【摘要】 选用0.15μm和5μm的Al2O3颗粒,采用挤压铸造法制备了体积分数为40%的铝基复合材料。利用选区电子衍射和高分辨电子显微技术研究了Al2O3P/1070Al界面附近基体的显微组织。结果表明,复合材料增强体颗粒为5μm时,基体存在大量的由热错配应力引发的位错,颗粒粒径为0.15μm时,基体表现为近无位错的组织特征,其缺陷形式为1～5nm的“微畸变区”,这主要是由于粒径小、分布弥散,微区应力均匀所致。更多还原

【Abstract】 Aluminum based composites in a volume fractions of 40% were fabricated using the Al2O3 particles of 0.15 μm and 5 μm in sizes by extrusion casting technique. The microstructure characterization near the interfaces of Al2O3P/1070Al composites was investigated by SADP and HREM techniques. Results show that dislocations of high-density were generated in the Al2O3P/Al composite reinforced with Al2O3 particles of 5 μm due to the thermal mismatch stress. In contrast,free dislocations and some “micro distortion areas” of 1～5 nm were observed in the Al2O3P/Al composite reinforced with Al2O3 particles of 0.15 μm due to the dispersion of fine sub-micron particles and the uniform stress distribution near the interfaces.更多还原