TC4-DT合金通过三重热处理得到三态组织的研究

The Study of the Process of TC4-DT Alloy Resulting in Tri-modal Structure through Triple Heat Treatment

摘要:

研究了钛合金TC4-DT在高温热变形后进行的三重热处理对微观组织的影响。结果表明：三重热处理工艺中第一重温度与第二重温度影响着合金组织的中等轴α相的含量，伴随着第一重温度与第二重温度的升高，等轴α相含量逐渐减少；将高温变形后的组织通过940℃?h譝Q 920℃?h譝Q 820℃?.5h譇C热处理可以得到三态组织，其中约含20%等轴α、50%～60%条状α构成的网篮和β转变基体；且条状α相构成的网篮中，一次次生条状α相间还含有更细小二次次生条状α相，这种组织具有较小的纵横比，各α集束交错排列，细化了组织。

Abstract:

In this article, it studies the effect of TC4 - DT titanium alloy''s triple heat treatment on microstructur-e after thermal deformational at high temperature. It shows that the first temperature and the second temper-ature which in the triple heat treatment influenced the amount of alpha phase in alloy microstructure, m-oreover ,with the increasing of the first temperature and the second temperature, equiaxed alpha phase w-ould gradually decease. The tri-modal structure which results from 940℃?h WQ 920℃?h WQ 820℃?.5h AC, which consists of about 20% equiaxed alpha, 50%~60% basketweave formed by striature alpha and transformed beta matrix.Further more, there are smaller secondary strip alpha among first strip alpha in the basketweave which formed by striped alpha, the microstructure has a smaller aspect ratio and the alpha staggered cluster that refined the microstructure.