SHAPING PARAMETRIC REGION AND MECHANICAL PROPERTIES OF SELECTIVE LASER SINTERING
OF NANO-Al²O³/POLYSTYRENE COMPOSITE

ZHENG Haizhong^{1, 2}  ZHANG Jian¹  XU Zhifeng¹

(1. School of Materials Science and Engineering, Nanchang Institute of Aeronautical Technology, Nanchang 330063;
2. School of Materials Science and Technology, Nanjing University of Aeronautics & Astronautic, Nanjing 210016)

Abstract: Based on the previous study in which laser power P and scan speed v have significant influences on the shaping performance of the powder NH1, the combined influences of laser power and scan speed are investigated. It is found that the physical density and strength of the specimens are little when P is low and v is fast; and smoke and warp distortion are observed when the specimens are sintered under high P and v speed; And the compact specimens with no warp distortion could be successfully fabricated under the appropriate combination of P and v which are in the proper forming shaping parametric region. The notched impact toughness of the sintered specimens is compared between the neat polystyrene powder and the power NH1 at the same process conditions. The result shows the notched impact toughness of nano-composite specimen is up to 10.5 kJ/m² and it is 20%～50% higher than that of the neat polystyrene specimen. The FE-SEM micrograph of the specimen’s section shows that the nano-particles disperse in matrix well and the polystyrene is toughened and strengthened because the polarity of nano-Al₂O₃ is modified by the nano-Al₂O₃/PS composite particles with core-shell.

Key words: Polymer matrix nanocomposite Selective laser sintering(SLS) Forming Shaping parametric region Notched impact strength

CLC No: TF12 TG430

江西省自然科学基金(0550098)、航空基金(20062756008)和江西省教育厅基金(2007-176)资助项目. Received 20060618, received in revised form 20070123