1.2 GPa级TRIP钢微观形貌特征及增强增塑性机制研究  

Research on microstructure characteristics and strengthening- plasticizing mechanism of 1.2 GPa grade TRIP steel

作　　者：侯晓英 曹光明 孙卫华 王业勤 刘培星 任东 HOU Xiaoying;CAO Guangming;SUN Weihua;WANG Yeqin;LIU Peixing;REN Dong(Shandong Iron and Steel Group Rizhao Co.,Ltd.,Rizhao 276805,Shandong,China)

机构地区：[1]山东钢铁集团日照有限公司,山东日照276805

出　　处：《钢铁研究学报》2022年第3期288-295,共8页Journal of Iron and Steel Research

基　　金：山东省重点研发计划(重大科技创新工程)资助项目(2019TSLH0103)。

摘　　要：研究了1.2 GPa级TRIP钢微观形貌特征及增强增塑性机制。结果表明,将热轧初始微观组织调控为针状贝氏体组织,有利于将材料组织调控为贝氏体铁素体基体,当退火温度降低至910℃,厚度为50~100 nm的第二相残余奥氏体呈片层状存在于贝氏体铁素体板条间;基体中V(C,N)的相间析出对强度贡献大于200 MPa,且当平均列间距由34.6 nm减小至28.2 nm,析出粒子直径范围由3~8 nm减小至2~5 nm,强度贡献可增加约40 MPa。在两相变形机制协调作用时,45.1%的大角度晶界以及高密度位错塞积均可有效抑制塑性变形过程中的裂纹扩展,而晶体学特征对变形过程中位错的运动又具有约束作用,最终使得强塑性同步提高。The microstructure characteristics and strengthening-plasticizing mechanism of 1.2 GPa grade TRIP steel were investigated.The results indicate that the bainitic ferrite martrix is obtained advantageously,through the needle-like bainite is controlled for the initial hot-rolled microstructure.When the anneal temperature is decreased to 910 ℃,the lamellar retained austenites with the width within the 50-100 nm are distributed between the lath of bainitic ferrite;the contribution of the V(C,N) interphase precipitation to the strength is more than 200 MPa.The contribution of strength can be increased by 40 MPa,when the average spacing is decreased from 34.6 nm to 28.2 nm and the range of particle diameter is decreased from 3-8 nm to 2-5 nm.With the action of the compatible deformation between dual phases,both the 45.1% of high-angle grain boundary and the high density dislocation pile-up can inhibit effectively the crack propagation during plastic deformation,however,the crystallographic features have also restriction effect to dislocation motion in deformation,then finally the tensile strength and ductility of products are improved simultaneously.

关 键 词：TRIP钢 微观形貌 增强增塑性机制 

分 类 号：TG142.1[一般工业技术—材料科学与工程]