Fracture behavior and KR-curve characteristics of nuclear graphite IG11 under three-point bending tests

IF 3.2 2区工程技术 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY Journal of Nuclear Materials Pub Date : 2025-04-01 Epub Date: 2025-03-01 DOI:10.1016/j.jnucmat.2025.155724

Hengchang Liu , Jie Shen , Jing Chen , Hongniao Chen , Yuxiang Tang

{"title":"Fracture behavior and KR-curve characteristics of nuclear graphite IG11 under three-point bending tests","authors":"Hengchang Liu , Jie Shen , Jing Chen , Hongniao Chen , Yuxiang Tang","doi":"10.1016/j.jnucmat.2025.155724","DOIUrl":null,"url":null,"abstract":"<div><div>Three-point bending tests were conducted on single edge center-notched beams to study the fracture behavior of nuclear graphite IG11. Full-field information of surface deformation of the specimens was measured by digital image correlation (DIC) technique while internal micro-cracks and damage of the specimen were monitored using acoustic emission (AE) technique. The initiation and evolution of crack and fracture process zone (FPZ) were studied and the factors affecting the behavior of KR-curves were investigated. Based on the test results, fracture toughness KIc and fracture energy GFP-δ of IG11 graphite were determined and the FPZ length was quantitatively evaluated using the strain thresholds. The FPZ initiated at 55 % of the peak load and preceded the crack initiation. The evolution of the FPZ showed three phases and reached the maximum at approximately 75 % of Pc in post-peak stage with a length of 8.43 ± 0.41 mm. The obtained KR-curves showed typical three stages: an initial rise, a stable plateau and a final decrease. The effect of the FPZ length on KR-curve behavior was discussed and factors affecting the behavior of the KR-curve were analyzed, including the length of the bridging zone, the test type and the grain size.</div></div>","PeriodicalId":373,"journal":{"name":"Journal of Nuclear Materials","volume":"608 ","pages":"Article 155724"},"PeriodicalIF":3.2000,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Nuclear Materials","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0022311525001199","RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2025/3/1 0:00:00","PubModel":"Epub","JCR":"Q3","JCRName":"MATERIALS SCIENCE, MULTIDISCIPLINARY","Score":null,"Total":0}

引用次数: 0

Abstract

Three-point bending tests were conducted on single edge center-notched beams to study the fracture behavior of nuclear graphite IG11. Full-field information of surface deformation of the specimens was measured by digital image correlation (DIC) technique while internal micro-cracks and damage of the specimen were monitored using acoustic emission (AE) technique. The initiation and evolution of crack and fracture process zone (FPZ) were studied and the factors affecting the behavior of K_R-curves were investigated. Based on the test results, fracture toughness K_Ic and fracture energy G_F^P-δ of IG11 graphite were determined and the FPZ length was quantitatively evaluated using the strain thresholds. The FPZ initiated at 55 % of the peak load and preceded the crack initiation. The evolution of the FPZ showed three phases and reached the maximum at approximately 75 % of P_c in post-peak stage with a length of 8.43 ± 0.41 mm. The obtained K_R-curves showed typical three stages: an initial rise, a stable plateau and a final decrease. The effect of the FPZ length on K_R-curve behavior was discussed and factors affecting the behavior of the K_R-curve were analyzed, including the length of the bridging zone, the test type and the grain size.

查看原文

微信好友朋友圈 QQ好友复制链接

本刊更多论文

核石墨IG11三点弯曲断裂行为及kr曲线特征

采用单边中心缺口梁进行三点弯曲试验，研究了核石墨IG11的断裂行为。采用数字图像相关（DIC）技术测量试件表面变形的全场信息，采用声发射（AE）技术监测试件内部微裂纹和损伤情况。研究了裂纹和断裂过程区（FPZ）的起裂和演化过程，探讨了影响kr曲线行为的因素。根据试验结果，测定了IG11石墨的断裂韧性KIc和断裂能GFP-δ，并利用应变阈值定量评价了其断裂韧性长度。FPZ在峰值荷载的55%处开始萌生，并且先于裂纹萌生。FPZ的演化分为三个阶段，峰后阶段在Pc的75%左右达到最大值，长度为8.43±0.41 mm。得到的kr -曲线表现出典型的三个阶段：初始上升、稳定平台和最终下降。讨论了FPZ长度对kr -曲线行为的影响，分析了影响kr -曲线行为的因素，包括桥接区长度、试验类型和晶粒尺寸。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文去求助

来源期刊

Journal of Nuclear Materials 工程技术-材料科学：综合

CiteScore

5.70

自引率

25.80%

发文量

601

审稿时长

63 days

期刊介绍： The Journal of Nuclear Materials publishes high quality papers in materials research for nuclear applications, primarily fission reactors, fusion reactors, and similar environments including radiation areas of charged particle accelerators. Both original research and critical review papers covering experimental, theoretical, and computational aspects of either fundamental or applied nature are welcome. The breadth of the field is such that a wide range of processes and properties in the field of materials science and engineering is of interest to the readership, spanning atom-scale processes, microstructures, thermodynamics, mechanical properties, physical properties, and corrosion, for example. Topics covered by JNM Fission reactor materials, including fuels, cladding, core structures, pressure vessels, coolant interactions with materials, moderator and control components, fission product behavior. Materials aspects of the entire fuel cycle. Materials aspects of the actinides and their compounds. Performance of nuclear waste materials; materials aspects of the immobilization of wastes. Fusion reactor materials, including first walls, blankets, insulators and magnets. Neutron and charged particle radiation effects in materials, including defects, transmutations, microstructures, phase changes and macroscopic properties. Interaction of plasmas, ion beams, electron beams and electromagnetic radiation with materials relevant to nuclear systems.