摘要
GH4169是一种重要的镍基高温合金，由于具有良好的合金性能，在航天航空发动机上得到广泛应用。
本文对热镦后GH4169螺母开裂进行了系统分析和初步探讨。提出了螺母镦制时，由于采用高频加热，加热速度快，参数不易控制，过热导致产生了δ相，在晶界及孪晶界析出，破坏了基体的连续性，以及应力集中两者的共同作用，是造成螺母开裂的根本原因。
GH4169 is a kind of very important nickel base heat-resistant alloy. It is used to manufacture aerospace engine mostly, for its best performance. This article was analyzed the crack of nuts after heat-heading, and found the cause why the crack was took place： use high frequency heating, the parameter was not easy to control, Overheated material made the δ phase, which had precipitated at the grain boundary and twin crystal boundary. The δ phase destroyed the matrix of continuity. The other cause is stress concentration. The nuts were cracked at both of the two factors.
