轻量高强Ti-Zr基形状记忆合金的超弹性研究

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中图分类号：TG146.4 文献标志码：B DOI：10.19710/J.cnki.1003-8817.20250261

Research on Superelasticity of a Lightweight and High-Strength TiZr-based Shape Memory Alloy

LiShuanglei， Yang Jiayi，Yuan Siyu， Wang Xu （Collegeof Materials Science and Engineering，Huaqiao University，Xiamen 361021）

Abstract：To investigate the efectof solid solutionstrengthening from interstitial oxygen on the mechanical propertiesand superelasticity of lightweight Ti-Zr-based shape memoryaloys，a Ti-4OZr-8Nb-2Sn（at. % ）alloyis selected as the studied object.By doping 0.2 at. % oxygen and applying 2 different heat treatments-a single-step annealing at 550 for 3O min and a two-step treatment consisting of annealing at 600 for10 min followed by aging at 300 °C for 6O min——the mechanical behavior and microstructure are characterized using room-temperature tensile tests，X-RayDiffraction （XRD），and Transmission Electron Microscopy（TEM）.Oxygendopingsignificantly increasedtheyield strength from 540 MPato805MPaandraised therecoverablestrain from2.5% to 3.7%.Afterthe two-stepheattreatment，themicrostructureisrefined，resultinginafurtherincreaseinyieldstrength to87OMPa，a recoverablestrainof 4.6% ，whilemaintainingafractureelongationof 16% .Microscopicanalysisrevealed theformation of nanoscale isothermal ω phase within the β matrix. The synergistic strengthening eect of interstitial oxygen solid solutionand thenanoscaleω phase induced bythe two-stepheat treatment efectivelyenhances the strength and optimizes thesuperelasticity of the Ti-Zr-Nb-Sn-Oaloy，providinga feasible pathway for developing high-strength， lightweight shape memory alloys for automotive applications.

Keywords：Shapememoryalloy，Ti- ∇⋅Zr -basedalloy，Lightweighthigh-strength，Superelasticity

1前言

形状记忆合金（Shape MemoryAlloy，SMA）作为重要的未来智能材料，因具有独特的形状记忆效应和超弹性，已在航空航天等高新技术领域获得重要应用[1-2]。（剩余8095字）