Study On New Welding Method Of Large Diameter Steel Stud

This paper mainly solves the problem of welding defects on 10mm thick 22SiMn2TiB medium carbon steel with a diameter of 18mmQ235 solid stud,and stud welding welding characteristics and properties of high strength steel based metal to weld appearance is not convex forming and weld porosity problems easily occurred in the welding process.For these defects,a new welding method of large diameter steel studs is proposed:arc welding process,Cu aluminum thermal reaction and Fe aluminum thermal reaction arc stud welding method.In the process of welding power supply used in model BMH-22SV drawn arc stud welding machine,a large number of experiments and planning process experimental route,solving the defects of large diameter steel stud is easy to produce in the drawn arc stud welding machine,improving the performance of armored vehicles and other heavy vehicles.We develop the welding process specification of high strength steel plate between the development with 18mmQ235 steel stud and 10mm thickness of hardened and Tempered Carbon and rational implementation of this topic,about welding methods:rotating arc welding,Cu aluminum thermal reaction-arc stud welding,Fe aluminum thermal reaction-arc stud welding method of welding process tests,and the strength of component,suitable parameters of the SEM,EDS,XRD,metallographic analysis and hardness test.The rotary arc device can effectively control the welding arc trajectory,forming high-quality weld appearance forming,for the 18mm diameter stud,the best welding parameter of the welding joint maximum strength:the input current of the arc welding device is 0.4A and the welding power input current and the pulling arc time are 1250A,1200ms.The defect of solid stud in arc welding is that there will be a hole in the center,resulting in the mechanical property of the weld can not reach the maximum value.Cu aluminum thermal reaction arc welding stud welding method can effectively solve the defects of arc welding,and the liquid metal fluidity of weld pool is enhanced.Because the heat of the thermit reaction increases the total heat input of the weld,forming a complete exterior boss and solving the problem of weld fusion.For 18mm diameter studs,Cu aluminum thermal reaction arc welding stud welding best process parameters:Cu aluminum thermal reaction agent added amount of 2.2g,welding power supply current access value and welding arc time were 1200A,1200ms,the welding joint strength under this parameter reaches 216MPa.The defects of Cu thermit reaction arc stud welding method are metallographic microstructure weld crack,run through the whole weld,and extend to base metal.Aiming at the defects of Cu thermit reaction arc welding,Nanjing University of Science and Technology Wang Kehong teacher team put forward Fe aluminum thermal reaction-arc welding stud welding method to optimize the design,solving the defects of appearance bulge forming,joint blowhole and weld fusion.The addition of the reaction agent directly affects the welding quality.The optimal welding parameters of 18mm diameter steel stud:Fe aluminium thermal reaction agent was added into 2.4G,drawn arc stud welding machine input current value and welding time are respectively 1250A,1200ms,the shear strength of welded joints reached 307MPa.