Microstructure and Mechanical Properties in QT-Treated 9Ni Steel

Abstract:

Microstructure and mechanical properties in QT-Treated 9Ni steel were investigated. The detail microstructures were observed by optical microscope (OM) and transmission electron microscope (TEM). The volume fraction of austenite was estimated by XRD. Tensile test at room temperature and Charpy-V-Notch (CVN) impact test at -196°C were carried out. The results showed that the microstructure of QT-treated 9%Ni steel was composed of tempered martensite and reversed austenite. The brittle cementite was absorbed gradually by the increasing reversed austenite as the tempering temperature increased. The optimum tempering temperature range was 560°C~580°C. The reversed austenite could improve the cryogenic toughness of 9Ni steel through the combination of the scavenging effect and the TRIP effect.

• Periodical: Advanced Materials Research (Volumes 562-564)
• Pages: 39-42
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.562-564.39
• Online since: August 2012
• Authors: Hang Su, Xi Qing Zhao, Tao Pan, Xiao Rong Lei, Qing Feng Wang
• Keywords: 9Ni Steel, Mechanical Property, Microstructure, Reversed Austenite

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