Review in Friction Stud Welding Of Aluminium to Steel

D.S. Samuvel Premkumar

Abstract

The demand for friction stud welded aluminum/steel joints has increased in many significant applications including cryogenics, structural engineering, spacecraft, rocket fuel tanks and high vacuum chambers owing to their superior properties. In automobile engineering, there is a requirement to join a mild steel earthing pin which is in the shape of a stud to an aluminum car body. Aluminum and steel was considered to join using friction stud welding. This review is about the material joining process in dissimilar materials. Mechanical properties, tensile strength of two materials and rotational speed, friction time, and friction pressure are considered as the input process parameters. Output parameters of hardness, impact strength, tensile strength, micro structure association of a welded joints has to be taken by conducting test method of micro-hardness, tensile, impact tests, optical microscopy respectively. The resulting joints made of friction stud welding are higher than the parent materials. Numerical investigation of heat flow in friction stud welding process was carried out for different combination. Results show that the heat dissipation is high at aluminum side whereas the heat dissipation is less in the mild steel side. This is due to the change in material properties of the two dissimilar metals. Since the thermal conductivity of aluminum is high the heat transfer is high in the aluminium side. Bonding mechanism and formation of intermetallic compound at joint interface during friction welding process is still least understood for different combination of materials especially in MMC/metal joints used in critical applications.The demand for friction stud welded aluminum/steel joints has increased in many significant applications including cryogenics, structural engineering, spacecraft, rocket fuel tanks and high vacuum chambers owing to their superior properties. In automobile engineering, there is a requirement to join a mild steel earthing pin which is in the shape of a stud to an aluminum car body. Aluminum and steel was considered to join using friction stud welding. This review is about the material joining process in dissimilar materials. Mechanical properties, tensile strength of two materials and rotational speed, friction time, and friction pressure are considered as the input process parameters. Output parameters of hardness, impact strength, tensile strength, micro structure association of a welded joints has to be taken by conducting test method of micro-hardness, tensile, impact tests, optical microscopy respectively. The resulting joints made of friction stud welding are higher than the parent materials. Numerical investigation of heat flow in friction stud welding process was carried out for different combination. Results show that the heat dissipation is high at aluminum side whereas the heat dissipation is less in the mild steel side. This is due to the change in material properties of the two dissimilar metals. Since the thermal conductivity of aluminum is high the heat transfer is high in the aluminium side. Bonding mechanism and formation of intermetallic compound at joint interface during friction welding process is still least understood for different combination of materials especially in MMC/metal joints used in critical applications.

Abstract

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