金属热处理 ›› 2022, Vol. 47 ›› Issue (9): 158-163.DOI: 10.13251/j.issn.0254-6051.2022.09.028

• 组织与性能 • 上一篇    下一篇

高钼无磁钢等温变形脆化现象及其机理

姜一鸣1,2, 屈华鹏2, 郎宇平2, 冯翰秋2, 陈海涛2, 李向明1   

  1. 1.昆明理工大学 材料科学与工程学院, 云南 昆明 650093;
    2.钢铁研究总院 特殊钢研究院, 北京 100081
  • 收稿日期:2022-04-27 修回日期:2022-07-25 发布日期:2022-10-18
  • 通讯作者: 李向明,教授,博士, E-mail:Lixm@kmust.edu.cn
  • 作者简介:姜一鸣(1997—),男,硕士研究生,主要研究方向为不锈钢及耐蚀合金材料,E-mail:1076010282@qq.com。

Isothermal deformation embrittlement phenomenon and mechanism of high molybdenum non-magnetic steel

Jiang Yiming1,2, Qu Huapeng2, Lang Yuping2, Feng Hanqiu2, Chen Haitao2, Li Xiangming1   

  1. 1. School of Materials Science and Engineering, Kunming University of Science and Technology, Kunming Yunnan 650093, China;
    2. Research Institute of Special Steel, General Iron and Steel Research Institute, Beijing 100081, China
  • Received:2022-04-27 Revised:2022-07-25 Published:2022-10-18

摘要: 采用Thermal-Calc热力学计算软件对高钼无磁钢碳化物析出热力学特征进行了计算。通过光学显微镜、扫描电镜等设备探讨了时效温度、等温变形+时效温度对试验钢析出行为的影响,并进行了冲击试验。结果表明,析出相主要在晶界处产生,试验钢析出敏感温度为700~900 ℃。在800 ℃下时效1 h后,试验钢晶界处可以明显观察到析出相的产生,为颗粒状。与无变形相比,析出相在变形条件下大量形成,形状为条带状,晶界明显变粗,与时效态试样相比,时效前的变形明显缩短了析出相的孕育时间,促进了析出相的长大。等温变形+时效后会显著降低冲击性能,断裂方式为韧性断裂。

关键词: 无磁钢, 等温变形, 析出相, 碳化物

Abstract: Thermodynamic characteristics of carbide precipitation in high molybdenum non-magnetic steel were calculated by using Thermal-Calc thermodynamic calculation software. The effect of aging temperature, isothermal deformation+aging temperature on the precipitation behavior of the tested steel was discussed by means of optical microscope, scanning electron microscope and other equipment, and the impact test was carried out. The results show that the precipitation phase is mainly produced at the grain boundary, and the temperature sensitive to precipitation of the tested steel is 700-900 ℃. After aging at 800 ℃ for 1 h, the formation of precipitates can be clearly observed at the grain boundaries of the tested steel, which are granular. Compared with no deformation, the precipitates are formed in large quantities under deformation conditions, the shape is strip-like, and the grain boundaries are obviously thickened. Compared with the aged specimens, the deformation before aging significantly shortens the incubation time of the precipitates and promotes the growth of the precipitates. After isothermal deformation+aging, the impact performance is significantly reduced, and the fracture mode is ductile fracture.

Key words: non-magnetic steel, isothermal deformation, precipitated phase, carbide

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