{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T03:41:25Z","timestamp":1788320485146,"version":"build-2803163510"},"reference-count":54,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2023,4,19]],"date-time":"2023-04-19T00:00:00Z","timestamp":1681862400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Higher Education Sprout Project by the Ministry of Education (MOE)","award":["NSTC 111-2634-F-007-008"],"award-info":[{"award-number":["NSTC 111-2634-F-007-008"]}]},{"name":"Higher Education Sprout Project by the Ministry of Education (MOE)","award":["NSTC 111-2224-E-007-003"],"award-info":[{"award-number":["NSTC 111-2224-E-007-003"]}]},{"name":"National Science and Technology Council (NSTC)","award":["NSTC 111-2634-F-007-008"],"award-info":[{"award-number":["NSTC 111-2634-F-007-008"]}]},{"name":"National Science and Technology Council (NSTC)","award":["NSTC 111-2224-E-007-003"],"award-info":[{"award-number":["NSTC 111-2224-E-007-003"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>The major challenge of high-temperature shape memory alloys (SMAs) is the collocation of phase transition temperatures (TTs: Ms, Mf, As, Af) with the mechanical properties required for application. Previous research has shown that the addition of Hf and Zr into NiTi shape memory alloys (SMAs) increases TTs. Modulating the ratio of Hf and Zr can control the phase transformation temperature, and applying thermal treatments can also achieve the same goal. However, the influence of thermal treatments and precipitates on mechanical properties has not been widely discussed in previous studies. In this study, we prepared two different kinds of shape memory alloys and analyzed their phase transformation temperatures after homogenization. Homogenization successfully eliminated dendrites and inter-dendrites in the as-cast states, resulting in a reduction in the phase transformation temperatures. XRD patterns indicated the presence of B2 peaks in the as-homogenized states, demonstrating a decrease in phase transformation temperatures. Mechanical properties, such as elongation and hardness, were improved due to the uniform microstructures achieved after homogenization. Moreover, we discovered that different additions of Hf and Zr resulted in distinct properties. Alloys with lower Hf and Zr had lower phase transformation temperatures, followed by higher fracture stress and elongation.<\/jats:p>","DOI":"10.3390\/ma16083212","type":"journal-article","created":{"date-parts":[[2023,4,20]],"date-time":"2023-04-20T02:01:11Z","timestamp":1681956071000},"page":"3212","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Effect of Homogenization on the Transformation Temperatures and Mechanical Properties of Cu15Ni35Hf12.5Ti25Zr12.5 and Cu15Ni35Hf15Ti20Zr15 High-Entropy Shape Memory Alloys"],"prefix":"10.3390","volume":"16","author":[{"given":"Shu-Yu","family":"Kuo","sequence":"first","affiliation":[{"name":"Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wei-Pin","family":"Kao","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shan-Hsiu","family":"Chang","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ting-En","family":"Shen","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jien-Wei","family":"Yeh","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan"},{"name":"High Entropy Materials Center, National Tsing Hua University, Hsinchu 30013, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3072-7916","authenticated-orcid":false,"given":"Che-Wei","family":"Tsai","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan"},{"name":"High Entropy Materials Center, National Tsing Hua University, Hsinchu 30013, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,4,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"299","DOI":"10.1002\/adem.200300567","article-title":"Nanostructured high-entropy alloys with multiple principal elements: Novel alloy design concepts and outcomes","volume":"6","author":"Yeh","year":"2004","journal-title":"Adv. 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