Friction Welding Analysis: The Impact of Coolant Variation on Hardness and Tensile Strength of ST 37 Carbon Steel and SS 304 Stainless Steel

Friction welding is a method of joining solid objects that combines rotation rate and pressure between two workpieces. The variables of rotating speed, friction duration, and pressure play crucial roles in determining the quality and results of the welding process. This research focuses on welding different materials using ST 37 steel and Stainless Steel 304, with parameters set at a pressure of 70 Psi, rotational speed of 2300 rpm, and friction time of 60 s while varying the coolant. The workpiece is quenched with different cooling liquids, namely oil, air, and water, to know its effect on the mechanical properties of welding results, such as the hardness and tensile strength of the material after the welding process. The study found that the cooling fluids used in the friction welding method significantly affect the mechanical properties of the workpiece. The highest hardness result of 82.58 HRB was found in the water-cooling liquid variation at the weld area, while the lowest hardness of 81.27 HRB was found in the oil-cooling liquid variation. Similarly, the water-cooling liquid variation had the highest tensile strength of 711.17 N/mm2, while the oil-cooling liquid variation had the lowest tensile strength of 364.13 N/mm2. From these results, the best cooling process is using water media for friction welding different materials between ST 37 carbon steel and Stainless Steel 304.