Effect of Nb addition and heat treatment on microstructure and properties of heterogeneous high carbon steel

doi:10.13251/j.issn.0254-6051.2025.02.021

Abstract

Abstract: High carbon steel Fe-0.86%C-0.04%Nb(mass fraction) was quenched at 1150 ℃ and tempered at different temperatures. The microstructure of the high carbon steel specimens under different heat treatment conditions was characterized by means of OM, SEM and EPMA. The macro and micro hardness tests were carried out by using Vickers hardness tester and nanoindentation tester, respectively, and compared with high carbon steel with the same C content. The effect of Nb on the microstructure and properties of high carbon steel was studied. The results show that the addition of Nb in high carbon steel can slow down the dissipation of C at the surface of specimen during quenching, and change the distribution of C at the core. The microstructure at the surface is martensite and retained austenite, and the microstructure at the core is composed of pearlite, proeutectoid ferrite and a small amount of martensite, and the heterostructure is obtained from the surface to the core. During tempering, Nb promotes the precipitation of fine granular carbides. After tempering at 300 ℃, the microstructure at surface of the high carbon steel specimen containing Nb is tempered martensite, and the microstructure of core is pearlite+ferrite+a small amount of tempered martensite, the Vickers hardness is 506 HV0.2 and 240 HV0.2, respectively, and the nanoindentation hardness of surface martensite and core pearlite is 4.20 GPa and 2.42 GPa, respectively. The surface has higher hardness, and the core has stronger toughness, showing the characteristics of hard surface and tough core.

Key words: Nb microalloying, heterogeneous, high carbon steel, quenching and tempering, hard surface and tough core

CLC Number:

TG142

Zhao Weinan, Lu Chao, Wang Haoyun, Cao Jianchun, Zhang Yongqing, Zhou Xiaolong. Effect of Nb addition and heat treatment on microstructure and properties of heterogeneous high carbon steel[J]. Heat Treatment of Metals, 2025, 50(2): 133-141.

References

[1] Zhu Y T, Wu X L. Heterostructured materials[J]. Progress in Materials Science, 2023, 131: 101019.
[2] Zhu Y T, Ameyam K, Anserson P M, et al. Heterostructured materials: Superior properties from hetero-zone interaction[J]. Materials Research Letters, 2021, 9(1): 1-31.
[3] Sankaran S, Sarma V S, Padmanabhan K A, et al. High cycle fatigue behaviour of a multiphase microalloyed medium carbon steel: A comparison between ferrite-pearlite and tempered martensite microstructures[J]. Materials Science and Engineering A, 2003, 362(1/2): 249-256.
[4] Gladshtein L I, Larionova N P, Belyaev B F. Effect of ferrite-pearlite microstructure on structural steel properties[J]. Metallurgist, 2012, 56(7/8): 579-590.
[5] 王浩云, 曹建春, 阴树标, 等. 铌对高碳钢共析转变和退火组织的影响[J]. 昆明理工大学学报(自然科学版), 2023, 48(2): 21-30, 40.
Wang Haoyun, Cao Jianchun, Yin Shubiao, et al. Effects of niobium on eutectoid transformation and annealing microstructure of high carbon steel[J]. Journal of Kunming University of Science and Technology(Natural Science), 2023, 48(2): 21-30, 40.
[6] Yong Q L, Zhang Z Y, Sun X J,et al. Effect of dissolved niobium on eutectoid transformation behavior[J]. Journal of Iron and Steel Research International, 2017, 24(9): 973-978.
[7] 张正延, 雍岐龙, 孙新军, 等. 共析钢中铌对珠光体相变行为的影响[J]. 钢铁, 2012, 47(4): 79-83.
Zhang Zhengyan, Yong Qilong, Sun Xinjun, et al. Effect of Nb on pearlite transformation behavior of eutectoid steel[J]. Iron and Steel, 2012, 47(4): 79-83.
[8] Zhang C L, Liu Y Z, Zhou L Y, et al. Forming condition and control strategy of ferrite decarburization in 60Si2MnA spring steel wires for automotive suspensions[J]. Journal of Iron and Steel Research International, 2012, 19: 116-121.
[9] 张朝磊, 韩强, 孙帅, 等. Nb-V复合微合金化对60Si2MnA弹簧钢耐腐蚀性能的影响[J]. 金属热处理, 2010, 35(11): 42-44.
Zhang Chaolei, Han Qiang, Sun Shuai, et al. Effects of Nb-V microalloying on corrosion resistance of 60Si2MnA spring steel[J]. Heat Treatment of Metals, 2010, 35(11): 42-44.
[10] 苏雪, 王厚昕, 朱敏, 等. 原位观察铌对高碳钢珠光体相变的影响[J]. 钢铁, 2022, 57(4): 88-96.
Su Xue, Wang Houxin, Zhu Min, et al. In-situ observation for effect of niobium on pearlite transformation in high-carbon steels[J]. Iron and Steel, 2022, 57(4): 88-96.
[11] Liu X, Cao J C, Chen W, et al. Post-rolling cooling phase transformation and microstructure of high-strength anti-seismic rebars with different solute Nb and austenite microstructure[J]. Metals, 2022, 12(10): 1734.
[12] Dey I, Chandra S, Saha R, et al. Effect of Nb micro-alloying on microstructure and properties of thermo-mechanically processed high carbon pearlitic steel[J]. Materials Characterization, 2018, 140: 45-54.
[13] Tian J, Wang H, Zhu M, et al. Improving mechanical properties in high-carbon pearlitic steels by replacing partial V with Nb[J]. Materials Science and Engineering A, 2022, 834: 142622.
[14] 张朝磊, 邵珠浩, 李戬, 等. 铌微合金化技术在中高碳钢中的应用现状与发展[J]. 材料导报, 2021, 35(5): 5102-5106.
Zhang Chaolei, Shao Zhuhao, Li Jian, et al. Application and development of niobium microalloying technology in medium and high carbon steel[J]. Materials Reports, 2021, 35(5): 5102-5106.
[15] Varshney A, Verma D, Sangal S, et al. High strength high carbon low alloy pearlite-ferrite-tempered martensite steels[J]. Transactions of the Indian Institute of Metals, 2015, 68(1): 117-128.
[16] 卢超, 曹建春, 陈伟, 等. 再加热温度对Nb微合金化钢筋连续冷却相变及组织与性能的影响[J]. 材料导报, 2023, 37(8): 146-153.
Lu Chao, Cao Jianchun, Chen Wei, et al. Effect of reheating temperature on continuous cooling transformation, microstructure and properties of Nb microalloyed rebar[J]. Materials Reports, 2023, 37(8): 146-153.
[17] Hulka K, Kern A, Schriever U. Application of niobium in quenched and tempered high-strength steels[J]. Materials Science Forum, 2005, 500-501: 519-526.
[18] Olsen G B, Cohen M. A mechanism for the strain-induced nucleation of martensitic transformations[J]. Journal of Less Common Metals, 1972, 28(1): 107-118.
[19] 周自强. 钢中马氏体的形态转化[J]. 机械, 1981(9): 30-38.
[20] 李翔, 康永林, 顾克进, 等. 铌微合金化高碳钢的连续冷却转变[J]. 钢铁研究学报, 2004, 16(3): 44-48.
Li Xiang, Kang Yonglin, Gu Kejin, et al. Continuous cooling transformation of niobium microalloyed high carbon steels[J]. Journal of Iron and Steel Research, 2004, 16(3): 44-48.
[21] 高丽. 铌在钢中的结构及铌对钢性能影响的第一性原理计算[D]. 包头: 内蒙古科技大学, 2013.
[22] 徐祖耀, 李学敏. 低碳马氏体形成时碳的扩散[J]. 金属学报, 1983, 19(2): 27-28, 83-88.
Xu Zuyao, Li Xuemin. Diffusion of carbon during the formation of low-carbon martensite[J]. Acta Metallurgica Sinica,1983, 19(2): 27-28, 83-88.
[23] 颜睿. 激光熔覆中高碳钢马氏体组织的阶梯回火机理研究[D]. 武汉: 华中科技大学, 2021.
[24] 刘铖霖. 铌对高碳钢正火态和退火态组织的影响[D]. 昆明: 昆明理工大学, 2019.
[25] Gavriljuk V G. Decomposition of cementite in pearlitic steel due to plastic deformation[J]. Materials Science and Engineering A, 2003, 345(1/2): 81-89.
[26] Liu P C, Wang Z X, Cong J H, et al, The significance of Nb interface segregation in governing pearlitic refinement in high carbon steels[J]. Materials Letters, 2020, 279: 128520.
[27] 陈婉芳, 袁晓敏, 陈明华. 低碳微合金钢微观组织的纳米压痕研究[J]. 安徽工业大学学报(自然科学版), 2014, 31(1): 39-42.
Chen Wanfang, Yuan Xiaomin, Chen Minghua. Investigation on the nanoindentation of microstructure in low carbon microalloyed high strength steel[J]. Journal of Anhui University of Technology(Natural Science), 2014, 31(1): 39-42.
[28] 冯路路, 吴开明, 乔文玮, 等. Nb对高碳钢珠光体球化的影响[J]. 钢铁研究学报, 2020, 32(8): 734-739.
Feng Lulu, Wu Kaiming, Qiao Wenwei, et al. Effect of Nb on spheroidization of pearlitic for high carbon steel[J]. Journal of Iron and Steel Research, 2020, 32(8): 734-739.
[29] Jia N, Shen Y F, Liang J W, et al. Nanoscale spheroidized cementite induced ultrahigh strength-ductility combination in innovatively processed ultrafine-grained low alloy medium-carbon steel[J]. Scientific Reports, 2017, 7(1): 2679.