摘要
采用定量金相、SEM、TEM及XRD等检测技术结合室温拉伸试验,研究了预淬火处理对淬火-配分处理后超高强QP钢组织演变和力学性能的影响。结果表明:与未经预淬火的样品相比,经950℃预淬火的样品呈现细化的层片状组织,残余奥氏体以薄膜状为主并有少量块状,该组织有利于TRIP效应的发挥,同时可阻碍裂纹扩展,提高了实验钢的强塑性,在抗拉强度超过1200 MPa的情况下伸长率接近20%;当预淬火温度为990℃时,实验钢的组织呈等轴状特征,马氏体回火程度较高,造成残余奥氏体多呈块状分布而不利于TRIP效应发挥,加之组织内贝氏体及二次马氏体含量减少导致其强塑积下降。
The effect of pre-quenching treatment on microstructure evolution and mechanical properties of ultra-high strength QP steel after quenching and partitioning(QP)treatment was studied by means of quantitative metallography,SEM,TEM and XRD techniques.The results show that compared with the sample without pre-quenching,the sample with pre-quenching at 950℃has refined lamellar microstructure,the retained austenite is mainly film-like and it also has a small amount of blocky ones.The microstructure is beneficial to play the TRIP effect and hinder the crack propagation,thus,improving the strength and ductility of the steel,and an ultra-high strength of 1200 MPa is accompanied by an elongation close to 20%.However,when the pre-quenching temperature is 990℃,the microstructure of the experimental steel is equiaxed,the martensitic tempering degree is higher,resulting in the domination of blocky retained austenite,which is unfavorable to play the TRIP effect.While the decrease of the amount of bainite and secondary martensite further reduces the strength and ductility of the experimental steel.
作者
朱娜琼
许明珠
沈超
李麟
ZHU Naqiong;XU Mingzhu;SHEN Chao;LI Lin(School of Intelligent Manufacturing and Control Engineering,Shanghai Polytechnic University,Shanghai 201209,China;School of Materials Science and Engineering,Shanghai University,Shanghai 200444,China)
出处
《热加工工艺》
北大核心
2025年第15期105-110,共6页
Hot Working Technology
基金
国家自然科学基金项目(51971127)。
关键词
预淬火处理
QP钢
显微组织
力学性能
TRIP效应
pre-quenching treatment
QP steel
microstructure
mechanical properties
TRIP effect
