金属热处理 ›› 2021, Vol. 46 ›› Issue (1): 32-37.DOI: 10.13251/j.issn.0254-6051.2021.01.006

• 工艺研究 • 上一篇    下一篇

回火温度对42CrMo钢组织和力学性能的影响

吕超然1, 史超2, 蒋伟斌3, 刘进德4, 徐乐1, 王毛球1   

  1. 1.钢铁研究总院 特殊钢研究所,北京 100081;
    2.内蒙古北方重工业集团有限公司,内蒙古 包头 014033;
    3.建龙北满特殊钢有限责任公司,黑龙江 齐齐哈尔 161041;
    4.宁夏天地奔牛实业集团有限公司,宁夏 石嘴山 753001
  • 收稿日期:2020-06-12 出版日期:2021-01-25 发布日期:2021-01-26
  • 通讯作者: 徐乐,教授,硕士生导师,E-mail:xule@nercast.com
  • 作者简介:吕超然(1994—),女,硕士研究生,主要研究方向为合金结构钢,E-mail:lvchaoran_cat@163.com。
  • 基金资助:
    国家重点研发计划(2016YFB0300104)

Effect of tempering temperature on microstructure and mechanical properties of 42CrMo steel

Lü Chaoran1, Shi Chao2, Jiang Weibin3, Liu Jinde4, Xu Le1, Wang Maoqiu1   

  1. 1. Central Iron & Steel Research Institute,Beijing 100081,China;
    2. Inner Mongolia North Heavy Industries Group Co.,Ltd.,Baotou Inner Mongolia 014033,China;
    3. Jianlong Beiman Special Steel Co.,Ltd.,Qiqihaer Heilongjiang 161041,China;
    4. Ningxia Tiandi Benniu Industrial Group Co.,Ltd.,Shizuishan Ningxia 753001,China
  • Received:2020-06-12 Online:2021-01-25 Published:2021-01-26

摘要: 通过显微组织观察和力学性能检测,分析了42CrMo钢在不同回火温度下微观组织形貌和力学性能的变化。通过三维原子探针(3DAP)技术分析500 ℃回火温度下42CrMo钢中元素分布情况,研究了Cr、Mn、Mo等合金元素对钢性能的影响。结果表明,42CrMo钢水淬后在450 ℃回火时显微组织为回火屈氏体,在500~650 ℃区间回火时显微组织均为回火索氏体,随着回火温度的增加,颗粒状碳化物增多;抗拉强度和规定塑性延伸强度降低,-40 ℃低温冲击性能升高。在500 ℃回火可达到12.9级螺栓力学指标(Rm≥1200 MPa,KV2≥27 J),力学性能最佳,且满足低温环境下螺栓用钢的使用要求。3DAP结果表明,钢中的合金元素通过固溶强化和沉淀强化提高了钢的性能。

关键词: 42CrMo钢, 回火温度, 力学性能, 微观组织, 三维原子探针(3DAP)

Abstract: Through microstructure observation and mechanical properties test,the changes of microstructure and mechanical properties of 42CrMo steel at different tempering temperatures were analyzed.The distribution of elements in the 42CrMo steel tempered at 500 ℃ was analyzed by 3DAP technology,and the influence of Cr,Mn,Mo,etc.on the steel properties was studied.The results show that the microstructure of the steel is tempered troostite when tempered at 450 ℃ after water quenching.In the tempering range of 500-650 ℃,the microstructure are tempered sorbite.With the increase of tempering temperature,granular carbides increase,the tensile strength and the specified plastic elongation strength decrease,and the -40 ℃ low temperature impact performance increases.Tempering at 500 ℃ can reach the mechanical index of grade 12.9 bolts (Rm≥1200 MPa,KV2≥27 J) and obtain the best mechanical properties,and meet the requirements of bolt steel in low temperature environments.The 3DAP results show that the alloying elements in the steel improve the performance of steel through solid solution strengthening and precipitation strengthening.

Key words: 42CrMo steel, tempering temperature, mechanical properties, microstructure, 3DAP

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