Al_2O_3k/Al材料的反重力渗流铸造制备

Preparation of Al_2O_3k/Al materials by counter-gravity infiltration casting

采用氧化铝空心球作为造孔材料,通过反重力渗流铸造技术制备出基本无宏观铸造缺陷的氧化铝/铝基轻质复合材料(即Al2O3k/Al材料)。研究结果表明:渗流长度随熔体温度和空心球预热温度的提高以及空心球粒径的增大而增加,空隙度随着空心球粒径的增大而降低;增加充型与保压压力、延长保压时间以及添加金属Mg等均是改善渗流效果的有效手段。

Al2O3k/A1 materials without obvious macro casting defects were produced using alumina bubble brick as pore-forming materials through the counter-gravity infiltration casting system. The results show that along with the increase of the metal temperature and hollow balls preheating temperature and the particle size of hollow balls, the length of infiltration is getting longer. Besides, along with the increase of the particle size of the hollow ball, the void content decreases. Improving the filling and holding pressure, lengthening the holding time and adding metal Mg are the effective measures to improve infiltration process.