Experimental and numerical investigation on temperature analysis and process optimization in friction stir welding of CuZn40 brass alloys

Friction stir welding (FSW) is a solid-state joining process widely used for its advantages in welding various materials, including CuZn40 brass. CuZn40 brass, characterized by its good hot formability and superior mechanical properties attributed to its higher zinc content, presents an attractive option for industrial applications. This study delves into the temperature distribution and mechanical properties of CuZn40 brass joints created through friction stir welding (FSW). ABAQUS software and the Goldak method are utilized to simulate temperature profiles during the welding process, with validation against experimental measurements revealing a close agreement, showing a temperature difference of approximately 22%. Fifteen practical tests are conducted to evaluate the impact of various process parameters, such as rotational speed, traverse speed, and tool geometry, on weld strength and temperature evolution. Using response surface methodology (RSM) for optimization, optimal parameter combinations are identified to maximize ultimate tensile strength. The RSM model predicts a maximum strength of 381.79 MPa, which deviates by 55.18 MPa from the experimentally measured maximum of 326.61 MPa. The study demonstrates the effectiveness of process optimization in enhancing mechanical properties, offering practical insights for improving CuZn40 brass welding processes in industrial applications.