Surface micromorphology and strength formation mechanisms of steering knuckles produced by casting-forging technology

Casting technology plays a crucial role in the advanced production of vehicle parts due to its relatively low manufacturing cost and flexibility. However, a major challenge is to improve surface strength, surface finish, and production efficiency in order to produce the next generation of lightweight, long-lasting, energy-efficient vehicles. In this study, we propose an efficient AlSi7Mg casting-forging technology that significantly enhances the mechanical properties of the samples compared to those produced by casting alone. The ultimate tensile strength (UTS) and elongation were increased from 290 MPa to 11% to 311 MPa and 13%, respectively, which represents an improvement of 7.2% and 18%. Our research results demonstrate that the casting-forging technique introduces favorable and stable microstructural features, including optimized surface quality and refined grains, which improve mechanical properties.