|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Characterization of Minerals, Metals, and Materials
||LL-71: Microstructure, Mechanical and Oxidation Behavior of Niobium Modified 9% Chromium Steel
||Anup Mandal, Tapas Kumar Bandyopadhay
|On-Site Speaker (Planned)
The effect of tempering on the microstructure of niobium modified 8.8 wt.% chromium steel has been evaluated. Steel has been prepared using conventional melting and casting route. Homogenization and forging is done at 1100˚C. Initial cast and forged microstructures consist of martensite/ferrite. Samples are subsequently tempered at 500-800˚C for various interval of times (1-5 hours). The microstructure of tempered sample is analyzed using optical microscopy, scanning electron microscopy, and x-ray diffraction. High Resolution Transmission Electron Microscopy (HRTEM) is used to identify the precipitate. Nanometer sized precipitates (50-200 nm) are observed after tempering at 700˚C for one hour. Niobium rich MC type carbide precipitate and chromium rich M23C6 type precipitates are observed after tempering at 700˚C. Tensile strength decreases with increasing tempering temperature. Maximum tensile strength of 920 MPa is observed after tempering at 700˚C and maximum elongation of ~11% is observed after tempering at 750˚C.
||Planned: A print-only volume