Ni-Ti基合金的应变玻璃转变及其研究进展  

Progress in research on strain glass transition in Ni-Ti based alloys

作　　者：赵新青[1] 王凯[1] 吕超 张凯超 侯慧龙 ZHAO Xinqing;WANG Kai;LYU Chao;ZHANG Kaichao;HOU Huiong(School of Materials Science and Engineering,Beihang University,Beijing 100191,China)

机构地区：[1]北京航空航天大学材料科学与工程学院,北京100191

出　　处：《航空材料学报》2025年第1期1-14,共14页Journal of Aeronautical Materials

基　　金：国家自然科学基金(51971009)。

摘　　要：近等原子比Ni-Ti合金因热弹性马氏体相变而呈现形状记忆效应和超弹性,并广泛应用于生物医疗和诸多工业领域。近年来的理论和实验研究表明,当近等原子比Ni-Ti合金引入足够的缺陷(如溶质原子、位错以及纳米析出物)时,这些缺陷导致的相变阻力可有效抑制合金的一级马氏体相变,并代之以短程有序的晶格应变微区(纳米马氏体畴)为显著特征的应变玻璃转变。Ni-Ti基应变玻璃具有宏观晶体结构不变、各态遍历性缺失、动态力学性能随频率弥散分布和高阻尼等特征。尽管应变玻璃在冷却过程中不发生一级马氏体相变,但因应力加载诱发应变玻璃向马氏体转变及应力卸载时的逆转变,应变玻璃仍然可呈现出优异的形状记忆效应和超弹性。应变玻璃合金的超弹性与缺陷类型及浓度密切相关,缺陷浓度不高的应变玻璃具有与传统Ni-Ti基合金类似的超弹性行为;高缺陷浓度的应变玻璃在温度场和应力场作用下发生应变玻璃↔R相变,其超弹性具有小回复应变、窄滞后和宽温域特征。Ni-Ti合金可通过变形引入大量位错缺陷,以实现其应变玻璃转变。应变玻璃在应力作用下如果只涉及纳米畴演化而不发生B19′马氏体转变,可表现出具有窄滞后特征(近线性)的大超弹性,其物理机制在于应力作用下纳米畴的演化不需要形核过程,从而避免因形核导致的能量损耗。本文综述了Ni-Ti基合金应变玻璃转变的提出、奇异性质及其研究进展,并对基于应变玻璃转变的Ni-Ti基宽温域超弹性合金设计原理及工程应用作了简要介绍。Equiatomic Ni-Ti alloys have been widely applied in biomedical and industrial fields,because of their shape memory effect and superelasticity originating from thermos-elastic martensitic transformation.The theoretical and experimental studies in recent years indicated that when doping sufficient amounts of defects(excess solute atoms,foreign alloying dopants,dislocations and nanosized precipitates)into equiatomic Ni-Ti alloys,the resistance from such defects could suppress the first-order martensitic transformation and achieve strain glass transition with the formation of randomly short-range ordered nanodomains.The strain glass transition is characterized by some typical features such as invariant macroscopic structure,broken ergodicity,frequency dependence of dynamic mechanical properties and high damping capacity.In spite of no first order martensitic transformation occurred during cooling,strain glass can exhibit unique shape memory effect and superelasticity because of the stress loading induced transformation from strain glass to martensite and the reversed transformation by stress unloading.The superelasticity of strain glass alloys are closely related to the type and concentration of defects.The strain glasses with moderate concentration of defects exhibit the superelastic behavior similar to conventional Ni-Ti based alloys.By contrast,under temperature or/and stress fields the strain glass←→R transition could occur in the strain glasses with high concentration of defects,leading to the superelasticity with small recovery strain and slim hysteresis over a broad temperature range.Strain glass transition could be achieved in Ni-Ti alloys by deformation to introduce large number of dislocations.If only the evolution of nanodomains is involved and no B19′martensite forms in the Ni-Ti strain glass under external stress,the alloy could perform large linear superelasticity with slim hysteresis.The underlying mechanism for such superelastic behavior lies in that under stress the evolution of nanodomains doe

关 键 词：Ni-Ti基 马氏体相变 应变玻璃转变 形状记忆效应 超弹性 

分 类 号：V252[一般工业技术—材料科学与工程]