Effect of high temperature aging on microstructure and hardness of P91 steel

doi:10.13251/j.issn.0254-6051.2022.12.002

Abstract

Abstract: P91 steel was aged at 650 ℃ for 2935 h. The hardness change during aging was measured, and the influence of microstructure change on hardness was analyzed. The results show that in the early aging period, the hardness increases slightly due to the precipitation of M₂₃C₆. During the subsequent aging, M₂₃C₆ is matured and its quantity density decreases, at the same time, the hardness of the P91 steel decreases slowly due to the slow growth of sub crystal and slight decrease of dislocation density. According to the changes of microstructure and hardness during the aging process, it can be predicted that the P91 steel has better stability of microstructure and properties when it is in service at the temperature not exceeding 600 ℃.

Key words: P91 steel, high temperature aging, microstructure, hardness

CLC Number:

TG142.1

Zhang Kai, Wang Xue, Ni Mansheng, Liu Junjian, Du Chengchao. Effect of high temperature aging on microstructure and hardness of P91 steel[J]. Heat Treatment of Metals, 2022, 47(12): 7-12.

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