高压低温回火对铌微合金化高碳钢组织与性能的影响  

Effect of high-pressure low-temperature tempering on microstructure and properties of a niobium microalloyed high-carbon steel

作　　者：赵伟男 卢超 曹建春[1] 徐朝勇 杨立盛 张金昌 Zhao Weinan;Lu Chao;Cao Jianchun;Xu Chaoyong;Yang Lisheng;Zhang Jinchang(Faculty of Materials Science and Engineering,Kunming University Science and Technology,Kunming Yunnan 650093,China)

机构地区：[1]昆明理工大学材料科学与工程学院,云南昆明650093

出　　处：《金属热处理》2025年第3期32-37,共6页Heat Treatment of Metals

基　　金：国家自然科学基金(52364052);中信金属-CBMM铌技术推广合作项目(2022FWNB-30123(M1162));中信-CBMM铌钢研究与开发项目(2017FWNB-3079)。

摘　　要：利用CS-IB型六面顶压机对0.86%C-0.045%Nb高碳钢淬火态试样进行不同高压下200℃回火处理,并与常压回火态试样进行对比,探究高压对含铌高碳钢淬回火后组织与性能的影响。结果表明,试验钢经1100℃淬火,在1、3、5 GPa高压下200℃回火后,组织为回火马氏体和少量残留奥氏体,与常压回火态相比,回火马氏体基体上出现NbC颗粒;通过ICP-OES对不同压力下回火态试样进行固溶Nb含量的测定发现,随着压力的增加,钢基体中固溶Nb含量降低,进一步表明高压可有效促进NbC低温析出。随着压力的升高,试样钢抗拉强度和断裂总延伸率呈现先增加后降低的趋势,在1 GPa高压下200℃回火后试验钢力学性能最佳,其抗拉强度为1556 MPa,断裂总延伸率为6.45%,与常压回火态相比,分别提高了280 MPa和1.12%。0.86%C-0.045%Nb high-carbon steel specimens were quenched and then tempered at 200℃under different pressures using a CS-IB type hexagonal top press.The effects of high pressure on the microstructure and properties of the niobium-containing high-carbon steel after quenching and tempering were compared with those of specimens tempered at atmospheric pressure.The results show that after quenching at 1100℃and tempering at 200℃under pressures of 1,3 and 5 GPa,the microstructure of the tested steel consists of tempered martensite with a small amount of retained austenite.Compared to the atmospheric pressure tempering condition,the NbC particles are observed in the tempered martensite matrix.The solution Nb content in the tempered specimens under different pressures determined by ICP-OES reveals that the solution Nb content in the steel matrix decreases with the increase of pressure.This shows that high pressure effectively promotes the low-temperature precipitation of NbC.As the pressure increases,the tensile strength and percentage total extension at fracture of the tested steel initially increase and then decrease.The best mechanical properties of the tested steel are obtained after tempering at 200℃under 1 GPa high pressure,with a tensile strength of 1556 MPa and percentage total extension at fracture of 6.45%.Compared with the atmospheric pressure tempering condition,the tensile strength and percentage total extension at fracture are increased by 280 MPa and 1.12%,respectively.

关 键 词：高碳钢 NB微合金化 高压热处理 力学性能 

分 类 号：TG142[一般工业技术—材料科学与工程]