| Abstract Scope |
Pinless friction stir welding offers notable advantages in joining metals and polymer composites; however, the influence of magnesium alloy surface structures on joint performance requires further clarification. This study adopts an innovative surface grooving technology to pretreat AZ31 magnesium alloy substrates, exploring how groove geometry affects the mechanical properties and corrosion resistance of Pinless friction stir welding joints between AZ31 magnesium alloy and polyetheretherketone (PEEK). The findings reveal that under thermo-mechanical coupling, molten PEEK infiltrates the grooves on the magnesium alloy surface and solidifies to form macroscopic mechanical interlocking structures. These interlocks improve joint tensile shear strength via geometric constraints, with the enhancement dependent on groove spatial distribution, cross-sectional shape, and density. Despite corrosion damage to the magnesium alloy substrate interface, the interlocking structures preserve effective bonding and maintain joint strength post-corrosion. This work introduces a novel approach to interfacial engineering in dissimilar material joining, optimizing surface structures to enhance both joint strength and corrosion resistance. |