|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Deformation and Damage Mechanisms in High Temperature Ni, Co and Fe-based Superalloys
||Effects of Cr on High-temperature Tensile Properties in High-Ni-containing Austenitic Cast Steels
||Jisung Yoo, Won-Mi Choi, Byeong-Joo Lee, Yong-Jun Oh, Seongsik Jang, Sunghak Lee
|On-Site Speaker (Planned)
20-wt%-Ni-containing austenitic cast steel (N20 steel) has been suggested as a promising candidate steel because turbo-chargers require excellent high-temperature properties at exhaust gas temperatures up to 1050 °C. In this study, austenitic cast steels were newly fabricated by replacing 6 wt% of expensive Ni by 6.9 wt% of inexpensive Mn and by controlling 2~4 wt% of Cr to improve high-temperature tensile properties. The 14-wt%-Ni-containing steel (N14 steel) showed more excellent high-temperature tensile properties than those of the N20 steel without the formation of ferrite, which indicated the successful replacement Ni by Mn, together with cost reduction (~10%) of alloying elements. A small amount of Cr reduction also favorably affected high-temperature properties because the hardness of austenitic matrix was enhanced by fine M23C6 carbides dissolved from M7C3 carbides. Considering both tensile properties and alloying costs, thus, these Cr-controlled N14 steels would be fully used for high-performance turbo-charger applications.
||Planned: Supplemental Proceedings volume