Low temperature superplastic-like deformation and fracture behavior of nano/ultrafine-grained metastable austenitic stainless steel
Abstract We describe here the low temperature superplastic-like deformation in a nano/ultrafine-grained metasable austenitic stainless steel tensile tested at a strain rate of 2.5×10 −4 s −1 and temperature of 600°C (~0.43 of the absolute melting point). The nano/ultrafine-grained structure was obtained via a combination of cold rolling (~93% in reduction), followed by reversion annealing treatments at 650°C for 10min, 30min, and 700°C for 2min, 5min, respectively, an approach previously adopted by Misra's group (references 11–16). The reversion of martensite to austenite was dominated by diffusional mechanism. The nano/ultrafine-grained steel exhibited superplastic-like behavior with maximum elongation approaching ~153% and strain rate sensitivity of ~0.22. Furthermore, tensile deformation behavior at 20°C and 600°C, and the corresponding fracture characteristics are discussed. Observations of fracture surface indicated that the fracture was characterized by line-up of voids along the striations, when tensile tested at 20°C. Whereas, the fracture surface at 600°C mainly consisted of uniform distribution of dimples. To further study the fracture mechanism during superplastic-like deformation, deformed structures from the longitudinal region close to the tip of the fracture surface were studied. The fracture surface of superplastic-like deformed steel was characterized by interlinkage of cavities. Highlights Nano/ultrafine-grained austenitic stainless steel with average grain size of ~150–300nm was obtained. Superplastic-like behavior of nano/ultrafine-grained austenitic stainless steel was observed at a 600°C (~0.43Tm). Fracture behavior during superplastic-like deformation was attributed to be controlled by interlinkage of cavities. Graphical abstract [DISPLAY OMISSION]
유료 다운로드의 경우 해당 사이트의 정책에 따라 신규 회원가입, 로그인, 유료 구매 등이 필요할 수 있습니다. 해당 사이트에서 발생하는 귀하의 모든 정보활동은 NDSL의 서비스 정책과 무관합니다.
원문복사신청을 하시면, 일부 해외 인쇄학술지의 경우 외국학술지지원센터(FRIC)에서
무료 원문복사 서비스를 제공합니다.
NDSL에서는 해당 원문을 복사서비스하고 있습니다. 위의 원문복사신청 또는 장바구니 담기를 통하여 원문복사서비스 이용이 가능합니다.
- 이 논문과 함께 출판된 논문 + 더보기