Effect Of SiC Particle Size Research Articles

ＳｉＣ粒子強化アルミニウム合金基複合材料の被削性

Aluminum alloy matrix composite materials are expected to be used for various applications because of the low density and superior properties at high temperatures. However, the composite materials give problems in the tool wear because of their difficulty in cutting. In this work the turning test for SiC particle reinforced aluminum alloy composite materials was performed and the effects of SiC particle size and content on the tool wear and surface roughness were discussed. The tool wear increased with increasing SiC particle size and content. Only the diamond tool was useful to cut the SiC particle reinforced aluminum alloy composite material. In the case of using a carbide tool, the cutting condition should be low cutting speed as well as high feed rate. To suck the chips during cutting was effective to decrease the tool wear. In the wet cutting, however, to suck the chips resulted in the increased tool wear. While the increased SiC particle size resulted in the worsened surface roughness, the increased SiC content improved the surface roughness.

Mechanical properties of AlSiC composites made by resistance sintering of mechanically alloyed powders

This work has demonstrated the potential of making high strength AlSiC composites with reasonable ductility by resistance sintering of mechanically alloyed powders. The effects of SiC particle size and content on the mechanical properties of SiC-particulate-reinforced aluminium composites were systematically studied by the use of compressive tests. It was found that the compressive yield stress and ultimate strength increases with increasing SiC volume fraction and decreasing SiC particle size, while the compressive failure strain shows the reverse trend with the variation in SiC particle size and content. The high strength of the resistance-sintered AlSiC composites may be attributed to the fine subgrain structure in the aluminium matrix, the dislocations generated by differential contraction of aluminium and SiC particulates, and the previous worked structure in the aluminium matrix resulted from the mechanical alloying process. In addition, it was suggested that, besides the formation of liquid phase, the plastic deformation of AlSiC composite powders also makes a contribution to the densification process in resistance sintering.