发动机铸钛机匣加工变形的真空热处理控制

Orthopaedics of the Turbine Casing by Vacuum Heat Treatment

涡喷发动机铸钛机匣为大型薄壁异型结构件 ,机加工后因残余应力的重新分布而导致其几何形状改变。利用真空热处理技术 ,消除了铸件毛坯及其经过机加工后所残留的应力 ,使问题获得了圆满的解决。借助金相、气体分析、力学性能以及结构尺寸测定等技术 ,对热处理规范的确定提供了科学依据 ,工艺可靠 ,效益可观。

The casing of turbine engine,which is made from cast titanium alloy ZT3and ZT4,may be distorted because a residual stress was caused by the casting and mechanical pro- cessing.The vacuum heat treatment can be used for eliminating residual stress on the turbine cas- ing and the operational program has been provided in the light of an experimental results.It is shown that annealing temperature being used in casting blank is650℃ for alloy ZT3and70 0℃ for alloy ZT4,and that the annealing temperature being used in eliminating residual stress,which was caused by the mechanical processing,is 60 0℃ for these alloys.