{"title":"简化Fe-Ni-Cr合金体系辐照损伤及氦效应的分子动力学研究:与合金800H相关","authors":"T.P. Kaloni, I. Cheik Njifon, E. Torres","doi":"10.1016/j.nimb.2025.165871","DOIUrl":null,"url":null,"abstract":"<div><div>Fe–Ni–Cr alloy 800H is a critical structural material in nuclear reactors. Under irradiation, it faces significant challenges due to defect formation and Helium (He) generation, which adversely affect its microstructure and durability. In this study, we conducted molecular dynamics simulations of the combined effects of He and irradiation in polycrystalline Fe–Ni–Cr alloy 800H. Our findings show that irradiation induces the transition of the polycrystals into a single crystal. However, increasing the number of grains and He concentration favored the polycrystalline state. We also observe a decrease in the number of dislocations and an increase in large defects with the increase of the He content. Our structural evaluations reveal that He clusters mainly accumulate at those large defects, which are surrounded by dislocation loops. The interplay between the formation of He clusters and irradiation damage results in substantially deteriorating the mechanical properties of Fe–Ni–Cr alloy 800H structures. Our simulations provide valuable insights into the degradation mechanisms under the combined effects of He and irradiation damage.</div></div>","PeriodicalId":19380,"journal":{"name":"Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms","volume":"569 ","pages":"Article 165871"},"PeriodicalIF":1.4000,"publicationDate":"2025-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Molecular dynamics study of irradiation damage and helium effects in a simplified Fe–Ni–Cr alloy system: Relevant to alloy 800H\",\"authors\":\"T.P. Kaloni, I. Cheik Njifon, E. Torres\",\"doi\":\"10.1016/j.nimb.2025.165871\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>Fe–Ni–Cr alloy 800H is a critical structural material in nuclear reactors. Under irradiation, it faces significant challenges due to defect formation and Helium (He) generation, which adversely affect its microstructure and durability. In this study, we conducted molecular dynamics simulations of the combined effects of He and irradiation in polycrystalline Fe–Ni–Cr alloy 800H. Our findings show that irradiation induces the transition of the polycrystals into a single crystal. However, increasing the number of grains and He concentration favored the polycrystalline state. We also observe a decrease in the number of dislocations and an increase in large defects with the increase of the He content. Our structural evaluations reveal that He clusters mainly accumulate at those large defects, which are surrounded by dislocation loops. The interplay between the formation of He clusters and irradiation damage results in substantially deteriorating the mechanical properties of Fe–Ni–Cr alloy 800H structures. Our simulations provide valuable insights into the degradation mechanisms under the combined effects of He and irradiation damage.</div></div>\",\"PeriodicalId\":19380,\"journal\":{\"name\":\"Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms\",\"volume\":\"569 \",\"pages\":\"Article 165871\"},\"PeriodicalIF\":1.4000,\"publicationDate\":\"2025-10-04\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms\",\"FirstCategoryId\":\"101\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0168583X25002617\",\"RegionNum\":3,\"RegionCategory\":\"物理与天体物理\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"INSTRUMENTS & INSTRUMENTATION\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms","FirstCategoryId":"101","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0168583X25002617","RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"INSTRUMENTS & INSTRUMENTATION","Score":null,"Total":0}
Molecular dynamics study of irradiation damage and helium effects in a simplified Fe–Ni–Cr alloy system: Relevant to alloy 800H
Fe–Ni–Cr alloy 800H is a critical structural material in nuclear reactors. Under irradiation, it faces significant challenges due to defect formation and Helium (He) generation, which adversely affect its microstructure and durability. In this study, we conducted molecular dynamics simulations of the combined effects of He and irradiation in polycrystalline Fe–Ni–Cr alloy 800H. Our findings show that irradiation induces the transition of the polycrystals into a single crystal. However, increasing the number of grains and He concentration favored the polycrystalline state. We also observe a decrease in the number of dislocations and an increase in large defects with the increase of the He content. Our structural evaluations reveal that He clusters mainly accumulate at those large defects, which are surrounded by dislocation loops. The interplay between the formation of He clusters and irradiation damage results in substantially deteriorating the mechanical properties of Fe–Ni–Cr alloy 800H structures. Our simulations provide valuable insights into the degradation mechanisms under the combined effects of He and irradiation damage.
期刊介绍:
Section B of Nuclear Instruments and Methods in Physics Research covers all aspects of the interaction of energetic beams with atoms, molecules and aggregate forms of matter. This includes ion beam analysis and ion beam modification of materials as well as basic data of importance for these studies. Topics of general interest include: atomic collisions in solids, particle channelling, all aspects of collision cascades, the modification of materials by energetic beams, ion implantation, irradiation - induced changes in materials, the physics and chemistry of beam interactions and the analysis of materials by all forms of energetic radiation. Modification by ion, laser and electron beams for the study of electronic materials, metals, ceramics, insulators, polymers and other important and new materials systems are included. Related studies, such as the application of ion beam analysis to biological, archaeological and geological samples as well as applications to solve problems in planetary science are also welcome. Energetic beams of interest include atomic and molecular ions, neutrons, positrons and muons, plasmas directed at surfaces, electron and photon beams, including laser treated surfaces and studies of solids by photon radiation from rotating anodes, synchrotrons, etc. In addition, the interaction between various forms of radiation and radiation-induced deposition processes are relevant.