Microstructure and tensile property of a precipitation strengthened high entropy alloy processed by selective laser melting and post heat treatment

Wei Chih Lin, Yao Jen Chang, Tzu Hou Hsu, Stéphane Gorsse, Fei Sun, Tadashi Furuhara, An Chou Yeh

研究成果: Article査読

39 被引用数 (Scopus)

抄録

The microstructure and tensile property of Al0.2Co1.5CrFeNi1.5Ti0.3 high entropy alloy (HEA) processed by selective laser melting (SLM) have been studied in comparisons to that fabricated by traditional cast & wrought (C&W) route. The C&W samples were annealed and then aged at 750 ℃ for 50 h to promote precipitation strengthening of L12 structured phase in FCC matrix. By contrast, SLM samples were aged directly at 750 ℃ for 50 h from the as-built condition, which possessed sub-micron dendritic segregation, internal stress and nano oxides; the result was a microstructure with not only L12 particles dispersion, but also L21 phase was formed at subgrain boundaries, nano oxides and dislocations were present in the matrix. The tensile properties of this HEA were significantly enhanced by the SLM and direct ageing process; the room temperature yield strength (1235 MPa) and ultimate tensile strength (1550 MPa) achieved in this work are the highest to-date for HEAs subjected to laser additive manufacturing processes. Comparing to those of C&W samples, the SLM samples at room temperature and 500 °C exhibited additional yield strengths of 284 MPa and 229 MPa, and additional ultimate tensile strengths of 240 MPa and 275 MPa, respectively. The degree of L12 phase precipitation strengthening was similar for both SLM and C&W samples subjected to the same ageing treatment, interestingly, the additional microstructure features of SLM sample provided extra strengthening contributions; detailed analysis on microstructure evolution and strengthening factors are presented and discussed in this article.

本文言語English
論文番号101601
ジャーナルAdditive Manufacturing
36
DOI
出版ステータスPublished - 2020 12月

ASJC Scopus subject areas

  • 生体医工学
  • 材料科学(全般)
  • 工学(その他)
  • 産業および生産工学

フィンガープリント

「Microstructure and tensile property of a precipitation strengthened high entropy alloy processed by selective laser melting and post heat treatment」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。

引用スタイル