Results in Surfaces and Interfaces (Oct 2024)
Convex structure formation on a Cu substrate by friction stirring using a tool wrapped with Ti foil
Abstract
The bond strength between Cu substrate and epoxy resin is required to be improved in power modules. Surface modification of the Cu substrate improves the bond strength due to the anchor effect. In this study, we propose a new surface modification method using friction stirring. A convex structure was formed on a Cu substrate by friction stirring using a tool wrapped with Ti foil. The microstructure of the modified surface and adhesion with epoxy resin were evaluated. Friction stirring formed a Ti-derived convex structure on the Cu substrate, and Cu and Ti were mixed at the microscale and bonded strongly. The shear bond strength between the modified surface and epoxy resin was 7.9 ± 1.7 MPa, which was twice as strong as that without surface treatment. The Ti-derived convex structure formed on the Cu substrate improved adhesion with epoxy resin.
