Aurélie Jacob, Bernd Schuscha, Philipp Retzl, Yao V. Shan, Ernst Kozeschnik
{"title":"碳对贝氏体形成影响的热力学预测,包括BCT相变","authors":"Aurélie Jacob, Bernd Schuscha, Philipp Retzl, Yao V. Shan, Ernst Kozeschnik","doi":"10.1007/s11669-023-01067-7","DOIUrl":null,"url":null,"abstract":"<div><p>There exists strong experimental evidence that bainitic ferrite is formed as a supersaturated solid solution of carbon within a tetragonally-distorted body-centered iron structure (BCT), where carbon preferentially occupies the octahedral site. Despite this, the BCT structure has not yet been accounted for in the computational analysis of the thermodynamics of the bainite transformation. In the present work, we propose to calculate the onset of the bainite transformation based on the <i>T</i><sub>0</sub>′ concept, including the effect of Zener-ordering. This mechanism stabilizes the BCT structure, makes it energetically more favorable than BCC and leads to a significantly higher solubility of C compared Fe-BCC. The computational predictions are made based on a recent reassessment of low-T Gibbs energies and finally compared to experiments. The important role of C is emphasized, with the Fe-C system used as a showcase.</p></div>","PeriodicalId":657,"journal":{"name":"Journal of Phase Equilibria and Diffusion","volume":"44 6","pages":"729 - 737"},"PeriodicalIF":1.5000,"publicationDate":"2023-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11669-023-01067-7.pdf","citationCount":"0","resultStr":"{\"title\":\"Thermodynamic Prediction of the Impact of Carbon on Bainite Formation, Including the BCT Transformation\",\"authors\":\"Aurélie Jacob, Bernd Schuscha, Philipp Retzl, Yao V. Shan, Ernst Kozeschnik\",\"doi\":\"10.1007/s11669-023-01067-7\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>There exists strong experimental evidence that bainitic ferrite is formed as a supersaturated solid solution of carbon within a tetragonally-distorted body-centered iron structure (BCT), where carbon preferentially occupies the octahedral site. Despite this, the BCT structure has not yet been accounted for in the computational analysis of the thermodynamics of the bainite transformation. In the present work, we propose to calculate the onset of the bainite transformation based on the <i>T</i><sub>0</sub>′ concept, including the effect of Zener-ordering. This mechanism stabilizes the BCT structure, makes it energetically more favorable than BCC and leads to a significantly higher solubility of C compared Fe-BCC. The computational predictions are made based on a recent reassessment of low-T Gibbs energies and finally compared to experiments. The important role of C is emphasized, with the Fe-C system used as a showcase.</p></div>\",\"PeriodicalId\":657,\"journal\":{\"name\":\"Journal of Phase Equilibria and Diffusion\",\"volume\":\"44 6\",\"pages\":\"729 - 737\"},\"PeriodicalIF\":1.5000,\"publicationDate\":\"2023-12-06\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://link.springer.com/content/pdf/10.1007/s11669-023-01067-7.pdf\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Phase Equilibria and Diffusion\",\"FirstCategoryId\":\"88\",\"ListUrlMain\":\"https://link.springer.com/article/10.1007/s11669-023-01067-7\",\"RegionNum\":4,\"RegionCategory\":\"材料科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q4\",\"JCRName\":\"CHEMISTRY, PHYSICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Phase Equilibria and Diffusion","FirstCategoryId":"88","ListUrlMain":"https://link.springer.com/article/10.1007/s11669-023-01067-7","RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
Thermodynamic Prediction of the Impact of Carbon on Bainite Formation, Including the BCT Transformation
There exists strong experimental evidence that bainitic ferrite is formed as a supersaturated solid solution of carbon within a tetragonally-distorted body-centered iron structure (BCT), where carbon preferentially occupies the octahedral site. Despite this, the BCT structure has not yet been accounted for in the computational analysis of the thermodynamics of the bainite transformation. In the present work, we propose to calculate the onset of the bainite transformation based on the T0′ concept, including the effect of Zener-ordering. This mechanism stabilizes the BCT structure, makes it energetically more favorable than BCC and leads to a significantly higher solubility of C compared Fe-BCC. The computational predictions are made based on a recent reassessment of low-T Gibbs energies and finally compared to experiments. The important role of C is emphasized, with the Fe-C system used as a showcase.
期刊介绍:
The most trusted journal for phase equilibria and thermodynamic research, ASM International''s Journal of Phase Equilibria and Diffusion features critical phase diagram evaluations on scientifically and industrially important alloy systems, authored by international experts.
The Journal of Phase Equilibria and Diffusion is critically reviewed and contains basic and applied research results, a survey of current literature and other pertinent articles. The journal covers the significance of diagrams as well as new research techniques, equipment, data evaluation, nomenclature, presentation and other aspects of phase diagram preparation and use.
Content includes information on phenomena such as kinetic control of equilibrium, coherency effects, impurity effects, and thermodynamic and crystallographic characteristics. The journal updates systems previously published in the Bulletin of Alloy Phase Diagrams as new data are discovered.