金属热处理 ›› 2023, Vol. 48 ›› Issue (2): 67-73.DOI: 10.13251/j.issn.0254-6051.2023.02.011

• 组织与性能 • 上一篇    下一篇

Fe-8Mn-xAl-0.2C冷轧中锰钢的组织与性能

张振伟1, 景颂扬1, 张金城1, 赵文柱2, 丁桦1,3   

  1. 1.东北大学 材料科学与工程学院, 辽宁 沈阳 110819;
    2.东北大学 轧制技术及连轧自动化国家重点实验室, 辽宁 沈阳 110819;
    3.辽宁省轻量化用关键金属材料重点实验室, 辽宁 沈阳 110819
  • 收稿日期:2022-09-20 修回日期:2023-01-07 出版日期:2023-02-25 发布日期:2023-03-22
  • 通讯作者: 丁 桦,教授,博士生导师,E-mail:dingh@smm.neu.edu.cn
  • 作者简介:张振伟(1987—),男,硕士,主要研究方向为材料成形及组织性能控制,E-mail:13889361473@163.com。

Microstructure and mechanical properties of cold-rolled Fe-8Mn-xAl-0.2C medium Mn steel

Zhang Zhenwei1, Jing Songyang1, Zhang Jincheng1, Zhao Wenzhu2, Ding Hua1,3   

  1. 1. School of Materials Science and Engineering, Northeastern University, Shenyang Liaoning 110819, China;
    2. State Key Laboratory of Rolling and Automation, Northeastern University, Shenyang Liaoning 110819, China;
    3. Key Laboratory of Lightweight Structural Materials in Liaoning Province, Shenyang Liaoning 110819, China
  • Received:2022-09-20 Revised:2023-01-07 Online:2023-02-25 Published:2023-03-22

摘要: 利用场发射扫描电镜、电子背散射衍射技术、X射线衍射仪及电子万能试验机等对Fe-8Mn-xAl-0.2C(x=0, 3)冷轧中锰钢的微观组织与性能进行了研究。结果表明,Al的添加使奥氏体化温度明显升高。经高温临界区退火后得到了等轴的奥氏体与铁素体双相组织。添加Al提高了奥氏体的稳定性,影响了试验钢变形过程中的应变硬化行为,材料塑性得到改善。Fe-8Mn-0.2C冷轧试验钢在625 ℃退火获得了最优综合力学性能,抗拉强度为1220 MPa,伸长率为44%,强塑积为54 GPa·%;Fe-8Mn-3Al-0.2C冷轧试验钢在710 ℃退火获得了最优综合力学性能,抗拉强度为970 MPa,伸长率为58%,强塑积为56 GPa·%。此外,Al的添加扩大了试验钢获得优异力学性能的退火温度范围。

关键词: 中锰钢, Al含量, 临界区退火, 奥氏体稳定性, TRIP效应

Abstract: Microstructure and mechanical properties of Fe-8Mn-xAl-0.2C(x=0, 3) cold-rolled medium Mn steel were studied by means of field emission scanning electron microscope, electron backscatter diffraction technology, X-ray diffractometer and electronic universal testing machine. The results show that the addition of Al increases the austenitizing temperature significantly, and the equiaxed austenite and ferrite dual-phase structures are obtained after annealing at higher intercritical annealing temperature. The stability of austenite is improved, which affects the strain hardening behavior of the tested steel during deformation, and the ductility of the steel is improved. When the Fe-8Mn-0.2C cold-rolled tested steel is annealed at 625 ℃, a good combination of strength and ductility is obtained with ultimate tensile strength (UTS) of 1220 MPa, tensile elongation (TE) of 44%, and UTS×TE of 54 GPa·%. But for the Fe-8Mn-3Al-0.2C cold-rolled tested steel, the good combination of strength and ductility is obtained with ultimate tensile strength (UTS) of 970 MPa, tensile elongation (TE) of 58%, UTS×TE of 56 GPa·% when annealed at 710 ℃. Furthermore, the addition of Al widens the intercritical annealing temperature window to attain good mechanical properties.

Key words: medium Mn steel, Al content, intercritical annealing, austenite stability, TRIP effect

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