激光选区熔化技术制备NiTi合金的研究进展与应用

NiTi合金作为一种典型的形状记忆合金，除了具有独特的形状记忆效应，还拥有优异的超弹性、生物相容性和力学性能，广泛应用于医学、机械、微电子等领域。然而，由于该合金延展性过高、加工硬化、低热导等问题，传统的切削方法加工工艺复杂、成本高，限制了其工程化应用。增材制造技术（Additive manufacturing, AM）又称3D打印技术，以其独特的一体化成形的技术优势，有效地改善了传统加工方法存在的问题。对此，国内外学者对激光选区熔化（SLM） 3D打印镍钛合金成形工艺进行了大量研究，并取得了丰硕成果。综述了近年来选区激光熔化镍钛的研究进展，简述了选区激光熔化和热处理工艺与镍钛合金的相变温度、组织结构、力学性能等映射关系，着重分析了SLM工艺参数对镍钛合金超弹性的影响规律，揭示了其影响机制，介绍了激光选区熔化镍钛合金的在医学领域的应用，并对未来NiTi合金的增材制造技术的发展提出了展望。

Research Progress and Application of Laser Selective Melting Technology for Preparing NiTi Alloys

NiTi alloy， as a typical shape memory alloy， exhibits excellent super elasticity， biocompatibility， and mechanical properties except for unique shape memory effects. It has been widely applied in fields of medicine， machinery， and microelectronics. However， traditional cutting methods face challenges such as complex processings and high costs due to the high ductility， work hardening， and low thermal conductivity of NiTi alloy， Additive Manufacturing （AM）， also known as 3D printing technology， has a unique advantage in integrated shaping to effectively address these challenges. Consequently， significant researches have been conducted on the selective laser melting （SLM） process for nickel-titanium alloys， yielding fruitful achievements. This article provides an overview of recent advancements in the research on selective laser melting of nickel-titanium. It outlines the interrelationships between SLM process parameters， heat treatment processes， and the phase transition temperature， microstructure， and mechanical properties of nickel-titanium alloys. The focus is placed on analyzing how SLM process parameters influence the superelasticity of nickel-titanium alloys while uncovering the underlying mechanisms. Furthermore， the medical applications of SLM-NiTi alloys are discussed. Finally， an outlook on the future development of additive manufacturing technology for NiTi alloys are presented.