金属热处理 ›› 2020, Vol. 45 ›› Issue (2): 42-45.DOI: 10.13251/j.issn.0254-6051.2020.02.008

• 组织与性能 • 上一篇    下一篇

DP980高强钢连续退火后的组织与性能

刘靖宝, 张洪波, 耿志宇, 魏焕君   

  1. 河钢集团唐钢公司 技术中心, 河北 唐山 063001
  • 收稿日期:2019-10-08 出版日期:2020-02-25 发布日期:2020-04-03
  • 作者简介:刘靖宝(1983—),男,高级工程师,博士,主要从事汽车、家电板研发与生产,联系电话:0315-2702361,E-mail:liu_jing_bao@163.com。
  • 基金资助:

    河北省重点研发计划(18211014D)

Microstructure and properties of continuous annealed DP980 high strength steel

Liu Jingbao, Zhang Hongbo, Geng Zhiyu, Wei Huanjun   

  1. Technical Center, Hesteel Group Tangsteel Company, Tangshan Hebei 063001, China
  • Received:2019-10-08 Online:2020-02-25 Published:2020-04-03

摘要:

研究了不同工艺参数对980 MPa级连续退火双相钢组织及力学性能的影响,利用光学显微镜、透射电镜(TEM)以及拉伸试验对双相钢的微观组织和力学性能进行测试及分析。结果表明:DP980钢的退火组织主要由铁素体、马氏体岛和少量的贝氏体组成,马氏体岛附近的位错密度较高。随着均热温度的升高,DP980钢的抗拉强度呈现先降低后升高的趋势,屈服强度与抗拉强度的趋势一致,伸长率先升高后降低。随着过时效温度的升高,DP980钢的抗拉强度和屈服强度降低,降低幅度较小,伸长率上升,但变化不明显,说明通过调整过时效温度来调控其力学性能的作用较小。

关键词: 连续退火, 双相钢, 回火, 显微组织, 马氏体岛

Abstract:

Effect of different technological parameters on the microstructure and mechanical properties of continuous annealed DP980 steel (a 980 MPa grade dual-phase steel) were investigated, with the microstructure and mechanical properties being tested and analyzed by means of optical microscopy, TEM and tensile test. The results show that the microstructure of the annealed DP980 steel is mainly composed of ferrite, martensitic islands and a small amount of bainite, and the dislocation density near the martensite island is higher. With the increase of the over aging temperatures, the tensile strength and yield strength of the DP980 steel first decrease and then increase, and the elongation first increases and then decreases. With the increase of the tempering temperature, the tensile strength and yield strength of the DP980 steel decrease within a small range, while the elongation increases but not obvious, which indicates that adjusting the over aging temperature to regulate the mechanical properties is less effective.

Key words: continuous annealing, dual phase steel, over aging, microstructure, martensite island

中图分类号: