AF1410钢电子束焊接接头组织及性能研究

采用电子束扫描焊和修饰焊工艺对5mm AF1410钢板进行电子束焊接。针对热处理前、后的接头,采用光学显微镜、扫描电镜、硬度仪等对其组织、硬度及拉伸断口进行分析。结果表明:接头热影响区分为浅腐蚀区和深腐蚀区,分别为单一马氏体(M)、M+少量逆转奥氏体(Ar)组织;焊缝区柱状晶分为重熔区、正火区和回火区,晶内为马氏体,晶界附近为残留奥氏体。热处理后,接头组织、显微硬度与母材趋于一致,抗拉强度也达到了母材98%以上,失效裂纹始于热影响区,呈约60°方向扩展并贯穿整个接头。

Study on Microstructrue and Mechanical Properties of Electron Beam Welded AF1410 Joints

Oscillated electron beam welding with cosmetic welding was applied to 5mm AF1410 steel.Microstructural features and tensile failure fractures of joints were examined by means of OM,SEM and microhardness tester.Results showed that the heat affected zone (HAZ) contains light etched zone and dark etched zone,which are composed of martensite (M),M+ reverted austenite (Ar) respectively;the weld zone (WZ) is divided into 3 different zones,namely remelted zone,normalized zone and tempered zone,and occupied by columnar grains,besides martensite exists in intragranular areas and retained austenite (A) exists at intergranular areas.After post-weld heat treatment,microhardness and microstructure of joint are nearly the same as base metal.The room tensile strength of joint reaches 98％ of base metal and all cracks initiate at HAZ and propagate through the whole WZ in60° direction.