金属热处理 ›› 2024, Vol. 49 ›› Issue (9): 47-50.DOI: 10.13251/j.issn.0254-6051.2024.09.008

• 组织与性能 • 上一篇    下一篇

不同等温温度下P92钢的组织演变

赵勇桃1, 吴银虎1, 鲁海涛2, 王瑞1, 雷丙旺2   

  1. 1.内蒙古科技大学 材料科学与工程学院, 内蒙古 包头 014010;
    2.内蒙古北方重工业集团有限公司, 内蒙古 包头 014030
  • 收稿日期:2024-01-05 修回日期:2024-07-09 出版日期:2024-09-25 发布日期:2024-10-29
  • 作者简介:赵勇桃(1974—),女,教授,博士,主要研究方向为金属材料的组织转变及热加工工艺,E-mail: zyt0011@126.com
  • 基金资助:
    内蒙古科技大学重大横向课题(0904051709)

Microstructure evolution of P92 steel at different isothermal temperatures

Zhao Yongtao1, Wu Yinhu1, Lu Haitao2, Wang Rui1, Lei Bingwang2   

  1. 1. School of Materials Science and Engineering, Inner Mongolia University of Science and Technology, Baotou Inner Mongolia 014010, China;
    2. Inner Mongolia North Heavy Industry Group Co., Ltd., Baotou Inner Mongolia 014030, China
  • Received:2024-01-05 Revised:2024-07-09 Online:2024-09-25 Published:2024-10-29

摘要: 采用膨胀法,测定了P92钢的组织转变温度,并将其奥氏体化后实施不同温度和时间的等温处理。通过OM和SEM表征分析了不同等温温度、不同时间下P92钢的组织演变规律,并利用维氏硬度计测定其硬度。结果表明,P92钢在370 ℃及以下等温1 h时,会发生马氏体转变,室温组织为马氏体;在400~430 ℃等温1 h时,会发生贝氏体转变;在520~620 ℃等温1 h时,过冷奥氏体相对稳定,在短时间内不发生转变。在650 ℃及以上等温足够长时间时(25 h),过冷奥氏体将发生共析分解,形成类珠光体组织;在680~770 ℃等温25 h时,会有先共析铁素体析出,且随着等温温度的升高,先共析相增多。随着等温温度的升高(160~770 ℃),P92钢硬度整体呈下降趋势,由516 HV降低至163 HV。

关键词: P92钢, 等温温度, 组织演变, 硬度

Abstract: Microstructure transition temperatures of the P92 steel were determined by expansion method. After austenitizing, the steel was isothermal treated at different temperatures for different time. Microstructure evolution of the P92 steel isothermal treated at different temperatures for different time was analyzed by OM and SEM. Microhardness of the P92 steel under different states was measured by Vickers hardness tester. The results show that martensite transformation occurs at isothermal temperature of 370 ℃ and below for 1 h, and microstructure of the P92 steel at room temperature is martensitic. Bainite transformation occurs at isothermal temperature of 400-430 ℃ for 1 h. When isothermal treated at 520-620 ℃ for 1 h, the supercooled austenite is relatively stable and doesn't change in a short time. When isothermal treated at 650 ℃ and above for a long time (25 h), eutectoid decomposition of supercooled austenite occur, forming pearlitic structure. When isothermal treated at 680-770 ℃ for 25 h, there is proeutectoid ferrite precipitation, and with the increase of temperature, the proeutectoid phase increases. With the increase of isothermal temperature(160-770 ℃), the hardness of the P92 steel shows an overall downward trend, and gradually decreases from 516 HV to 163 HV.

Key words: P92 steel, isothermal temperature, microstructure evolution, hardness

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