微/纳米双尺度混杂颗粒增强铝基复合材料的制备工艺

采用粉末真空热压烧结机,将微米尺度的SiC颗粒、Al-Si合金基体粉末与反应剂CuO粉末混合后加热到一定温度,使CuO与Al发生原位反应,生成纳米尺度的Al2O3颗粒,然后冷却、热压,制得(微米SiC+纳米Al2O3)/Al-Si双尺度混杂颗粒增强铝基复合材料,并对复合材料进行热处理强化。研究了不同的原位反应加热温度、热压温度、热压压力对复合材料组织、硬度及磨损性能的影响。结果表明,采用微米SiC及纳米Al2O3混杂颗粒强化、热压强化、热处理强化等强化后制备的铝基复合材料具有较高的硬度及耐磨性。原位反应加热温度为620℃、热压温度510℃、热压压力3MPa时,复合材料试样组织细小致密,硬度及耐磨性最好,复合材料的磨损机制主要为磨粒磨损。

Research Progress of Hybrid Particle Reinforced Aluminum Matrix Composites

Micron sized SiC particles and Al-Si alloy matrix powder were mixed with reactive agent CuO powder in a vacuum hot-pressing sintering machine, and then heated to a certain temperature to make CuO and Al react in situ to form nanoscale Al2O3 particles. Then the composites were cooled to a certain temperature under a certain pressure, and then cooled to room temperature to prepare (micron SiC+ nanometer Al2O3) / Al-Si dual-scale hybrid particle reinforced aluminum matrix composites. At the last, the composites were strengthened by heat treatment. The effects of in situ heating temperature and hot pressing pressure on the microstructure, hardness and wear resistance of the composites were studied. The results show that the aluminum matrix composites reinforced by micron-SiC and nano-Al2O3 hybrid particles, hot pressing strengthening and heat treatment strengthening have higher hardness and wear resistance. The heating temperature of in situ reaction is 620C, the hot-pressing temperature is 510C, and the hot-pressing pressure is 3Mpa. The microstructures of the composites are fine and compact, and the hardness and wear resistance of the composites are the best. The wear mechanism of composites is mainly abrasive wear.