Experimental and Numerical Study of Interfacial Fracture Parameters of a Brazed Joints

International audienceThis paper deals with an identification methodology of the interfacial fracture parametersto predict the lifetime of a metallic brazed joint. The methodology is based on an experimentalnumericalstudy whereby the optimal parameters are obtained. The experimental data, using thescanning electron microscope analysis, allowed approving that failure of the assembly based AuGesolder seems first to appear near the interfaces. These results were confirmed by micrographsanalysis of the solder/insert and solder/substrate interfaces. Then, using shear test results andparametric identification coupled with a finite elements model (FEM) simulation, the damageconstitutive law of the interfacial fracture based on a bilinear cohesive zone model are identified.The agreement between the numerical results and the experimental data shows the applicability ofthe cohesive zone model to fatigue crack growth analysis and life estimation of brazed joints