{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:54:19Z","timestamp":1787028859345,"version":"build-2736575974"},"reference-count":37,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2025,12,17]],"date-time":"2025-12-17T00:00:00Z","timestamp":1765929600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Municipal Natural Science Foundation of Huaian","award":["HAB202366"],"award-info":[{"award-number":["HAB202366"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>This study investigates the effects of multiple laser shock peening (LSP) treatments on the low-cycle fatigue performance and fracture mechanisms of laser-melted, additive-manufactured Ti-6.5Al-1Mo-1V-2Zr (TA15) titanium alloy. The primary objective is to systematically evaluate how different LSP impact numbers (0, 1, and 2 impacts) enhance fatigue life and alter fracture behavior. Low-cycle fatigue life was determined via tensile-compression fatigue testing. Microfracture morphology was examined using scanning electron microscopy (SEM), surface residual stresses were measured by X-ray diffraction (XRD), and microhardness tests were conducted concurrently. Results indicate that LSP significantly enhances fatigue life: fatigue life increased by 2.34 times and 2.56 times after one and two LSP impacts, respectively, compared to the untreated state. As impact cycles increased, the microhardness of the material surface rose by 8.51% and 14.53%, respectively, with residual compressive stresses reaching \u2212145 MPa and \u2212183 MPa. Concurrently, LSP-2 treatment formed a refined microstructure featuring coexisting lamellar \u03b1 and acicular martensite in the surface layer. This strengthening effect is attributed to LSP-induced surface residual compressive stress, grain refinement, and the resulting migration of fatigue crack initiation from the surface to subsurface regions. These findings provide critical insights for optimizing fatigue-resistant designs of additively manufactured titanium alloy components.<\/jats:p>","DOI":"10.3390\/ma18245670","type":"journal-article","created":{"date-parts":[[2025,12,17]],"date-time":"2025-12-17T15:53:46Z","timestamp":1765986826000},"page":"5670","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Effect of Laser Shock Peening Times on Low-Cycle Fatigue Properties and Fracture Mechanism of Additive TA15 Titanium Alloy"],"prefix":"10.3390","volume":"18","author":[{"given":"Xu","family":"Pei","sequence":"first","affiliation":[{"name":"Faculty of Mechanical and Material Engineering, Huaiyin Institute of Technology, Huai\u2019an 223003, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sailan","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering, Jiangsu University, Zhenjiang 212013, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhaomei","family":"Xu","sequence":"additional","affiliation":[{"name":"Faculty of Mechanical and Material Engineering, Huaiyin Institute of Technology, Huai\u2019an 223003, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhouzhi","family":"Gu","sequence":"additional","affiliation":[{"name":"Faculty of Mechanical and Material Engineering, Huaiyin Institute of Technology, Huai\u2019an 223003, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuchun","family":"Peng","sequence":"additional","affiliation":[{"name":"Department of Smart Agriculture and Engineering, Wenzhou Vocational College of Science and Technology, Wenzhou 325006, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4397-0691","authenticated-orcid":false,"given":"Pengfei","family":"Li","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering, Jiangsu University, Zhenjiang 212013, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,12,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1804","DOI":"10.1007\/s11837-021-04670-6","article-title":"A Review on Additive Manufacturing of Titanium Alloys for Aerospace Applications: Directed Energy Deposition and Beyond Ti-6Al-4V","volume":"73","author":"Liu","year":"2021","journal-title":"J. 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