【摘要】 铸型材质不同,其冷却速度不同,它影响液态金属凝固过程及形成的组织,进而影响材料的性能。用铸造法制备复合材料时,铸型材质还会对增强体颗粒的分布产生影响。采用液态搅拌法制备了SiCp/ZAlSi5CuMg复合材料,研究了不同铸型材质、相同材质不同壁厚对SiCp/Al复合材料微观组织均匀性的影响规律。试验结果表明,在其他条件相同的情况下,采用冷却能力较快的铸型,可以明显改善SiC颗粒在ZAlSi5CuMg基体中分布的均匀性。冷却速度较快,凝固过程中金属液粘度迅速增大,使SiC颗粒聚集及下降时的阻力增大,难以聚集或下降,进而使SiC颗粒在ZAlSi5CuMg基体中分布的均匀性得到改善。更多还原

【Abstract】 SiCp/ZAlSi5CuMg composites was fabricated by melt stirring casting and the influence of cooling velocity of mold on its microstructure was investigated.The result shows that with cooling velocity increasing,the uniformity of SiC particles distribution in Al alloy matrix are obviously improved under otherwise identical conditions.The viscosity of melt increased quickly in solidification process as rate of melt solidification increasing so that SiC particles were difficult to sink and settle because of resistance increasing.These effects caused the uniformity of SiC particles distribution in the alloy ZAlSi5CuMg matrix improved obviously.更多还原