流变压铸A380铝合金的显微组织与力学性能-中国有色金属学报.PDFVIP

第 25 卷第 8 期 中国有色金属学报 2015 年 8 月 Volume 25 Number 8 The Chinese Journal of Nonferrous Metals August 2015 文章编号：1004-0609(2015)08-2029-11 流变压铸A380 铝合金的 显微组织与力学性能 祁明凡，康永林，周 冰，张欢欢，朱国明 (北京科技大学 材料科学与工程学院，北京 100083) 摘 要：将自主研发的强制对流搅拌制浆装置(FCM)与压铸机结合，以汽车控制臂为例，成功实现 A380 铝合金 的流变压铸成形。研究FCM 工艺参数下铸件组织特征的演变，对比传统压铸与 FCM 流变压铸工艺下铸件显微组 织、内部缺陷和力学性能的差异，分析 FCM 流变压铸工艺组织形成机理及其凝固行为。结果表明：适当提高螺 杆转速或降低内筒温度，均有利于改善铸件的组织形态；FCM 流变压铸工艺不仅可以获得内部组织细小、圆整且 分布均匀的铸件，而且可以显著减少铸件内部气孔缺陷和提高铸件的力学性能。和传统压铸件相比，FCM 流变压 铸件的抗拉强度、屈服强度和伸长率分别提高了 10%、4%和 140%。 关键词：A380 铝合金；强制对流搅拌；流变压铸；组织演变；力学性能 中图分类号：TG146.2 文献标志码：A Microstructures and mechanical properties of A380 aluminum alloy produced by rheo-diecasting process QI Ming-fan, KANG Yong-lin, ZHOU Bing, ZHANG Huan-huan, ZHU Guo-ming (School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China) Abstract: Taking auto control arms for example, the rheo-diecasting process of A380 alloy was obtained by combing a self-developed forced convection mixing rheoforming machine (FCM) with a diecasting machine. The microstructural characteristics of FCM rheo-diecasting parts in various processing parameters were investigated. The differences of microstructures, internal defects and mechanical properties in traditional diecasting parts and rheo-diecasting parts were compared. The formation mechanism and solidification behavior of semisolid slurry were analyzed in FCM rheo-diecasting process. The results show that raising rotation speed or decreasin