{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,11]],"date-time":"2026-09-11T04:59:26Z","timestamp":1789102766183,"version":"build-2803163510"},"reference-count":28,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2025,8,11]],"date-time":"2025-08-11T00:00:00Z","timestamp":1754870400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["52205142"],"award-info":[{"award-number":["52205142"]}]},{"name":"National Natural Science Foundation of China","award":["22KJB460012"],"award-info":[{"award-number":["22KJB460012"]}]},{"name":"National Natural Science Foundation of China","award":["KYCX23_3089"],"award-info":[{"award-number":["KYCX23_3089"]}]},{"name":"National Natural Science Foundation of China","award":["YPC23020133"],"award-info":[{"award-number":["YPC23020133"]}]},{"name":"Natural Science Research of Jiangsu Higher Education Institutions of China","award":["52205142"],"award-info":[{"award-number":["52205142"]}]},{"name":"Natural Science Research of Jiangsu Higher Education Institutions of China","award":["22KJB460012"],"award-info":[{"award-number":["22KJB460012"]}]},{"name":"Natural Science Research of Jiangsu Higher Education Institutions of China","award":["KYCX23_3089"],"award-info":[{"award-number":["KYCX23_3089"]}]},{"name":"Natural Science Research of Jiangsu Higher Education Institutions of China","award":["YPC23020133"],"award-info":[{"award-number":["YPC23020133"]}]},{"name":"Postgraduate Research &amp; Practice Innovation Program of Jiangsu Province","award":["52205142"],"award-info":[{"award-number":["52205142"]}]},{"name":"Postgraduate Research &amp; Practice Innovation Program of Jiangsu Province","award":["22KJB460012"],"award-info":[{"award-number":["22KJB460012"]}]},{"name":"Postgraduate Research &amp; Practice Innovation Program of Jiangsu Province","award":["KYCX23_3089"],"award-info":[{"award-number":["KYCX23_3089"]}]},{"name":"Postgraduate Research &amp; Practice Innovation Program of Jiangsu Province","award":["YPC23020133"],"award-info":[{"award-number":["YPC23020133"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>This study investigates premature fatigue failures in three EA1N steel axles from permanent magnet direct-drive locomotives during wheel-seat bending tests. Complete fracture occurred in one axle at 3 million cycles, and in the other two axles, cracks appeared and were observed through magnetic particle detection at 3.5 million and 1.6 million cycles, respectively. A comprehensive failure analysis was conducted through metallurgical examination, fractography, mechanical testing, residual stress measurement, and finite element analysis. The fractographic results revealed fractures consistently initiated at the wheel-seat to axle-body transition arc, exhibiting characteristic ratchet marks and beach patterns. The premature fracture mechanism was identified as a high-stress fatigue fracture. The residual stress measurements showed detrimental tensile stresses at the surface. Coupled with the operating stress, the stress on the axle exceeds fatigue strength, which accelerates the initiation and propagation of fatigue cracks. Based on these observations, the failure mechanism was identified, and preventive methods were proposed to reduce the risk of recurrence of the in-service axles.<\/jats:p>","DOI":"10.3390\/ma18163747","type":"journal-article","created":{"date-parts":[[2025,8,11]],"date-time":"2025-08-11T09:59:13Z","timestamp":1754906353000},"page":"3747","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Premature Fatigue Failure Analysis of Axle in Permanent Magnet Direct-Drive Electric Locomotive"],"prefix":"10.3390","volume":"18","author":[{"given":"An-Xia","family":"Pan","sequence":"first","affiliation":[{"name":"School of Mechanical Engineering and Rail Transit, Changzhou University, Changzhou 213164, China"},{"name":"Jiangsu Key Laboratory of Green Process Equipment, Changzhou University, Changzhou 213164, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-0608-2495","authenticated-orcid":false,"given":"Chao","family":"Wen","sequence":"additional","affiliation":[{"name":"Institute of Materials Modification and Modelling, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China"},{"name":"Shanghai Key Laboratory of Materials Laser Processing and Modification, Shanghai Jiao Tong University, Shanghai 200240, China"},{"name":"CRRC Qishuyan Institute Co., Ltd., Changzhou 213011, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Haoyu","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering and Rail Transit, Changzhou University, Changzhou 213164, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peng","family":"Shi","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering and Rail Transit, Changzhou University, Changzhou 213164, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Quanchang","family":"Bi","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering and Rail Transit, Changzhou University, Changzhou 213164, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xicheng","family":"Jia","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering and Rail Transit, Changzhou University, Changzhou 213164, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1518-3033","authenticated-orcid":false,"given":"Ping","family":"Tao","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering and Rail Transit, Changzhou University, Changzhou 213164, China"},{"name":"Jiangsu Key Laboratory of Green Process Equipment, Changzhou University, Changzhou 213164, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-4582-1839","authenticated-orcid":false,"given":"Xuedong","family":"Liu","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering and Rail Transit, Changzhou University, Changzhou 213164, China"},{"name":"Jiangsu Key Laboratory of Green Process Equipment, Changzhou University, Changzhou 213164, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2199-7797","authenticated-orcid":false,"given":"Yi","family":"Gong","sequence":"additional","affiliation":[{"name":"Department of Materials Science, Fudan University, Shanghai 200433, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhen-Guo","family":"Yang","sequence":"additional","affiliation":[{"name":"Department of Materials Science, Fudan University, Shanghai 200433, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,8,11]]},"reference":[{"key":"ref_1","unstructured":"(2003). 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