Fei Chen, Fei Liu, Yuan-Biao Tan, Wei Shi, Xuan-Ming Ji, Hao Fu, Si-Yuan Wei, Song Xiang
{"title":"低温下铁钴铬镍钼 0.2 高熵合金中通过纳米孪晶和相变介导的锯齿状流动行为","authors":"Fei Chen, Fei Liu, Yuan-Biao Tan, Wei Shi, Xuan-Ming Ji, Hao Fu, Si-Yuan Wei, Song Xiang","doi":"10.1007/s12598-024-03154-1","DOIUrl":null,"url":null,"abstract":"<div><p>The serrated flow behavior, known as the Portevin–Le Chatelier (PLC) effect, is commonly observed during high-temperature deformation. In this study, we report a serrated flow behavior in FeCoCrNiMo0.2 high-entropy alloy (HEA), which is mediated by nano-twinning and phase transformation at cryogenic temperatures. During uniaxial tensile deformation at 77 K, the alloy exhibited the formation of high-density deformation nano-twinning, cross-twinning, stacking faults (SFs) and Lomer–Cottrell locks (L-C locks). Additionally, the lower stacking fault energy (SFE) at low temperatures promotes the formation of the 9R phase. The high-density twin boundaries effectively hinder dislocation movement, leading to the instability of plastic deformation and promoting the serrated flow behavior. Furthermore, the rapid and unstable transformation of the 9R phase contributes to the pronounced serrated flow behavior. Nano-twinning, SFs, cross-twinning, L-C locks and 9R phase collectively induce a dynamic Hall–Petch effect, enhancing the strength-ductility synergy and strain-hardening ability of deformed alloy at 77 K. Our work provides valuable insights into the mechanism of tensile deformation at cryogenic temperatures in single-phase FCC HEA.</p><h3>Graphical abstract</h3>\n<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":749,"journal":{"name":"Rare Metals","volume":"44 5","pages":"3447 - 3459"},"PeriodicalIF":9.6000,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Serrated flow behavior mediated via nano-twinning and phase transformation in FeCoCrNiMo0.2 high-entropy alloy at cryogenic temperatures\",\"authors\":\"Fei Chen, Fei Liu, Yuan-Biao Tan, Wei Shi, Xuan-Ming Ji, Hao Fu, Si-Yuan Wei, Song Xiang\",\"doi\":\"10.1007/s12598-024-03154-1\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>The serrated flow behavior, known as the Portevin–Le Chatelier (PLC) effect, is commonly observed during high-temperature deformation. In this study, we report a serrated flow behavior in FeCoCrNiMo0.2 high-entropy alloy (HEA), which is mediated by nano-twinning and phase transformation at cryogenic temperatures. During uniaxial tensile deformation at 77 K, the alloy exhibited the formation of high-density deformation nano-twinning, cross-twinning, stacking faults (SFs) and Lomer–Cottrell locks (L-C locks). Additionally, the lower stacking fault energy (SFE) at low temperatures promotes the formation of the 9R phase. The high-density twin boundaries effectively hinder dislocation movement, leading to the instability of plastic deformation and promoting the serrated flow behavior. Furthermore, the rapid and unstable transformation of the 9R phase contributes to the pronounced serrated flow behavior. Nano-twinning, SFs, cross-twinning, L-C locks and 9R phase collectively induce a dynamic Hall–Petch effect, enhancing the strength-ductility synergy and strain-hardening ability of deformed alloy at 77 K. Our work provides valuable insights into the mechanism of tensile deformation at cryogenic temperatures in single-phase FCC HEA.</p><h3>Graphical abstract</h3>\\n<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>\",\"PeriodicalId\":749,\"journal\":{\"name\":\"Rare Metals\",\"volume\":\"44 5\",\"pages\":\"3447 - 3459\"},\"PeriodicalIF\":9.6000,\"publicationDate\":\"2025-02-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Rare Metals\",\"FirstCategoryId\":\"88\",\"ListUrlMain\":\"https://link.springer.com/article/10.1007/s12598-024-03154-1\",\"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":"Rare Metals","FirstCategoryId":"88","ListUrlMain":"https://link.springer.com/article/10.1007/s12598-024-03154-1","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}
Serrated flow behavior mediated via nano-twinning and phase transformation in FeCoCrNiMo0.2 high-entropy alloy at cryogenic temperatures
The serrated flow behavior, known as the Portevin–Le Chatelier (PLC) effect, is commonly observed during high-temperature deformation. In this study, we report a serrated flow behavior in FeCoCrNiMo0.2 high-entropy alloy (HEA), which is mediated by nano-twinning and phase transformation at cryogenic temperatures. During uniaxial tensile deformation at 77 K, the alloy exhibited the formation of high-density deformation nano-twinning, cross-twinning, stacking faults (SFs) and Lomer–Cottrell locks (L-C locks). Additionally, the lower stacking fault energy (SFE) at low temperatures promotes the formation of the 9R phase. The high-density twin boundaries effectively hinder dislocation movement, leading to the instability of plastic deformation and promoting the serrated flow behavior. Furthermore, the rapid and unstable transformation of the 9R phase contributes to the pronounced serrated flow behavior. Nano-twinning, SFs, cross-twinning, L-C locks and 9R phase collectively induce a dynamic Hall–Petch effect, enhancing the strength-ductility synergy and strain-hardening ability of deformed alloy at 77 K. Our work provides valuable insights into the mechanism of tensile deformation at cryogenic temperatures in single-phase FCC HEA.
期刊介绍:
Rare Metals is a monthly peer-reviewed journal published by the Nonferrous Metals Society of China. It serves as a platform for engineers and scientists to communicate and disseminate original research articles in the field of rare metals. The journal focuses on a wide range of topics including metallurgy, processing, and determination of rare metals. Additionally, it showcases the application of rare metals in advanced materials such as superconductors, semiconductors, composites, and ceramics.