Effect of solution temperature on microstructure and mechanical properties of ultra-high strength steel G33

doi:10.13251/j.issn.0254-6051.2021.07.030

Abstract

Abstract: Effect of solution treatment temperature on microstructure and properties of a ultra-high strength steel G33 was investigated by means of optical microscope, scanning electron microscope and physicochemical phase analysis. The results show that the undissolved phase of M₆C, VC and NbN exist in the lath martensite matrix of the G33 steel after solution treating at 860 ℃, in which, M₆C is dominant. With the increase of solution temperature, the undissolved phase is dissolved rapidly, VC and M₆C phases are dissolved completely at 940 ℃ and 980 ℃, respectively. Due to the dissolving of M₆C and VC phases, the microcrack is difficult to initiate for lack of nucleation sites. Meanwhile, the solid solution amount of alloy elements in the substrate is increased, which enhances the solid solution strengthening effect and improves the impact property of the tested steel while maintaining the high strength (grade of 2000 MPa).

Key words: ultra-high strength steel, solution temperature, mechanical properties, microstructure, undissolved phase

CLC Number:

TG135.1

Xiong Jinsheng, Ning Jing, Su Jie, Jiang Qingwei. Effect of solution temperature on microstructure and mechanical properties of ultra-high strength steel G33[J]. Heat Treatment of Metals, 2021, 46(7): 160-164.

References

[1] 李杰, 李志, 颜鸣皋. 高合金超高强度钢的发展[J]. 材料工程, 2007(4): 61-65.
Li Jie, Li Zhi, Yan Minggao. Development of high-alloy ultra-high strength steel[J]. Journal of Materials Engineering, 2007(4): 61-65.
[2] 王涛亮, 路妍, 任凤章, 等. 低合金超高强度钢研究进展[J]. 金属热处理, 2015, 40(2): 13-20.
Wang Taoliang, Lu Yan, Ren Fengzhang, et al. Research progress of ultra-high strength low alloy steels[J]. Heat Treatment of Metals, 2015, 40(2): 13-20.
[3] 杨尚林, 常天义, 马茂元. 钨对18Cr₂Ni₄WA钢相变、组织和性能的影响[J]. 哈尔滨工程大学学报, 1996, 17(3): 107-112.
Yang Shanglin, Chang Tianyi, Ma Maoyuan. Effects of wolfram on the phase-transformation, structure and performance of 18Cr₂Ni₄WA steel[J]. Journal of Harbin Engineering University, 1996, 17(3): 107-112.
[4] Lu Y, Su J, Wang J H, et al. Effect of W on microstructure of high strength and toughness steels[J]. Acta Metallurgica Sinica(English Letters), 2011, 24(6): 423-431.
[5] Zhou S M, Cheng X W, Zhang Y J, et al. Factors affecting the mechanical properties of ultra-high-strength bainitic steel containing W and 0.33 mass%C[J]. Journal of Iron and Steel Research(International), 2016, 23(3): 289-296.
[6] 周士猛, 程兴旺, 张由景, 等. 新型超高强度钢的高温形变热处理[J]. 材料工程, 2016, 44(5): 37-41.
Zhou Shimeng, Cheng Xingwang, Zhang Youjing, et al. High temperature thermo-mechanical treatment of novel ultra-high-strength steel[J]. Journal of Materials Engineering, 2016, 44(5): 37-41.
[7] Kwon H, Kim C M, Lee K B, et al. Effect of alloying additions on secondary hardening behavior of Mo-containing steels[J]. Metallurgical and Materials Transactions A, 1997, 28(3): 621-627.
[8] 章伟钢, 周芸, 刘少尊, 等. Mo与Co含量对18Ni马氏体时效钢性能的影响[J]. 金属热处理, 2018, 43(4): 48-52.
Zhang Weigang, Zhou Yun, Liu Shaozun, et al. Effects of Mo and Co content on properties of 18Ni maraging steel[J]. Heat Treatment of Metals, 2018, 43(4): 48-52.
[9] Veerababu R, Prasad K S, Karamched P S, et al. Austenite stability and M₂C carbide decomposition in experimental secondary hardening ultra-high strength steels during high temperature austenitizing treatments[J]. Materials Characterization, 2018, 144: 191-204.
[10] Sim H S, Cho K S, Lee K B, et al. Tensile properties in W-containing high Co-Ni steels[J]. Materials Science and Engineering A, 2007, 449-451: 1143-1146.
[11] Zhao S, Cheng X, Li S, et al. Effect of austenitizing temperature on microstructure and mechanical properties of an ultrahigh strength high alloy G33 steel[J]. Materials Research Innovations, 2013, 17(S1): 277-281.
[12] Babu N K, Suresh M R, Sinha P P, et al. Effect of austenitizing temperature and cooling rate on the structure and properties of a ultrahigh strength low alloy steel[J]. Journal of Materials Science, 2006, 41(10): 2971-2980.
[13] 何毅, 杨柯, 孔凡亚, 等. 超高强度18Ni无钴马氏体时效钢的力学性能[J]. 金属学报, 2002, 38(3): 278-282.
He Yi, Yang Ke, Kong Fanya, et al. Mechanical properties of ultra-high-strength 18Ni cobalt-free maraging steel[J]. Acta Metallurgica Sinica, 2002, 38(3): 278-282.
[14] 宁静, 杨卓越, 苏杰, 等. 固溶温度对30Cr4Si2NiMoWNb超高强度钢力学性能的影响[J]. 钢铁研究学报, 2017, 29(12): 1030-1034.
Ning Jing, Yang Zhuoyue, Su Jie, et al. Influence of solution treatment temperature on mechanical properties of 30Cr4Si2NiMoWNb steel[J]. Journal of Iron and Steel Research, 2017, 29(12): 1030-1034.
[15] 冯亚亚, 卜春成, 徐驰, 等. 奥氏体化温度对新型低合金超高强度钢组织及力学性能的影响[J]. 金属热处理, 2018, 43(2): 160-165.
Feng Yaya, Bu Chuncheng, Xu Chi, et al. Effect of austenitizing temperature on microstructure and mechanical properties of a new designed low alloy ultrahigh strength steel[J]. Heat Treatment of Metals, 2018, 43(2): 160-165.
[16] 王飞, 张英杰, 杨卓越. 奥氏体化温度对W、Mo强化超高强度钢强韧性的影响[J]. 金属热处理, 2015, 40(7): 130-132.
Wang Fei, Zhang Yingjie, Yang Zhuoyue. Effect of austenitizing temperature on strength-toughness of ultra-high strength steel containing W and Mo[J]. Heat Treatment of Metals, 2015, 40(7): 130-132.