{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T03:09:32Z","timestamp":1788318572603,"version":"build-2803163510"},"reference-count":25,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2024,3,24]],"date-time":"2024-03-24T00:00:00Z","timestamp":1711238400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"University of Washington"},{"name":"Boeing Company"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Surface residual stresses in welded specimens significantly influence properties such as fatigue resistance, fracture toughness, and the superplasticity of joints. In this study, we employed friction stir welding, a well-established joining method, to weld dissimilar titanium alloys. By combining two distinct titanium alloys, we aimed to harness their unique properties when subjected to cyclic loading, impact, or superplastic forming processes. Utilizing X-ray diffraction, macroscopic surface stresses were assessed in dissimilar titanium alloys (Ti-6242 standard grain (SG) and Ti-54M) welded via friction stir welding, assuming a linear lattice distortion. The study accounted for misalignment, significant distortion, and grain refinement in the stir zone. Macroscopic surface residual stresses were quantified on the weld surface and at a depth of 1.5 mm beneath it within a square cross-section (1 \u00d7 1 mm2) by oscillating the specimen in the (X-Y) direction. The sin2\u03c6 method, implemented through the LEPTOS\u00ae (v7.8) software, was employed for residual stress measurement. The analysis of the results was conducted with respect to different rotation and traverse speeds. It was noted that at the center (CEN) of the weld, commonly referred to as the weld nugget, approximately 50 MPa of tensile stress was observed under the lowest values of both tool rotation speed and traverse speed. Tensile residual stresses were evident at the boundaries and within the stir zone. No discernible pattern was observed at the specified locations. Notably, the resultant values of residual stress, influenced by rotation and traverse speeds, exhibited asymmetry.<\/jats:p>","DOI":"10.3390\/ma17071482","type":"journal-article","created":{"date-parts":[[2024,3,25]],"date-time":"2024-03-25T12:28:06Z","timestamp":1711369686000},"page":"1482","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["Residual Stress Measurement Using X-ray Diffraction in Friction Stir-Welded Dissimilar Titanium Alloys"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6269-5923","authenticated-orcid":false,"given":"Kapil","family":"Gangwar","sequence":"first","affiliation":[{"name":"Mechanical Engineering, School of Engineering, Wentworth Institute of Technology, Boston, MA 02115, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0080-161X","authenticated-orcid":false,"given":"M.","family":"Ramulu","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, University of Washington, Seattle, WA 98115, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,3,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Gangwar, K., Ramulu, M., Cantrell, A., and Sanders, D.G. (2016). Microstructure and Mechanical Properties of Friction Stir Welded Dissimilar Titanium Alloys: TIMET-54M and ATI-425. Metals, 6.","DOI":"10.3390\/met6100252"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Gangwar, K., Mamidala, R., and Sanders, D.G. (2017). Friction Stir Welding of near \u03b1 and \u03b1 + \u03b2 Titanium Alloys: Metallurgical and Mechanical Characterization. Metals, 7.","DOI":"10.3390\/met7120565"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"031006","DOI":"10.1115\/1.4001302","article-title":"Identification of process parameters for friction stir welding Ti-6Al-4V","volume":"132","author":"Edwards","year":"2010","journal-title":"J. Eng. Mater. Technol. Trans. ASME"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"230","DOI":"10.1016\/j.matdes.2017.12.033","article-title":"Friction stir welding of titanium alloys: A review","volume":"141","author":"Gangwar","year":"2018","journal-title":"Mater. 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Process."}],"container-title":["Materials"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1996-1944\/17\/7\/1482\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T14:17:56Z","timestamp":1760105876000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1996-1944\/17\/7\/1482"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,3,24]]},"references-count":25,"journal-issue":{"issue":"7","published-online":{"date-parts":[[2024,4]]}},"alternative-id":["ma17071482"],"URL":"https:\/\/doi.org\/10.3390\/ma17071482","relation":{},"ISSN":["1996-1944"],"issn-type":[{"value":"1996-1944","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,3,24]]}}}