Research on semi-solid thixoforming process of AZ91D magnesium alloy brackets for generators in JH70-type motorbikes

作     者：WANG Kai LIU Changming HAN Zhaotang CAO Jianyong ZHANG Zonghe WANG Kai1), LIU Changming1), HAN Zhaotang1), CAO Jianyong2), and ZHANG Zonghe2) 1) College of Mechanical Engineering, Chongqing University, Chongqing 400044, China 2) Chongqing Magnesium Industry Ltd. Co., Chongqing 401326, China

作者机构：College of Mechanical Engineering Chongqing University Chongqing 400044 China Chongqing Magnesium Industry Ltd. Co. Chongqing 401326 China 

出 版 物：《Rare Metals》 (稀有金属（英文版）)

年 卷 期：2005年第24卷第4期

页      面：381-391页

核心收录：

学科分类：082304[工学-载运工具运用工程] 08[工学] 080204[工学-车辆工程] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0802[工学-机械工程] 0823[工学-交通运输工程] 

主　　题：semi-solid thixoforming AZ91D magnesium alloy bracket motorbike 

摘      要：The investment on semi-solid die casting processes of AZ91D magnesium alloy brackets for generators in JH70-type motorbikes is introduced. The processes of low super-heat and cooling slope for the preparation of billets with non-dendritic microstructure, the remelting of billets for thixoforming and the parameters in the process of semi-sohd thixoforming have been researched. The results show that primary billets with non-dendritical structures can be prepared by forming great amount of nuclei in melt via the process of low super heat. By optimizing the remelting process through adjusting the current of the induced equipment, semi-solid billets with a structure of spherical grains were obtained from the primary billets with non-dendritical structure. The range of 580℃ to 583℃ is the proper remelting temperatures by which the billets have an expected thixotropy and can be transferred to a die-casting machine. The optimized parameters of semi-solid forming in a die-casting machine are as follows： the area of the ingate in the die is 383.5 mm^2, the speed of the pierce of the machine 5 m/s, the shot pressure of the pierce 75 MPa, and the maintenance pressure of the pierce 350 MPa. The castings of brackets for supporting generators in JH70 type motorbikes were formed by adopting the optimized processes and parameters mentioned above.