Effect of Heat Treatment on Microstructure and Hardness of Grade 91 Steel

Metals

Triratna Shrestha¹  Sultan F. Alsagabi¹  Indrajit Charit¹  Gabriel P. Potirniche²  Michael V. Glazoff³ 

[1] Department of Chemical and Materials Engineering, University of Idaho, Moscow, ID 83844-3024, USA; E-Mails:;Department of Mechanical Engineering, University of Idaho, Moscow, ID 83844-0902, USA; E-Mail:;Energy Systems Integration, Idaho National Laboratory, Idaho Falls, ID 83415-3710, USA

关键词: modified 9Cr-1Mo steel;    Grade 91 steel;    heat treatment;    microstructure;    differential scanning calorimetry;    Thermo-Calc™;    precipitates;   

DOI  :  10.3390/met5010131

来源: mdpi

【 摘 要 】

Grade 91 steel (modified 9Cr-1Mo steel) is considered a prospective material for the Next Generation Nuclear Power Plant for application in reactor pressure vessels at temperatures of up to 650 °C. In this study, heat treatment of Grade 91 steel was performed by normalizing and tempering the steel at various temperatures for different periods of time. Optical microscopy, scanning and transmission electron microscopy in conjunction with microhardness profiles and calorimetric plots were used to understand the microstructural evolution including precipitate structures and were correlated with mechanical behavior of the steel. Thermo-Calc™ calculations were used to support the experimental work. Furthermore, carbon isopleth and temperature dependencies of the volume fraction of different precipitates were constructed.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.