Ultrasonic Reflectivity of Diffusion Bonds

Solid state welds that bond a piece of metal to a piece of the same metal are increasingly important in industrial applications. Consequently new inspection methods that use ultrasound are being developed based on two characteristics of the weld. One inspection method uses the bond-line’s specular reflectivity to indicate microcracking or porosity [1–4]. A second method measures the attenuation (or velocity shift) to infer changes in the near-bond microstructure of the metal [4,5]. To date both methods give useful but primarily qualitative information on bond integrity