Hugoniot, Hugoniot elastic limit, and spall strength of selected braze alloys before and after annealing*

A variety of braze alloys which support joining of ceramics to metals have been developed. If the joint will be subjected to high strain-rate loading during its regular service, understanding the dynamic strength of the braze material is necessary as well as the bond strength to each of the joining materials. Here we present gas gun experiments on three conventional braze alloys, OFHC copper, silver, and Cusil®, plus the active braze alloy Ticusil®, over the stress range 4.0-8.8 GPa. Tests were conducted using as-received material and samples annealed to simulate the brazed condition. Velocity measurements were conducted using both VISAR and PDV and were evaluated to determine the dynamic yield strength and Hugoniot elastic limit, peak Hugoniot stress, and spall strength.