千层钢组织和力学性能分析  

Microstructure and mechanical properties of multilayered steel

作　　者：赵小康[1] 曹睿[1] 张晓波[1] 张瑞华 陈剑虹[1] 

机构地区：[1]兰州理工大学有色金属先进加工与再利用省部共建国家重点实验室,兰州730050 [2]钢铁研究总院,北京100081

出　　处：《焊接学报》2018年第1期45-49,共5页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目(51265028);973计划前期研究专项(2014CB660810)

摘　　要：通过对千层钢SEM观察、拉伸和弯曲性能的表征,分析揭示了千层钢的组织和相应力学性能.分析结果表明,千层钢具有较高的抗拉强度为966 MPa,断后伸长率为17%以及表现出良好的抗弯性能,弯曲至136°时的抗弯强度达到5 451 MPa,弯曲挠度为22 mm.从拉伸断口和弯曲至180°时的微观形貌发现,中间层在断裂过程中形成大块相的脆性开裂和基体成韧窝的断裂特征,在镍薄层和中间层结合处易发生分层开裂;然而两侧的马氏体层和镍薄层结合质量较好,在拉伸时均形成韧窝形态,弯曲时发生大量塑性变形.Microstructure and corresponding mechanical properties of multilayered steel were revealed by SEM observation and analysis of tensile and bending properties. Analysis results show that the tensile strength of multilayered steel is 966 MPa,the elongation is 17% and this material exhibits excellent bending properties,the bending strength is 5 452 MPa,bending deflection is 22 mm when the multilayered steel is bent to 136°.From the tensile fracture and the microscopic appearance of bending to 180°,it can be found that brittle cracking appeared in big block phase of middle layer and dimple fracture characteristics appeared at matrix during the fracture process,delamination cracking were easily induced in the interface between Ni layer and the middle layer; However,there were satisfied interface between the martensitic layer of on both sides and the Ni layer,and a lot of plastic deformation with dimple morphology were produced in the interface between the martensitic layer of on both sides and the Ni layer with during the tension and produced in bending.

关 键 词：千层钢 组织 拉伸性能 弯曲性能 断口 

分 类 号：TG457[金属学及工艺—焊接]