金属热处理 ›› 2025, Vol. 50 ›› Issue (7): 89-95.DOI: 10.13251/j.issn.0254-6051.2025.07.013

• 组织与性能 • 上一篇    下一篇

预备热处理工艺对4Cr5Mo2NiVCo模具钢显微组织与冲击性能的影响

夏云峰1, 周仲成1, 周世杰1, 雷晓娟2, 刘艳春1   

  1. 1.内蒙古北方重工业集团有限公司 特钢事业部, 内蒙古 包头 014033;
    2.中信重工机械股份有限公司 铸锻分公司, 河南 洛阳 471000
  • 收稿日期:2025-01-13 修回日期:2025-04-25 出版日期:2025-07-25 发布日期:2025-07-28
  • 作者简介:夏云峰(1985—),男,高级工程师,主要研究方向为金属材料热处理,E-mail:haiwen0602@126.com

Effect of pretreatment process on microstructure and impact property of 4Cr5Mo2NiVCo mold steel

Xia Yunfeng1, Zhou Zhongcheng1, Zhou Shijie1, Lei Xiaojuan2, Liu Yanchun1   

  1. 1. Special Steel Division, Inner Mongolia North Heavy Industry Group Co., Ltd., Baotou Inner Mongolia 014033, China;
    2. Casting and Forging Branch, CITIC Heavy Industry Machinery Co., Ltd., Luoyang Henan 471000, China
  • Received:2025-01-13 Revised:2025-04-25 Online:2025-07-25 Published:2025-07-28

摘要: 采用JMatPro模拟计算软件及试验研究相结合的方式,对4Cr5Mo2NiVCo模具钢的预备热处理工艺进行了研究。结果表明,4Cr5Mo2NiVCo钢对奥氏体化加热温度较为敏感,当奥氏体化温度达到1020 ℃时,晶粒开始出现粗化现象,在1020 ℃以上淬火,组织中会出现针状马氏体,对冲击性能产生不利影响。该钢经1020 ℃以下淬火再经750 ℃高温回火的预备热处理,可获得铁素体基体上均匀分布细颗粒状碳化物的粒状珠光体组织。在最终热处理工艺相同的条件下,随着预备热处理的奥氏体化温度的升高,材料的冲击性能逐步下降,硬度先升高后略有下降,在预备热处理的奥氏体化温度为1010 ℃时,硬度达到最高值,同时冲击吸收能量可保持在25 J以上。

关键词: 模具钢, 淬火, 回火, 预处理, 显微组织, 碳化物, 冲击性能

Abstract: Pretreatment process of 4Cr5Mo2NiVCo die steel was studied by using a combination of JMatPro simulation software and experimental research. The results show that the 4Cr5Mo2NiVCo steel is sensitive to the austenitizing heating temperature. When the austenitizing temperature reaches 1020 ℃, the grain size begins to coarsen. After quenching above 1020 ℃, needle-like martensite appears in the microstructure, which has an adverse effect on the impact property. The steel undergoes a pretreatment of quenching below 1020 ℃ and then high-temperature tempering at 750 ℃, resulting in a granular pearlite structure with uniformly distributed fine carbides on the ferrite matrix. Under the same final treatment conditions, as the austenitizing temperature of pretreatment increases, the impact property of the steel gradually decreases, and the hardness first increases and then slightly decreases. When the austenitizing temperature of pretreatment is 1010 ℃, the hardness reaches the highest value, and the impact absorbed energy maintains above 25 J.

Key words: mold steel, quenching, tempering, pretreatment, microstructure, carbide, impact property

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