Effect of Varying Heat Treatment Regimes on Microstructure and Mechanical Properties of P92 Steel Welds

DOI https://doi.org/10.15407/pmach2022.02.038
Journal Journal of Mechanical Engineering – Problemy Mashynobuduvannia
Publisher A. Pidhornyi Institute for Mechanical Engineering Problems
National Academy of Science of Ukraine
ISSN  2709-2984 (Print), 2709-2992 (Online)
Issue Vol. 25, no. 2, 2022 (June)
Pages 38-59
Cited by J. of Mech. Eng., 2022, vol. 25, no. 2, pp. 38-59



Vinay Kumar Pal, Department of Mechanical Engineering, Sam Higginbottom University of Agriculture, Technology and Sciences (Allahabad, 211 007, Uttar Pradesh, India), e-mail: gaurishankar.vinaypal@gmail.com, ORCID: 0000-0001-7830-570X

Lokendra Pal Singh, Department of Mechanical Engineering, Sam Higginbottom University of Agriculture, Technology and Sciences (Allahabad, 211 007, Uttar Pradesh, India), e-mail: ORCID: 0000-0002-6221-8174



Cr-Mo steels are well-known for their high temperature application in thermal power plants. P91, P911 and P92 are most commonly used Cr-Mo steels for high temperature application. The steels de-rived their strength from tempered martensite and precipitates of MX and M23C6 type. The normalizing and tempering of the steels are performed before putting them in service condition. The present manuscript describes the effect of the varying heat treatment regimes on microstructure and mechanical properties of the P92 steel. The normalizing effect on microstructure and mechanical properties has been studied. The normalizing was performed in the range of 950–1150 ºC. The effect of the varying tempering time on mechanical behavior of the P92 steel has also been studied and effort to develop relation between microstructure and mechanical properties was made. Optical microscope and scanning electron microscope have been utilized for microstructure study. To characterize the mechanical behavior, tensile, hardness and Charpy impact toughness tests were performed.


Keywords: P92, microstructure, mechanical properties, normalizing, tempering.


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Received 05 May 2022

Published 30 March 2022