航空接头锻件低速等温模锻成形及其塑性变形微观机理

摘要

采用低速等温模锻工艺制备7A85铝合金航空接头锻件,并对其在低速等温条件下塑性变形的微观机理进行分析.结果表明:低速等温模锻工艺有利于航空接头锻件的塑性成形,锻件成形质量良好,且锻件内部显微组织细小均匀.在低速等温变形条件下,晶界滑移是航空接头锻件塑性变形的主要机制,而扩散蠕变是晶界滑移的主要因素.基于空位扩散理论,建立7A85铝合金航空接头锻件在极低变形速度条件下的塑性变形本构方程,为低速等温锻造工艺提供理论指导.%The aviation forging of 7A85 aluminum alloy was prepared by the isothermal forging process with low speed, and the microcosmic mechanism of the plastic deformation was analyzed. The results show that the aviation forging is easily formed by using isothermal forging process with low speed, and the uniform microstructure is obtained. Grain boundary sliding is the main mechanism during the isothermal forging process with a low speed, and the diffusion creep is the main factor leading to the grain boundary sliding. Therefore, based on the vacancy diffusion theory, the plastic deformation constitutive equation of aviation forging under extremely low speed isothermal forging process is established in order to provide guidance for the low speed isothermal forging process.