Heat generation and steel fragment effects on friction stir welding of aluminum alloy with steel
Pankaj Kaushik, Dheerendra Kumar Dwivedi
Abstract
Joining two dissimilar materials, like aluminum and steel, has been a topic of great importance in modern engineering applications. Therefore, this research expounds on joining aluminum alloy (Al5052) with low-carbon mild steel using friction stir welding. A novel approach is employed that quantifies the discontinuities (steel debris and voids) in the weld stir zone using image analysis. Furthermore, a parametric investigation was conducted following a full factorial approach with three tool rotational and traverse speed levels, and a heat input factor (ω2/v) was derived through theoretical modeling of process parameters. The heat input factor was substantiated experimentally with thermal cycle measurements. Results revealed that both the ω2/v factor and the extent of discontinuities determined the soundness and strength of the weld joints. A low rotational speed of 386 revolutions/minute and moderate traverse speed of 140 mm/minute, having minimal discontinuities, rendered maximum joint strength of approximately 212 MPa.