Phase transformation behavior of non-quenched and tempered NM400 multiphase wear-resistant steel

doi:10.13251/j.issn.0254-6051.2022.12.038

Abstract

Abstract: In order to further optimize the different microstructure ratios of non-quenched and tempered NM400 multiphase wear-resistant steel, the Gleeble-3800 thermal simulation testing machine was used to explore the microstructure transformation law of the tested steel under continuous cooling conditions, and the metallographic method and the hardness method were combined to draw the dynamic continuous cooling transformation (CCT) curves. The results show that when the cooling rate is lower than 1 ℃/s, the microstructure of the steel is composed of ferrite+granular bainite+pearlite, there are some coarse austenite grains transform into granular bainite and pearlite either. When the cooling rate is 5-40 ℃/s, the pearlite transformation no longer occurs, and the microstructure is composed of ferrite+bainite+martensite. With the increase of cooling rate, the martensite content increases and the hardness increases. In addition, under different step cooling schemes, the lower middle cooling temperature and longer air cooling time are beneficial to the transformation of ferrite and bainite, and the retained austenite content increases with the increase of ferrite content. Due to higher Ms point, the martensite lath of the steel is wide, and self-tempering phenomenon occurs in the steel.

Key words: NM400 steel, CCT curves, lath martensite, step cooling, retained austenite

CLC Number:

TG142.1

Li Guannan, Lei Minggang, Chen Haotian, Lü Dewen. Phase transformation behavior of non-quenched and tempered NM400 multiphase wear-resistant steel[J]. Heat Treatment of Metals, 2022, 47(12): 228-233.

References

[1]温二丁. NM600耐磨钢的组织性能调控及磨损特性研究[D]. 北京: 北京科技大学, 2019.
[2]唐春霞, 曹文全. 耐磨钢的国内生产现状及发展前景[J]. 宽厚板, 2018, 24(3): 37-41.
Tang Chunxia, Cao Wenquan. Current production situation and development prospect of wear-resistant steel at home[J]. Wide and Heavy Plate, 2018, 24(3): 37-41.
[3]宋红宇, 李灿明, 周平, 等. 低成本NM400高强低合金耐磨钢的开发[J]. 轧钢, 2012, 29(4): 1-3.
Song Hongyu, Li Canming, Zhou Ping, et al. Development of high strength low alloy wear-resistant steel NM400[J]. Steel Rolling, 2012, 29(4): 1-3.
[4]Ortner H M, Ettmayer P, Kolaska H, et al. The history of the technological progress of hardmetals[J]. International Journal of Refractory Metals and Hard Materials, 2015, 49: 3-8.
[5]曹艺, 王昭东, 吴迪, 等. NM400高强度低合金耐磨钢的组织与性能[J]. 东北大学学报(自然科学版), 2011(2): 241-244.
Cao Yi, Wang Zhaodong, Wu Di, et al. Microstructure and mechanical properties of HSLA wear-resistant steel NM400[J]. Journal of Northeastern University (Natural Science), 2011(2): 241-244.
[6]李灿明. 淬火工艺对耐磨钢NM400组织性能的影响[J]. 金属热处理, 2021, 45(6): 69-73.
Li Canming. Effect of quenching on microstructure and properties of wear-resistant steel NM400[J]. Heat Treatment of Metals, 2021, 45(6): 69-73.
[7]王中学, 郭伟达, 李涛. 0.15%镍对NM400钢显微组织和低温性能的影响[J]. 金属热处理, 2019, 44(10): 152-155.
Wang Zhongxue, Guo Weida, Li Tao. Effect of 0.15%Ni on microstructure and low temperature toughness of NM400 steel[J]. Heat Treatment of Metals, 2019, 44(10): 152-155.
[8]王自力, 陈荣发, 郑志伟, 等. 42CrMo钢活塞杆表面氧氮复合渗层的显微组织和耐磨性能[J]. 金属热处理, 2021, 46(8): 225-229.
Wang Zili, Chen Rongfa, Zheng Zhiwei, et al. Microstructure and wear resistance of oxynitriding layer on piston rod surface of 42CrMo steel[J]. Heat Treatment of Metals, 2021, 46(8): 225-229.
[9]José Rendón, Mikael Olsson. Abrasive wear resistance of some commercial abrasion resistant steels evaluated by laboratory test methods[J]. Wear, 2009, 267: 2055-2061.
[10]王幸, 李红英, 汤伟, 等. 一种高强度钢的CCT曲线的测定与分析[J]. 中南大学学报(自然科学版), 2021, 52(4): 1090-1098.
Wang Xing, Li Hongying, Tang Wei, et al. Determination and analysis of CCT curve of a high strength steel[J]. Journal of Central South University (Science and Technology), 2021, 52(4): 1090-1098.
[11]陈鑫, 徐光, 姚籽杉, 等. NM400马氏体耐磨钢静态CCT曲线[J]. 特殊钢, 2021, 42(3): 63-66.
Chen Xin, Xu Guang, Yao Zishan, et al. Static CCT curve of martensite wear-resistant steel NM400[J]. Special Steel, 2021, 42(3): 63-66.
[12]霍喜伟. Cr对20MnSiV门架型钢动态CCT曲线和性能的影响[J]. 金属热处理, 2021, 46(7): 89-93.
Huo Xiwei. Effect of Cr on dynamic CCT curves and properties of 20MnSiV gantry steel[J]. Heat Treatment of Metals, 2021, 46(7): 89-93.
[13]Ghosh S, Mula S. Thermomechanical processing of low carbon Nb-Ti stabilized microalloyed steel: Microstructureand mechanical properties[J]. Materials Science and Engineering A, 2015, 646: 218-233.
[14]Morito S, Tanaka H, Konishi R. The morphology and crystallography of lath martensite in Fe-C alloys[J]. Acta Materialia, 2003, 51: 1789-1799.
[15]刘宗昌, 袁长军, 计云萍, 等. 贝氏体铁素体的形核[J]. 材料热处理学报, 2011, 32(10): 74-79.
Liu Zongchang, Yuan Changjun, Ji Yunping, et al. Study on nucleation of bainite ferrite [J]. Transactions of Materials and Heat Treatment, 2011, 32(10): 74-79.
[16]Li X, Ma X, Subramanian S V, et al. Influence of prior austenite grain size on martensite-austenite constituent and toughness in the heat affected zone of 700 MPa high strength linepipe steel[J]. Materials Science and Engineering A, 2014, 616: 141-147.
[17]Wen E D, Song R B, Xiong W M, et al. Effect of tempering temperature on microstructures and wear behavior of a 500 HB grade wear-resistant steel[J]. Metals, 2019, DOI: 10.3390/met9010045.