高强亚稳β钛合金变形机制及其组织调控方法

Metastable β titanium alloy has excellent overall properties, including low density, high specific strength, and good forming ability. Therefore, it has been successfully used to replace traditional high-strength steels in aerospace structural components with extremely-high strength requirements, resulting in significant structural weight reduction effects and greatly improved aircraft performance. The main method for preparing high-strength metastable β titanium alloy structural components is the combination of hot forming technology and heat treatment. The prerequisite for formulating and optimizing the processes is a thorough understanding of the alloy's deformation mechanism, followed by integrated control of the microstructure and properties of the components. Meanwhile, elucidating the relationship between the high-strength metastable β titanium alloy's deformation mechanism and its micromechanical properties will aid in the development of new alloys to meet the needs of aircraft for higher performance materials. Therefore, in this article, the deformation mechanism of the high-strength metastable β titanium alloy and its microstructure control methods was focused on and discussed, and first summarizes the research progress of the plastic deformation mechanism at room temperature, expounds the factors affecting the stability of the β matrix and the corresponding deformation mechanism evolution, analogizes the comprehensive influence of α phase characteristics on dislocation movement and the resulting mechanical performance. Furthermore, this article summarizes the hot deformation behavior and mechanism of a high-strength metastable β titanium alloy, analyzes the alloy's microstructure evolution and deformation mechanism in different phase regions and deformation stages, and discusses the alloy's work hardening and softening behaviors during hot deformation. Finally, the complex interaction of dynamic recovery or dynamic recrystallization and dynamic phase transformation in the microstructure control process of high-strength metastable β titanium alloy is briefly described, and the research status and development trend of multi-scale calculation models in alloy microstructure and performance prediction are discussed.