STRESS ANALYSIS AND FGM MODELS DESIGN OF ABRASIVE JET MACHINING NOZZLE

LIU Lili^{1, 2}  DENG Jianxin¹  DING Mingwei¹

(1. School of Mechanical Engineering, Shandong University, Jinan 250061；
2. School of Mechanical and Electrical Engineering, Pingyuan University, Xinxiang 453003 )

Abstract: The stress states of the nozzle in abrasive jet machining (AJM) process are analyzed. Results show that the maximum stress appears in entrance area of the nozzle and minimum stress in middle area, while the stress of exit area is lower than entrance area and higher than middle area. Blasting results reveal that the nozzle entry region always suffers form severe abrasive impact, and generates large tensile stress, which leads to an increased erosion wear at the nozzle entry area. The idea of functionally gradient material (FGM) theory is used to design ceramic nozzle. The design of composition distribution of the gradient ceramic nozzle is carried out with the aim of partial relaxation of the stress resulting from external loadings by residual thermal stress. Based on the design results, a SiC/(W,Ti)C gradient ceramic nozzle is produced. The erosion behavior of the SiC/(W,Ti)C gradient ceramic nozzle is investi-gated in comparison with the common ceramic nozzles. Results show that the SiC/(W,Ti)C gradient ceramic nozzles exhibit an apparent increase in erosion wear resistance over the common ceramic nozzles under the same test conditions.

Key words: Ceramic nozzle Stress analysis Erosion wear Function gradient material Residual stress

CLC No: TQ174

高等学校博士学科点专项科研基金(20030422015)、山东省自然科学基金(Y2004F08)和新世纪优秀人才支持计划(NCET-04-0622)资助项目. Received 20051027, received in revised form 20051230