Microstructure and mechanical properties of directly thixoforged complex box-shape 2A14 part with large wall-thickness difference  

直接触变锻造大壁厚差复杂壳体2A14合金件的显微组织与力学性能

作　　者：Ying-ze LIU Ju-fu JIANG Ying ZHANG Min-jie HUANG Jian DONG Ying WANG 刘英泽;姜巨福;张颖;黄敏杰;董健;王迎(哈尔滨工业大学材料科学与工程学院金属精密热加工国家级重点实验室,哈尔滨150001;哈尔滨工业大学机电工程学院,哈尔滨150001)

机构地区：[1]National Key Laboratory for Precision Hot Processing of Metals,School of Materials Science and Engineering,Harbin Institute of Technology,Harbin 150001,China [2]School of Mechatronics Engineering,Harbin Institute of Technology,Harbin 150001,China

出　　处：《Transactions of Nonferrous Metals Society of China》2024年第12期3876-3892,共17页中国有色金属学报（英文版）

基　　金：supported by the National Key R&D Program of China(No.2022YFB3404204);the National Natural Science Foundation of China(No.U2241232);the Foundation of National Key Laboratory for Precision Hot Processing of Metals,China(No.6142909230203).

摘　　要：To form complex box-shape parts with large wall-thickness difference,a directly thixoforged technology of 2A14 alloy with low-cost and short-process was proposed and verified.The results showed that complex components were successfully thixoforged.Solid grains in the microstructure of the thixoforged parts exhibited a large deformation degree.This led to an obvious improvement in the mechanical properties of the thixoforged parts.No obvious liquid segregation was found in the microstructure.High mechanical properties were obtained in the thixoforged 2A14 alloy components.The yield strength varied from 157.1 to 187.3 MPa,the ultimate tensile strength varied from 268.2 to 316.6 MPa,and the elongation varied from 7.8%to 24.9%.Increase in plastic deformation degree caused by larger size and less round grains is beneficial to the mechanical properties of the thixoforged components.针对大壁厚差复杂壳体件的成形,提出一种低成本、短流程的2A14合金直接触变锻造工艺,并进行验证。结果表明,复杂零件可以成功进行触变锻造。触变锻件组织中的固相晶粒表现出较大的变形程度,这使得触变锻件的力学性能有明显的改善。在显微组织中没有发现明显的液相偏析。触变锻造的2A14合金零件具有较高的力学性能,其屈服强度为157.1~187.3 MPa,极限抗拉强度为268.2~316.6 MPa,伸长率为7.8%~24.9%。较大的晶粒尺寸和较小的晶粒圆整度使塑性变形程度增大,有利于提高触变锻件的力学性能。

关 键 词：THIXOFORGING microstructure mechanical properties 2A14 aluminum alloy 

分 类 号：TG319[金属学及工艺—金属压力加工]