铜石墨粉末冶金受电靴材料工艺及微观结构

Processing and Microstructures of Copper-graphite Collector Shoe Material Produced by Powder Metallurgy

用粉末冶金方法,将铜、石墨、铬、锡、铅粉末机械混合,制备磁浮轨道交通受电靴滑块所需的铜石墨材料。在300MPa的压力下常温压制成形,之后在氢气保护气氛下分别在880℃×1h和920℃×2h烧结,冷却至室温后,再以300MPa的压力进行复压。结果表明,适当提高材料的烧结温度和烧结时间,可提高材料的力学性能。拉伸断裂以脆性断裂为主,包含着局部的韧性断裂。基体中存在的位错、层错和孪晶有益于材料的力学性能。

A type of copper-graphite collector shoe material was made by means of the pov der metallurgy route for maglev. The mixtures of the investigated powders are sintered with processes of 880°C × 1h and 920°C × 2h in compacted with 300MPa at ambient temperature, and hydrogen atmosphere, respectively. After specimens are cooled to room temperature with the furnace, repression is operated at 300MPa. The mechanical properties of the copper-graphite composite are increased with the increase of the sintering temperature and sintering time in some extent. The tensile failure is mainly brittle fracture, whose part is toughness fracture. Dislocations, faults and twins in metallic matrix are advantageous to mechanical property of the materials.