激光选区熔化成形高强钛合金研究现状及展望

Research Status and Prospects of High-Strength Titanium Alloys Fabricated by Selective Laser Melting

摘要:

以近/亚稳β钛合金为代表的高强钛合金具有高的比强度、良好的塑性加工性能、优异的淬透性以及可通过热处理强化获得强度-塑性-韧性匹配，已广泛应用于航空航天等领域重大装备承力构件。激光选区熔化（SLM）作为钛合金增材制造领域的一项重要技术，具有可以实现近净成形、复杂结构一体化成形等显著优势，成为航空航天制造领域的重点发展技术和前沿方向。本文围绕SLM成形原理和特点，从SLM成形高强钛合金经历极高加热/冷却速率以及独特的热循环历史出发，重点介绍了高强钛合金微观结构特征、相组成以及力学性能特点。总结了SLM高强钛合金热处理工艺种类及其主要影响规律，旨在为获得优异的力学性能匹配提供参考。最后，根据对现有研究成果的分析，总结了SLM成形高强钛合金研究面临的挑战，并对未来该领域可能的研究方向作了展望。

Abstract:

High-strength titanium alloys, represented by near/metastable β titanium alloys, have high specific strength, good plastic processing properties, and excellent hardenability, and they can be strengthened through heat treatment to get a better match of strength-plasticity-toughness. They have been widely used in load-bearing components of major equipment in aerospace and other fields. Selective laser melting (SLM), as an important technique in the field of titanium alloy additive manufacturing, has significant advantages such as near-net shaping and integrated forming of complex structures. So it has become a key development technique and cutting-edge direction in the aerospace manufacturing field. This review focuses on the principle and characteristics of SLM, starting from the extremely high heating/cooling rate and unique thermal cycle history of SLMed high-strength titanium alloy, and primarily discusses the microstructural features, phase composition, and mechanical properties of high-strength titanium alloys. The types of heat treatment processes of SLMed high-strength titanium alloy and their main influencing rules are summarized, aiming to provide a reference for obtaining excellent mechanical property match. Finally, drawing upon an analysis of existing research outcomes, the challenges of SLMed high-strength titanium alloys are summarized. It also offers a forward-looking perspective on potential research directions in this field.