique machining allowing for the effect of tool flank wear is developed. An experimental study covering a wide range of process variables verifies the model and shows that the model prediction is in good agreement with the experiments.
Based on the thin shear zone analysis and the mechanics of cutting models for “sharp” tools, a predictive cutting force model for oblique machining allowing for the effect of tool flank wear is developed. An experimental study covering a wide range of process variables verifies the model and shows that the model prediction is in good agreement with the experiments.
2002, 16(Supplement).
Abstract:
An expert system of engineering component design and analysis based on fracture mechanics (FM) theory, AFES, is developed . It can simulate a human expert to make design and analysis scheme for several typical engineering components. Stress intensity factor K, crack opening displacement (COD) and J-integral criterions are used for assembled vats, pressure vessels, welding structures and rotation components：FATT criterion is used for heavy casting / forging components. The AFES consists of eight main functional parts：a general inference engine, a set of knowledge bases and data bases, an explanation model, an user interface model, a bases-administration system, a calculating model and an on-line help service. The AFES is an open system which may be broadened and perfected to cover a wider range of engineering application through modification and enlargement of the knowledge and data bases. The system may be a useful tool to assist a non-expert (with basic mechanics knowledge) make a quick access in engineering component design and analysis.
An expert system of engineering component design and analysis based on fracture mechanics (FM) theory, AFES, is developed . It can simulate a human expert to make design and analysis scheme for several typical engineering components. Stress intensity factor K, crack opening displacement (COD) and J-integral criterions are used for assembled vats, pressure vessels, welding structures and rotation components：FATT criterion is used for heavy casting / forging components. The AFES consists of eight main functional parts：a general inference engine, a set of knowledge bases and data bases, an explanation model, an user interface model, a bases-administration system, a calculating model and an on-line help service. The AFES is an open system which may be broadened and perfected to cover a wider range of engineering application through modification and enlargement of the knowledge and data bases. The system may be a useful tool to assist a non-expert (with basic mechanics knowledge) make a quick access in engineering component design and analysis.
2002, 16(Supplement).
Abstract:
An analysis of the kerf characteristics and technological cutting performance in contouring using an abrasive waterjet (AWJ) is presented. The analysis is based on an experimental investigation on an 87% alumina ceramic. Various plausible trends between the kerf characteristics and the process parameters are discussed. It is found that the kerf curvature has a considerable effect on the kerf geometrical accuracy and quality under different cutting conditions. Recommendations are made on selecting the cutting parameters to optimize the kerf quality.
An analysis of the kerf characteristics and technological cutting performance in contouring using an abrasive waterjet (AWJ) is presented. The analysis is based on an experimental investigation on an 87% alumina ceramic. Various plausible trends between the kerf characteristics and the process parameters are discussed. It is found that the kerf curvature has a considerable effect on the kerf geometrical accuracy and quality under different cutting conditions. Recommendations are made on selecting the cutting parameters to optimize the kerf quality.
2002, 16(Supplement).
Abstract:
Based on general theory of planetary transmission mechanism of elliptic gear, the output rotate angle equation of planetary elliptic gear is put forward by means of mathematical analytic method, and the effects of the different phases on the output rotate angles are obtained by the relationship curves, the results can be used when a new planetary elliptic gear train is designed.
Based on general theory of planetary transmission mechanism of elliptic gear, the output rotate angle equation of planetary elliptic gear is put forward by means of mathematical analytic method, and the effects of the different phases on the output rotate angles are obtained by the relationship curves, the results can be used when a new planetary elliptic gear train is designed.
2002, 16(Supplement).
Abstract:
Traditional ferrography only emphasizes on the characteristics of individual big debris. For diagnosing and monitoring the condition of machines, the traditional ferrography encounters trouble. Ferrography based on debris group theory thinks that there is a one-to-one correspondence between group characteristic of debris group and the operating condition. For this reason, the real wear condition will be deduced by studying the group characteristic of debris group in the ferrogram. By drawing out the criteria of the studied machine, the failure of the machine components will be predicted. Theoretical analysis and experimental research show that the operating condition predicted by debris group theory are consistent with the practical condition.
Traditional ferrography only emphasizes on the characteristics of individual big debris. For diagnosing and monitoring the condition of machines, the traditional ferrography encounters trouble. Ferrography based on debris group theory thinks that there is a one-to-one correspondence between group characteristic of debris group and the operating condition. For this reason, the real wear condition will be deduced by studying the group characteristic of debris group in the ferrogram. By drawing out the criteria of the studied machine, the failure of the machine components will be predicted. Theoretical analysis and experimental research show that the operating condition predicted by debris group theory are consistent with the practical condition.
2002, 16(Supplement).
Abstract:
The defects in the deep drawing usually are related to the blank shape. It is convenient and prompt to obtain an optimum blank shape using the computer simulation. An optimum blank shape is attained for a square cup deep drawing by using FEM-based code PAM-STAMP. The blank design method is illustrated by an example, a lampshade of cars.
The defects in the deep drawing usually are related to the blank shape. It is convenient and prompt to obtain an optimum blank shape using the computer simulation. An optimum blank shape is attained for a square cup deep drawing by using FEM-based code PAM-STAMP. The blank design method is illustrated by an example, a lampshade of cars.
2002, 16(Supplement).
Abstract:
Poor machinability of Al2O3 particle reinforced aluminum matrix composite (Al2O3p/Al) leads to severe tool wear with conventional mechanical machining methods and makes it difficult to ensure fine surface quality and efficiency. In order to solve this problem, laser-assisted hot machining method (LAHM) is adopted in this contribution to study the cutting of Al2O3p/Al. Good machining results are achieved by optimizing cutting and laser parameters, in which the cutting forces especially radial and axial forces are reduced by nearly 50%, tool wear is reduced by 30% and fine surface is attained. Detailed analysis and study are presented and a cutting process physical model is set up in this contribution which acts as theory fundamental of the research.
Poor machinability of Al2O3 particle reinforced aluminum matrix composite (Al2O3p/Al) leads to severe tool wear with conventional mechanical machining methods and makes it difficult to ensure fine surface quality and efficiency. In order to solve this problem, laser-assisted hot machining method (LAHM) is adopted in this contribution to study the cutting of Al2O3p/Al. Good machining results are achieved by optimizing cutting and laser parameters, in which the cutting forces especially radial and axial forces are reduced by nearly 50%, tool wear is reduced by 30% and fine surface is attained. Detailed analysis and study are presented and a cutting process physical model is set up in this contribution which acts as theory fundamental of the research.
2002, 16(Supplement).
Abstract:
The design and implementation of a proposed platform for collaborative design on the Internet are described. Such services are useful in design and manufacturing activities that would enable companies to plug in and participate through an information-sharing and communication architecture known as hub-and-spokes. This form of architecture has tremendous value as it has become increasingly evident that in the downstream stages of logistics, supply chain management and marketplace formation, the rise of exchanges in Business-to-Business commerce is tellingly indicative of the changing nature of economics of business collaboration. The proposed platform is one with potential of overcoming the tremendous amount of difficulties in enabling companies to collaborate in product development as current technologies in computer-aided design/manufacturing do not fully provide access to geometry and related non-geometric data. Demonstrative examples may be found in the capabilities to perform design and assembly modeling, as well as enable fixture design as a case scenario. Issues in furtherance of such a platform and its requisite performance and functionality criteria on the Internet are discussed and the future role of an application service provider model is proposed.
The design and implementation of a proposed platform for collaborative design on the Internet are described. Such services are useful in design and manufacturing activities that would enable companies to plug in and participate through an information-sharing and communication architecture known as hub-and-spokes. This form of architecture has tremendous value as it has become increasingly evident that in the downstream stages of logistics, supply chain management and marketplace formation, the rise of exchanges in Business-to-Business commerce is tellingly indicative of the changing nature of economics of business collaboration. The proposed platform is one with potential of overcoming the tremendous amount of difficulties in enabling companies to collaborate in product development as current technologies in computer-aided design/manufacturing do not fully provide access to geometry and related non-geometric data. Demonstrative examples may be found in the capabilities to perform design and assembly modeling, as well as enable fixture design as a case scenario. Issues in furtherance of such a platform and its requisite performance and functionality criteria on the Internet are discussed and the future role of an application service provider model is proposed.
2002, 16(Supplement).
Abstract:
When the flute of special rotary cutter with zero edge width is grinded, two adjacent cutting edges are generated simultaneously. A mathematical model for a five-axis NC machining of special rotary cutters with active control of the rake angle and the helical angle to ensure the correct cutting characteristics is proposed. The realization strategy of the modeling method and the correlative algorithm of computing cutter location are demonstrated.
When the flute of special rotary cutter with zero edge width is grinded, two adjacent cutting edges are generated simultaneously. A mathematical model for a five-axis NC machining of special rotary cutters with active control of the rake angle and the helical angle to ensure the correct cutting characteristics is proposed. The realization strategy of the modeling method and the correlative algorithm of computing cutter location are demonstrated.
2002, 16(Supplement).
Abstract:
Biomass is the potential energy that is the important renewable energy resources and chemical materials. The bioamass flash pyrolysis liquefaction technology is paid attention in this years. A new type small scale biomass pyrolysis liquefaction equipment is introduced and developed. In the light of analysis of mass balance and energy balance in the process of biomass pyrolysis, the design of the system that includes three parts of feeding, reaction, and production collection, is finished. The bio-oil is also produced in the test-run successfully. At the same time, the bio-oil component is analyzed by the GC-MS, that is helpful to the further research on the flash biomass pyrolysis process.
Biomass is the potential energy that is the important renewable energy resources and chemical materials. The bioamass flash pyrolysis liquefaction technology is paid attention in this years. A new type small scale biomass pyrolysis liquefaction equipment is introduced and developed. In the light of analysis of mass balance and energy balance in the process of biomass pyrolysis, the design of the system that includes three parts of feeding, reaction, and production collection, is finished. The bio-oil is also produced in the test-run successfully. At the same time, the bio-oil component is analyzed by the GC-MS, that is helpful to the further research on the flash biomass pyrolysis process.
2002, 16(Supplement).
Abstract:
The fatigue behavior is systematically investigated with three typical ceramic materials, including Y2O3-ZrO2, Si3N4 and a machinable glass-ceramic. Cyclic, static and dynamic fatigue tests are conducted in three environments, I.e., moist air, distilled water and kerosene. The effects of environment and loading condition on fatigue behavior are analyzed. The difference between materials is discussed. Experiment results show that, for all the three materials, fatigue life under cyclic load is the shortest and a small n value (fatigue exponent) is obtained. Compared with the other materials, Si3N4 ceramic has a very large n value under static load. Therefore the static fatigue for Si3N4 ceramics may be neglected. Cyclic load decreases the fatigue life of transformation-toughening ceramics(Y-TZP) more seriously, while no remarkable difference is observed between cyclic and static fatigue for original glass of the glass-ceramic. A new idea about the physical meaning of n value and the concept of intrinsic stress-corrosion exponent n0 is introduced. The n value could be divided into two terms, I.e., n=n0 + n?, where n? describes the contribution of microstructure toughening and is very sensitive to environ-ment and loading conditions. This theory could be used to describe and explain the experiment results successfully.
The fatigue behavior is systematically investigated with three typical ceramic materials, including Y2O3-ZrO2, Si3N4 and a machinable glass-ceramic. Cyclic, static and dynamic fatigue tests are conducted in three environments, I.e., moist air, distilled water and kerosene. The effects of environment and loading condition on fatigue behavior are analyzed. The difference between materials is discussed. Experiment results show that, for all the three materials, fatigue life under cyclic load is the shortest and a small n value (fatigue exponent) is obtained. Compared with the other materials, Si3N4 ceramic has a very large n value under static load. Therefore the static fatigue for Si3N4 ceramics may be neglected. Cyclic load decreases the fatigue life of transformation-toughening ceramics(Y-TZP) more seriously, while no remarkable difference is observed between cyclic and static fatigue for original glass of the glass-ceramic. A new idea about the physical meaning of n value and the concept of intrinsic stress-corrosion exponent n0 is introduced. The n value could be divided into two terms, I.e., n=n0 + n?, where n? describes the contribution of microstructure toughening and is very sensitive to environ-ment and loading conditions. This theory could be used to describe and explain the experiment results successfully.
2002, 16(Supplement).
Abstract:
Magnetorheological finishing (MRF) is a new optical machining technology. The mechanism of magnetorheological finishing is analyzed, the finishing experiment of optical glass of MRF is conducted through changing the finishing parameters such as relative speed of finishing disk and workpiece, magnetic field intensity, finishing duration, and the effect on the finishing character of optical glass by these parameters is analyzed on the basis of Preston equation. Measured by an AFM, the finished surface roughness of optical glass is Ra=1.015 nm. It's proved that MRF is an effective machining method to get high quality optical surface.
Magnetorheological finishing (MRF) is a new optical machining technology. The mechanism of magnetorheological finishing is analyzed, the finishing experiment of optical glass of MRF is conducted through changing the finishing parameters such as relative speed of finishing disk and workpiece, magnetic field intensity, finishing duration, and the effect on the finishing character of optical glass by these parameters is analyzed on the basis of Preston equation. Measured by an AFM, the finished surface roughness of optical glass is Ra=1.015 nm. It's proved that MRF is an effective machining method to get high quality optical surface.
2002, 16(Supplement).
Abstract:
The steel bonded carbide, a composite material, is very difficult to be machined to a fine finishing mirror surface. An electrolytic in-process dressing (ELID) grinding with metallic bond super-hard abrasive wheel is developed for grinding steel bonded carbide GT35. Factors effecting ELID grinding performance are analyzed by atomic force microscope (AFM). Based on the analysis of AFM topography of the fine ground mirror surface of the steel bonded carbide, a schematic diagram of the mechanism of micro-removal of the ground surface is described. The AFM topography also shows that the hard brittle carbide particles, on the surface of steel bonded carbide, are machined out by ductile cutting. The reason of producing grinding cracks in the grinding area is analyzed too. Experimental results indicate that a good mirror surface with Ra<0.02 μm can be obtained by the developed ELID grinding system.
The steel bonded carbide, a composite material, is very difficult to be machined to a fine finishing mirror surface. An electrolytic in-process dressing (ELID) grinding with metallic bond super-hard abrasive wheel is developed for grinding steel bonded carbide GT35. Factors effecting ELID grinding performance are analyzed by atomic force microscope (AFM). Based on the analysis of AFM topography of the fine ground mirror surface of the steel bonded carbide, a schematic diagram of the mechanism of micro-removal of the ground surface is described. The AFM topography also shows that the hard brittle carbide particles, on the surface of steel bonded carbide, are machined out by ductile cutting. The reason of producing grinding cracks in the grinding area is analyzed too. Experimental results indicate that a good mirror surface with Ra<0.02 μm can be obtained by the developed ELID grinding system.
2002, 16(Supplement).
Abstract:
The mechanical behavior of highly oriented pyrolytic graphite (HOPG) is investigated by simulating the micro-indentation with the method of molecular dynamics and by doing indent experiments with the probe tip of atomic force microscope. The characteristics of graphite crystal lattice are discussed, and according to that, three potentials are selected for different interaction between graphite atoms in molecular dynamic calculations. In experiment, nano-indentation test by tip and consequential measurement are carefully operated by AFM. The topography of the hole indented by the tip, as well the profile, the surface state of the graphite, the indented force and the strength of HOPG are measured and calculated. Results show the indentation experiment and the MD calculation consistent well with each other, that MD may be used as a good tool for comprehending the micro-mechanical behavior of a material.
The mechanical behavior of highly oriented pyrolytic graphite (HOPG) is investigated by simulating the micro-indentation with the method of molecular dynamics and by doing indent experiments with the probe tip of atomic force microscope. The characteristics of graphite crystal lattice are discussed, and according to that, three potentials are selected for different interaction between graphite atoms in molecular dynamic calculations. In experiment, nano-indentation test by tip and consequential measurement are carefully operated by AFM. The topography of the hole indented by the tip, as well the profile, the surface state of the graphite, the indented force and the strength of HOPG are measured and calculated. Results show the indentation experiment and the MD calculation consistent well with each other, that MD may be used as a good tool for comprehending the micro-mechanical behavior of a material.
2002, 16(Supplement).
Abstract:
Better and more capable tool materials allow machine tools to cut at increasingly higher speeds and feeds. In recent decades, high speed machining has received an important interest as a technological solution for high productivity to increase economic efficiency in manufacturing. The recent developments of cutting tool materials in high speed machining are reviewed. The appropriate applications of the high speed machining technology are presented. It can conclude that the optimal matching of mechanical, physical, and chemical properties between tool and workpiece materials is very important in high speed machining. The research is very great beneficial to the design and the selection of tool materials in high speed machining.
Better and more capable tool materials allow machine tools to cut at increasingly higher speeds and feeds. In recent decades, high speed machining has received an important interest as a technological solution for high productivity to increase economic efficiency in manufacturing. The recent developments of cutting tool materials in high speed machining are reviewed. The appropriate applications of the high speed machining technology are presented. It can conclude that the optimal matching of mechanical, physical, and chemical properties between tool and workpiece materials is very important in high speed machining. The research is very great beneficial to the design and the selection of tool materials in high speed machining.
2002, 16(Supplement).
Abstract:
The history of national and international research and development of piezoelectric dynamometers and the associated research carried out in the first author's group over 25 years are surveyed and presented. It mainly focuses on the applied fundamental theory of piezoelectric effects and the state-of-the-art achievements, such as the distribution of tangential sensitivity, the torsional effect of quartz crystals, and the models of physical effects on the transition between various forms of energy and so on. New product development of piezoelectric dynamometers within recent three years has been introduced including the YDXM-III97 type integral milling & grinding dynamometer, YDZ-II99 type drilling dynamometer without fixed rotating center, YDC-III2000 type three-dimensional small cutter arbor turning dynamometer used on numeric control machines. The relevant software and hardware for force-measuring system and the further research and development of piezoelectric dynamometers are presented.
The history of national and international research and development of piezoelectric dynamometers and the associated research carried out in the first author's group over 25 years are surveyed and presented. It mainly focuses on the applied fundamental theory of piezoelectric effects and the state-of-the-art achievements, such as the distribution of tangential sensitivity, the torsional effect of quartz crystals, and the models of physical effects on the transition between various forms of energy and so on. New product development of piezoelectric dynamometers within recent three years has been introduced including the YDXM-III97 type integral milling & grinding dynamometer, YDZ-II99 type drilling dynamometer without fixed rotating center, YDC-III2000 type three-dimensional small cutter arbor turning dynamometer used on numeric control machines. The relevant software and hardware for force-measuring system and the further research and development of piezoelectric dynamometers are presented.
2002, 16(Supplement).
Abstract:
The concept of rapid product development (RPD) has become an important aspect of integrated approach to reengineering and redesigning of industrial components. A methodology for the development of a reverse engineering (RE) technique is presented for use in the rapid product development in a CIM environment. The system developed provides integration, data capture and manipulation, data transfer between a CAD, CAM, computer-aided inspection (CAI) and a 3-D profile scanning system. An efficient multi-scanning strategy is developed for scanning and surfaces data acquisition. A mathematical surface model is used to develop a 3-D model of the product and final inspection is carried out using a CNC-CMM. The developed reverse engineering application in an integrated manufacturing system can increase the consistency, reduce production lead-time and skills required to redesign, reengineer and to reproduce components.
The concept of rapid product development (RPD) has become an important aspect of integrated approach to reengineering and redesigning of industrial components. A methodology for the development of a reverse engineering (RE) technique is presented for use in the rapid product development in a CIM environment. The system developed provides integration, data capture and manipulation, data transfer between a CAD, CAM, computer-aided inspection (CAI) and a 3-D profile scanning system. An efficient multi-scanning strategy is developed for scanning and surfaces data acquisition. A mathematical surface model is used to develop a 3-D model of the product and final inspection is carried out using a CNC-CMM. The developed reverse engineering application in an integrated manufacturing system can increase the consistency, reduce production lead-time and skills required to redesign, reengineer and to reproduce components.
2002, 16(Supplement).
Abstract:
The efficient machining of non-circular body of revolution requires a set of feed drive which actuates the tool-frame to make reciprocating motion. An innovative feed drive actuated by the stepper motor is introduced for the purpose. To eliminate quantitative error, the stepper motor is controlled under the continual mode. It is achieved with a micro-controller system and a built-in control algorithm program, called "tracking algorithm". Within each sampling cycle, the micro-controller will sample the input signal and the time interval will be divided into two parts according to the relative position between two adjacent stepping points. The phase coils correspondent to the two adjacent stepping points are energized respectively with calculated time duration. In this way, the motion of the tool frame smoothly tracks the input signal. The theoretical analysis and experimental study of frequency response of the proposed drive are presented. Experimental results show that the bandwidth of the feed drive system exceeds 310 Hz.
The efficient machining of non-circular body of revolution requires a set of feed drive which actuates the tool-frame to make reciprocating motion. An innovative feed drive actuated by the stepper motor is introduced for the purpose. To eliminate quantitative error, the stepper motor is controlled under the continual mode. It is achieved with a micro-controller system and a built-in control algorithm program, called "tracking algorithm". Within each sampling cycle, the micro-controller will sample the input signal and the time interval will be divided into two parts according to the relative position between two adjacent stepping points. The phase coils correspondent to the two adjacent stepping points are energized respectively with calculated time duration. In this way, the motion of the tool frame smoothly tracks the input signal. The theoretical analysis and experimental study of frequency response of the proposed drive are presented. Experimental results show that the bandwidth of the feed drive system exceeds 310 Hz.
2002, 16(Supplement).
Abstract:
Microwave heating technology is an alternative cost-effective way for assisting the thermosetting process of thin epoxy resin layers of material. With the benefit of existing modelling for computing the electromagnetic field and power density distribution in a cavity, an investigation is conducted about the application of the electromagnetic field and their effects on thin epoxy resin layer. The results of the simulations are used to optimise the design of the microwave heating system for curing thin epoxy resin layer. The investigation leads to a feasibility study to combine the microwave heating process with rapid product development technique, to efficiently build 3-dimensional models through fast curing of thin epoxy resin layers. Numerous configurations are investigated, by changing the design of microwave applicator. A numerical model is used to identify the strength and weakness of each design, leading to an optimised configuration that can be used for microwave heating, fast curing of thin epoxy resin layer. From the present study it can be concluded that a mathematical model can be used to optimise microwave heating devices, which can enable the configuration to deliver a uniform electric field.
Microwave heating technology is an alternative cost-effective way for assisting the thermosetting process of thin epoxy resin layers of material. With the benefit of existing modelling for computing the electromagnetic field and power density distribution in a cavity, an investigation is conducted about the application of the electromagnetic field and their effects on thin epoxy resin layer. The results of the simulations are used to optimise the design of the microwave heating system for curing thin epoxy resin layer. The investigation leads to a feasibility study to combine the microwave heating process with rapid product development technique, to efficiently build 3-dimensional models through fast curing of thin epoxy resin layers. Numerous configurations are investigated, by changing the design of microwave applicator. A numerical model is used to identify the strength and weakness of each design, leading to an optimised configuration that can be used for microwave heating, fast curing of thin epoxy resin layer. From the present study it can be concluded that a mathematical model can be used to optimise microwave heating devices, which can enable the configuration to deliver a uniform electric field.
2002, 16(Supplement).
Abstract:
The construction of a weldment surface from scattered data and extraction of welding seam is an important problem in welding robot stereovision system. The various methods on 3D surface reconstruction are reviewed at first, and according to weldment surface property, an autonomous, consecutive function approximation approach is presented to assign parameter values to obtained 3D points with noise for weldment surface by a least-square-fitting algorithm. Real range data are used to show the algorithm's performance and experimental results demonstrate the effectiveness of the proposed algorithm.
The construction of a weldment surface from scattered data and extraction of welding seam is an important problem in welding robot stereovision system. The various methods on 3D surface reconstruction are reviewed at first, and according to weldment surface property, an autonomous, consecutive function approximation approach is presented to assign parameter values to obtained 3D points with noise for weldment surface by a least-square-fitting algorithm. Real range data are used to show the algorithm's performance and experimental results demonstrate the effectiveness of the proposed algorithm.
2002, 16(Supplement).
Abstract:
A new cutting tool is introduced, which is used for manufacturing long metal fiber. It is charactered by its multi-tooth shape edge, which can manufacture several metal fibers simultaneously, therefore improve the productivity and the quality of metal fiber greatly, and develop the methods of manufacturing metal fiber enormously.
A new cutting tool is introduced, which is used for manufacturing long metal fiber. It is charactered by its multi-tooth shape edge, which can manufacture several metal fibers simultaneously, therefore improve the productivity and the quality of metal fiber greatly, and develop the methods of manufacturing metal fiber enormously.
2002, 16(Supplement).
Abstract:
The major discontinuous phenomena in the semisolid continuous casting process are the breakage and breakout. Through a theoretically analyzing on the crack filling and the unmoved shell developing, three continuity conditions of the process are established. The verifying experiments show that these conditions are reliable in applications, and may be used in the process and equipment design and the process control.
The major discontinuous phenomena in the semisolid continuous casting process are the breakage and breakout. Through a theoretically analyzing on the crack filling and the unmoved shell developing, three continuity conditions of the process are established. The verifying experiments show that these conditions are reliable in applications, and may be used in the process and equipment design and the process control.
2002, 16(Supplement).
Abstract:
A new idea of competitive advantage is elucidated and it is put forward that the new competitive capability for future manufacturing enterprises which is fast reorganizing the manufacturing resource concerning the developing environment and state of manufacturing industry in China. The implement mode and methods are discussed and elucidated by means of economic mode. Distributed networking manufacturing (DNM) and Group-based mass-customization (GMS) are putting forward by our team's program and some progress is made and introduced in briefly.
A new idea of competitive advantage is elucidated and it is put forward that the new competitive capability for future manufacturing enterprises which is fast reorganizing the manufacturing resource concerning the developing environment and state of manufacturing industry in China. The implement mode and methods are discussed and elucidated by means of economic mode. Distributed networking manufacturing (DNM) and Group-based mass-customization (GMS) are putting forward by our team's program and some progress is made and introduced in briefly.
2002, 16(Supplement).
Abstract:
Spray metal tooling is a rapid tooling process, which allows rapid fabrication of moulds for a variety of different manufacturing processes especially injection moulding. An investigation is presented on development of direct spray metal tooling for injection moulding using the fused deposition modelling (FDM) rapid prototyping process. The material used to spray is zinc alloy, which serves as the protective coating for the nylon insert made directly on the FDM process. This study focuses on this new technique and the plastic parts produced by the zinc coated nylon insert on the injection-moulding machine.
Spray metal tooling is a rapid tooling process, which allows rapid fabrication of moulds for a variety of different manufacturing processes especially injection moulding. An investigation is presented on development of direct spray metal tooling for injection moulding using the fused deposition modelling (FDM) rapid prototyping process. The material used to spray is zinc alloy, which serves as the protective coating for the nylon insert made directly on the FDM process. This study focuses on this new technique and the plastic parts produced by the zinc coated nylon insert on the injection-moulding machine.
2002, 16(Supplement).
Abstract:
A novel hybrid machine tool is introduced. It is with parallel and serial structures, which is based on a new 2-DOF parallel platform and serial orientations. The kinematic analysis and Newton-Euler equations of the parallel structure and the serial structure are presented respectively. Then Newton-Euler equations of the novel hybrid machine tool are derived. These results are believed to be useful in studying dynamics and control of this hybrid machine.
A novel hybrid machine tool is introduced. It is with parallel and serial structures, which is based on a new 2-DOF parallel platform and serial orientations. The kinematic analysis and Newton-Euler equations of the parallel structure and the serial structure are presented respectively. Then Newton-Euler equations of the novel hybrid machine tool are derived. These results are believed to be useful in studying dynamics and control of this hybrid machine.
2002, 16(Supplement).
Abstract:
The microstructure and morphology as well as the bonding fracture of coating-sand interface are investigated by using sweeping electron microscope (SEM) and electronic probe analyzer (EPA) methods. According to the analysis results, an intermediate layer of resin is proposed as a measure to enhance stress CS. The results show that it can raise the bonding ratio and ideal strength therefore increase stress CS significantly. Fracture analysis shows that the bonding destruction happen inside the intermediate layer, therefore chemical cross-linking agents such as glycerin are used to enhance the cohesive strength of the polyacrylic acid intermediate layer. Consequently, stress CS get a further growth.
The microstructure and morphology as well as the bonding fracture of coating-sand interface are investigated by using sweeping electron microscope (SEM) and electronic probe analyzer (EPA) methods. According to the analysis results, an intermediate layer of resin is proposed as a measure to enhance stress CS. The results show that it can raise the bonding ratio and ideal strength therefore increase stress CS significantly. Fracture analysis shows that the bonding destruction happen inside the intermediate layer, therefore chemical cross-linking agents such as glycerin are used to enhance the cohesive strength of the polyacrylic acid intermediate layer. Consequently, stress CS get a further growth.
2002, 16(Supplement).
Abstract:
In order to investigate the cutting performance of the plane face ball end milling cutter, the numerical simulation study is done by means of the predictive cutting model and software module for the forces, torque and power under different conditions. The simulating study could not only improve the predicting model, but also understand the fluctuation trends and magnitudes of force components and torque under main process variables. Meanwhile, the characters and trends of the force components and torque on the fluctuation pattern and magnitude of the maximum, minimum and average are investigated in detail. This work can assist in improving the design of ball end milling cutters, the design of machine tool components, the optimization of cutting operations, the monitoring and controlling of cutting process parameters.
In order to investigate the cutting performance of the plane face ball end milling cutter, the numerical simulation study is done by means of the predictive cutting model and software module for the forces, torque and power under different conditions. The simulating study could not only improve the predicting model, but also understand the fluctuation trends and magnitudes of force components and torque under main process variables. Meanwhile, the characters and trends of the force components and torque on the fluctuation pattern and magnitude of the maximum, minimum and average are investigated in detail. This work can assist in improving the design of ball end milling cutters, the design of machine tool components, the optimization of cutting operations, the monitoring and controlling of cutting process parameters.
2002, 16(Supplement).
Abstract:
In micro milling process, predicting the life of micro grain carbide cutter is quite tedious and cumbersome because of the size, dimension and unpredictable nature of tool failure. An empirical model is presented using a second order equation for predicting the tool life of micro and mill cutter under dry cutting condition. The model is developed covering wide ranges of primary variables such as cutting speed, feed rate and axial depth of cut by optimizing the response to maximize the tool life. The model presented is adequate for a 95% of confidence interval, and shows good correlation between experimental and predicted results.
In micro milling process, predicting the life of micro grain carbide cutter is quite tedious and cumbersome because of the size, dimension and unpredictable nature of tool failure. An empirical model is presented using a second order equation for predicting the tool life of micro and mill cutter under dry cutting condition. The model is developed covering wide ranges of primary variables such as cutting speed, feed rate and axial depth of cut by optimizing the response to maximize the tool life. The model presented is adequate for a 95% of confidence interval, and shows good correlation between experimental and predicted results.
2002, 16(Supplement).
Abstract:
With stereovision principle, a real time detecting technique for workpiece is proposed, and the principle and method of the detection technique are expounded in detail. First, workpiece edge is detected by wavelet transform. Second, using geometric invariance, corresponding points are searched. Last, workpiece size is detected, workpiece shape is recognized, and workpiece is detected on line. The experiments show that detection deviation is less than 0.2 mm and detection time is less than 4 s.
With stereovision principle, a real time detecting technique for workpiece is proposed, and the principle and method of the detection technique are expounded in detail. First, workpiece edge is detected by wavelet transform. Second, using geometric invariance, corresponding points are searched. Last, workpiece size is detected, workpiece shape is recognized, and workpiece is detected on line. The experiments show that detection deviation is less than 0.2 mm and detection time is less than 4 s.
2002, 16(Supplement).
Abstract:
Virtual die tryout (VDT) technology is a powerful tool for sheet metal forming, compared with the traditional die tryout process. The FEM in the elasto-plastic problems is a basis of this technology. VDT technology and its application in sheet metal forming are described. The FEM program used in this research is the PAM-STAMP.
Virtual die tryout (VDT) technology is a powerful tool for sheet metal forming, compared with the traditional die tryout process. The FEM in the elasto-plastic problems is a basis of this technology. VDT technology and its application in sheet metal forming are described. The FEM program used in this research is the PAM-STAMP.
2002, 16(Supplement).
Abstract:
The crystalline size of both the titanium and the aluminum phase becomes finer and finer, and finally nanocrystalline and amorphous Ti/Al composite powders are formed by mechanical milling of the Ti and Al elemental powder mixture. However, no titanium aluminides are observed in the as-above milled powders. Differential thermal analysis (DTA) tests show that the composite powders prepared by mechanical milling for various times retain different internal energy. The longer the milling time, the more the stored internal energy within the milled powders, with the amorphous composite powders possessing the most internal energy, which can be attributed to the fact that the lattice defects due to mechanical milling increase significantly with prolonged milling time. Isothermal vacuum annealing treatments of the Ti/Al composite powders milled for various hours show that the longer the milling time, the greater the possibility for the solid state reaction between the constituent Ti and Al element to form titanium aluminides within the composite powders during annealing. For the nanocrystalline or amorphous composite powders mechanically milled no less than 75 h, the full titanium aluminides microstructure can be formed by 1 h annealing even at such a low temperature as 450 ℃.
The crystalline size of both the titanium and the aluminum phase becomes finer and finer, and finally nanocrystalline and amorphous Ti/Al composite powders are formed by mechanical milling of the Ti and Al elemental powder mixture. However, no titanium aluminides are observed in the as-above milled powders. Differential thermal analysis (DTA) tests show that the composite powders prepared by mechanical milling for various times retain different internal energy. The longer the milling time, the more the stored internal energy within the milled powders, with the amorphous composite powders possessing the most internal energy, which can be attributed to the fact that the lattice defects due to mechanical milling increase significantly with prolonged milling time. Isothermal vacuum annealing treatments of the Ti/Al composite powders milled for various hours show that the longer the milling time, the greater the possibility for the solid state reaction between the constituent Ti and Al element to form titanium aluminides within the composite powders during annealing. For the nanocrystalline or amorphous composite powders mechanically milled no less than 75 h, the full titanium aluminides microstructure can be formed by 1 h annealing even at such a low temperature as 450 ℃.
2002, 16(Supplement).
Abstract:
Titanium alloy is one of the most difficult-to-cut materials. High-speed machining of Ti-6Al-4V is discussed from the viewpoint of cutting temperature and tool wear. In turning, the heat generated should be dissipated as quickly as possible because the cutting temperature is considerably high. The tool material which has high thermal conductivity, such as natural diamond tool, is suitable for high speed turning under the wet condition. However, the cutting temperature in high speed milling with a small diameter end mill is found to be considerably low. The milling of Ti-6Al-4V at the cutting speed 283 m/min is achieved even under dry condition because of this low cutting temperature. Supplying oil mist coolant is more effective to prolong the tool life in high speed milling.
Titanium alloy is one of the most difficult-to-cut materials. High-speed machining of Ti-6Al-4V is discussed from the viewpoint of cutting temperature and tool wear. In turning, the heat generated should be dissipated as quickly as possible because the cutting temperature is considerably high. The tool material which has high thermal conductivity, such as natural diamond tool, is suitable for high speed turning under the wet condition. However, the cutting temperature in high speed milling with a small diameter end mill is found to be considerably low. The milling of Ti-6Al-4V at the cutting speed 283 m/min is achieved even under dry condition because of this low cutting temperature. Supplying oil mist coolant is more effective to prolong the tool life in high speed milling.
2002, 16(Supplement).
Abstract:
In high speed machining of difficult-to-cut materials such as high temperature alloy, titanium alloy, stainless steel and so on, the chip deforms in pattern of shear localization which is different from continuous chip entirely. In this case, the chip deformation is concentrated in the narrow shear band and most part of the chip segment is formed under relative low strain. The basic model of cutting process is the cutting equation. Considering the critical condition of plastic instability and based on the minimum energy principle, the cutting equation for the shear localization pattern is established.
In high speed machining of difficult-to-cut materials such as high temperature alloy, titanium alloy, stainless steel and so on, the chip deforms in pattern of shear localization which is different from continuous chip entirely. In this case, the chip deformation is concentrated in the narrow shear band and most part of the chip segment is formed under relative low strain. The basic model of cutting process is the cutting equation. Considering the critical condition of plastic instability and based on the minimum energy principle, the cutting equation for the shear localization pattern is established.
2002, 16(Supplement).
Abstract:
Virtual machine tools(VMT) technology is one of the main enabling technologies of virtual manufacturing technology and is paid great attention to by researchers throughout world. Based on it's foundational function, virtual machine tools and it's architecture are investigated and a modeling method of virtual machine tools is proposed. It's key technologies such as NC program translator, NC program checking technology, tool library management, VRML based CAD interface, and stock discretization and cutting simulation etc are researched.
Virtual machine tools(VMT) technology is one of the main enabling technologies of virtual manufacturing technology and is paid great attention to by researchers throughout world. Based on it's foundational function, virtual machine tools and it's architecture are investigated and a modeling method of virtual machine tools is proposed. It's key technologies such as NC program translator, NC program checking technology, tool library management, VRML based CAD interface, and stock discretization and cutting simulation etc are researched.
2002, 16(Supplement).
Abstract:
As an enabling technology or system integration framework, product data management (PDM) can manage the product-related information and process during the life cycle of manufacturing product in the range of whole enterprise. With the development of computer and network, PDM is applied in more enterprises. By studying the framework of PDM based on Intranet/Internet, this paper analyses the limitation of current PDM application software in security, proposes the method to build PDM security system, and discusses deeply how to keep security of data and process in PDM system. Some tools or methods about identity authentication, data encryption, digital signature, etc, which are used in PDM system, are described.
As an enabling technology or system integration framework, product data management (PDM) can manage the product-related information and process during the life cycle of manufacturing product in the range of whole enterprise. With the development of computer and network, PDM is applied in more enterprises. By studying the framework of PDM based on Intranet/Internet, this paper analyses the limitation of current PDM application software in security, proposes the method to build PDM security system, and discusses deeply how to keep security of data and process in PDM system. Some tools or methods about identity authentication, data encryption, digital signature, etc, which are used in PDM system, are described.
2002, 16(Supplement).
Abstract:
It is impossible to avoid the link interference of the 6-SPS PKM (parallel kinematic machine tool) by using the hardware and it is also very hard to check it by using the software real-timely nowadays. However, link interference is a serious potential safety problem. A workspace model of XNZ63 based on the concerns about the journey of links, the geography restriction of hinges, the link interference and the pose restriction of the moving platform are established. The solution set of the model, whose envelope is a closed planar line, is found out by using the numerical continuous method, and this envelope describes the relationship of the tool's rotation angle about its own axis and the link interference directly. A range of the tool's rotation angle, which is restricted by the controllable extra freedom, is obtained by analyzing the characteristics of the envelope, and the link interference is sure not to happen with the restriction of this angle.
It is impossible to avoid the link interference of the 6-SPS PKM (parallel kinematic machine tool) by using the hardware and it is also very hard to check it by using the software real-timely nowadays. However, link interference is a serious potential safety problem. A workspace model of XNZ63 based on the concerns about the journey of links, the geography restriction of hinges, the link interference and the pose restriction of the moving platform are established. The solution set of the model, whose envelope is a closed planar line, is found out by using the numerical continuous method, and this envelope describes the relationship of the tool's rotation angle about its own axis and the link interference directly. A range of the tool's rotation angle, which is restricted by the controllable extra freedom, is obtained by analyzing the characteristics of the envelope, and the link interference is sure not to happen with the restriction of this angle.
2002, 16(Supplement).
Abstract:
Space environments, such as wall, ceiling and ladder, are important application field for legged robot. Therefore, a new five-legged robot prototype in the function bionics is developed to move in various environments. The motion plan to climb ladder is studied for the robot. According to the structure of the five-legged robot and the force distribution which is produced in the course of climbing ladder, the climbing-ladder motion is analyzed, a practical pentapodal climbing gait is proposed. The climbing motion on the ladders with equal or unequal interval poles is palnned and modeled with determining the motion conditions. The simulations and the experiments in the typical climbing environments are presented. The results confirm that the kinematics analysis and algorithm are correct and feasible.
Space environments, such as wall, ceiling and ladder, are important application field for legged robot. Therefore, a new five-legged robot prototype in the function bionics is developed to move in various environments. The motion plan to climb ladder is studied for the robot. According to the structure of the five-legged robot and the force distribution which is produced in the course of climbing ladder, the climbing-ladder motion is analyzed, a practical pentapodal climbing gait is proposed. The climbing motion on the ladders with equal or unequal interval poles is palnned and modeled with determining the motion conditions. The simulations and the experiments in the typical climbing environments are presented. The results confirm that the kinematics analysis and algorithm are correct and feasible.
2002, 16(Supplement).
Abstract:
By drying cutting experiments of cutting forces, cutting temperature, and the integrity of machined surface of bearing steel GCr15 which is machined by PCBN tools, the effect law of the workpiece hardness on above-mentioned variables and chip shape, chip hardness, chip deformation coefficient is obtained. The workpiece critical hardness between general cutting and hard cutting is found, and it is 50 HRC for GCr15.
By drying cutting experiments of cutting forces, cutting temperature, and the integrity of machined surface of bearing steel GCr15 which is machined by PCBN tools, the effect law of the workpiece hardness on above-mentioned variables and chip shape, chip hardness, chip deformation coefficient is obtained. The workpiece critical hardness between general cutting and hard cutting is found, and it is 50 HRC for GCr15.
2002, 16(Supplement).
Abstract:
A laminated removal electrical discharge milling(LRED-milling) method is presented which combines the concept of laminated machining in rapid prototyping and the electrode uniform wear in EDM. The basic principle of laminated removal ED-milling is using simply shaped electrodes to remove the material from the workpiece layer by layer along with predetermined paths. By using this method, the time and cost of preparation on electrodes with complex surfaces can be dramatically eliminated. As an example, a simplified mold of IC socket with 40 pins is machined by LRED-milling. The result shows that this method is suitable for rapid mold making or rapid tooling. It expectably achieves better machining accuracy with much less expense, and it shows great potential of application in the future.
A laminated removal electrical discharge milling(LRED-milling) method is presented which combines the concept of laminated machining in rapid prototyping and the electrode uniform wear in EDM. The basic principle of laminated removal ED-milling is using simply shaped electrodes to remove the material from the workpiece layer by layer along with predetermined paths. By using this method, the time and cost of preparation on electrodes with complex surfaces can be dramatically eliminated. As an example, a simplified mold of IC socket with 40 pins is machined by LRED-milling. The result shows that this method is suitable for rapid mold making or rapid tooling. It expectably achieves better machining accuracy with much less expense, and it shows great potential of application in the future.
2002, 16(Supplement).
Abstract:
Computer aided design (CAD) mainly focuses on drawing function for engineers in this time and hasn't enough field knowledge to improve design efficiency. A new concept of knowledge-based engineering (KBE) is presented. Its key technologies (knowledge representation, reasoning and acquirement), such as frame-rule representation and reasoning, case-based reasoning and neural network reasoning, are studied. This system structure has two advantages: ① Multi-methods of knowledge representation are integrated and can express knowledge of many fields. ② Knowledge acquirement is introduced into engineering design system and improves its learning ability and adaptability. Integrated with this system, general CAD systems can be improved into computer-aided design from computer-aided drawing. Having researched the process of designing mold base, a knowledge-based system is developed for mold base design who can apparently improve design efficiency in practice.
Computer aided design (CAD) mainly focuses on drawing function for engineers in this time and hasn't enough field knowledge to improve design efficiency. A new concept of knowledge-based engineering (KBE) is presented. Its key technologies (knowledge representation, reasoning and acquirement), such as frame-rule representation and reasoning, case-based reasoning and neural network reasoning, are studied. This system structure has two advantages: ① Multi-methods of knowledge representation are integrated and can express knowledge of many fields. ② Knowledge acquirement is introduced into engineering design system and improves its learning ability and adaptability. Integrated with this system, general CAD systems can be improved into computer-aided design from computer-aided drawing. Having researched the process of designing mold base, a knowledge-based system is developed for mold base design who can apparently improve design efficiency in practice.
2002, 16(Supplement).
Abstract:
According to distortion of the circular saw blade that is determined by microcomputer checking system stress analysis model is built up. The calculated stress value is employed as load for prestressing in tension of the circular saw blades. The stress analysis model is built up according to the hypothesis of Kirchhof. The examine of the calculated stress value is obtained from experiments and practice in factory of machining circular saw blades. The new technique on the calculated stress value is put into operation of the prestressing in tension for circular saw blades and can achieve controllability in time.
According to distortion of the circular saw blade that is determined by microcomputer checking system stress analysis model is built up. The calculated stress value is employed as load for prestressing in tension of the circular saw blades. The stress analysis model is built up according to the hypothesis of Kirchhof. The examine of the calculated stress value is obtained from experiments and practice in factory of machining circular saw blades. The new technique on the calculated stress value is put into operation of the prestressing in tension for circular saw blades and can achieve controllability in time.
2002, 16(Supplement).
Abstract:
A new kind of zirconia matrix ceramic material (ZrO2/Al2O3) is developed with 3Y-PSZ(3% Y2O3 partially stabilized ZrO2) and the additive of alumina. The wear resistance of ZYA20 (3Y-PSZ+20% Al2O3) is experimentally investigated comparing with ZYA30 (3Y-PSZ+30% Al2O3) by the wear ring-block test. It is shown that the friction coefficients of ZYA20 and ZYA30 decrease with the increment of the applied load and the wear ratios increase with the increment of the applied load. It is also found that their wear mechanisms are plastic deformation, adhesive and abrasive wear as well as stripping. The wear resistance of ZYA20 and ZYA30 is very good at low load and the former is stronger than the latter.
A new kind of zirconia matrix ceramic material (ZrO2/Al2O3) is developed with 3Y-PSZ(3% Y2O3 partially stabilized ZrO2) and the additive of alumina. The wear resistance of ZYA20 (3Y-PSZ+20% Al2O3) is experimentally investigated comparing with ZYA30 (3Y-PSZ+30% Al2O3) by the wear ring-block test. It is shown that the friction coefficients of ZYA20 and ZYA30 decrease with the increment of the applied load and the wear ratios increase with the increment of the applied load. It is also found that their wear mechanisms are plastic deformation, adhesive and abrasive wear as well as stripping. The wear resistance of ZYA20 and ZYA30 is very good at low load and the former is stronger than the latter.
2002, 16(Supplement).
Abstract:
To achieve both efficiency of mass production and flexibility of job shop or batch production, "virtual cellular manufacturing"(VCM) is shown possible by past research. VCM views cells as temporary and virtual entities. A preliminary investigation is done to push and pull control paradigms for VCM using a stochastic Petri nets (SPN) approach. The result of the study shows that, under conventional assumptions, pull system is better in controlling of work-in-process (WIP) while push system improves utilisation.
To achieve both efficiency of mass production and flexibility of job shop or batch production, "virtual cellular manufacturing"(VCM) is shown possible by past research. VCM views cells as temporary and virtual entities. A preliminary investigation is done to push and pull control paradigms for VCM using a stochastic Petri nets (SPN) approach. The result of the study shows that, under conventional assumptions, pull system is better in controlling of work-in-process (WIP) while push system improves utilisation.
2002, 16(Supplement).
Abstract:
In the conventional method for design and production in jewellery industry, it is difficult to create new designs due to lack of modern technology and intelligent equipment and software. The development of a jewellery design system is presented for a modern ornament industry by adopting new technologies and modern equipment in CAD/CAM. The technique is verified by the examples of actual jewellery design by the system and then producing it by lost wax investment casting method using wax pattern created by a rapid prototyping system instead of the traditional method of mould injection. This CAD based system of development of modern jewellery design offers advantages of flexibility in creating more variety of design and the ability to produce intricate shape conveniently. The work demonstrates the application of CAD/CAM tools and rapid prototyping as the most powerful tools in jewellery design and production.
In the conventional method for design and production in jewellery industry, it is difficult to create new designs due to lack of modern technology and intelligent equipment and software. The development of a jewellery design system is presented for a modern ornament industry by adopting new technologies and modern equipment in CAD/CAM. The technique is verified by the examples of actual jewellery design by the system and then producing it by lost wax investment casting method using wax pattern created by a rapid prototyping system instead of the traditional method of mould injection. This CAD based system of development of modern jewellery design offers advantages of flexibility in creating more variety of design and the ability to produce intricate shape conveniently. The work demonstrates the application of CAD/CAM tools and rapid prototyping as the most powerful tools in jewellery design and production.
E-mail Alerts
