{"title":"原位同步加速器x射线微衍射研究了7075铝基喷丸缺口在拉伸载荷作用下的局部应变场演化","authors":"Aitor Madariaga , Eduardo Vazquez , Daniel Foster , Enrique Jimenez-Melero","doi":"10.1016/j.jallcom.2025.182861","DOIUrl":null,"url":null,"abstract":"<div><div>Shot peening (SP) is commonly applied to Al-base alloys during manufacture to enhance their fatigue tolerance and notch sensitivity in aerospace engineering components with geometrical discontinuities. We have mapped with high spatial resolution the local strain field induced by surface shot peening around notches in aerospace 7050-T7451 alloy, and determined the local mechanical behaviour of the surface affected layer during room-temperature tensile testing. For this purpose, we have performed in-situ synchrotron X-ray µ-diffraction during tensile loading of notched specimens in the as-machined condition, and also for two different shot peening intensities. The behaviour of the notched specimen not affected by machining and SP was also simulated by finite element modelling to decouple the local surface mechanical response from the bulk material behaviour. The results confirmed that shot peening induces compressive residual stresses close to the notch tip, and also changes in notch geometry and surface topography. Shot-peened surfaces experience accommodation of plastic effects at the early stages of the tensile test, and they yielded at ∼70–80 % higher applied nominal tensile stresses than the as-machined material. When increasing the applied stress, the maximum longitudinal elastic strain shifts beneath the surface, and the magnitude of the peak strain and its position converge to the same value for the as-machined and shot-peened specimens. Beyond yielding, there is an exponential increase in plastic strain close to the notch tip, irrespective of the initial surface condition. The overall elasto-plastic response of the material is not affected by shot peening, but compressive residual strains significantly retard yielding close to the notch tip under loading.</div></div>","PeriodicalId":344,"journal":{"name":"Journal of Alloys and Compounds","volume":"1039 ","pages":"Article 182861"},"PeriodicalIF":6.3000,"publicationDate":"2025-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Local strain field evolution at shot-peened 7075 Al-base notches upon tensile loading using in-situ synchrotron X-ray µ-diffraction\",\"authors\":\"Aitor Madariaga , Eduardo Vazquez , Daniel Foster , Enrique Jimenez-Melero\",\"doi\":\"10.1016/j.jallcom.2025.182861\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>Shot peening (SP) is commonly applied to Al-base alloys during manufacture to enhance their fatigue tolerance and notch sensitivity in aerospace engineering components with geometrical discontinuities. We have mapped with high spatial resolution the local strain field induced by surface shot peening around notches in aerospace 7050-T7451 alloy, and determined the local mechanical behaviour of the surface affected layer during room-temperature tensile testing. For this purpose, we have performed in-situ synchrotron X-ray µ-diffraction during tensile loading of notched specimens in the as-machined condition, and also for two different shot peening intensities. The behaviour of the notched specimen not affected by machining and SP was also simulated by finite element modelling to decouple the local surface mechanical response from the bulk material behaviour. The results confirmed that shot peening induces compressive residual stresses close to the notch tip, and also changes in notch geometry and surface topography. Shot-peened surfaces experience accommodation of plastic effects at the early stages of the tensile test, and they yielded at ∼70–80 % higher applied nominal tensile stresses than the as-machined material. When increasing the applied stress, the maximum longitudinal elastic strain shifts beneath the surface, and the magnitude of the peak strain and its position converge to the same value for the as-machined and shot-peened specimens. Beyond yielding, there is an exponential increase in plastic strain close to the notch tip, irrespective of the initial surface condition. The overall elasto-plastic response of the material is not affected by shot peening, but compressive residual strains significantly retard yielding close to the notch tip under loading.</div></div>\",\"PeriodicalId\":344,\"journal\":{\"name\":\"Journal of Alloys and Compounds\",\"volume\":\"1039 \",\"pages\":\"Article 182861\"},\"PeriodicalIF\":6.3000,\"publicationDate\":\"2025-08-07\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Alloys and Compounds\",\"FirstCategoryId\":\"88\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0925838825044226\",\"RegionNum\":2,\"RegionCategory\":\"材料科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"CHEMISTRY, PHYSICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Alloys and Compounds","FirstCategoryId":"88","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0925838825044226","RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
Local strain field evolution at shot-peened 7075 Al-base notches upon tensile loading using in-situ synchrotron X-ray µ-diffraction
Shot peening (SP) is commonly applied to Al-base alloys during manufacture to enhance their fatigue tolerance and notch sensitivity in aerospace engineering components with geometrical discontinuities. We have mapped with high spatial resolution the local strain field induced by surface shot peening around notches in aerospace 7050-T7451 alloy, and determined the local mechanical behaviour of the surface affected layer during room-temperature tensile testing. For this purpose, we have performed in-situ synchrotron X-ray µ-diffraction during tensile loading of notched specimens in the as-machined condition, and also for two different shot peening intensities. The behaviour of the notched specimen not affected by machining and SP was also simulated by finite element modelling to decouple the local surface mechanical response from the bulk material behaviour. The results confirmed that shot peening induces compressive residual stresses close to the notch tip, and also changes in notch geometry and surface topography. Shot-peened surfaces experience accommodation of plastic effects at the early stages of the tensile test, and they yielded at ∼70–80 % higher applied nominal tensile stresses than the as-machined material. When increasing the applied stress, the maximum longitudinal elastic strain shifts beneath the surface, and the magnitude of the peak strain and its position converge to the same value for the as-machined and shot-peened specimens. Beyond yielding, there is an exponential increase in plastic strain close to the notch tip, irrespective of the initial surface condition. The overall elasto-plastic response of the material is not affected by shot peening, but compressive residual strains significantly retard yielding close to the notch tip under loading.
期刊介绍:
The Journal of Alloys and Compounds is intended to serve as an international medium for the publication of work on solid materials comprising compounds as well as alloys. Its great strength lies in the diversity of discipline which it encompasses, drawing together results from materials science, solid-state chemistry and physics.