{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,30]],"date-time":"2026-04-30T02:28:30Z","timestamp":1777516110161,"version":"3.51.4"},"reference-count":68,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2020,12,23]],"date-time":"2020-12-23T00:00:00Z","timestamp":1608681600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>This paper presents the microstructural characteristics and mechanical properties of linear friction-welded (LFWed) Ti-6Al-2Sn-4Zr-2Mo-0.1Si (Ti-6242) in as-welded (AWed) and stress relief-annealed (SRAed) conditions. The weld center (WC) of the AWed Ti-6242 consisted of recrystallized prior-\u03b2 grains with \u03b1\u2019 martensite that were tempered during SRA at 800 \u00b0C for 2 h and transformed into an acicular \u03b1 + \u03b2 microstructure. The peak hardness values, obtained in the AWed joints at the WC, sharply decreased through the thermomechanically affected zones (TMAZs) to the heat-affected zone (HAZ) of the Ti-6242 parent metal (PM). The SRA lowered the peak hardness values at the WC slightly and fully recovered the observed softening in the HAZ. The tensile mechanical properties of the welds in the AWed and SRAed conditions surpassed the minimum requirements in the AMS specifications for the Ti-6242 alloy. Fatigue tests, performed on the SRAed welds, indicated a fatigue limit of 468 MPa at 107 cycles, just slightly higher than that of the Ti-6242 PM (434 MPa). During tensile and fatigue testing, the welds failed in the PM region, which confirms the high mechanical integrity of the joints. Both the tensile and fatigue fracture surfaces exhibited characteristic features of ductile Ti-6242 PM.<\/jats:p>","DOI":"10.3390\/ma14010030","type":"journal-article","created":{"date-parts":[[2020,12,23]],"date-time":"2020-12-23T08:38:43Z","timestamp":1608712723000},"page":"30","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Microstructure, Tensile Properties, and Fatigue Behavior of Linear Friction-Welded Ti-6Al-2Sn-4Zr-2Mo-0.1Si"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9066-2419","authenticated-orcid":false,"given":"Sidharth","family":"Rajan","sequence":"first","affiliation":[{"name":"National Research Council Canada (NRC), Montr\u00e9al, QC H3T 1J4, Canada"},{"name":"Mechanical and Aerospace Department, Carleton University, Ottawa, ON K1S 5B6, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7662-984X","authenticated-orcid":false,"given":"Priti","family":"Wanjara","sequence":"additional","affiliation":[{"name":"National Research Council Canada (NRC), Montr\u00e9al, QC H3T 1J4, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Javad","family":"Gholipour","sequence":"additional","affiliation":[{"name":"National Research Council Canada (NRC), Montr\u00e9al, QC H3T 1J4, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Abu Syed","family":"Kabir","sequence":"additional","affiliation":[{"name":"Mechanical and Aerospace Department, Carleton University, Ottawa, ON K1S 5B6, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,12,23]]},"reference":[{"key":"ref_1","unstructured":"Collins, E.W., Boyer, R., and Welsch, G. 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