Bonding strength in scarf joint by diffusion bonding of superplastic aluminum alloy.

In order to examine the possibility of combined application of SuperPlastic Forming and Diffusion Bonding (SPF/DB) to superplastic aluminum alloy sheet, relationships between bonding conditions and bonding strength were investigated experimentally. Superplastic A7475 sheet was diffusion-bonded in scarf joint configuration with various scarf angles at 788K in the air atomosphere, then bonding strength of the joint was measured by tensile test at room temperature. The stress state on the interface of the joint was taken into consideration to evaluate the strength of the bonding area. Estimation of bond strength reveals that sufficient high strength could be obtained if the bonding conditions are ordered properly.