关键词: 大型钛合金构件, 等温局部加载, 内变量法, 晶粒尺寸, 加载方式

Abstract: In order to study the microstructure evolution rules in the isothermal local loading processes for large-sized titanium alloy components, the primary α-phase grain size variation processes of large-scale titanium alloy rib-web components during isothermal local loading were simulated and analyzed based on the internal variable microstructure model of TA15 titanium alloy. The local loading orders and integral loading mode were carried out as a comparison, so as to understand the microstructure evolution of the local loading. The results show that the transitional zones are affected by the transferred materials from the loading zones to unloading zones, the sizes of the primary α-phase grain after both of the loading steps are reduced, leading the sizes of the primary α-phase grains in this zone smaller than those zone away from the transitional zone. The switch of the first and second loading orders may change the quantity of transferred materials, so the loading order may affect the grain size variation processes on both sides of the die partition line. Compared with the integral loading mode, the grain size of local loading in the transitional zone is smaller. The grain size variation away from the transitional zone is almost indifference under above three loading methods.

Key words:  , large-sized titanium alloy component, isothermal local loading, internal state variable method, grain size, loading method