金属学报, 2025, 61(6): 809-825 DOI: 10.11900/0412.1961.2024.00264

综述

零热膨胀金属材料研究进展

宋玉柱,1, 张济民1, 周畅2, 施耐克1, 陈骏,1

1 北京科技大学 物理化学系 北京 100083

2 北京科技大学 新金属材料国家重点实验室 北京 100083

Research Progress on Zero Thermal Expansion Metallic Materials

SONG Yuzhu,1, ZHANG Jimin1, ZHOU Chang2, SHI Naike1, CHEN Jun,1

1 Department of Physical Chemistry, University of Science and Technology Beijing, Beijing 100083, China

2 State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, China

通讯作者: 宋玉柱,yuzhusong@ustb.edu.cn,主要从事低膨胀合金和磁性材料研究;陈 骏,junchen@ustb.edu.cn,主要从事磁电热固体功能材料结构、性能及产业化应用研究

责任编辑: 肖素红

收稿日期: 2024-07-31   修回日期: 2024-12-07  

基金资助: 国家重点研发计划项目(2022YFE0109100)
国家自然科学基金项目(22275014)
国家自然科学基金项目(12104038)
北京高等学校卓越青年科学家计划项目(JWZQ20240101015)

Corresponding authors: SONG Yuzhu, associate professor, Tel:(010)62332265, E-mail:yuzhusong@ustb.edu.cn;CHEN Jun, professor, Tel:(010)62332265, E-mail:junchen@ustb.edu.cn

Received: 2024-07-31   Revised: 2024-12-07  

Fund supported: National Key Research and Development Program of China(2022YFE0109100)
National Natural Science Foundation of China(22275014)
National Natural Science Foundation of China(12104038)
Beijing Outstanding Young Scientist Program(JWZQ20240101015)

作者简介 About authors

宋玉柱,男,1990年生,副教授,博士

摘要

随着科技的进步,人们对太空、海洋和地下资源的探索不断深化,需要在极端条件下运行的设备日益增多,对材料的热膨胀性能调控要求也越来越高。零热膨胀金属材料的尺寸在温度变化的环境中依然能够保持不变,这一特殊功能对于需要高精密、高稳定性的器件来说具有重要应用价值。本文总结了因瓦(Invar)合金被发现100多年以来的零热膨胀金属材料的研究进展,从零热膨胀金属材料的定义、分类、发展历程进行综述,介绍了诱导金属材料零热膨胀的几种主要机制,同时列举了几类零热膨胀性能优异且应用价值高的金属材料,并对不同类型金属材料的晶体结构、零热膨胀性能和热膨胀调控方法等进行了阐述,讨论了磁性、相转变与热膨胀性能之间的耦合关系。最后对零热膨胀金属材料未来发展趋势进行了展望。

关键词: 零热膨胀; 低热膨胀合金; 金属功能材料; 热膨胀调控

Abstract

With the advancement of technology, the exploration of space, oceans, and underground resources continues to deepen. An ever-increasing demand for devices that operate under extreme conditions propels the need for the precise control of the thermal expansion properties of the materials used. Zero thermal expansion metals exhibit constant dimensions despite temperature variations, a unique feature that imparts these metals a significant application value in high-precision and high-stability devices. This article summarizes the research progress on zero thermal expansion metals since the discovery of Invar alloy over a century ago. It provides an overview of the definition, classification, and historical development of zero thermal expansion metals. Furthermore, this article introduces several main mechanisms inducing zero thermal expansion in metals and highlights several categories of metals with excellent zero thermal expansion properties and high application value. Moreover, it discusses the crystal structures, zero thermal expansion properties, and methods for controlling the thermal expansion properties of different types of metals. The coupling relationship between the magnetism, phase transitions, and thermal expansion properties is explored. Finally, the article provides a perspective on future trends in the development of zero thermal expansion metals.

Keywords: zero thermal expansion; low thermal expansion alloy; functional metallic material; thermal expansion control

PDF (3675KB) 元数据 多维度评价 相关文章 导出 EndNote| Ris| Bibtex  收藏本文

本文引用格式

宋玉柱, 张济民, 周畅, 施耐克, 陈骏. 零热膨胀金属材料研究进展[J]. 金属学报, 2025, 61(6): 809-825 DOI:10.11900/0412.1961.2024.00264

SONG Yuzhu, ZHANG Jimin, ZHOU Chang, SHI Naike, CHEN Jun. Research Progress on Zero Thermal Expansion Metallic Materials[J]. Acta Metallurgica Sinica, 2025, 61(6): 809-825 DOI:10.11900/0412.1961.2024.00264

热膨胀是材料固有的物理性质,然而材料的热胀冷缩给现代工业和日常生活带来诸多问题,尤其在精密仪器、微电子、航空航天等高新技术领域,如激光探测器受热膨胀后导致光路漂移、芯片与封装材料的热膨胀不匹配导致分离脱落、航天器在极端环境中因热胀冷缩而疲劳损坏甚至失效等[1]。由于原子间存在非谐效应,大多数材料的长度或体积都会随温度改变而变化,虽然变化微小,但对高精尖领域器件的功能和精度影响非常大[2]。热胀冷缩问题已经成为一些领域快速发展的限制环节,尤其在服役温度变化大的航空/航天领域,需要高性能低热膨胀材料以满足苛刻的尺寸和精度要求。因此,亟需研发出具有优异力学性能的零热膨胀材料[3,4]

零热膨胀(zero thermal expansion,ZTE)作为一种罕见的热膨胀性能自发现以来就备受关注。关于零热膨胀材料的研究最早可以追溯到1897年因瓦(Invar)合金的发现,Guillaume[5]研究表明,在很宽的温度范围内,Fe0.65Ni0.35合金的长度基本不发生改变。Invar这个词就是来源于Invariant,因此最初具有低热膨胀系数的合金被称为Invar合金,这些异常的热膨胀现象被称为Invar效应。Invar合金被发现之后被广泛应用于各个领域,如高精度机械、惯性导航系统、卫星和航天器、激光系统和光学仪器。自从1996年ZrW2O8的优异负热膨胀性能被报道之后[6],反常热膨胀材料得到广泛关注,零热膨胀、低热膨胀和负热膨胀等术语逐渐流行起来。

目前普遍认为零热膨胀是指在一定温度范围内材料的平均线膨胀系数(αl)的绝对值小于2 × 10-6 K-1。零热膨胀材料的尺寸基本不随温度变化而发生改变,其在受到热膨胀困扰的领域可以发挥重要作用,能够用来解决多种工业难题。随着科技的发展,人们对太空、海洋及地矿资源的探索越来越深入,需要在极端条件下服役的设备越来越多,对材料热膨胀性能的调控提出越来越高的要求,因此近30年来零热膨胀材料的研究得到广泛关注,一系列新的零热膨胀金属材料陆续被发现[2,7,8]。本文综述了Invar合金被发现100多年来零热膨胀合金的研究进展,总结了金属材料的零热膨胀诱导机制,分类讨论了零热膨胀金属材料体系,并展望了零热膨胀金属材料研究的未来发展趋势,以期为零热膨胀金属材料的研究及应用提供参考。

1 金属材料零热膨胀诱导机制

晶格非简谐振动会使金属材料产生正热膨胀,若想形成零热膨胀必须存在一种负热膨胀效应将此正热膨胀抵消(图1),目前金属材料中能产生负热膨胀作用的主要是磁体积效应(magnetovolume effect,MVE)[7,9]、马氏体相变[10,11]和价态转变[12,13],这几种作用可以使单相金属材料中出现负热膨胀现象,通过成分控制和化学替代可以将负热膨胀单相调控为零热膨胀。双相或者多相合金中若存在负热膨胀相,通过负热膨胀相补偿普通材料的正热膨胀也可以达到整体零膨胀的效果。

图1

图1   金属材料的零热膨胀:来源于晶格振动对体积正的贡献(ΔV2)与磁体积效应、马氏体相变或价态转变对体积负的贡献(ΔV1)相互抵消的结果

Fig.1   Zero thermal expansion (ZTE) of metallic materials, originates from the mutual cancellation between the positive contribution to volume (ΔV2) from lattice vibrations and the negative contributions to volume (ΔV1) from magnetovolume efect, martensitic phase transitions, or valence state changes (TC—Curie temperature)


1.1 磁体积效应

原子间磁交互作用会使金属材料出现长程的磁有序,磁体积效应是指材料的体积随着有序磁矩大小的变化而发生改变,一般情况下有序磁结构的体积大于无序磁结构(图2[9]),在温度升高到Curie温度以上时,磁性合金中磁矩排列由有序变得无序,对应的体积由大变小,这种效应刚好抵消原子非简谐振动产生的正热膨胀时,便会发生零热膨胀现象[7,9]。Guillaume[5]最先在铁磁Invar合金中发现了这一效应,但100多年来人们对于Invar合金反常热膨胀机理的认识依然存在许多争议。最近,Song等[7]研究表明,反常热膨胀不仅发生在常规的磁有序-无序转变中,还出现在局部磁矩改变、变磁转变、短程磁有序、磁结构相变和磁相分离转变中。在同一材料体系中,不同磁结构对应的体积不同,所有类型的磁性转变都存在磁体积效应,若想实现零热膨胀必须增强磁转变,使其产生的磁体积效应与晶格热振动相互抵消。

图2

图2   铁磁有序磁结构逐渐转变为无序顺磁结构时Invar合金体积逐渐缩小的过程[9]

Fig.2   Volume (showed by numbers) decreases of the Invar alloy as the ferromagnetic ordered magnetic structure transitions to a disordered paramagnetic structure[9]


1.2 马氏体相变

一些金属材料在温度改变时会发生马氏体相变,在升温过程中由低温马氏体相转变为高温奥氏体相,而马氏体相的晶格常数比奥氏体相大很多,导致相变过程中晶格产生巨大收缩,因此金属材料中出现巨大负热膨胀现象[10,11]。通过改变马氏体相变的稳定性,调整马氏体和奥氏体的比例,可以将窄温区的巨大负热膨胀调控为宽温区的零热膨胀。马氏体相变为一级相变,其诱导的异常热膨胀容易出现比较大的滞后,但是马氏体相变产生的巨大负热膨胀比其他因素诱导的负热膨胀强很多。

1.3 价态转变

由于不同价态离子的半径不同,当温度变化导致离子的价态发生转变时,会引起化合物体积的变化。价态转变现象广泛存在于稀土基化合物、硫化物、过渡金属氧化物、金属间化合物等多种类型化合物中。目前金属材料中最容易出现价态转变的是稀土元素Yb、Sm和Ce,不同价态稀土离子的能量非常接近,容易受到温度波动的影响而发生价态转变。例如,由于Yb2+半径比Yb3+大,升温过程中Yb2+向Yb3+的转变可能导致金属材料产生负热膨胀或者零热膨胀现象。高温容易破坏磁有序,磁体积效应诱导的零热膨胀大多发生在低温区,而价态转变有可能在非常高的温度发生,因此更有可能在价态转变的金属材料中实现高温零热膨胀。化学替代或成分改变会影响变价元素的稳定性,因此可以通过调控元素变价的温度及剧烈程度,实现金属材料的热膨胀调控。

1.4 复合作用

两相或者多相共存的零热膨胀材料主要依靠其中的负热膨胀相发挥作用,在适当界面结合力作用下,协同正热膨胀相和负热膨胀相的热膨胀性质,使负热膨胀相的体积收缩与正热膨胀相的体积膨胀相互抵消,整体呈现零热膨胀[14~16]。通过控制负热膨胀相和正热膨胀相的比例,可以实现双相或者多相合金热膨胀的有效连续调控。零热膨胀双相合金的研究不仅需要探讨两相热膨胀的协同机制,还需要考虑由两相共存产生的内应力以及原位析出反应引起的成分波动对负热膨胀相的磁性或价态转变产生的影响。界面在连接负热膨胀相和正热膨胀相时起着关键作用,它是热和机械载荷传递的必经通道。良好的界面结合除了可获得稳定的零热膨胀特性之外,还有利于同时实现优异的力学性能和高热导性能。

2 零热膨胀金属材料的分类

自1897年Invar合金被发现以来[5],人们对反常热膨胀材料的探索从未停止过,特别是探索新型零热膨胀金属材料以及揭示异常热膨胀机制成为此方向研究的热点。越来越多的单相负热膨胀材料被相继报道,对负热膨胀机理的理解也逐渐加深,使得在负热膨胀基体上调控出具有优异性能的宽温区零热膨胀金属材料成为可能。表1[14~46]分类列举了一些零热膨胀材料的热膨胀数据,图3为不同金属材料的零热膨胀温区。金属材料的零热膨胀主要是由磁性引起的,而磁有序一般在低温下才能稳定存在,可以观察到目前大部分金属材料的零热膨胀特性位于低温区,而零热膨胀材料在室温附近最有应用前景,因此开发在室温附近具有零热膨胀的金属材料具有重要意义。

表1   零热膨胀金属材料的热膨胀数据[14~46]

Table 1  Thermal expansion data of zero thermal expansion metallic materials[14-46]

MaterialTypeαl / (10-6 K-1)Temp. range / KRef.
Fe0.65Ni0.35Invar1.5193-373[17]
Zr0.8Nb0.2Fe2AFe21.43-470[18]
(Zr0.65Nb0.35)0.95Fe0.05Fe20.474-425[19]
Zr0.8Ta0.2Fe1.7Co0.30.21100-360[20]
Zr0.7Ta0.3Fe20.910-430[21]
Sc0.55Ti0.45Fe20.41a10-250[22]
Sc0.725Nb0.275Fe20.69108-264[23]
HfFe2.50.42a433-583[24]
Hf0.8Nb0.2Fe2.50.06a250-380[25]
Hf0.6Ti0.4Fe2.50.53a100-450[26]
Hf0.85Ta0.15Fe2C0.010.8a85-245[27]
Tb(Co1.9Fe0.1)RCo20.48123-307[28]
Gd0.25Dy0.75Co1.93Fe0.070.1610-275[29]
Gd0.5(Ho0.5Dy0.5)0.5Co21.35-220[30]
LaFe11.0Si2.0 hydrideLa(Fe, M)130.520-275[31]
LaFe10.3Al2.70.364.2-250[32]
LaFe10.6Si2.4-0.815-150[33]
Ho2Fe16CoR2Fe170.07a3-461[34]
Ho2Fe16Cr0.43a13-330[35]
Er2(Fe0.95Co0.05)14BR2Fe14B0.5a120-475[36]
MnCoGe0.99In0.01MnCoGe0.68200-310[37]
ErFe10V1.4Mo0.6RFe121.6120-440[38]
MnFe4Si3Mn5Si30.45b10-310[39]
Ni49.4Ti50.6Ti-based0.53b123-353[40]
Ni50.8Ti49.22.3b77-300[41]
Ti22Nb0.2b273-573[42]
xLFCS/39.7%Cu (volume fraction)Duplex alloy-0.21200-320[43]
LaFe54Co3.5Si3.351.10260-310[14]
Ho0.04Fe0.960.19b100-335[15]
LaFe10.1Cu0.5Si2.40.28185-250[44]
Er2Fe19B1.350.28100-500[16]
Fe2.75Co0.25PtB0.250.95360-560[45]
Hf0.8Ta0.2Fe2.50.352265-350[46]

Note:αllinear coefficient of thermal expansion (CTE); Temp. range—zero expansion temperature zone; superscript a—if the thermal expansion is anisotropic zero volume expansion, αl is estimated by 13αv (αv is volume CTE); superscript b—uniaxial zero thermal expansion; xLFCS—multicomponent material

新窗口打开| 下载CSV


图3

图3   不同金属材料零膨胀温区对比

Fig.3   Comparison of zero expansion temperature zone of different materials (Dashed line represents room temperature)


2.1 Invar合金

Invar合金(Fe0.65Ni0.35)在较宽温区内其尺寸基本不变,呈fcc结构,αl为1.5 × 10-6 K-1 (193~373 K)[5]。Invar合金的零热膨胀性能与其复杂的磁性相关,Fe0.65Ni0.35为铁磁结构,其磁化强度主要来源于Fe原子,Ni对磁性的贡献非常小,升温过程中大体积的有序铁磁结构转变为小体积的无序顺磁结构,磁体积效应产生的负热膨胀与晶格非简谐振动产生的正热膨胀相互抵消,从而产生宽温区零热膨胀现象[9]。Weiss[47]提出了描述Invar异常的第一个模型“2γ-sate”,该模型认为Fe在γ相中可以具有2种不同原子体积的磁态:低磁矩小体积(γ1)态和高磁矩大体积(γ2)态。当温度升高时,大体积γ2态转变为小体积γ1态,以补偿热振动引起的正常热膨胀。近期Lohaus等[48]从热力学角度揭示了Invar机理,他们将0~3 GPa压力范围等效于Invar合金变温过程的零热膨胀温区,通过实验测定自旋和声子熵,从而分别给出了磁性和原子振动产生的热膨胀分量,发现在磁转变之前,这2种贡献都随着压力的增加而增加,但是它们的符号相反。自旋-声子相互作用导致声子熵的压力依赖性更好地对抗了磁熵随压力的非线性趋势,使磁性和原子振动引起的热膨胀分量刚好相互抵消,从而产生了零热膨胀,因此可以认为Invar效应并不仅仅是磁性引起的,而是声子与自旋相互耦合作用的结果,如图4[48]所示。Invar合金不仅有良好的热膨胀性能,还具有较优异的机械加工性能。Invar合金是当前应用最广泛的零热膨胀金属功能材料,在Fe-Ni、Fe-Pt[49]、Fe-Pd[50]和Fe-Cr[51]等合金中都发现了Invar效应。

图4

图4   Invar合金的热膨胀、磁结构以及热力学模拟分析[48]

Fig.4   Calculated spin configurations at Fe (orange) and Ni (blue) atoms in fully ordered ferromagnetic states (0 K), ambient states, and paramagnetic states (The size of the arrow is proportional to the calculated magnetic moment)[48] (a), the relationship between the magnetization of Invar alloy and the pressure (P)[48] (b), comparison of linear expansion of Invar alloy, Fe, Cu and Al (Δl / l0—relative length variation) (c), change of phonon entropy and magnetic entropy of Invar alloy with pressure (Sph—phonon entropy; ΔSmag—magnetic entropy change)[48] (d), and change of the sum of phonon entropy and magnetic entropy (ΔSph—phonon entropy change)[48] (e)


2.2 AFe2(A = ZrNbHfTaScTi)型金属材料

ZrFe2是一种立方结构的铁磁性金属间化合物,在整个温度范围内表现出正热膨胀,作者研究团队[18]采用Nb部分替代Zr,使ZrFe2的热膨胀得到有效调控,并且随着替代量增大,在磁转变温度以下正热膨胀会转变为负热膨胀,其中Zr0.7Nb0.3Fe2αl为-2.14 × 10-6 K-1 (209~358 K),特别地,在Zr0.8Nb0.2Fe2中可以实现宽温区的各向同性零热膨胀(αl为1.4 × 10-6 K-1,3~470 K)。(Zr, Nb)Fe2的异常热膨胀与磁结构转变密切相关,ZrFe2由正热膨胀转变为零热膨胀是由于用小半径的Nb替代Zr加快了磁转变速率,使磁体积效应刚好与声子非简谐振动产生的正热膨胀相互抵消。高压中子实验进一步证实了磁转变速率可控制(Zr, Nb)Fe2热膨胀变化,如图5a[18]所示。近期,Sun等[19]以Zr0.65Nb0.35Fe2的负热膨胀材料为基体,利用过量Fe替代Zr/Nb位,高温淬火得到单相零热膨胀材料(Zr0.65Nb0.35)0.95Fe0.05Fe2 (αl = 0.47 × 10-6 K-1,4~425 K),如图5b[19]所示。Li等[20]通过对Fe位和Zr位同时掺杂得到Zr0.8Ta0.2Fe1.7Co0.3 (ZTFC)的零热膨胀耐腐蚀金属材料(αl = 0.21 × 10-6 K-1,100~360 K)。Cao等[21]通过控制退火温度使得Zr0.7Ta0.3Fe2以立方单相形式存在,并得到了优异的零热膨胀特性(αl = 0.9 × 10-6 K-1,10~430 K),如图5c[21]所示,其本质也都是调控磁转变速率及磁转变温度,从而控制热膨胀的变化。

图5

图5   AFe2 (A = Zr、Nb、Hf、Ta、Sc和Ti)体系零热膨胀性能[18,19,21,22,24,26]

Fig.5   Zero thermal expansion properties of AFe2 (A = Zr, Nb, Hf, Ta, Sc, and Ti) systems[18,19,21,22,24,26]

(a) comparison of macroscopic linear expansion of Zr0.8Nb0.2Fe2, Fe0.64Ni0.36, and Fe[18]

(b) temperature dependence of cell parameters for neutron diffraction and synchrotron radiation analysis of (Zr0.65Nb0.35)0.95Fe0.05Fe2 (ZNFF)[19] (SXRD—synchrotron X-ray diffraction, NPD—neutron powder diffraction, a—cell parameter, αa —thermal expansion coefficient of crystal in a-axis direction)

(c) variation of cell parameters of Zr0.7Ta0.3Fe2 with temperature (Δa—change of a,ZTE—zero thermal expansion, FM—ferromagnetic, AFM—antiferromagnetic)[21]

(d) relative cell volume of (Sc, Ti)Fe2 varies with temperature when x = 0 (PTE—positive thermal expansion), x = 0.45 (ZTE), and x = 0.6 (NTE—negative thermal expansion)[22]V / V—relative cell volume variation; CMVE—traditional magnetic volume effect; UMVE—unconventional magnetic volume effect)

(e) temperature dependence of unit cell volumes for HfFe2 + δ (δ = 0.3, 0.5, and 0.6)[24] (LTE—low thermal expansion)

(f) dilatometer thermal expansion of TiFe2 and Hf0.6Ti0.4Fe2 + x (x = 0, 0.5, and 1.3)[26]


ScFe2和TiFe2均为MgZn2型六方相体积正热膨胀材料,因其原子半径差异较小并且结构相符,因此可以在Sc1 - x Ti x Fe2 (x = 0.0~1.0)全区间内进行替代得到单一六方相。其中ScFe2为铁磁结构,TiFe2为反铁磁结构,由此随着替代比例不同Sc1 - x Ti x Fe2展现出丰富的磁结构转变[52]。作者研究团队[22]通过调整替代的Ti含量,发现(Sc1 - x, Ti x)Fe2的热膨胀发生了由正到负的转变,其中Sc0.4Ti0.6Fe2的体积膨胀系数αv = -28.36 × 10-6 K-1 (125~205 K),特别在x = 0.45时,调控出了宽温区的体积零热膨胀(αv = -1.24 × 10-6 K-1,10~250 K)。经过磁性测试以及中子衍射分析发现,Sc1 - x Ti x Fe2的异常热膨胀是由铁磁1到铁磁2 (FM1-FM2)转变造成的,这个过程中占据Wyckoff位6h (x', 2x', 1/4)的Fe原子(用Fe(6h)表示,以下类似)的自旋磁矩减小但磁矩方向未发生改变,且晶胞参数a (b)的减小与Fe(6h)-Fe(6h)的间距存在对应关系,并用热膨胀的实验值(ωexp)减去声子对热膨胀的影响(ωnm)表示了铁磁矩减小对热膨胀的贡献,如图5d[22]所示。也有学者[23]通过Nb替代Sc位,在Sc0.725Nb0.275Fe2中实现了体积零热膨胀(αv = -0.69 × 10-6 K-1,108~264 K)。

HfFe2是多相共存的各向异性正膨胀材料,有学者通过Ta/Ti/Nb元素部分替代Hf位实现了正热膨胀到负热膨胀的转化。例如(Hf, Ta)Fe2[53]、(Hf, Ti)Fe2[54]、(Hf, Nb)Fe2[55]等都存在负热膨胀现象,作者研究团队[24]通过Fe过量的方法调控HfFe2 + δ (δ为偏离原始基体HfFe2相的Fe的添加量,0 ≤ δ ≤ 0.8)磁性,实现从负热膨胀-零热膨胀-低热膨胀的连续转变。其中,负热膨胀材料HfFe2.3在418~523 K的αv为-5.11 × 10-6 K-1,零热膨胀材料HfFe2.5在433~583 K的αv为1.25 × 10-6 K-1,低热膨胀材料HfFe2.6在298~613 K的αv为 5.73 × 10-6 K-1。通过同步X射线衍射解析了HfFe2 + δ 的相组成以及晶体结构,其中HfFe2在室温下为C14和C15 Laves混合相,随着Fe含量的增加HfFe2 + δ 稳定在C14六方Laves相结构,过量的Fe占据Hf(4f)位,由此可以认为HfFe2 + δ 的热膨胀变化是由强磁性Fe原子取代非磁性原子Hf从而改变其磁性造成的。磁性测试以及中子衍射分析发现,Fe原子的总磁矩对温度的一阶导数与晶胞参数a (b)对温度的一阶导数随温度的变化有着相同的趋势,表明HfFe2 + δ 的面内收缩是由Fe原子总磁矩减小造成的。根据Debye-Grüneisen方程定量展现了磁性变化造成的HfFe2.5的零热膨胀,如图5e[24]所示。近期Dong等[25]在Hf0.8Nb0.2Fe2负热膨胀的基础上,通过Fe过量掺杂增强了铁磁交互作用,得到了六方单相零热膨胀材料(Hf0.8Nb0.2Fe2.5αl = 0.06 × 10-6 K-1,250~380 K)。

成分均匀性对于材料的影响是巨大的,微小成分的偏差可能会给材料性能造成很大的影响。在负热膨胀的研究中,大多倾向于发掘单相的均质材料,异质结构少有研究。Lin等[26]通过设计材料化学异质性,在(Hf, Ti)Fe2.5体系中实现了热膨胀的调控,并在Hf0.6Ti0.4Fe2.5中得到了非均质的宽温区零热膨胀材料(al = 0.53 × 10-6 K-1,100~450 K),如图5f[26]所示。采用同步辐射以及中子衍射分析等实验手段对(Hf, Ti)Fe2进行研究,发现其存在分裂的不对称峰,可以分解为两相。而加入过量Fe后,在(Hf, Ti)Fe2.5中,分裂峰消失,峰形趋于对称,展现出准单相行为。电子探针显微分析以及元素分析结果表明,微区Hf、Ti成分存在周期连续性波动。这种周期性分布使得(Hf, Ti)Fe2.5异于(Hf, Ti)Fe2和TiFe2的磁性变化。经过定量设计富Hf相与富Ti相样品,研究了浓度调节热膨胀的机制,发现富Hf相与富Ti相呈趋势相反的热膨胀性能,由此拟合的平均热膨胀与Hf0.6Ti0.4Fe2.5相一致,证明了化学异质结构在负热膨胀调控中的可行性。

自(Zr, Nb)Fe2的Invar效应被发现以来,人们对Laves体系进行了系统的研究[18,56],包括负热膨胀Laves相新材料的探索以及对已有的负热膨胀体系进行调控得到性能优异的零热膨胀材料。由于Laves体系负热膨胀效应与磁性直接相关,因此对于Laves相体系的磁性调控就显得尤为重要。Xu等[27]发现通过在(Hf, Ta)Fe2中引入间隙原子C可以有效地调控磁结构,进而影响材料的热膨胀性能,最终在Hf0.85Ta0.15Fe2C0.01中实现了宽温区零热膨胀。通过对不同Ta含量替代的(Hf, Ta)Fe2与(Hf, Ta)Fe2C0.01进行实验研究、形成机理分析和理论计算,证明了C的引入可以稀释铁磁耦合,使得其更容易向反铁磁转变,而(Hf, Ta)Fe2的负热膨胀正是由铁磁向反铁磁转变引起的,因此C的引入对于热膨胀的调控起促进作用。基于磁性和晶体结构之间的强相关性,间隙原子的引入不失为一种方便、有效的优化热膨胀的方法。

2.3 RCo2(R =稀土元素)金属材料

化学替代是一种常见的热膨胀调控方法。TbCo2是一种负热膨胀磁性金属材料,在低温下为三方(R3¯m)亚铁磁结构,随着温度的升高会发生亚铁磁到顺磁转变,同时晶体结构向着立方相(Fd3¯m)转变,其间伴随着晶胞参数的变化。TbCo2在晶型转变时伴随着较大的体积收缩,但其发生在低温区并且存在于较窄的温区内,这非常不利于实际应用[57,58]。作者研究团队[28]发现,采用原子半径较大的Fe替代Co,可以实现热膨胀调控,其中Tb(Co1.9Fe0.1)在较宽温度范围内(123~307 K)实现了零热膨胀(αl = 0.48 × 10-6 K-1)。结合同步X射线衍射、中子粉末衍射和宏观磁性能测试等手段发现,Tb局域的4f磁矩与Co/Fe3d磁矩之间的耦合作用决定了Tb(Co, Fe)2的磁性,Fe替代Co后增强了磁矩,从而提高了磁转变温度,因此拓宽了Tb(Co, Fe)2的负热膨胀或零热膨胀工作温区,如图6a~c[28]所示。

图6

图6   RCo2 (R = Tb、Gd和Dy)体系的磁结构、晶体结构以及热膨胀调控[28,29]

Fig.6   Magnetic structure, crystal structure, and thermal expansion regulation of RCo2 (R = Tb, Gd, and Dy) systems[28,29]

(a) crystal and magnetic structures of Tb(Co1.9Fe0.1) intermetallic compound at 10 K[28]

(b) Tb(Co1 - x Fe x)2 macroscopic linear expansion curves[28]

(c) comparison of intrinsic volume expansion and macroscopic linear expansion[28]

(d) crystal structure of Gd0.25Dy0.75Co1.93Fe0.07 (GDCF)[29]

(e) linear thermal expansion of Gd x Dy1 - x Co2 and GDCF (Inset shows Δl / l0 of GdCo2 (x = 1) in the high temperature region)[29]


DyCo2为MgCu2型Laves相,其在Curie温度(TC = 137 K)以下表现出负热膨胀,且在较窄温区内表现出强负热膨胀(相对长度变化率Δl / l0≈ -0.08%,120~141 K)。GdCo2为正膨胀材料(αl = 5.88 × 10-6 K-1,100~404 K),有着较低的负热膨胀系数和较高的磁转变温度(TC = 404 K)。Hu等[29]在DyCo2的基础上,通过成分设计得到了Gd0.25Dy0.75Co1.93Fe0.07 (GDCF)的各向同性零热膨胀材料(αl = 0.61 × 10-6 K-1,98~270 K),如图6de[29]所示,通过宏观磁性测试得到RCo2的热膨胀异常是由晶格与磁相变耦合造成的,并进一步研究了其磁熵的变化,发现Gd的引入将DyCo2的一阶磁相变转变为二阶磁相变,磁熵变化与热膨胀有着显著的对应关系。这种通过将剧烈的一阶磁相变转化为平缓的二阶磁相变进而控制其热膨胀的方法,为探索磁性零热膨胀材料提供了一种行之有效的措施。除此之外,在RCo2体系中,Hao等[30]通过多稀土共掺杂,在Gd0.5(Ho0.5Dy0.5)0.5Co2中实现了宽温区零热膨胀(αl ≈ 1.3 × 10-6 K-1,5~220 K)。其中,HoCo2和DyCo2为低温负热膨胀材料,其负膨胀来源于磁一级相变造成的晶格畸变[59,60]。有研究[61]表明,随着R元素的增多,一级相变造成的晶格畸变会随之削弱。GdCo2为正热膨胀材料,并且在TC处存在二级相变,其对应着较小的晶格畸变。因此,通过多稀土替代可以使得磁相变可控,同时影响晶格畸变,实现超低热膨胀。

2.4 La(Fe, M)13(M = SiAl)金属材料

NaZn13型La(Fe, M)13 (M = Si和Al)基化合物因其各向同性和显著的负热膨胀、磁热效应、较高的导电/导热性能和优异的力学性能而被认为是有前景的负热膨胀材料之一[44,62~65]。研究[31]发现,La(Fe, Si)13中La原子间隙容易被H、C和B等小原子占据,这会导致Curie温度向室温移动,并且使铁磁相在更高温度下存在,这为实现具有宽工作温度窗口的零热膨胀提供了机会。间隙原子改变了Fe—Fe距离,进而影响磁性能及其耦合的热膨胀。Li等[31]通过电解氢化法制备了La(Fe, Si)13氢化物,其中LaFe11.0Si2.0H y 在20~275 K范围内αl是0.5 × 10-6 K-1,比氢化前更接近零热膨胀,并且工作温区从15~175 K拓宽到20~275 K,如图7a~d[31]所示,相较于其他类别的零热膨胀材料是很少见的,在许多科学和技术领域都具有巨大应用潜力。Al的替代会有效降低La(Fe, M)13的宏观磁转变温度,影响磁性原子耦合作用,从而对热膨胀产生直接影响。对于x = 2.5的La(Fe13 - x Al x)样品,其在5~250 K范围内的平均αl为-0.78 × 10-6 K-1,如图7cf[32]所示。因此,该类材料可以应用于对温度敏感的设备和器件中。除此之外,Wang等[33]通过调节La(Fe13 - x Si x)中Si的含量来调控热膨胀,在x = 2.4时,得到了低温零热膨胀材料(αl = -0.8 × 10-6 K-1,15~150 K)。

图7

图7   La(Fe, M)13 (M = Si, Al)型金属材料热膨胀性能及宏观磁性[31,32]

Fig.7   Thermal expansion properties and macroscopic magnetic properties of La(Fe, M)13 (M = Si, Al) type metal materials[31,32]

(a, b) thermal expansions of LaFe13 - x Si x (x = 1.5, 2.0, 2.4) (a) and LaFe13 - x Si x hydrides (x = 1.5, 2.0, 2.4) (b)[31]a / a300 K—rate of change of cell parameter relative to 300 K, ΔT—temperature difference)

(c, d) macroscopic magnetisms of LaFe13 - x Si x (c) and LaFe13 - x Si x hydrides (d)[31] (Inset in Fig.7d shows the TC curves for original and hydrogenated LaFe13 - x Si x sample)

(e) thermal expansion of LaFe13 - x Al x (x = 2.5, 2.7)[32] (SS304—304 stainless steel, ΔL / L(300 K)—linear thermal expansion reative to 300 K)

(f) macroscopic magnetism of LaFe13 - x Al x (x = 1.8, 1.9, 2.1, 2.3, 2.5, 2.7)[32] (PM—paramagnetic)


2.5 R2Fe17 型金属材料

R2Fe17是一种典型的负热膨胀金属间化合物,其中Ho2Fe17为磁有序驱动的负热膨胀材料[66~68]。Cao等[34]通过实验发现Co替换Fe位后,磁有序温度显著增加,由此通过调整Fe含量来定量调控Ho2(Fe, Co)17的磁性,最终改善了热膨胀性能。其中Ho2Fe16Co在磁转变温度以下展现出宽温区零热膨胀性能(αl = 0.07 × 10-6 K-1,3~461 K),Ho2Fe15Co2展现出低热膨胀性能(αv = 7.5 × 10-6 K-1,3~590 K)。通过第一性原理,对Ho2Fe17的电子结构进行解析,并使用局域磁矩无序方法对顺磁状态下的磁无序进行建模,发现磁有序和磁无序时3d电子态密度存在明显差异。磁无序时Fe态密度的带宽很宽,延伸到Fermi能级。磁有序时Fermi能级主要位于Fe3d多带顶部,多带完全被3d电子占据,从而显示出较高的磁矩。为了平衡由于能带分裂引起的能量变化,晶胞参数随着局部磁矩的增加而变化。磁有序化对应着3d轨道少带中的非键轨道减弱和多带中的反键轨道增强,因此会削弱3d电子巡游性,使得Fe—Fe间距变大,从而在铁磁-顺磁转变时对应着晶胞减小,产生负热膨胀。当Co替代Fe后,多带里其他反键轨道的消失补偿了磁有序带来的多带反键轨道的增加,磁体积效应因磁有序对晶格的作用减小而削弱,因此随着Co的替代,Ho2(Fe, Co)17的热膨胀会呈现出由负到正的变化,如图8[34]所示。除此之外,也有学者[35]通过用Cr来替代Fe位,在Ho2Fe16Cr中实现了零热膨胀(αv = 1.3 × 10-6 K-1,13~330 K)。

图8

图8   Ho2(Fe, Co)17的热膨胀性能以及热膨胀调控机制[34]

Fig.8   Thermal expansion properties of Ho2(Fe, Co)17 and its regulation mechanism[34]

(a) volumetric thermal expansion of Ho2(Fe, Co)17V—relative volume variation, SIVsuper Invar)

(b) stability of zero expansion of Ho2Fe16Co (ΔT1—100-208 K, ΔT2—208-377 K, ΔT3—377-416 K) (c, d) magnetic ordered densities of state (DOS) of Ho2Fe17 (c) and Ho2Fe15Co2 (d) (E—electronic energy level, FIM—ferrimagnetic, DLM—disordered local moment) (e) changes of Fe magnetic moment and cell volume (V) of Ho2Fe16Co at 6g (MFe/Co—magnetic moment of Fe/Co atoms, T—temperature, μB—Bohr magnetron) (f) contribution of the magnetic moment (MFe) and magnetic order of the Fe sublattice to the cell volume (VM) (VM(T)—contribution of magnetic ordering to the unit cell volume, |Σ MFe|—magnetic moment of Fe sublattice. Inset in Fig.8f shows the |Σ MFe| as a function of Co content)


2.6 R2Fe14B型金属材料

R2Fe14B作为永磁材料已被广泛应用。其自发磁致伸缩性能早在1987年就被报道,之后发现其负热膨胀特性与磁性相关[69~71]。Er2Fe14B具有复杂的磁结构,在低温时为亚铁磁结构,Er、Fe的磁矩随着温度变化存在自旋重取向,其中Er的磁矩倾向为面内各向异性,而Fe为轴向各向异性,在5 K时Fe磁矩与Er磁矩反向排列且与c轴成80°夹角,随温度升高磁矩向c轴旋转,在达到自旋重取向温度(TSR)时沿着c轴排列。Co的取代使R2Fe14B的晶胞参数减小,增加了相邻原子的磁交换积分和自旋耦合能力,导致TC升高并且磁矩随温度变化趋于平缓。作者研究团队[36]通过Co的掺杂调控磁性,来获得相应的热膨胀性能,磁贡献与磁矩变化速率相关联,其中Er2(Fe1 - x Co x)14B在x = 0.05时展现出优异的零热膨胀性能(αv = 1.5 × 10-6 K-1,120~475 K)。

2.7 MnCoGe基金属材料

MnCoGe是由相变导致的负热膨胀化合物,其负热膨胀是由奥氏体(Ni2In型六方空间群P63/mmc)到马氏体(TiNiSi型正交空间群Pnma)结构转变,其间伴随着晶胞参数的巨大转变,晶胞体积负膨胀率(ΔV / V)高达3.9%左右。很多学者[72~74]对MnCoGe基化合物进行了详细研究,一方面将其磁性与相变结合研究其磁热与压热性能[75~77],另一方面针对其巨大负热膨胀性能进行有效调控。例如,通过环氧树脂黏结引入残余应力、元素掺杂替代引入晶格应力、球磨细化晶粒尺寸、非化学计量替代进行化学改性、非晶化控制结晶度和调控马氏体转变等[72,73,78],对于其负热膨胀温区和热膨胀系数调控都有着明显的效果。Shen等[37]通过调整球磨时间来控制非晶化程度,由于球磨带来的残余应力和原子缺陷进一步影响了马氏体的结构转变,实现了MnCoGe0.99In0.01由黏结颗粒巨大负膨胀(αl = -94.7 × 10-6 K-1,192~310 K)到零热膨胀(0.3~1 μm,αl = 0.68 × 10-6 K-1,200~310 K)的调控。

2.8 RFe12 型金属材料

通常磁性金属基负热膨胀体系的异常热膨胀被限制在磁转变温度以下,并且温区较窄[29,79]。为使温区进一步拓宽,大多采用过渡、稀土磁性原子去替代基体的磁性原子,从而改变磁交互作用以及总磁矩来进行调控。Li等[38]用非磁性原子Mo取代Fe、V位,研究了V、Mo对ErFe10V2 - x Mo x 磁结构的影响,并在ErFe10V1.4Mo0.6中实现了宽温区零热膨胀(αv = 4.81 × 10-6 K-1,120~440 K)。通过对其晶体结构进行中子衍射测试解析发现,当x < 0.6时,Mo只占V8i位,而当x > 0.6时,Mo会进一步占据Fe8j和Fe8f位。随着Mo替代量的增加线膨胀持续降低,在x = 0.4和0.6时达到最小值。变温中子衍射和X射线吸收近边结构光谱分析发现,Fe与Mo存在价电子转移,在x ≤ 0.6时,铁磁矩会相应减小,表明Mo的替代减弱了Fe3d原子的局域磁矩和磁交互作用,并降低磁转变温度。因此,自发体积磁致伸缩被限制在较窄温区,从而减小了热膨胀系数。

2.9 Mn5Si3 型金属材料

Mn5Si3为体积正热膨胀化合物,是轻质磁性材料,由于其具有丰富磁热效应[80]、反常Hall效应 [81]而被广泛研究。形状记忆合金可以通过轧制调整马氏体晶体学取向,从而定制热膨胀,受此启发,Yu等[39]通过调节晶体学取向和磁体积效应来实现二维零热膨胀行为的途径。在MnFe4Si3中获得了宽温度区间(10~310 K)的具有αl = 0.45 × 10-7 K-1的二维零热膨胀合金。同步加速器X射线衍射、中子衍射、电镜和磁性测试的结果表明,这种零热膨胀行为由Wyckoff位6g位置上的Fe在a-b面内的磁矩以及块体织构共同决定。

2.10 钛基合金

钛基合金由于其出色的物理性能而被广泛应用于医疗、航空等领域。自Kainuma等[82]首次报道了冷轧对CuZnAl形状记忆合金热膨胀的影响以来,对于钛基形状记忆合金的热膨胀调控也开展了一系列的研究[83~85]。Ahadi等[40]通过冷轧制备的纳米结构NiTi板可实现热膨胀系数由正(αl ≈ 2.1 × 10-5 K-1)到负(αl ≈ -1.1 × 10-5 K-1)的大范围调控,并且在沿着与轧制方向(RD)成33.5°夹角方向可获得类Invar合金的零热膨胀性能(αl ≈ -5.3 × 10-7 K-1),如图9a[40]所示。这种反常热膨胀行为是由微观组织引起的,也就是各向同性的奥氏体相(B2)和残余变形诱导的各向异性的马氏体相(B19')热膨胀耦合的结果。通过轧制可以改变马氏体相的负热膨胀取向从而在一定范围内实现热膨胀调控,其中零热膨胀性能是奥氏体相的正膨胀与残余马氏体沿与RD成33.5°夹角方向的负热膨胀相互抵消的结果。由此建立了简单的混合模型,考虑了B2和B19'晶格的热膨胀,以及织构对热膨胀耦合的影响,很好地解释了TiNi形状记忆合金的异常热膨胀行为。

图9

图9   钛基形状记忆合金各向异性热膨胀以及循环性能[40~42]

Fig.9   Anisotropic thermal expansion and cyclic properties of titanium-based shape memory alloys[40-42]

(a) evolution of macroscopic strain with temperature of rolled 60% (thickness reduction rate) Ti50.6Ni49.4 alloy sheet along RD, 22.5°, 33.5°, 45°, 67.5°, and TD after annealing for 60 min at 523 K[40] (RD—rolling direction, TD—transverse direction)

(b) Ni50.8Ti49.2 alloy through three steps rolling (CroR-15%-10%-5%: the thickness of the first rolling direction is reduced by 15%-the thickness in the vertical direction from the first rolling direction is reduced by 10%-thickness is reduced by 5% along the first rolling direction) to a thickness of 30% of the total thickness after the internal macroscopic thermal expansion change[41] (CroR—cross rolling, TE—thermal expansion)

(c) Ti22Nb CR (cold-rolled) plate along the rolling direction in eight cycles (cycle 01 Tmax (maximum temperature) = 350 oC, thermomechanical analyzer measurements were performed in cycle 02-08 at Tmax = 300 oC)[42] (Inset shows the transmission Kikuchi diffraction (TKD) band contrast (BC) + inverse pole figure (IPF) map inside a primary martensite lath in the sample heating to 350 oC)


形状记忆合金经过单向轧制后可在单一方向得到宏观的宽温区零热膨胀性能[86,87]。Li等[41]通过可控交叉轧制(CroR)方法实现了多晶NiTi板的面内宽温区近零热膨胀性能。结果表明,经过RD15% (第一次轧制方向厚度减少15%)、轧制方向的垂直方向(TD)10% (与第一次轧制方向的垂直方向厚度减少10%)和RD5% (沿第一次轧制方向厚度减少5%)三步轧制路径的Ni50.8Ti49.2板,其面内热膨胀系数可降至接近于零的水平(-2.7 × 10-6~3.0 × 10-6 K-1),温区可达223 K,如图9b[41]所示。其αl比纯NiTi板小1个数量级,与商用Fe-Ni Invar合金(2.0 × 10-6 K-1)相当。通过原位中子衍射和混合规则理论模型发现,在交叉轧制得到的纳米结构NiTi板中,由于纤维织构的B19'相在冷却(加热)过程中不断形成(消失),从而导致面内低热膨胀,补偿了织构B2和B19'聚集体的面内正热膨胀,这种补偿机制也可用于实现其他形状记忆合金的面内低热膨胀。

TiNb合金的异常热膨胀与正交α''马氏体的各向异性热膨胀有关[88,89]。Bönisch等[88]通过设计不同Nb含量钛合金,研究了Nb含量对α''马氏体的晶体结构、相转变及各向异性热膨胀的影响,并分析了Nb含量与各向异性热膨胀的关系,在Ti36Nb合金中得到了具有显著各向异性线膨胀的α''马氏体(晶体沿a轴方向的热膨胀系数αa = 163.9 × 10-6 K-1,晶体沿c轴方向的热膨胀系数αc = 24.4 × 10-6 K-1,晶体沿b轴方向的热膨胀系数αb = -95.1 × 10-6 K-1),为TiNb合金单轴热膨胀定制提供基础。通过轧制可以使其负热膨胀方向定向分布,但是调控热膨胀仅限于单相马氏体温度场,因此需要避免马氏体向奥氏体的转变,测试最高温度(Tmax)应低于马氏体向奥氏体转变温度。Wang等[42]证明了在Ti22Nb合金中由扩散形成的纳米α''马氏体不仅可以调节热膨胀,并且与马氏体冷加工相比,大大拓宽了定制热膨胀的温度窗口(图9c[42])。通过原位X射线衍射以及中子衍射等技术手段,阐明了由扩散形成的纳米正交马氏体(αiso)在热循环过程中的相转变、相含量的变化,并解决了马氏体相与母相的结晶学关系,这些发现为设计具有较大工作温度范围的低热膨胀钛合金提供了新的途径。

2.11 零热膨胀双相合金

负热膨胀材料因其独特的热膨胀性质可以有效调控金属材料的高热膨胀,作为热膨胀补偿剂,合成性能优异的低热膨胀甚至零热膨胀复合材料。近几十年来,负热膨胀材料发展迅速,种类逐渐丰富,双相零热膨胀材料种类也随之增多。对于单相零热膨胀化合物来说,严格的晶格-自旋-轨道耦合[9,48,90]已经限制了其组分的调整,要想在保证其热膨胀性能的同时提升力学性能是极其困难的。而绝大多数单相零膨胀合金往往表现出脆性,而不具备加工性能,如Laves相[18,22]、La(Fe, M)13[31,91]R2Fe17[34,35]等。由此设计的具有韧性可加工的双相零热膨胀合金在应用方面显得尤为重要。

巨大负热膨胀材料作为铜基复合材料的增强体可以有效补偿Cu的正热膨胀,但通常存在负热膨胀温度范围窄的缺点,作者研究团队[43]设计了一种由具有相邻负热膨胀温区的La(Fe, Co, Si)13组成的多组分材料(xLFCS)作为金属基复合材料(MMCs)的增强体,这样可以扩大温度范围,将其作为增强材料加入Cu基体中,可以有效降低复合材料整体的热膨胀(图10[43])。将多组分La(Fe, Co, Si)13材料组装后作为MMCs的增强体,制备了热膨胀性能优异的xLFCS/Cu复合材料,该复合材料的热膨胀系数可灵活调节,通过增加Cu的体积分数,热膨胀系数由负变正。特别地,xLFCS/39.7%Cu (体积分数)样品实现了宽温度范围(200~320 K)的零热膨胀(αl = -0.21 × 10-6 K-1)。

图10

图10   xLFCS/Cu金属基复合材料的多组分增强体设计以及热膨胀性能[43]

Fig.10   Multi-component reinforcement designs and thermal expansion performances of xLFCS/Cu metal matrix composites

(a, b) enhanced metal matrix composites (MMC) with a single NTE material (a) and a multi-component NTE material (b)

(c, d) linear thermal expansions of LaFe10.5Co1.0Si1.5 (c), and six compositions of LaFe11.5 - x Co x Si1.5 (dashed line) and xLFCS (solid line) (d)

(e, f) MMC reinforced with a single NTE material (e) and a multi-component NTE material (f)


软硬交叉结构是提升双相合金力学性能的有效手段[92,93],然而第二相的引入要同时考虑界面反应、热膨胀稳定等难题。Yu等[14]在La(Fe, Co, Si)13室温负膨胀材料中原位析出α-Fe,通过对两相组分进行调节,制备出室温各向同性负热膨胀、零热膨胀和低热膨胀具有优异加工性能的双相合金,如图11ab[14]所示。通过化学分配策略来构建最佳组合的异质结构,设计出了LaFe54Co3.5Si3.35室温各向同性零热膨胀双相合金(αl = 1.10 × 10-6 K-1,260~310 K),兼具超高的韧性((277.8 ± 14.7) J/cm3)。同步辐射X射线衍射结果揭示物相组成为bcc结构α-Fe (Fe-Co-Si,α相)和fcc结构La(Fe, Co, Si)13 (L相)。采用透射电子显微镜、三维原子探针和原位中子衍射分析了界面组成、晶格适配以及加载过程中的组织演变,对材料协同机制、应力传递和亚结构的协调变形进行了深入解析,为可加工零热膨胀合金应用提供了可行思路。

图11

图11   不同双相合金体系的热膨胀调控[14~16,45,94]

Fig.11   Thermal expansion control of different biphase alloy systems[14-16,45,94]

(a) zero thermal expansion dual-phase alloy obtained by synergistic combination of negative thermal expansion L phase (La(Fe, Co, Si)13) and positive thermal expansion α phase (α-(Fe, Co, Si)) (αCalc.—calculated S-3 ZTE (empty circle point line) is derived from L-phase and α phase thermal expansions)[14]

(b) thermal expansion behavior of LaFe0.939x Co0.061x Si0.0583x (x = 37.5, 47.5, 57.5, and 67.5, designated as S-1, S-2, S-3, and S-4, respectively)[14]

(c) macroscopic linear expansion of samples labeled S-3 (x = 0.03) to S-9 (x = 0.09) in Ho x Fe1 - x with x = 0.03, 0.04, 0.05, 0.07, and 0.09[15]

(d) linear thermal expansion curves of samples in (LaFe10.8CoSi1.2)100 - y -Cu y alloys where y = 0, 15, 25, 35, and 45[94]

(e) thermal expansion of Er2Fe14 + x B1 + 0.07x alloy compared to pure iron[16]

(f) cyclic thermal expansion properties of Fe2.85Mn0.15PtB0.25[45]


由二元相图得到R2Fe17可以与Fe存在双相共存区,并且可以通过共晶反应得到双相合金。Yu等[15]利用这一特性,采用共晶反应方法制备双相合金,克服了零热膨胀与塑性之间的矛盾。他们将少量Ho加入到纯Fe中,合成出一种零热膨胀双相合金Ho0.04Fe0.96 (αl = 0.19 × 10-6 K-1,100~335 K),如图11c [15]所示。该合金呈现出半共格界面的层状双相组织,这种组织不仅可以调节热膨胀行为,还能大幅提高合金的力学性能和热稳定性。该双相合金兼具宽温区的双轴向零热膨胀和较高力学性能,而且制备成本很低,有巨大的应用潜力,该研究提供了一种利用共晶反应制备高性能零热膨胀合金的策略。

近期,以La(Fe, Si)13为基体,通过双相来补偿其负热膨胀得到力学性能优异的零热膨胀材料也取得了一系列进展。Liu等[44]通过Cu掺杂得到LaFe10.6 - x Cu x Si2.4材料,X射线衍射分析发现,Cu的掺杂可以原位析出1∶13相、1∶1∶1相和α-Fe相,其中1∶13相作为负热膨胀相,1∶1∶1和α-Fe相作为正热膨胀相可以补偿其负热膨胀,达到调节材料整体热膨胀性能的目的。最终在LaFe10.1Cu0.5Si2.4中实现了优异的零热膨胀(αl = 2.8 × 10-7 K-1,185~250 K)。另一项研究以(LaFe10.8CoSi1.2)100 - y-Cu y 进行双相设计,不仅在Cu45成分中实现了接近零的负热膨胀,并且LaCu2第二相与La(Fe, Co, Si)13相为半共格结构,可能导致了两相的协同变形,如图11d[94]所示。实验表明,引入的第二相强化可以使材料的力学性能以及疲劳寿命大幅提升。

Er2Fe14B是典型的各向异性宽温区负热膨胀材料,是制备铁基双相零热膨胀合金良好的基体。Yu等[16]通过固相反应(ErFe10 + BGBs → Er2Fe14B + α-Fe;GBs代表晶界)设计了α-Fe与Er2Fe14B负热膨胀相共存的双相合金,降低了Fe基体的热膨胀。并且通过组分、结构设计消除了基体的晶体织构,得到了各向同性的宽温区零热膨胀性能(αl = 0.28 × 10-6 K-1,100~500 K),如图11e[16]所示。通过热处理使得B原子由前驱体ErFe10的晶界处向晶内扩散,形成了“plum pudding”的微结构(即Er2Fe14B为pudding,α-Fe为plum,代表位于晶界的α相和分散在晶内的亚微米尺寸的α相),α-Fe均匀分布在Er2Fe14B的晶界和晶内,使得材料强度高达(1.44 ± 0.10) GPa,刚度(61.47 ± 1.0) GPa。通过力学性能测试与断口分析,解释了应力承载以及显微组织的强化机理。这种通过固相反应、微结构设计实现双相合金软-硬、正-负补偿从而得到高强零热膨胀合金的方法,为提高零热膨胀合金综合性能提供了有效的设计思路。

Fe-Pt合金经典的有序、无序结构以及磁体积效应被广泛关注,由磁体积效应造成的反常热膨胀性能也使其成为解释Invar机理的典型材料[49,95]。Li等[96]解析了Fe3Pt块体合金中具有化学有序/无序的纳米畴的交错分布,这种纳米结构畴对Fe-Pt合金热膨胀性能起到重要的调节作用。Cui等[45]结合Fe-Pt相图,在Fe3Pt基体中通过引入适量B原子插入到晶胞体心位置,引起了晶体结构畸变,从而促进原子迁移,加速无序相(A1)向有序相(L12)转变。通过A1和L12纳米畴之间的共晶界面相干耦合来实现热膨胀的调节,最终在多温区得到了具有优异性能的零热膨胀材料:Fe2.85Mn0.15PtB0.25 (αl = 3.12 × 10-7 K-1,273~473 K)、Fe2.75Co0.25PtB0.25 (αl = 9.5 × 10-7 K-1,360~560 K)、Fe2.75Ni0.25PtB0.25 (αl = 1.4 × 10-6 K-1,443~583 K),如图11f[45]所示。

(Hf1 - x Ta x)Fe2是典型的负热膨胀体系,在x = 0.05~1.0范围内,均保持为MgZn2型六方结构[97]。在x = 0.175时,表现出巨大的体积负热膨胀(ΔV / V = 0.80%),其负膨胀效应来源于铁磁-反铁磁一级磁相变[98]。Cen等[46]发现,铸态(Hf, Ta)Fe2存在富Fe晶界,而经过1273 K退火7 d后,富Fe晶界会消失。由此,通过调控Fe含量,使得析出的富Fe相的正热膨胀与(Hf, Ta)Fe2的负膨胀相互抵消,设计出了室温零热膨胀材料Hf0.8Ta0.2Fe2.5 (αl= 0.352 × 10-6 K-1,265~350 K)。

3 结论和展望

零热膨胀金属功能材料在温度变化比较剧烈的极端环境中依然能够保持原有的尺寸不变,可以避免热胀冷缩产生的形变以及热膨胀系数不匹配形成的内应力,这一独特性能能够有效解决生产和生活中遇到的诸多热膨胀问题。随着科技的进步,人们对太空、海洋和地下资源的探索越来越深入,与此同时需要在极端环境下工作的设备数量不断增加,这使得对材料热膨胀性能调控的要求也随之提升,热膨胀性能调控在市场上具有巨大的应用潜力。目前应用最广的零热膨胀金属材料是Invar合金,但是其存在强度低、密度大、易生锈、导热低等缺点,很难满足科技发展需要。金属材料的零热膨胀诱导机制主要是磁体积效应,经过最近20多年来的研究,发现除了磁有序-无序转变能够诱导零热膨胀,局部磁矩改变、变磁转变、短程磁有序、磁结构相变和磁相分离转变都可以产生磁体积效应。至今关于磁体积效应的理解还没有统一的结论,磁体积效应诱发零热膨胀不仅与磁性相关,还应该考虑声子耦合的作用,自旋-声子耦合作用是未来异常热膨胀诱导机制研究的重点。除此之外,基于负热膨胀体系来设计零热膨胀双相合金和复合材料是实现金属基零热膨胀材料广泛应用的有效方法。

零热膨胀金属功能材料在实际应用中除了具备零热膨胀特性之外,往往需要同时兼具其他性能,因此亟需探索更多的多功能零热膨胀金属材料。轻质低热膨胀、高强低热膨胀、高导热低热膨胀和高温低热膨胀是未来热膨胀材料领域研究的重点方向。例如,已报道的零热膨胀材料以金属间化合物为主,但是金属间化合物比较脆,很难进行机械加工,为了提高其力学性能,采用共晶析出第二相的方法进行强化,得到一些力学性能优异的低热膨胀双相合金。随着零热膨胀诱导机制的进一步完善和金属材料制备工艺的进步,零热膨胀金属材料种类将进一步丰富,并且性能会全方面提高,逐渐满足电子、精密探测、能源、航空航天等新材料设计与制造领域对热膨胀调控的需求。

参考文献

Zhao C Z, Wang X, Li Z, et al.

Research progress in the design, manufacturing, characterization, and evaluation of tailorable thermal expansion mechanical metamaterials

[J]. Acta Mater. Compositae Sin., 2024, 41: 4589

[本文引用: 1]

赵淳铮, 王 昕, 李 振 .

可调控热膨胀力学超材料设计制备与表征评测研究进展

[J]. 复合材料学报, 2024, 41: 4589

[本文引用: 1]

Chen J, Hu L, Deng J X, et al.

Negative thermal expansion in functional materials: Controllable thermal expansion by chemical modifications

[J]. Chem. Soc. Rev., 2015, 44: 3522

DOI      PMID      [本文引用: 2]

Negative thermal expansion (NTE) is an intriguing physical property of solids, which is a consequence of a complex interplay among the lattice, phonons, and electrons. Interestingly, a large number of NTE materials have been found in various types of functional materials. In the last two decades good progress has been achieved to discover new phenomena and mechanisms of NTE. In the present review article, NTE is reviewed in functional materials of ferroelectrics, magnetics, multiferroics, superconductors, temperature-induced electron configuration change and so on. Zero thermal expansion (ZTE) of functional materials is emphasized due to the importance for practical applications. The NTE functional materials present a general physical picture to reveal a strong coupling role between physical properties and NTE. There is a general nature of NTE for both ferroelectrics and magnetics, in which NTE is determined by either ferroelectric order or magnetic one. In NTE functional materials, a multi-way to control thermal expansion can be established through the coupling roles of ferroelectricity-NTE, magnetism-NTE, change of electron configuration-NTE, open-framework-NTE, and so on. Chemical modification has been proved to be an effective method to control thermal expansion. Finally, challenges and questions are discussed for the development of NTE materials. There remains a challenge to discover a "perfect" NTE material for each specific application for chemists. The future studies on NTE functional materials will definitely promote the development of NTE materials.

Mohn P.

A century of zero expansion

[J]. Nature, 1999, 400: 18

[本文引用: 1]

Sleight A.

Zero-expansion plan

[J]. Nature, 2003, 425: 674

[本文引用: 1]

Guillaume C E.

Recherches sur les aciers au nickel. Dilatations aux températures élevées; résistance électrique

[J]. Compt. Rend, 1897, 125: 235

[本文引用: 4]

Mary T A, Evans J S O, Vogt T, et al.

Negative thermal expansion from 0.3 to 1050 Kelvin in ZrW2O8

[J]. Science, 1996, 272: 90

[本文引用: 1]

Song Y Z, Shi N K, Deng S Q, et al.

Negative thermal expansion in magnetic materials

[J]. Prog. Mater. Sci., 2021, 121: 100835

[本文引用: 4]

Wang C, Sun Y, Wang L, et al.

Progress on abnormal thermal expansion materials

[J]. Mater. China, 2015, 34: 497

[本文引用: 1]

王 聪, 孙 莹, 王 蕾 .

反常热膨胀功能材料的研究进展

[J]. 中国材料进展, 2015, 34: 497

[本文引用: 1]

van Schilfgaarde M, Abrikosov I A, Johansson B.

Origin of the Invar effect in iron-nickel alloys

[J]. Nature, 1999, 400: 46

[本文引用: 7]

Zhao Y Y, Hu F X, Bao L F, et al.

Giant negative thermal expansion in bonded MnCoGe-based compounds with Ni2In-type hexagonal structure

[J]. J. Am. Chem. Soc., 2015, 137: 1746

[本文引用: 2]

Shen F R, Zhou H B, Hu FX, et al.

Cone-spiral magnetic ordering dominated lattice distortion and giant negative thermal expansion in Fe-doped MnNiGe compounds

[J]. Mater. Horizons, 2020, 7: 804

[本文引用: 2]

Azuma M, Chen W T, Seki H, et al.

Colossal negative thermal expansion in BiNiO3 induced by intermetallic charge transfer

[J]. Nat. Commun., 2011, 2: 347

[本文引用: 1]

Long Y W, Hayashi N, Saito T, et al.

Temperature-induced A-B intersite charge transfer in an A-site-ordered LaCu3Fe4O12 perovskite

[J]. Nature, 2009, 458: 60

[本文引用: 1]

Yu C Y, Lin K, Zhang Q H, et al.

An isotropic zero thermal expansion alloy with super-high toughness

[J]. Nat. Commun., 2024, 15: 2252

DOI      PMID      [本文引用: 11]

Zero thermal expansion (ZTE) alloys with high mechanical response are crucial for their practical usage. Yet, unifying the ZTE behavior and mechanical response in one material is a grand obstacle, especially in multicomponent ZTE alloys. Herein, we report a near isotropic zero thermal expansion (α = 1.10 × 10K, 260-310 K) in the natural heterogeneous LaFeCoSi alloy, which exhibits a super-high toughness of 277.8 ± 14.7 J cm. Chemical partition, in the dual-phase structure, assumes the role of not only modulating thermal expansion through magnetic interaction but also enhancing mechanical properties via interface bonding. The comprehensive analysis reveals that the hierarchically synergistic enhancement among lattice, phase interface, and heterogeneous structure is significant for strong toughness. Our findings pave the way to tailor thermal expansion and obtain prominent mechanical properties in multicomponent alloys, which is essential to ultra-stable functional materials.© 2024. The Author(s).

Yu C Y, Lin K, Jiang S H, et al.

Plastic and low-cost axial zero thermal expansion alloy by a natural dual-phase composite

[J]. Nat. Commun., 2021, 12: 4701

DOI      PMID      [本文引用: 4]

Zero thermal expansion (ZTE) alloys possess unique dimensional stability, high thermal and electrical conductivities. Their practical application under heat and stress is however limited by their inherent brittleness because ZTE and plasticity are generally exclusive in a single-phase material. Besides, the performance of ZTE alloys is highly sensitive to change of compositions, so conventional synthesis methods such as alloying or the design of multiphase to improve its thermal and mechanical properties are usually inapplicable. In this study, by adopting a one-step eutectic reaction method, we overcome this challenge. A natural dual-phase composite with ZTE and plasticity was synthesized by melting 4 atom% holmium with pure iron. The dual-phase alloy shows moderate plasticity and strength, axial zero thermal expansion, and stable thermal cycling performance as well as low cost. By using synchrotron X-ray diffraction, in-situ neutron diffraction and microscopy, the critical mechanism of dual-phase synergy on both thermal expansion regulation and mechanical property enhancement is revealed. These results demonstrate that eutectic reaction is likely to be a universal and effective method for the design of high-performance intermetallic-compound-based ZTE alloys.© 2021. The Author(s).

Yu C Y, Lin K, Chen X, et al.

Superior zero thermal expansion dual-phase alloy via boron-migration mediated solid-state reaction

[J]. Nat. Commun., 2023, 14: 3135

DOI      PMID      [本文引用: 7]

Rapid progress in modern technologies demands zero thermal expansion (ZTE) materials with multi-property profiles to withstand harsh service conditions. Thus far, the majority of documented ZTE materials have shortcomings in different aspects that limit their practical utilization. Here, we report on a superior isotropic ZTE alloy with collective properties regarding wide operating temperature windows, high strength-stiffness, and cyclic thermal stability. A boron-migration-mediated solid-state reaction (BMSR) constructs a salient "plum pudding" structure in a dual-phase Er-Fe-B alloy, where the precursor ErFe phase reacts with the migrated boron and transforms into the target ErFeB (pudding) and α-Fe phases (plum). The formation of such microstructure helps to eliminate apparent crystallographic texture, tailor and form isotropic ZTE, and simultaneously enhance the strength and toughness of the alloy. These findings suggest a promising design paradigm for comprehensive performance ZTE alloys.© 2023. The Author(s).

Guillaume C É.

Recherches sur les aciers au nickel

[J]. J. Phys. Theor. Appl., 1898, 7: 262

[本文引用: 1]

Song Y Z, Sun Q, Yokoyama T, et al.

Transforming thermal expansion from positive to negative: The case of cubic magnetic compounds of (Zr, Nb)Fe2

[J]. J. Phys. Chem. Lett., 2020, 11: 1954

[本文引用: 8]

Sun Y M, Cao Y L, Hu S X, et al.

Interplanar ferromagnetism enhanced ultrawide zero thermal expansion in kagome cubic intermetallic (Zr, Nb)Fe2

[J]. J. Am. Chem. Soc., 2023, 145: 17096

[本文引用: 6]

Li W J, Lin K, Yan Y, et al.

A seawater‐corrosion‐resistant and isotropic zero thermal expansion (Zr, Ta)(Fe, Co)2 alloy

[J]. Adv. Mater., 2022, 34: 2109592

[本文引用: 2]

Cao Y L, Xu Y, Khmelevskyi S, et al.

Interplanar magnetic orders and symmetry-tuned zero thermal expansion in kagomé metal (Zr,Ta)Fe2

[J]. Chem. Mater., 2023, 35: 9167

[本文引用: 6]

Song Y Z, Sun Q, Xu M, et al.

Negative thermal expansion in (Sc,Ti)Fe2 induced by an unconventional magnetovolume effect

[J]. Mater. Horizons, 2020, 7: 275

[本文引用: 7]

Jing-Ting Z, Yibole H, Narsu B, et al.

Structural and magnetic properties of Sc1 - x Nb x Fe2 intermetallics showing anomalous zero thermal expansion

[J]. Intermetallics, 2021, 136: 107252

[本文引用: 2]

Xu M, Song Y Z, Xu Y J, et al.

High-temperature zero thermal expansion in HfFe2 + δ from added ferromagnetic paths

[J]. Chem. Mater., 2022, 34: 9437

[本文引用: 6]

Dong X Y, Lin K, Yu C Y, et al.

Zero thermal expansion in non-stoichiometric and single-phase (Hf, Nb) Fe2.5 alloy

[J]. Scr. Mater., 2023, 229: 115388

[本文引用: 2]

Lin K, Zhang W B, Yu C Y, et al.

Chemical heterogeneity modulated zero thermal expansion alloy over super-wide temperature range

[J]. Cell Rep. Phys. Sci., 2023, 4: 101254

[本文引用: 6]

Xu J W, Wang Z, Huang H, et al.

Significant zero thermal expansion via enhanced magnetoelastic coupling in kagome magnets

[J]. Adv. Mater., 2023, 35: 2208635

[本文引用: 2]

Song Y Z, Chen J, Liu X Z, et al.

Zero thermal expansion in magnetic and metallic Tb(Co,Fe)2 intermetallic compounds

[J]. J. Am. Chem. Soc., 2018, 140: 602

[本文引用: 8]

Hu J Y, Lin K, Cao Y L, et al.

Adjustable magnetic phase transition inducing unusual zero thermal expansion in cubic RCo2-based intermetallic compounds (R = rare earth)

[J]. Inorg. Chem., 2019, 58: 5401

[本文引用: 8]

Hao J Z, Shen F R, Hu F X, et al.

Realization of ultra-low thermal expansion over a broad temperature interval in Gd x (Dy0.5Ho0.5)1 - x -Co2 compounds

[J]. Scr. Mater., 2020, 185: 181

[本文引用: 2]

Li S P, Huang R J, Zhao Y Q, et al.

Zero thermal expansion achieved by an electrolytic hydriding method in La(Fe,Si)13 compounds

[J]. Adv. Funct. Mater., 2017, 27: 1604195

[本文引用: 9]

Li W, Huang R J, Wang W, et al.

Abnormal thermal expansion properties of cubic NaZn13-type La(Fe, Al)13 compounds

[J]. Phys. Chem. Chem. Phys., 2015, 17: 5556

[本文引用: 6]

Wang W, Huang R J, Li W, et al.

Zero thermal expansion in NaZn13-type La(Fe,Si)13 compounds

[J]. Phys. Chem. Chem. Phys., 2015, 17: 2352

DOI      PMID      [本文引用: 2]

A zero thermal expansion material in a pure form of NaZn13-type La(Fe,Si)13 was fabricated. Through optimizing the chemical composition, an isotropic zero thermal expansion material is achieved. The obtained materials exhibit a low expansion of |α| < 1.0 × 10(-6) K(-1) (α is the coefficient of linear thermal expansion) over a broad temperature range (15-150 K). The present study indicates that the thermal expansion behavior of the NaZn13-type La(Fe,Si)13 compounds depends mainly on the content of Si element. This new material is desirable in many fields of industry as a reliable and low-cost zero thermal expansion material.

Cao Y L, Lin K, Khmelevskyi S, et al.

Ultrawide temperature range super-Invar behavior of R2(Fe,Co)17 materials (R = rare earth)

[J]. Phys. Rev. Lett., 2021, 127: 055501

[本文引用: 6]

Dan S, Mukherjee S, Mazumdar C, et al.

Zero thermal expansion with high Curie temperature in Ho2Fe16Cr alloy

[J]. RSC Adv., 2016, 6: 94809

[本文引用: 3]

Qiao Y Q, Song Y Z, Xu M, et al.

Controllable thermal expansion and magnetic structure in Er2(Fe, Co)14B intermetallic compounds

[J]. Inorg. Chem. Front., 2019, 6: 3225

[本文引用: 2]

Shen F R, Kuang H, Hu F X, et al.

Ultra-low thermal expansion realized in giant negative thermal expansion materials through self-compensation

[J]. APL Mater., 2017, 5: 106102

[本文引用: 2]

Li W J, Lin K, Cao Y L, et al.

Strong coupling of magnetism and lattice induces near-zero thermal expansion over broad temperature windows in ErFe10V2 - x Mo x Compounds

[J]. CCS Chem., 2021, 3: 1009

[本文引用: 2]

Yu C Y, Lin K, Cao Y L, et al.

Two-dimensional zero thermal expansion in low-cost Mn x Fe5 - x Si3 alloys via integrating crystallographic texture and magneto-volume effect

[J]. Sci. China Mater., 2022, 65: 1912

[本文引用: 2]

Ahadi A, Matsushita Y, Sawaguchi T, et al.

Origin of zero and negative thermal expansion in severely-deformed superelastic NiTi alloy

[J]. Acta Mater., 2017, 124: 79

[本文引用: 6]

Li Q, Deng Z Z, Onuki Y, et al.

In-plane low thermal expansion of NiTi via controlled cross rolling

[J]. Acta Mater., 2021, 204: 116506

[本文引用: 4]

Wang H L, Lai D K Z, Xu J P, et al.

Nano-precipitation leading to linear zero thermal expansion over a wide temperature range in Ti22Nb

[J]. Scr. Mater., 2021, 205: 114222

[本文引用: 6]

Pang X L, Song Y Z, Shi N K, et al.

Design of zero thermal expansion and high thermal conductivity in machinable xLFCS/Cu metal matrix composites

[J]. Composites, 2022, 238B: 109883

[本文引用: 4]

Liu J, Gong Y Y, Wang J W, et al.

Realization of zero thermal expansion in La(Fe, Si)13-based system with high mechanical stability

[J]. Mater. Des., 2018, 148: 71

[本文引用: 3]

Cui J, Sun Y, Shi K W, et al.

Invar effect in the wide and higher temperature range by coherent coupling in Fe-based alloy

[J]. Adv. Funct. Mater., 2024, 34: 2309431

[本文引用: 6]

Cen D Y, Wang B, Chu R X, et al.

Design of (Hf,Ta)Fe2/Fe composite with zero thermal expansion covering room temperature

[J]. Scr. Mater., 2020, 186: 331

[本文引用: 5]

Weiss R J.

The origin of the ‘Invar’ effect

[J]. Proc. Phys. Soc., 1963, 82: 281

[本文引用: 1]

Lohaus S H, Heine M, Guzman P, et al.

A thermodynamic explanation of the Invar effect

[J]. Nat. Phys., 2023, 19: 1642

[本文引用: 8]

Khmelevskyi S, Turek I, Mohn P.

Large negative magnetic contribution to the thermal expansion in iron-platinum alloys: Quantitative theory of the Invar effect

[J]. Phys. Rev. Lett., 2003, 91: 037201

[本文引用: 2]

Matsui M, Shimizu T, Yamada H, et al.

Magnetic properties and thermal expansion of Fe-Pd Invar alloys

[J]. J. Magn. Magn. Mater., 1980, 15-18: 1201

[本文引用: 1]

Rode V E, Finkelberg S A, Lyalin A I, et al.

Invar anomalies of Fe-Cr alloys

[J]. J. Magn. Magn. Mater., 1983, 31-34: 293

[本文引用: 1]

Nishihara Y, Yamaguchi Y.

Magnetic properties of the (Sc1 - x Ti x)-Fe2 system having two magnetic states with different degrees of localization

[J]. J. Phys. Soc. Jpn., 1986, 55: 920

[本文引用: 1]

Li L F, Tong P, Zou Y M, et al.

Good comprehensive performance of Laves phase Hf1 - x Ta x Fe2 as negative thermal expansion materials

[J]. Acta Mater., 2018, 161: 258

[本文引用: 1]

Qiao Y Q, Song Y Z, Lin K, et al.

Negative thermal expansion in (Hf, Ti)Fe2 induced by the ferromagnetic and antiferromagnetic phase coexistence

[J]. Inorg. Chem., 2019, 58: 5380

[本文引用: 1]

Song Y Z, Chen J, Liu X Z, et al.

Structure, magnetism, and tunable negative thermal expansion in (Hf,Nb)Fe2 alloys

[J]. Chem. Mater., 2017, 29: 7078

[本文引用: 1]

Shiga M, Nakamura Y.

Magnetovolume effects and Invar characters of (Zr1 - x Nb x)Fe2

[J]. J. Phys. Soc. Jpn., 1979, 47: 1446

[本文引用: 1]

Muraoka Y, Okuda H, Shiga M, et al.

Magnetovolume effects in Gd x Y1 - x Co2

[J]. J. Phys. Soc. Jpn., 1984, 53: 331

[本文引用: 1]

Gratz E, Markosyan A S.

Physical properties of RCo2 Laves phases

[J]. J. Phys., 2001, 13: R385

[本文引用: 1]

von Ranke P J, de Oliveira N A.

On the nature of the magnetic phase transition of the HoCo2 intermetallic

[J]. J. Appl. Phys., 1998, 83: 6967

[本文引用: 1]

Morrison K, Dupas A, Mudryk Y, et al.

Identifying the critical point of the weakly first-order itinerant magnet DyCo2 with complementary magnetization and calorimetric measurements

[J]. Phys. Rev., 2013, 87B: 134421

[本文引用: 1]

Lizárraga R.

Structural and magnetic properties of the Gd-based bulk metallic glasses GdFe2, GdCo2, and GdNi2 from first principles

[J]. Phys. Rev., 2016, 94B: 174201

[本文引用: 1]

Huang R J, Liu Y Y, Fan W, et al.

Giant negative thermal expansion in NaZn13-type La(Fe, Si, Co)13 compounds

[J]. J. Am. Chem. Soc., 2013, 135: 11469

[本文引用: 1]

Song Y Z, Huang R J, Liu Y, et al.

Magnetic-field-induced strong negative thermal expansion in La(Fe, Al)13

[J]. Chem. Mater., 2020, 32: 7535

Shen B G, Hu F X, Dong Q Y, et al.

Magnetic properties and magnetocaloric effects in NaZn13-type La(Fe, Al)13-based compounds

[J]. Chin. Phys., 2013, 22B: 017502

Long F X, Song Y Z, Chen J.

La(Fe, Si/Al)13-based materials with exceptional magnetic functionalities: A review

[J]. Microstructures, 2024, 4: 2024011

[本文引用: 1]

Cao Y L, Zhou H W, Khmelevskyi S, et al.

Pressure-modulated magnetism and negative thermal expansion in the Ho2Fe17 intermetallic compound

[J]. Chem. Mater., 2023, 35: 3249

[本文引用: 1]

Givord D, Lemaire R.

Magnetic transition and anomalous thermal expansion in R2Fe17 compounds

[J]. IEEE Trans. Magn., 1974, 10: 109

Cao Y L, Lin K, Liu Z N, et al.

Zero thermal expansion and its mechanism of Ho2Fe11Al6 intermetallic compounds at low temperature

[J]. J. Chin. Soc. Rare Earths, 2020, 38: 440

[本文引用: 1]

曹宜力, 林 鲲, 刘占宁 .

Ho2Fe11Al6金属间化合物的低温零热膨胀及其机制

[J]. 中国稀土学报, 2020, 38: 440

[本文引用: 1]

Buschow K H J, Grössinger R.

Spontaneous volume magnetostriction in R2Fe14B compounds

[J]. J. Less Common Met., 1987, 135: 39

[本文引用: 1]

Cheng B P, Yang Y C, Fu S C, et al.

Thermal expansion anomalies of R2(Fe1 - x M x)14B

[J]. J. Appl. Phys., 1987, 61: 3586

Loewenhaupt M, Prager M, Murani A P, et al.

Inelastic neutron scattering on RE2Fe14B (RE = Y, Ce, Nd, Dy and Er)

[J]. J. Magn. Magn. Mater., 1988, 76: 408

[本文引用: 1]

Yang S, Ma S C, Liu K, et al.

Controllable negative thermal expansion by mechanical pulverizing in hexagonal Mn0.965Co1.035Ge compounds

[J]. Inorg. Chem., 2018, 57: 14199

[本文引用: 2]

Ren Q Y, Hutchison W, Wang J L, et al.

Negative thermal expansion of Ni-doped MnCoGe at room-temperature magnetic tuning

[J]. ACS Appl. Mater. Interfaces, 2019, 11: 17531

[本文引用: 1]

Liu Y, Qiao K M, Zuo S L, et al.

Negative thermal expansion and magnetocaloric effect in Mn-Co-Ge-In thin films

[J]. Appl. Phys. Lett., 2018, 112: 012401

[本文引用: 1]

Liu E K, Wang W H, Feng L, et al.

Stable magnetostructural coupling with tunable magnetoresponsive effects in hexagonal ferromagnets

[J]. Nat. Commun., 2012, 3: 873

DOI      PMID      [本文引用: 1]

The magnetostructural coupling between the structural and the magnetic transition has a crucial role in magnetoresponsive effects in a martensitic-transition system. A combination of various magnetoresponsive effects based on this coupling may facilitate the multifunctional applications of a host material. Here we demonstrate the feasibility of obtaining a stable magnetostructural coupling over a broad temperature window from 350 to 70 K, in combination with tunable magnetoresponsive effects, in MnNiGe:Fe alloys. The alloy exhibits a magnetic-field-induced martensitic transition from paramagnetic austenite to ferromagnetic martensite. The results indicate that stable magnetostructural coupling is accessible in hexagonal phase-transition systems to attain the magnetoresponsive effects with broad tunability.

Caron L, Trung N T, Brück E, et al.

Pressure-tuned magnetocaloric effect in Mn0.93Cr0.07CoGe

[J]. Phys. Rev., 2011, 84B: 020414

Wu R R, Bao L F, Hu F X, et al.

Giant barocaloric effect in hexagonal Ni2In-type Mn-Co-Ge-In compounds around room temperature

[J]. Sci. Rep., 2015, 5: 18027

[本文引用: 1]

Sun X M, Cong D Y, Ren Y, et al.

Giant negative thermal expansion in Fe-Mn-Ga magnetic shape memory alloys

[J]. Appl. Phys. Lett., 2018, 113: 041903

[本文引用: 1]

Coates C S, Goodwin A L.

How to quantify isotropic negative thermal expansion: Magnitude, range, or both?

[J]. Mater. Horizons, 2019, 6: 211

[本文引用: 1]

Xu J H, Liu X M, Xia Y H, et al.

Magnetic properties and magnetocaloric effect of (Mn1 - x Fe x)5Sn3 (x = 0-0.5) compounds

[J]. J. Appl. Phys., 2013, 113: 17A921

[本文引用: 1]

Sürgers C, Kittler W, Wolf T, et al.

Anomalous Hall effect in the noncollinear antiferromagnet Mn5Si3

[J]. AIP Adv., 2016, 6: 055604

[本文引用: 1]

Kainuma R, Wang J J, Omori T, et al.

Invar-type effect induced by cold-rolling deformation in shape memory alloys

[J]. Appl. Phys. Lett., 2002, 80: 4348

[本文引用: 1]

Nakai M, Niinomi M, Akahori T, et al.

Anomalous thermal expansion of cold-rolled Ti-Nb-Ta-Zr alloy

[J]. Mater. Trans., 2009, 50: 423

[本文引用: 1]

Saito T, Furuta T, Hwang J H, et al.

Multifunctional alloys obtained via a dislocation-free plastic deformation mechanism

[J]. Science, 2003, 300: 464

PMID     

We describe a group of alloys that exhibit "super" properties, such as ultralow elastic modulus, ultrahigh strength, super elasticity, and super plasticity, at room temperature and that show Elinvar and Invar behavior. These "super" properties are attributable to a dislocation-free plastic deformation mechanism. In cold-worked alloys, this mechanism forms elastic strain fields of hierarchical structure that range in size from the nanometer scale to several tens of micrometers. The resultant elastic strain energy leads to a number of enhanced material properties.

Kim H Y, Wei L S, Kobayashi S, et al.

Nanodomain structure and its effect on abnormal thermal expansion behavior of a Ti-23Nb-2Zr-0.7Ta-1.2O alloy

[J]. Acta Mater., 2013, 61: 4874

[本文引用: 1]

Wei L S, Kim H Y, Miyazaki S.

Effects of oxygen concentration and phase stability on nano-domain structure and thermal expansion behavior of Ti-Nb-Zr-Ta-O alloys

[J]. Acta Mater., 2015, 100: 313

[本文引用: 1]

Monroe J A, Gehring D, Karaman I, et al.

Tailored thermal expansion alloys

[J]. Acta Mater., 2016, 102: 333

[本文引用: 1]

Bönisch M, Panigrahi A, Stoica M, et al.

Giant thermal expansion and α-precipitation pathways in Ti-alloys

[J]. Nat. Commun., 2017, 8: 1429

[本文引用: 2]

Demakov S, Semkina I, Stepanov S I.

Abnormal behavior of lattice spacing of titanium orthorhombic martensite

[J]. Mater. Sci. Forum, 2017, 907: 14

[本文引用: 1]

Rao Z Y, Tung P Y, Xie R W, et al.

Machine learning-enabled high-entropy alloy discovery

[J]. Science, 2022, 378: 78

DOI      PMID      [本文引用: 1]

High-entropy alloys are solid solutions of multiple principal elements that are capable of reaching composition and property regimes inaccessible for dilute materials. Discovering those with valuable properties, however, too often relies on serendipity, because thermodynamic alloy design rules alone often fail in high-dimensional composition spaces. We propose an active learning strategy to accelerate the design of high-entropy Invar alloys in a practically infinite compositional space based on very sparse data. Our approach works as a closed-loop, integrating machine learning with density-functional theory, thermodynamic calculations, and experiments. After processing and characterizing 17 new alloys out of millions of possible compositions, we identified two high-entropy Invar alloys with extremely low thermal expansion coefficients around 2 × 10 per degree kelvin at 300 kelvin. We believe this to be a suitable pathway for the fast and automated discovery of high-entropy alloys with optimal thermal, magnetic, and electrical properties.

Zhao Y Q, Huang R J, Shan Y, et al.

Low-temperature abnormal thermal expansion property of Mn doped cubic NaZn13-type La(Fe, Al)13 compounds

[J]. J. Phys., 2017, 897: 012005

[本文引用: 1]

Sun B H, Lu W J, Gault B, et al.

Chemical heterogeneity enhances hydrogen resistance in high-strength steels

[J]. Nat. Mater., 2021, 20: 1629

DOI      PMID      [本文引用: 1]

The antagonism between strength and resistance to hydrogen embrittlement in metallic materials is an intrinsic obstacle to the design of lightweight yet reliable structural components operated in hydrogen-containing environments. Economical and scalable microstructural solutions to this challenge must be found. Here, we introduce a counterintuitive strategy to exploit the typically undesired chemical heterogeneity within the material's microstructure that enables local enhancement of crack resistance and local hydrogen trapping. We use this approach in a manganese-containing high-strength steel and produce a high dispersion of manganese-rich zones within the microstructure. These solute-rich buffer regions allow for local micro-tuning of the phase stability, arresting hydrogen-induced microcracks and thus interrupting the percolation of hydrogen-assisted damage. This results in a superior hydrogen embrittlement resistance (better by a factor of two) without sacrificing the material's strength and ductility. The strategy of exploiting chemical heterogeneities, rather than avoiding them, broadens the horizon for microstructure engineering via advanced thermomechanical processing.

Ding R, Yao Y J, Sun B H, et al.

Chemical boundary engineering: A new route toward lean, ultrastrong yet ductile steels

[J]. Sci. Adv., 2020, 6: eaay1430

[本文引用: 1]

Liu Y, Li J, Qian Y, et al.

Isotropic negative thermal expansion in the multiple-phase La-Fe-Co-Si-Cu alloys with enhanced strength and ductility

[J]. Acta Mater., 2024, 275: 120058

[本文引用: 4]

Kakeshita T, Takeuchi T, Fukuda T, et al.

Giant magnetostriction in an ordered Fe3Pt single crystal exhibiting a martensitic transformation

[J]. Appl. Phys. Lett., 2000, 77: 1502

[本文引用: 1]

Li Q, Ren Y, Zhang Q H, et al.

Chemical order-disorder nanodomains in Fe3Pt bulk alloy

[J]. Natl. Sci. Rev., 2022, 9: nwac053

[本文引用: 1]

Rechenberg H R, Morellon L, Algarabel P A, et al.

Magnetic moment at highly frustrated sites of antiferromagnetic Laves phase structures

[J]. Phys. Rev., 2005, 71B: 104412

[本文引用: 1]

Diop L V B, Isnard O, Suard E, et al.

Neutron diffraction study of the itinerant-electron metamagnetic Hf0.825Ta0.175Fe2 compound

[J]. Solid State Commun., 2016, 229: 16

[本文引用: 1]

/