负焓合金化设计获得高强韧材料

负焓合金化设计获得高强韧材料

安子冰，王钊为，刘珊珊，薛现猛，孙  铭，何亚鹏，刘银昭，毛圣成，张  泽，韩晓东^*

(1．南方科技大学 工学院，材料科学与工程系，广东 深圳 518000；2. 北京工业大学 固体微结构与性能北京市重点实验室，材料科学与工程学院，北京 100124；3．浙江大学 电子显微镜中心，硅及先进半导体材料全国重点实验室，材料科学与工程学院，浙江 杭州 310027)

摘  要  高熵合金是近年来发展的一种新型合金体系，具有较大的晶格畸变特征，展示出了高强度、高硬度、高耐磨性等力学特性。高熵合金通常呈现出高熵驱动的理想随机固溶体结构。因此，类似于传统金属及合金材料，缺乏调控位错等塑性变形载体的能力，高熵合金的强度与韧性之间依旧存在倒置矛盾关系。根据Gibbs自由能理论，混合焓是调控材料显微结构与力学性能的另一个抓手，其完全独立于混合熵并且与其相互竞争。然而，利用混合焓调控材料微观结构及力学性能在国际领域基本属于空白。课题组通过对系列高熵合金研究结果的梳理与总结，并结合对材料热力学与电子显微学的认识，阐明了混合焓对材料显微结构与力学性能的影响机制。本文综述了课题组针对材料混合焓−微观结构−力学性能相关性的研究工作，揭示了负混合焓是局部化学有序及成分波动等异质结构形成的本质原因，阐明了负焓合金的强韧化机理，探索了负焓强韧化合金设计路线，建立了混合焓、显微结构与力学性能的内在联系。负焓合金化设计理念不仅为高强韧合金设计提供了范例、更有助于发展先进结构材料新体系，同时也为传统材料的合金化设计提供数据支撑和理论支持。

关键词   高熵合金；显微结构；力学性能；混合焓；负焓合金

中图分类号：TG115.21⁺5.3；O76；TG146；O482；TB34  文献标识码：A         doi:10.3969/j.issn.1000-6281.2024.05.010

Negative enthalpy alloy design strategy towards strong yet ductile materials

AN Zibing^1，2, WANG Zhaowei¹, LIU Shanshan¹, XUE Xianmeng², SUN Ming², HE Yapeng², MAO Shengcheng², ZHANG Ze³, HAN Xiaodong^1，2*

(1. Southern University of Science and Technology, Department of Materials Science and Engineering, Shenzhen Guangdong 518055; 2. Being Key Laboratory of Microstructure and Advanced Materials, College of materials science and engineering, Beijing University of Technology, Beijing 100124; 3. Center of Electron Microscopy, State Key Laboratory of Silicon and Advanced Semiconductor Materials, School of Material Science and Engineering, Zhejiang University, Hangzhou Zhejiang 310027, China)

Abstract     High-entropy alloys (HEAs) are a novel class of alloy systems developed in recent years, characterized by significant lattice distortion and superior mechanical properties, such as high strength, hardness, and wear resistance. HEAs typically adopt an ideal random solid solution structure driven by high entropy. However, much like traditional metals and alloys, they lack effective control over plastic deformation carriers, such as dislocations, leading to the classic strength−ductility trade-off. According to Gibbs free energy theory, mixing enthalpy is another crucial factor that influences the microstructure and mechanical properties of materials, operating independently from mixing entropy and often in competition with mixing entropy. Despite its importance, the role of mixing enthalpy in controlling microstructure and mechanical properties has largely remained unexplored in global research. By reviewing and summarizing our findings on various HEAs, and integrating insights from material thermodynamics and electron microscopy, we have clarified the mechanism by which mixing enthalpy affects the microstructure and mechanical properties of materials. This paper summarizes our research on the correlation between mixing enthalpy, microstructure and mechanical properties, revealing that negative mixing enthalpy is a key factor in the formation of heterogeneous structures such as local chemical ordering and composition fluctuations. We explain the strengthening and toughening mechanisms in alloys with negative enthalpy, explore design strategies based on negative mixing enthalpy, and establish the intrinsic relationship between mixing enthalpy, microstructure and mechanical properties. The concept of designing negative enthalpy alloys not only provides a promising pathway for developing strong yet ductile alloys, but also contributes to the advancement of next-generation structural materials. Furthermore, it offers valuable data and theoretical insights to support alloy design in traditional materials.

Keywords     high-entropy alloy; microstructure; mechanical property; mixing enthalpy; negative enthalpy alloy

“全文下载请到同方知网，万方数据库或重庆维普等数据库中下载！”

[1]  MA E J J. Eight routes to improve the tensile ductility of bulk nanostructured metals and alloys [J]. JOM, 2006, 58: 49-53.

[2]  LU K，LU L，SURESH S. Strengthening materials by engineering coherent internal boundaries at the nanoscale [J]. Science, 2009, 324(5925): 349-352.

[3]  LI H，ZONG H，LI S，et al. Uniting tensile ductility with ultrahigh strength via composition undulation [J]. Nature, 2022, 604(7905): 273-279.

[4]  CHENG Z，ZHOU H，LU Q，et al. Extra strengthening and work hardening in gradient nanotwinned metals [J]. Science, 2018, 362(6414): eaau1925.

[5]  WANG Y，CHEN M，ZHOU F，et al. High tensile ductility in a nanostructured metal [J]. Nature, 2002, 419(6910): 912-915.

[6]  WU X，JIANG P，CHEN L，et al. Extraordinary strain hardening by gradient structure[M]. Heterostructured Materials: Jenny Stanford Publishing, 2021: 53-71.

[7]  ZHU Y，WU X. Heterostructured materials [J]. Progress in Materials Science, 2023, 131: 101019.

[8]  YEH J W，CHEN S K，LIN S J，et al. Nanostructured high-entropy alloys with multiple principal elements: Novel alloy design concepts and outcomes [J]. Advanced Engineering Materials, 2004, 6(5): 299-303.

[9]  ZHANG L S，MA G L，FU L C，et al. Recent progress in high-entropy alloys [J]. Advanced Materials Research, 2013, 631-632: 227-232.

[10]  SOHRABI M J，KALHOR A，MIRZADEH H，et al. Tailoring the strengthening mechanisms of high-entropy alloys toward excellent strength-ductility synergy by metalloid silicon alloying: A review [J]. Progress in Materials Science, 2024, 144: 101295.

[11]  GEORGE E P，RITCHIE R O. High-entropy materials [J]. MRS Bulletin, 2022, 47(2): 145-150.

[12]  LI J，CHEN Y，HE Q，et al. Heterogeneous lattice strain strengthening in severely distorted crystalline solids [J]. Proceedings of the National Academy of Sciences, 2022, 119(25): e2200607119.

[13]  SOHN S S，KWIATKOWSKI DA SILVA A，IKEDA Y，et al. Ultrastrong medium-entropy single-phase alloys designed via severe lattice distortion [J]. Advanced Materials, 2019, 31(8): 1807142.

[14]  LEI Z，LIU X，WU Y，et al. Enhanced strength and ductility in a high-entropy alloy via ordered oxygen complexes [J]. Nature, 2018, 563(7732): 546-550.

[15]  DING Q，ZHANG Y，CHEN X，et al. Tuning element distribution, structure and properties by composition in high-entropy alloys [J]. Nature, 2019, 574(7777): 223-227.

[16]  AN Z，MAO S，LIU Y，et al. A novel HfNbTaTiV high-entropy alloy of superior mechanical properties designed on the principle of maximum lattice distortion [J]. Journal of Materials Science & Technology, 2021, 79: 109-117.

[17]  FENG R，FENG B，GAO M C，et al. Superior high-temperature strength in a supersaturated refractory high-entropy alloy [J]. Advanced Materials, 2021, 33(48): 2102401.

[18]  LEE C，SONG G，GAO M C，et al. Lattice distortion in a strong and ductile refractory high-entropy alloy [J]. Acta Materialia, 2018, 160: 158-172.

[19]  AN Z，MAO S，LIU Y，et al. Hierarchical grain size and nanotwin gradient microstructure for improved mechanical properties of a non-equiatomic CoCrFeMnNi high-entropy alloy [J]. Journal of Materials Science & Technology, 2021, 92: 195-207.

[20]  LEE C，CHOU Y，KIM G，et al. Lattice-distortion-enhanced yield strength in a refractory high-entropy alloy [J]. Advanced Materials, 2020, 32(49): 2004029.

[21]  LIU W H，LU Z P，HE J Y，et al. Ductile CoCrFeNiMox high entropy alloys strengthened by hard intermetallic phases [J]. Acta Materialia, 2016, 116: 332-342.

[22]  OTTO F，HANOLD N L，GEORGE E P.  Microstructural evolution after thermomechanical processing in an equiatomic, single-phase CoCrFeMnNi high-entropy alloy with special focus on twin boundaries [J]. Intermetallics, 2014, 54: 39-48.

[23]  OTTO F，DLOUHÝ A，SOMSEN C，et al. The influences of temperature and microstructure on the tensile properties of a CoCrFeMnNi high-entropy alloy [J]. Acta Materialia, 2013, 61(15): 5743-5755.

[24]  LI D，LI C，FENG T，et al. High-entropy Al0.3CoCrFeNi alloy fibers with high tensile strength and ductility at ambient and cryogenic temperatures [J]. Acta Materialia, 2017, 123: 285-294.

[25]  BU Y，WU Y，LEI Z，et al. Local chemical fluctuation mediated ductility in body-centered-cubic high-entropy alloys [J]. Materials Today, 2021, 46: 28-34.

[26]  AN Z，LI A，MAO S，et al. Negative mixing enthalpy solid solutions deliver high strength and ductility [J]. Nature, 2024, 625(7996): 697-702.

[27]  CHEN X，WANG Q，CHENG Z，et al. Direct observation of chemical short-range order in a medium-entropy alloy [J]. Nature, 2021, 592(7856): 712-716.

[28]  LIU D，WANG Q，WANG J，et al. Chemical short-range order inFe₅₀Mn₃₀Co₁₀Cr₁₀ high-entropy alloy [J]. Materials Today Nano, 2021, 16: 100139.

[29]  ZHANG R，ZHAO S，DING J，et al. Short-range order and its impact on the CrCoNi medium-entropy alloy [J]. Nature, 2020, 581(7808): 283-287.

[30]  WANG J，JIANG P，YUAN F，et al. Chemical medium-range order in a medium-entropy alloy [J]. Nature Communications, 2022, 13(1): 1021.

[31]  AN Z，MAO S，YANG T，et al. Spinodal-modulated solid solution delivers a strong and ductile refractory high-entropy alloy [J]. Materials Horizons, 2021, 8(3): 948-955.

[32] CHEN Y，FANG Y，WANG R，et al. Achieving high strength and ductility in high-entropy alloys via spinodal decomposition-induced compositional heterogeneity [J]. Journal of Materials Science & Technology, 2023, 141: 149-154.

[33]  SHI P，LI R，LI Y，et al. Hierarchical crack buffering triples ductility in eutectic herringbone high-entropy alloys [J]. Science, 2021, 373(6557): 912-918.

[34]  AN Z，YANG T，SHI C，et al. Negative enthalpy alloys and local chemical ordering: a concept and route leading to synergy of strength and ductility [J]. National Science Review, 2024, 11(4): nwae026.

[35]  ZHANG Y，ZHOU Y J，LIN J P，et al. Solid-solution phase formation rules for multi-component alloys [J]. Advanced Engineering Materials, 2008, 10(6): 534-538.

[36]  GAO M C，ZHANG C，GAO P，et al. Thermodynamics of concentrated solid solution alloys [J]. Current Opinion in Solid State and Materials Science, 2017, 21(5): 238-251.

[37]  MIRACLE D B，SENKOV O N. A critical review of high entropy alloys and related concepts [J]. Acta Materialia, 2017, 122: 448-511.

[38]  ZHANG W，LIAW P K，ZHANG Y. Science and technology in high-entropy alloys [J]. Science China Materials, 2018, 61(1): 2-22.

[39]  TAKEUCHI A，INOUE A. Classification of bulk metallic glasses by atomic size difference, heat of mixing and period of constituent elements and its application to characterization of the main alloying element [J]. Materials Transactions, 2005, 46(12): 2817-2829.

[40]  SENKOV O N，SCOTT J M，SENKOVA S V，et al. Microstructure and room temperature properties of a high-entropy TaNbHfZrTi alloy [J]. Journal of Alloys and Compounds, 2011, 509(20): 6043-6048.

[41]  OTTO F，YANG Y，BEI H，et al. Relative effects of enthalpy and entropy on the phase stability of equiatomic high-entropy alloys [J].  Acta Materialia, 2013, 61(7): 2628-2638.

[42]  TSAI M H，YEH J W. High-entropy alloys: A critical review [J]. Materials Research Letters, 2014, 2(3): 107-123.

[43]  SENKOV O N，SENKOVA S V，MIRACLE D B，et al. Mechanical properties of low-density, refractory multi-principal element alloys of the Cr–Nb–Ti–V–Zr system [J]. Materials Science and Engineering: A, 2013, 565: 51-62.

[44]  XIANG C，ZHANG Z M，FU H M，et al. Microstructure, mechanical properties, and corrosion behavior of MoNbFeCrV, MoNbFeCrTi, and MoNbFeVTi high-entropy alloys [J]. Acta Metallurgica Sinica (English Letters), 2019, 32(9): 1053-1064.

[45]  HSU W L，TSAI C W，YEH A C，et al. Clarifying the four core effects of high-entropy materials [J]. Nature Reviews Chemistry, 2024, 8(6): 471-485.

[46]  LI D，LIAW P K，XIE L，et al.  Advanced high-entropy alloys breaking the property limits of current materials [J]. Journal of Materials Science & Technology, 2024, 186: 219-230.

[47]  AN Z，MAO S，YANG T，et al. Simultaneously enhanced oxidation resistance and mechanical properties in a novel lightweight Ti2VZrNb0.5Al0.5 high-entropy alloy [J]. Science China Materials, 2022, 65(10): 2842-2849.

[48]  TONG Y，ZHAO S，BEI H，et al. Severe local lattice distortion in Zr- and/or Hf-containing refractory multi-principal element alloys [J]. Acta Materialia, 2020, 183: 172-181.

[49]  SENKOV O N，SEMIATIN S L.  Microstructure and properties of a refractory high-entropy alloy after cold working [J]. Journal of Alloys and Compounds, 2015, 649: 1110-1123.

[50]  WANG S P，MA E，XU J J I.  New ternary equi-atomic refractory medium-entropy alloys with tensile ductility: Hafnium versus titanium into NbTa-based solution [J]. Intermetallics, 2019, 107: 15-23.

[51]  HAN Z，MENG L，YANG J，et al. Novel BCC VNbTa refractory multi-element alloys with superior tensile properties [J]. Materials Science and Engineering: A, 2021, 825: 141908.

[52]  LAI W，LIU H，YU X，et al. A design of TiZr-rich body-centered cubic structured multi-principal element alloys with outstanding tensile strength and ductility [J]. Materials Science and Engineering: A, 2021, 813: 141135.

[53]  LAI W，VOGEL F，ZHAO X，et al. Design of BCC refractory multi-principal element alloys with superior mechanical properties [J]. Materials Research Letters, 2022, 10(3): 133-140.

[54]  SHEIKH S，SHAFEIE S，HU Q，et al. Alloy design for intrinsically ductile refractory high-entropy alloys [J]. Journal of Applied Physics, 2016, 120(16): 164902.

[55]  WU Z，BEI H，PHARR G M，et al. Temperature dependence of the mechanical properties of equiatomic solid solution alloys with face-centered cubic crystal structures [J]. Acta Materialia, 2014, 81: 428-441.

[56] MA E，WU X. Tailoring heterogeneities in high-entropy alloys to promote strength–ductility synergy [J]. Nature Communications, 2019, 10(1): 5623.

[57]  LI Q J，SHENG H，MA E. Strengthening in multi-principal element alloys with local-chemical-order roughened dislocation pathways [J]. Nature Communications, 2019, 10(1): 3563.

[58]  WU X. Chemical short-range orders in high-/medium-entropy alloys [J]. Journal of Materials Science & Technology, 2023, 147: 189-196.

[59]  XUN K，ZHANG B，WANG Q，et al. Local chemical inhomogeneities in TiZrNb-based refractory high-entropy alloys [J]. Journal of Materials Science & Technology, 2023, 135: 221-230.

[60]  余倩，陈雨洁，方研. 高熵合金中的元素分布规律及其作用[J]. 金属学报，2021，57(4): 393-402.

[61]  WANG L，DING J，CHEN S，et al. Tailoring planar slip to achieve pure metal-like ductility in body-centred-cubic multi-principal element alloys [J]. Nature Materials, 2023, 22(8): 950-957.

[62]  ZHOU L，WANG Q，WANG J，et al. Atomic-scale evidence of chemical short-range order in CrCoNi medium-entropy alloy [J]. Acta Materialia, 2022, 224: 117490.

[63]  WANG L，HAN X，LIU P，et al. In situ observation of dislocation behavior in nanometer grains [J].  Physical Review Letters, 2010, 105(13): 135501.

[64]  LI X，WEI Y，LU L，et al. Dislocation nucleation governed softening and maximum strength in nano-twinned metals [J]. Nature, 2010, 464(7290): 877-880.

[65]  YEH J W. Strength through high slip-plane density [J]. Science, 2021, 374(6570): 940-941.

[66]  CAILLARD D. A TEM in situ study of alloying effects in iron. I—Solid solution softening caused by low concentrations of Ni, Si and Cr [J].  Acta Materialia, 2013, 61(8): 2793-2807.

[67]  CAILLARD D.  A TEM in situ study of alloying effects in iron. II—Solid solution hardening caused by high concentrations of Si and Cr [J]. Acta Materialia, 2013, 61(8): 2808-2827.

[68]  YIN S，DING J，ASTA M，et al. Ab initio modeling of the role of local chemical short-range order on the Peierls potential of screw dislocations in bodycentered cubic high-entropy alloys [J]. arXiv Preprint arXiv:1912.10506, 2019.

[69]  GUO S，LIU C T. Phase stability in high entropy alloys: Formation of solid-solution phase or amorphous phase [J]. Progress in Natural Science: Materials International, 2011, 21(6): 433-446.

[70]  DASARI S，SHARMA A，JIANG C，et al. Exceptional enhancement of mechanical properties in high-entropy alloys via thermodynamically guided local chemical ordering [J]. Proceedings of the National Academy of Sciences, 2023, 120(23): e2211787120.

[71]  SENKOV O N，WILKS G B，SCOTT J M，et al. Mechanical properties of Nb₂₅Mo₂₅Ta₂₅W₂₅ and V₂₀Nb₂₀Mo₂₀Ta₂₀W₂₀ refractory high entropy alloys [J]. Intermetallics, 2011, 19(5): 698-706.

[72]  RASOOLI N，CHEN W，DALY M J N. Deformation mechanisms in high entropy alloys: a minireview of short-range order effects [J].  2024, 16(4): 1650-1663.

[73]  BASINSKI Z S，SZCZERBA M S，EMBURY J D. Tensile instability in face-centred cubic materials [J]. Philosophical Magazine A, 1997, 76(4): 743-752.

[74]  MA E. Unusual dislocation behavior in high-entropy alloys [J]. Scripta Materialia, 2020, 181: 127-133.

[75]  MA E，ZHU T. Towards strength–ductility synergy through the design of heterogeneous nanostructures in metals [J]. Materials Today, 2017, 20(6): 323-331.

[76]  XU B，DUAN H，CHEN X，et al. Harnessing instability for work hardening in multi-principal element alloys [J]. Nature Materials, 2024, 23(6): 755-761.

[77]  ZHU Q，HUANG Q，TIAN Y，et al. Hierarchical twinning governed by defective twin boundary in metallic materials [J]. Science Advances, 2022, 8(20): eabn8299.

[78]  WEI Y，LI Y，ZHU L，et al. Evading the strength–ductility trade-off dilemma in steel through gradient hierarchical nanotwins [J]. Nature Communications, 2014, 5(1): 3580.

[79]  LI Z，PRADEEP K G，DENG Y，et al.  Metastable high-entropy dual-phase alloys overcome the strength–ductility trade-off [J].  Nature, 2016, 534(7606): 227-230.

[80]  AN Z，MAO S，LIU Y，et al. Inherent and multiple strain hardening imparting synergistic ultrahigh strength and ductility in a low stacking faulted heterogeneous high-entropy alloy [J]. Acta Materialia, 2023, 243:118516.

[81]  ARORA G，AIDHY D S. Machine learning enabled prediction of stacking fault energies in concentrated alloys [J]. Metals, 2020,10(8):1072.

[82]  LIU S F，WU Y，WANG H T，et al. Stacking fault energy of face-centered-cubic high entropy alloys [J]. Intermetallics, 2018, 93: 269-273.

[83]  KHAN T Z，KIRK T，VAZQUEZ G，et al. Towards stacking fault energy engineering in FCC high entropy alloys [J]. Acta Materialia, 2022, 224: 117472.

[84]  DING J，YU Q，ASTA M，et al. Tunable stacking fault energies by tailoring local chemical order in CrCoNi medium-entropy alloys [J]. Proceedings of the National Academy of Sciences, 2018, 115(36): 8919-8924.

[85]  XU D，WANG M，LI T，et al. A critical review of the mechanical properties of CoCrNi-based medium-entropy alloys [J]. Microstructures, 2022, 2(1): 2022001.

[86]  SENKOV O N，MIRACLE D B，CHAPUT K J，et al. Development and exploration of refractory high entropy alloys—A review [J]. Journal of materials research, 2018, 33(19): 3092-3128.

[87]  韩晓东, 王立华, 张泽.  原子分辨的材料力学行为实验系统与晶界塑性原子机制[J]. 电子显微学报, 2023, 42(4): 543-564.

[88]  DU X H，LI W P，CHANG H T，et al. Dual heterogeneous structures lead to ultrahigh strength and uniform ductility in a Co-Cr-Ni medium-entropy alloy [J]. Nature Communications, 2020, 11(1): 2390.

[89]  YANG M，YAN D，YUAN F，et al. Dynamically reinforced heterogeneous grain structure prolongs ductility in a medium-entropy alloy with gigapascal yield strength [J]. Proceedings of the National Academy of Sciences, 2018, 115(28): 7224-7229.