| Dissimilar materials of steel & aluminum stud welding tend to appear defects, and fusion welding is difficult to implement welding of steel & aluminum. So steel stud aluminum dissimilar materials friction stud welding technology is researched. Fusion welding for steel and aluminum alloy welding are more likely to appear intermetallic compound. Intermetallic compound layer thickness is hard to control, so the welding joint is crisp, and it is difficult to meet the requirements.According to the welding test data, the friction stud welding equipment is designed, contents includig are mechanical systems, rotary fixture and signal acquisition system. The device designed has big force of rotation fixture clamping big, not slip while welding.The workbench is satisfied the requirements of stud to bar or stud to plate, and can weld more than one stud on the same piece of plate. Welding pressure can be acquisition, displayed and storage by time. The equipment runs stability, high efficiency and easy.It meets the demand of friction stud welding technology research.Friction stud welding of 45 steel stud and 6061 aluminium alloy is carried out with continuous drive friction welding machine. Through analyzing the appearance of the welding joint, shorten of welded joint, tensile test, microstructure analysis and energy spectrum analysis, discussed the friction welding performance of steel stud-aluminium alloy. Research shows that 45 steel stud and 6061 aluminum alloy with the optimal welding parameters has good friction weldability. Welding joint tensile strength reached 93.5% of aluminum alloy base metal. The grain of welded joint has elaborated beside the weld. There is a certain degree of element diffusion occurs in weld zone. And rotating speed of 1600 r/min, the friction pressure of 117.2 MPa, friction time of 3 s, upsetting force of 312.5 MPa, upset forging pressure keeping time for the 4 s is the optimal process parameters, and the joint tensile strength reached 168.3 MPa. Research the influence of different stud shape on the mechanical properties.And the relationship between the plastic flow of metal and the stud shape. So that the effect of optimal joint shape is clear.Research of steel stud-aluminum plate friction stud welding shows that dissimilar materials of steel stud-aluminum plate can be achieved with reasonable welding process parameters. Welding joints are well-organized, grain refinement and high intensity. The study provides reference data of dissimilar materials of steel and aluminum alloy welding, and makes a contribution to the further research of the steel and aluminum alloy. |
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