摘要
根据实际应用价值将形状记忆合金分为三类:NiTi-基、Cu-基和Fe-基合金。NiTi-基形状记忆合金在记忆合金应用领域一直处于统治地位,但其材料成本高、冷加工性能差;Cu-基形状记忆合金热加工性能和形状记忆效应均较好且价格低廉,但存在记忆性能不稳定、晶粒粗大、抗疲劳性能差等缺陷,阻碍了其研究和应用;Fe-基形状记忆合金自开发以来因其价格低廉、加工性能优良、可焊接性好等特点,备受人们青睐,被确定为具有发展前景的新型形状记忆材料。Fe-基形状记忆合金中的马氏体相变主要分为三种,分别是由面心立方fcc(γ)→面心正方fct、体心正方bct和密排六方hcp(ε)。因fcc(γ)→fct马氏体相变及其逆相变而呈现形状记忆效应的合金有Fe-Pd和Fe-Pt;因fcc(γ)→bct马氏体相变及其逆相变而呈现形状记忆效应的合金有Fe-Ni-Ti-C和Fe-Ni-Co-Ti;因fcc(γ)→hcp(ε)中的Pd、Pt价格昂贵,故其实用意义不是很大,不作为研究和应用的热点。由于Fe-Mn-Si系形状记忆合金的马氏体起始相变温度(Ms)接近室温、形状记忆效应相对较好,因此具有很好的应用前景。但此类合金存在相对较低的Ms以及明显的滞后现象限制了它们的广泛使用。Fe-Ni-Co-Ti马氏体界面的能动性不因热滞大小而改变,通过冷却或加热使移动的马氏体界面长大或收缩。基于Fe-Ni-Co-Ti合金超弹性的研究开发的新型Fe-Mn-Al-Ni合金所表现的超弹性更加优异,Fe-Mn-Al-Ni合金在室温下具有低应力滞后的超弹性响应,主要特征是:在-196~240℃温度范围内,诱导马氏体转变所需的应力对温度依赖性较低,大大拓宽了Fe-基形状记忆合金的应用。本文分类介绍了Fe-基形状记忆合金近年来的研究进展以及相关性能,尤其对Fe-Mn-Si系形状记忆合金中各元素对合金的影响进行了详细的介绍,以期在合金的成分设计方面为相关研究人员提供参考,并提出了现阶段Fe-基形状记忆合金所存在的问题。
Shape memory alloys are classified into three categories according to practical application values:NiTi-based alloys,Cu-based alloys and Fe-based alloys.The field of shape memory alloys has been dominated by NiTi alloys.However,NiTi-based shape memory alloys have the di-sadvantages of high material cost and poor cold workability.The Cu-based shape memory alloys have good hot workability and shape memory effect,but the Cu-based shape memory alloy have unstable memory performance,coarse grain and poor fatigue resistance,which hinders its research and application.Fe-based shape memory alloys have attracted much attention for their low cost,excellent workability and good weldability,and have been identified as a new shape memory material with promising development.The martensitic transformation of Fe-based shape memory alloys is mainly divided into three types,namely,face-centered cubic fcc(γ)→face-centered square fct,body-centered square bct,and close-packed hexagonal hcp(ε).Alloys with fcc(γ)→fct martensitic transformation and reverse phase transformation to achieve shape memory effect are Fe-Pd and Fe-Pt alloys.Alloys obtained by fcc(γ)→bct martensitic transformation and reverse phase transformation to obtain shape memory effects include Fe-Ni-Ti-C and Fe-Ni-Co-Ti alloys.The shape memory effect of the Fe-Mn-Si alloy exhibites the fcc(γ)→hcp(ε)martensitic transformation and its reverse phase transformation.Because Pd and Pt are expensive,the Fe-Pt/Fe-Pd shape memory alloys are not very practical and only used for academic research.Fe-Mn-Si shape memory alloy has a phase transition temperature close to room temperature and a relatively good shape memory effect,which makes it have a good application prospect.Because of Ms and large hysteresis,it hinders the wide range of applications of Fe-based shape memory alloys.However,the Fe-Ni-Co-Ti martensite interface has a initiative that does not change due to the thermal hysteresis.When the alloy is cooled or heated,it grows and contracts due to the movement of the martensite interface.Major success is now within reach with new class of Fe-Mn-Al-Ni alloys on the basis of the superelastic study of Fe-Ni-Co-Ti alloy.They exhibit superior superelastic properties and undergo superelasticity response at room temperature with low stress hysteresis.One of the characteristics of Fe-Mn-Al-Ni alloy is that the stress required to induce martensitic transformation has a low temperature dependence over a broad range,-196℃to 240℃.This greatly broadens the application of Fe-based SMAs.In this paper,the research progress of Fe-based shape memory alloys and their related properties are introduced in recent years.In particular,the effects of various elements in Fe-Mn-Si shape memory alloys on alloys are introduced in detail,which is related to the composition design of alloys.In the aspect of alloy composition design,this paper provides a reference for relative researchers and points out the existing problems at the present stage.
作者
邹芹
党赏
李艳国
王明智
熊建超
ZOU Qin;DANG Shang;LI Yanguo;WANG Mingzhi;XIONG Jianchao(School of Mechanical Engineering,Yanshan University,Qinhuangdao 066004;State Key Laboratory of Metastable Materials Science and Technology,Yanshan University,Qinhuangdao 066004)
出处
《材料导报》
EI
CAS
CSCD
北大核心
2019年第23期3955-3962,共8页
Materials Reports
基金
河北省自然科学基金资助项目(E2015203232)
“河北省首批青年拔尖人才支持计划”资助项目(冀组字[2016]9号文件)
“丹凤朝阳人才计划”(丹人才办[2019]3号)资助~~
关键词
形状记忆效应
马氏体相变
合金元素
非热弹性
shape memory effect
martensitic transformation
alloying elements
nonthermoelastic
