不同铁素体形态的FB双相钢的扩孔性能和原位拉伸实验研究  

Hole-expansion properties and SEM in-situ tensile test of FB dual phase steels with different ferrite morphologies

作　　者：叶校瑛 刘杰 温欣 蒋波[2] 曾艳 YE Xiaoying;LIU Jie;WEN Xin;JIANG Bo;ZENG Yan(School of Mechanical Engineering,Tangshan Polytechnic University,Tangshan 063299,Hebei,China;School of Materials Science and Engineering,University of Science and Technology Beijing,Beijing 100083,China)

机构地区：[1]唐山工业职业技术大学机械工程学院,河北唐山063299 [2]北京科技大学材料科学与工程学院,北京100083

出　　处：《钢铁研究学报》2025年第2期198-208,共11页Journal of Iron and Steel Research

基　　金：河北省高等学校科学技术研究项目(QN2024223)。

摘　　要：通过对C-Si-Mn-Nb-Ti体系的双相钢进行控轧控冷实验,分别获得了具有多边形铁素体组织和具有针状铁素体组织的铁素体贝氏体(FB)双相钢。在扩孔实验和SEM原位拉伸实验中,具有针状铁素体组织的FB双相钢表现出了更高的扩孔率、屈服强度、抗拉强度和伸长率。在塑性变形过程中,针状铁素体组织中形成的显微孔洞更加细小和分散。由于针状铁素体细小且交错分布,有效地降低应力集中,因此在应力传导过程中导致新的、微小的孔洞生成,可以有效地阻止宏观裂纹的扩展。因此具有针状铁素体组织的FB双相钢具有更低的缺陷敏感性和更好的成形性能。By conducting controlled rolling and cooling tests on dual phase steels of C-Si-Mn-Nb-Ti chemical system,ferrite bainite(FB)dual phase steels with polygonal ferrite structure and acicular ferrite structure were obtained,respectively.FB dual phase steel with acicular ferrite structure showed higher hole-expansion ratio,higher yield strength,tensile strength,and better elongation in the expansion and SEM in-situ tensile tests.During the plastic deformation process,the micro voids formed in acicular ferrite structure are finer and more dispersed.Due to its small and staggered distribution of acicular ferrite,it effectively reduces stress concentration,resulting in the generation of new and small voids during stress transmission,effectively preventing the propagation of macroscopic cracks.Therefore,FB dual phase steel with acicular ferrite structure has lower defect sensitivity and better formability than that with polygonal ferrite structure.

关 键 词：FB双相钢 铁素体形态 力学性能 扩孔率 SEM原位拉伸实验 

分 类 号：TG142.1[一般工业技术—材料科学与工程]