논문 해외 국제전문학술지(SCI급) Tensile properties and microstructure evolution during two-stage tensile testing of CoCrFeMnNi high-entropy alloy
- 학술지 구분 국제전문학술지(SCI급)
- 게재년월 2020-05
- 저자명 김정한,박태성
- 학술지명 JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
- 발행처명 ELSEVIER
- 발행국가 해외
- 논문언어 외국어
- 전체저자수 2
홈페이지논문 초록 (Abstract)
The tensile properties of a CoCrFeMnNi high-entropy alloy, obtained by isothermal tensile testing and two-stage non-isothermal tensile testing, were compared. During the two-stage tensile testing, a tensile sample with the as-cast microstructure was loaded at 22 degrees C up to a strain level of 15%. Subsequently, the tensile specimen was re-loaded until it fractured at 500 degrees C and 700 degrees C. Formation of several steps was observed at the point where grain boundaries and deformation twin boundaries intersect after the two-stage tensile testing at 500 degrees C. The local deformation at the steps results in the fragmentation of the twin lamellae grains, which leads to the formation of an ultra-fine-grain structure. A high density of deformation twins was detected inside the ultra-fine grains. Furthermore, the grain fragmentation mechanism is discussed. (C) 2020 The Author(s). Published by Elsevier B.V.