铝镁合金铸件用复合硫酸盐水溶性砂芯性能的研究  

Research on the Performance of Water-Soluble Composite Sulfate Sand Core for Aluminum Alloy and Magnesium Alloy Castings

作　　者：姜鹏[1] 樊自田[1] 刘富初[1] 刘鑫旺[1] 

机构地区：[1]华中科技大学材料成形与模具技术国家重点实验室,湖北武汉430074

出　　处：《铸造》2015年第6期493-498,共6页Foundry

基　　金：国家自然科学基金资助项目(51375187)

摘　　要：针对铝镁合金复杂薄壁铸件铸后清理难的问题,以硫酸镁和硫酸铝复合溶液为粘结剂,采用二次微波加热硬化工艺制备了复合硫酸盐水溶性砂芯。对比分析了硫酸镁水溶性砂芯和硫酸铝水溶性砂芯的性能特征,研究了复合硫酸盐水溶性砂芯性能的影响因素,测试了复合硫酸盐水溶性砂芯的水溶溃散性,通过环境扫描电镜分析了复合硫酸盐水溶性砂芯的微观形貌。结果表明:二次微波加热硬化复合硫酸盐水溶性砂芯具有较优的综合性能,其即时抗拉强度可达1.3 MPa、4 h存放强度约1 MPa,铸后水溶溃散性优异,水溶速率可达50.74 kg/(min·m2)。微观分析结果表明:粘结桥吸水而出现裂纹或孔洞,导致砂芯强度降低。To overcome the poor leachability of the sand cores for complicated thin-walled aluminum/ magnesium alloy castings, a water-soluble composite sulfate sand core hardened by twice microwave heating technology using composite solution of MgSO4 and Al2（SO4）3 as a binder was investigated in the paper. The performance characteristics of MgSO4 and Al2（SO4）3 water-soluble sand core were analyzed and compared, the influencing factors of the performance of the water-soluble composite sulfate sand core were investigated, and the water-soluble rate of the sand core was measured, environmental scanning electron microscope was used to investigate the micro-morphology of the water-soluble composite sulfate sand core. The results show that the water-soluble composite sulfate sand core hardened by twice microwave heating technology possesses optimum comprehensive performances, and its immediate tensile strength can exceed 1.3 MPa, the 4 h storage strength is about 1 MPa, besides the water-soluble rate is up to 50.74 kg/（min·m^2） that indicates the sand core has an outstanding water-soluble collapsibility. The microscopic analysis demonstrates that absorbing water of binder bridges caused cracks or holes, then led to the decrease of sand core strength.

关 键 词：水溶性砂芯 二次微波加热 抗拉强度 硫酸镁 硫酸铝 

分 类 号：TG22[金属学及工艺—铸造]