Transformation-induced plasticity high-entropy alloy and preparation method thereof

Patent metadata

Field	Value
Publication number	US-11313018-B2
Application number	US-201816310545-A
Country	US
Kind code	B2
Filing date	Mar 30, 2018
Priority date	Jul 18, 2017
Publication date	Apr 26, 2022
Grant date	Apr 26, 2022

Abstract

Present invention is about a transformation-induced plasticity high-entropy alloy which can provide improved mechanical properties compared to those obtained by conventional methods, due to the phase transformation occurring at the time of deformation at a cryogenic temperature. According to the present invention, the high-entropy alloy (HEA) includes 10-35 at % of Co, 3-15 at % of Cr, 3-15 at % of V, 35-48 at % of Fe, and 0-25 at % of Ni (exclusive of 25), and mainly consists of an FCC phase at room temperature, wherein transformation-induced plasticity, in which at least part of the FCC phase changes to a BCC phase, occurs at a cryogenic temperature (−196° C.)

First claim

The invention claimed is:

1. A transformation-induced plasticity high-entropy alloy, consisting of 10-35 at % of Co, 3-15 at % of Cr, 3-15 at % of V, 35-48 at % of Fe, and 0-25 at % of Ni (exclusive of 25),
wherein the transformation-induced plasticity high-entropy alloy has an FCC phase in which a fraction is 95% or more at room temperature, and
wherein transformation-induced plasticity, in which at least part of the FCC phase changes to a BCC phase, occurs at a cryogenic temperature (−196° C.).

2. The transformation-induced plasticity high-entropy alloy of claim 1 , wherein a Co content is in a range of 15-30 at %.

3. The transformation-induced plasticity high-entropy alloy of claim 1 , wherein a Cr content is in a range of 5-10 at %.

4. The transformation-induced plasticity high-entropy alloy of claim 1 , wherein a V content is in a range of 5-10 at %.

5. The transformation-induced plasticity high-entropy alloy of claim 1 , wherein the Ni content is in a range of 2.5-20 at %.

6. The transformation-induced plasticity high-entropy alloy of claim 1 , wherein a Fe content is in a range of 40-45 at %.

7. The transformation-induced plasticity high-entropy alloy according to claim 1 , wherein the high-entropy alloy has a tensile strength of 650 MPa or greater and has elongation of 50% or greater, at room temperature (25° C.).

8. The transformation-induced plasticity high-entropy alloy according to claim 1 , wherein the high-entropy alloy has a tensile strength of 1,100 MPa or greater and has an elongation of 65% or greater, at a cryogenic temperature (−196° C.).

9. The transformation-induced plasticity high-entropy alloy according to claim 1 , wherein the high-entropy alloy has a difference in impact energy of 10% or less between room temperature and cryogenic temperature.

Assignees

• Postech Academy—Industry Found
• Postech Acad Ind Found

Inventors

• Lee Byeong-Joo
• Lee Sung-Hak
• Sohn Seok-Su
• Kim Hyoung-Seop
• Kim Dong-Geun
• Jo Yong-Hee
• Choi Won-Mi

Classifications

• C21D8/02

  during manufacturing of plates or strips (C21D8/12 takes precedence) · CPC title

• C22C38/46

  with vanadium · CPC title

• C22C30/00 Primary

  Alloys containing less than 50% by weight of each constituent · CPC title

• C21D8/0273

  Final recrystallisation annealing · CPC title

• C21D6/004

  containing Cr and Ni · CPC title