增材制造Ti-6Al-4V合金微观组织等轴化调控研究进展

Research Progress on Equiaxed Microstructure Regulation of Additively Manufactured Ti-6Al-4V Alloy

摘要:

Ti-6Al-4V合金因其优异的比强度、耐腐蚀性和生物相容性，在航空航天、生物医疗等领域广泛应用。然而，增材制造过程中快速凝固和复杂热循环常导致钛合金形成粗大的柱状β晶粒，带来力学性能的各向异性和疲劳性能下降。实现微观组织的等轴化调控是提升增材制造钛合金综合性能的关键。本文系统总结了通过微合金化、外场辅助和热处理等手段实现TC4合金微观组织等轴化研究进展。重点探讨了α稳定元素、β稳定元素、外场辅助技术以及热处理工艺对Ti-6Al-4V合金微观组织和力学性能影响机制，并展望了未来在精确调控微观组织、优化工艺参数和开发高性能钛合金方面的研究方向。本文旨在为增材制造钛合金的微观组织优化和性能提升提供理论指导和技术支持。

Abstract:

Ti-6Al-4V alloy is widely used in aerospace, biomedical, and other fields due to its excellent specific strength, corrosion resistance, and biocompatibility. However, rapid solidification and complex thermal cycling during additive manufacturing often lead to the formation of coarse columnar β grains in titanium alloys, resulting in anisotropic mechanical properties and reduced fatigue performance. Achieving equiaxed microstructure control is crucial for improving the comprehensive properties of additively manufactured titanium alloys. This work reviewed recent advances in achieving equiaxed microstructures of Ti-6Al-4V (TC4) alloy through microalloying, composite fabrication, external field assistance, and heat treatment. The influence mechanisms of α-stabilizing elements, β-stabilizing elements, external field-assisted techniques, and heat treatment processes on the microstructure and mechanical properties of Ti-6Al-4V alloy were discussed. Furthermore, future research directions were outlined, focusing on precise microstructure control, process parameter optimization, and the development of high-performance titanium alloys. The aim of this work is to provide theoretical guidance and technical support for microstructure optimization and performance enhancement of additively manufactured titanium alloys.