{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T18:08:42Z","timestamp":1789495722603,"version":"build-2803163510"},"reference-count":22,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2021,6,7]],"date-time":"2021-06-07T00:00:00Z","timestamp":1623024000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001691","name":"Japan Society for the Promotion of Science","doi-asserted-by":"publisher","award":["KAKENHI JP19H02417"],"award-info":[{"award-number":["KAKENHI JP19H02417"]}],"id":[{"id":"10.13039\/501100001691","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001691","name":"Japan Society for the Promotion of Science","doi-asserted-by":"publisher","award":["KAKENHI 20K20544"],"award-info":[{"award-number":["KAKENHI 20K20544"]}],"id":[{"id":"10.13039\/501100001691","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>To enhance the mechanical properties (e.g., strength and elongation) of the face-centered cubic (fcc) \u03b1-phase in the Au-Cu-Al system, this study focused on the introduction of the martensite phase (doubled B19 (DB19) crystal structure of Au2CuAl) via the manipulation of alloy compositions. Fundamental evaluations, such as microstructure observations, phase identifications, thermal analysis, tensile behavior examinations, and reflectance analysis, have been conducted. The presence of fcc annealing twins was observed in both the optical microscope (OM) and the scanning electron microscope (SEM) images. Both strength and elongation of the alloys were greatly promoted while the DB19 martensite phase was introduced into the alloys. Amongst all the prepared specimens, the 47Au41Cu12Al and the 44Au44Cu12Al alloys performed the optimized mechanical properties. The enhancement of strength and ductility in these two alloys was achieved while the stress plateau was observed during the tensile deformation. A plot of the ultimate tensile strength (UTS) against fracture strain was constructed to illustrate the effects of the introduction of the DB19 martensite phase on the mechanical properties of the alloys. Regardless of the manipulation of the alloy compositions and the introduction of the DB19 martensite phase, the reflectance stayed almost identical to pure Au.<\/jats:p>","DOI":"10.3390\/ma14113122","type":"journal-article","created":{"date-parts":[[2021,6,7]],"date-time":"2021-06-07T13:25:43Z","timestamp":1623072343000},"page":"3122","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Mechanical Properties Enhancement of the Au-Cu-Al Alloys via Phase Constitution Manipulation"],"prefix":"10.3390","volume":"14","author":[{"given":"Kang-Wei","family":"Goo","sequence":"first","affiliation":[{"name":"Institute of Innovative Research (IIR), Tokyo Institute of Technology, 4259 Nagatsuta, Midori\u2013ku, Yokohama 226\u20138503, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wan-Ting","family":"Chiu","sequence":"additional","affiliation":[{"name":"Institute of Innovative Research (IIR), Tokyo Institute of Technology, 4259 Nagatsuta, Midori\u2013ku, Yokohama 226\u20138503, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7594-2495","authenticated-orcid":false,"given":"Ayano","family":"Toriyabe","sequence":"additional","affiliation":[{"name":"Institute of Innovative Research (IIR), Tokyo Institute of Technology, 4259 Nagatsuta, Midori\u2013ku, Yokohama 226\u20138503, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Masahiro","family":"Homma","sequence":"additional","affiliation":[{"name":"School of Materials and Chemical Technology, Tokyo Institute of Technology, 4259 Nagatsuta, Midori\u2013ku, Yokohama 226\u20138503, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Akira","family":"Umise","sequence":"additional","affiliation":[{"name":"Institute of Innovative Research (IIR), Tokyo Institute of Technology, 4259 Nagatsuta, Midori\u2013ku, Yokohama 226\u20138503, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Masaki","family":"Tahara","sequence":"additional","affiliation":[{"name":"Institute of Innovative Research (IIR), Tokyo Institute of Technology, 4259 Nagatsuta, Midori\u2013ku, Yokohama 226\u20138503, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kenji","family":"Goto","sequence":"additional","affiliation":[{"name":"TANAKA Kikinzoku Kogyo K.K., 28 Suzukawa, Isehara 259\u20131146, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7079-2937","authenticated-orcid":false,"given":"Takumi","family":"Sannomiya","sequence":"additional","affiliation":[{"name":"School of Materials and Chemical Technology, Tokyo Institute of Technology, 4259 Nagatsuta, Midori\u2013ku, Yokohama 226\u20138503, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2794-8988","authenticated-orcid":false,"given":"Hideki","family":"Hosoda","sequence":"additional","affiliation":[{"name":"Institute of Innovative Research (IIR), Tokyo Institute of Technology, 4259 Nagatsuta, Midori\u2013ku, Yokohama 226\u20138503, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"16","DOI":"10.1016\/0160-9327(95)98889-N","article-title":"Spangold: A New Aura for Intermetallics","volume":"19","author":"Wolff","year":"1995","journal-title":"Endeavour"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"44","DOI":"10.1007\/BF03214729","article-title":"The Development of Spangold","volume":"27","author":"Wolff","year":"1994","journal-title":"Gold Bull."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"4167","DOI":"10.1021\/cm8008418","article-title":"Size and Concentration Effect of Gold Nanoparticles on X-Ray Attenuation as Measured on Computed Tomography","volume":"20","author":"Xu","year":"2008","journal-title":"Chem. 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