Coordinating control method of alpha2 phase and silicide in near-alpha high temperature titanium alloy

Abstract

The invention provides a method for coordinating and controlling alpha2 phase and silicide in a near-alpha titanium alloy. The method comprises the following steps of: 1. determination of an alloy system; 2. determination of variation ranges of contents of Al elements and Si elements; 3. determination of a smelting process; 4. determination of a rolling deformation process; 5. determination of solid solution microstructure; 6. selection of an aging heat treatment process. The method determines the compositional variation range of the Al elements and the Si elements in the near-alpha titanium alloy, determines a corresponding system of the heat treatment process, ensures that the alpha 2 and the silicide can be coordinated and controlled, and can simultaneously guarantee higher heat resistant performance and higher thermal stability.

Description

technical field [0001] The invention relates to a near-alpha high-temperature titanium alloy with alpha 2 Coordinated control methods for phases and silicides, especially α in Si-containing near-α high-temperature titanium alloys 2 Coordinated control methods of phases and silicides, such as α in the Ti-Al-Sn-Zr-Mo-Si alloy system 2 Coordinated control methods for phases and silicides. Background technique [0002] Near-alpha titanium alloys are the first choice for high-temperature titanium alloys used at temperatures above 600 °C. When the microstructure and added elements are fully guaranteed, the fundamental way to improve its high-temperature performance lies in the precipitation strengthening of the dispersed phase. Although alpha 2 Phases and silicides as dispersed precipitated phases are likely to cause a decrease in the thermal stability of the alloy, but they can indeed play a strengthening role. For example, in IMI550, IMI679, IMI685, IMI829, IMI834 and Ti-55,...

AI Technical Summary

Problems solved by technology

As mentioned earlier, due to α 2 The complexity of phase and precipitation processes of silicides, present, α 2 Coordinated control of phases and silicides remains an unresolved difficulty

[0013] In summary, the existing technical methods have the following defects, that is, improving the thermal strength of near-alpha high-temperature titanium alloys often will be at the expense of reducing thermal stability (usually represented by tensile plasticity index); Excellent thermal stability, but it is difficult to achieve high thermal performance at the same time