Effect of annealing time on microstructure and mechanical properties of medium carbon steel subcritical quenched

doi:10.13251/j.issn.0254-6051.2023.02.027

Abstract

Abstract: The hot-rolled medium carbon steel was subcritical quenched, then cold rolled(deformation of 50%) and annealed at 550 ℃ for different time. The microstructure of annealed specimens was characterized by means of scanning electron microscopy(SEM), X-ray diffraction (XRD) and backscattered electron diffraction (EBSD), and the effect of bimodal structure on mechanical properties was analyzed by means of tensile experiments at room temperature. The results show that the microstructure after annealing is composed of ferrite and cementite, and the ferrite is composed of fine and coarse crystal regions. With the prolongation of time, the peak value of fine crystal increases slightly, the increase is not obvious, but the peak value of coarse crystal decreases. With the increase of annealing time, the tensile strength and yield strength of the specimens show a decreasing trend, while the elongation shows an increasing trend. The size and depth of dimples increase, and small dimples are enriched near large dimples. When the annealing time is 30 min, the mechanical properties are the best.

Key words: double-peak structure, medium carbon steel, microstructure, mechanical properties

CLC Number:

TG156.1

Li Yaguang, Zhang Jiahao, Li Hongbin, Zhao Zhihao, Xu Haiwei, Tian Yaqiang, Chen Liansheng. Effect of annealing time on microstructure and mechanical properties of medium carbon steel subcritical quenched[J]. Heat Treatment of Metals, 2023, 48(2): 174-179.

References

[1]Sun B H, Ma Y, Vanderesse N, et al. Macroscopic to nanoscopic in situ investigation on yielding mechanisms in ultrafine grained medium Mn steels: Role of the austenite-ferrite interface[J]. Acta Materialia, 2019, 178(7): 10-25.
[2]Souza Filho I R, Sandim M J R, Ponge D, et al. Strain hardening mechanisms during cold rolling of a high-Mn steel: Interplay between submicron defects and microtexture[J]. Materials Science and Engineering A, 2019, 754(29): 636-649.
[3]Lin X P, Dang Y Z, Dai P L, et al. Microstructure control and strengthening mechanism of fine-grained cast Mg alloys based on grain boundary segregation of Al solute[J]. Materials Science and Engineering A, 2022, 851: 143665.
[4]Zhou J H, Shen Y F, Hong Y Y, et al. Strengthening a fine-grained low activation martensitic steel by nanosized carbides[J]. Materials Science and Engineering A, 2020, 769: 138471.
[5]Song R, Ponge D, Raabe D. Improvement of the work hardening rate of ultrafine grained steels through second phase particles[J]. Scripta Materialia, 2005, 52(11): 1075-1080.
[6]谢盼. 含锰 TRIP/TWIP 钢的强韧化研究[D]. 长沙: 湖南大学, 2018.
Xie Pan. Study on strengthening and toughening of TRIP/TWIP Steel containing manganese[D]. Changsha: Hunan University, 2018.
[7]Lu L, You Z S, Lu K. Work hardening of polycrystalline Cu with nanoscale twins[J]. Scripta Materialia, 2012, 66(11): 837-842.
[8]Park H W, Yanagimoto J. Formation process and mechanical properties of 0.2% carbon steel with bimodal microstructures subjected to heavy-reduction single-pass hot/warm compression[J]. Materials Science and Engineering A, 2013, 567: 29-37.
[9]刘俊芳. HDDR-SPS-挤压制备双峰组织镁及微观组织和力学性能分析[D]. 太原: 太原理工大学, 2017.
Liu Junfang. Preparation of bimodal magnesium by HDDR-SPS- extrusion and analysis of microstructure and mechanical properties[D]. Taiyuan: Taiyuan University of Technology, 2017.
[10]Ning J L, Feng Y L, Wang M M, et al. Dependence of tensile properties on microstructural features of bimodal-sized ferrite/cementite steels[J]. Journal of Iron and Steel Research International, 2017, 24(1): 67-76.
[11]田亚强, 黎旺, 郑小平, 等. 合金元素在淬火配分钢中的应用研究进展[J]. 材料导报, 2019, 33(7): 1109-1118.
Tian Yaqiang, Li Wang, Zheng Xiaoping, et al. Application of alloy elements in quenching and partitioning steel: An overview[J]. Materials Reports, 2019, 33(7): 1109-1118.
[12]Liu S T, Ku H Y, Huang C L, et al. Improvements in Li deposition and stripping induced by Cu (111) nanotwinned columnar grains[J]. Electrochimica Acta, 2022, 430: 141011.
[13]Hearn W, Lindgren K, Persson J, et al. In situ tempering of martensite during laser powder bed fusion of Fe-0. 45C steel[J]. Materialia, 2022, 23: 101459.
[14]Ragger K S, Primig S, Daniel R, et al. Cold pilgering of duplex steel tubes: The response of austenite and ferrite to excessive cold deformation up to high strains[J]. Materials Characterization, 2017, 128: 257-268.
[15]Ghorabaei A S, Nili-Ahmadabadi M. Effects of prior austenite grain size and phase transformation temperature on bainitic ferrite formation in multi-constituent microstructures of a strong ultra-low-carbon steel[J]. Materials Science and Engineering A, 2021, 815: 141300.
[16]Li H B, Zheng X P, Wan D C, et al. Effect of time interval on microstructure evolution of medium carbon steel during warm deformation[J]. Journal of Iron and Steel Research International, 2019, 26(6): 602-610.
[17]Kim Y J, Asghari-Rad P, Lee J W, et al. Solid solution induced back-stress in multi-principal element alloys: Experiment and modeling[J]. Materials Science and Engineering A, 2022, 835: 142621.