{"title":"高熵合金中的化学不均匀性有助于缓解强度-电导率权衡问题","authors":"Evan Ma , Chang Liu","doi":"10.1016/j.pmatsci.2024.101252","DOIUrl":null,"url":null,"abstract":"<div><p>Metallurgists have long been accustomed to a trade-off between yield strength and tensile ductility. Extending previously known strain-hardening mechanisms, the emerging multi-principal-element alloys (MPEAs) offer additional help in promoting the strength-ductility synergy, towards gigapascal yield strength simultaneously with pure-metal-like tensile ductility. The highly concentrated chemical make-up in these “high-entropy” alloys (HEAs) adds, at ultrafine spatial scale from sub-nanometer to tens of nanometers, inherent chemical inhomogeneities in local composition and local chemical order (LCO). These institute a “nano-cocktail” environment that exerts extra dragging forces, rendering a much wavier motion of dislocation lines (in stick–slip mode) different from dilute solutions. The variable fault energy landscape also makes the dislocation movement sluggish, increasing their chances to hit one another and react to increase entanglement. The accumulation of dislocations (plus faults) dynamically stores obstacles against ensuing dislocation motion to sustain an adequate strain-hardening rate at high flow stresses, delaying plastic instability to enable large (uniform) elongation. The successes summarized advocate MPEAs as an effective recipe towards ultrahigh strength at little expense of tensile ductility. The insight gained also answers the question as to what new mechanical behavior the HEAs have to offer, beyond what has been well documented for traditional metals and solid solutions.</p></div>","PeriodicalId":411,"journal":{"name":"Progress in Materials Science","volume":null,"pages":null},"PeriodicalIF":33.6000,"publicationDate":"2024-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0079642524000215/pdfft?md5=1fc92435938bebc4ed14ae1c8275f508&pid=1-s2.0-S0079642524000215-main.pdf","citationCount":"0","resultStr":"{\"title\":\"Chemical inhomogeneities in high-entropy alloys help mitigate the strength-ductility trade-off\",\"authors\":\"Evan Ma , Chang Liu\",\"doi\":\"10.1016/j.pmatsci.2024.101252\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>Metallurgists have long been accustomed to a trade-off between yield strength and tensile ductility. Extending previously known strain-hardening mechanisms, the emerging multi-principal-element alloys (MPEAs) offer additional help in promoting the strength-ductility synergy, towards gigapascal yield strength simultaneously with pure-metal-like tensile ductility. The highly concentrated chemical make-up in these “high-entropy” alloys (HEAs) adds, at ultrafine spatial scale from sub-nanometer to tens of nanometers, inherent chemical inhomogeneities in local composition and local chemical order (LCO). These institute a “nano-cocktail” environment that exerts extra dragging forces, rendering a much wavier motion of dislocation lines (in stick–slip mode) different from dilute solutions. The variable fault energy landscape also makes the dislocation movement sluggish, increasing their chances to hit one another and react to increase entanglement. The accumulation of dislocations (plus faults) dynamically stores obstacles against ensuing dislocation motion to sustain an adequate strain-hardening rate at high flow stresses, delaying plastic instability to enable large (uniform) elongation. The successes summarized advocate MPEAs as an effective recipe towards ultrahigh strength at little expense of tensile ductility. The insight gained also answers the question as to what new mechanical behavior the HEAs have to offer, beyond what has been well documented for traditional metals and solid solutions.</p></div>\",\"PeriodicalId\":411,\"journal\":{\"name\":\"Progress in Materials Science\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":33.6000,\"publicationDate\":\"2024-02-14\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://www.sciencedirect.com/science/article/pii/S0079642524000215/pdfft?md5=1fc92435938bebc4ed14ae1c8275f508&pid=1-s2.0-S0079642524000215-main.pdf\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Progress in Materials Science\",\"FirstCategoryId\":\"88\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0079642524000215\",\"RegionNum\":1,\"RegionCategory\":\"材料科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"MATERIALS SCIENCE, MULTIDISCIPLINARY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Progress in Materials Science","FirstCategoryId":"88","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0079642524000215","RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATERIALS SCIENCE, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
摘要
长期以来,冶金学家习惯于在屈服强度和拉伸延展性之间进行权衡。新出现的多主元素合金(MPEAs)扩展了之前已知的应变硬化机制,在促进强度-延展性协同作用方面提供了额外的帮助,使屈服强度达到千兆帕,同时具有纯金属般的拉伸延展性。这些 "高熵 "合金(HEAs)中高度集中的化学成分,在亚纳米到数十纳米的超精细空间尺度上,增加了局部成分和局部化学有序性(LCO)中固有的化学不均匀性。这些因素形成了一种 "纳米鸡尾 "环境,施加了额外的拖曳力,使位错线的运动(粘滑模式)与稀释溶液的运动不同。多变的断层能量景观也使差排运动变得迟缓,增加了它们相互碰撞和反应以增加纠缠的机会。位错(加上断层)的积累动态地储存了阻碍位错运动的障碍物,从而在高流动应力下维持足够的应变硬化率,延缓塑性不稳定性,实现大(均匀)伸长。所总结的成功经验表明,MPEA 是在几乎不牺牲拉伸延展性的情况下实现超高强度的有效方法。除了传统金属和固体溶液的文献记载之外,所获得的洞察力还回答了 HEA 可提供哪些新机械性能的问题。
Chemical inhomogeneities in high-entropy alloys help mitigate the strength-ductility trade-off
Metallurgists have long been accustomed to a trade-off between yield strength and tensile ductility. Extending previously known strain-hardening mechanisms, the emerging multi-principal-element alloys (MPEAs) offer additional help in promoting the strength-ductility synergy, towards gigapascal yield strength simultaneously with pure-metal-like tensile ductility. The highly concentrated chemical make-up in these “high-entropy” alloys (HEAs) adds, at ultrafine spatial scale from sub-nanometer to tens of nanometers, inherent chemical inhomogeneities in local composition and local chemical order (LCO). These institute a “nano-cocktail” environment that exerts extra dragging forces, rendering a much wavier motion of dislocation lines (in stick–slip mode) different from dilute solutions. The variable fault energy landscape also makes the dislocation movement sluggish, increasing their chances to hit one another and react to increase entanglement. The accumulation of dislocations (plus faults) dynamically stores obstacles against ensuing dislocation motion to sustain an adequate strain-hardening rate at high flow stresses, delaying plastic instability to enable large (uniform) elongation. The successes summarized advocate MPEAs as an effective recipe towards ultrahigh strength at little expense of tensile ductility. The insight gained also answers the question as to what new mechanical behavior the HEAs have to offer, beyond what has been well documented for traditional metals and solid solutions.
期刊介绍:
Progress in Materials Science is a journal that publishes authoritative and critical reviews of recent advances in the science of materials. The focus of the journal is on the fundamental aspects of materials science, particularly those concerning microstructure and nanostructure and their relationship to properties. Emphasis is also placed on the thermodynamics, kinetics, mechanisms, and modeling of processes within materials, as well as the understanding of material properties in engineering and other applications.
The journal welcomes reviews from authors who are active leaders in the field of materials science and have a strong scientific track record. Materials of interest include metallic, ceramic, polymeric, biological, medical, and composite materials in all forms.
Manuscripts submitted to Progress in Materials Science are generally longer than those found in other research journals. While the focus is on invited reviews, interested authors may submit a proposal for consideration. Non-invited manuscripts are required to be preceded by the submission of a proposal. Authors publishing in Progress in Materials Science have the option to publish their research via subscription or open access. Open access publication requires the author or research funder to meet a publication fee (APC).
Abstracting and indexing services for Progress in Materials Science include Current Contents, Science Citation Index Expanded, Materials Science Citation Index, Chemical Abstracts, Engineering Index, INSPEC, and Scopus.