Wetting behavior and reaction layer formation in C/SiC composite-titanium alloy joints

The present study investigates the effect of brazing parameters on reaction layer formation, and mechanical properties of C/SiC composite-Ti6Al4V alloy joints produced by brazing technique. The wetting mechanism of the C/SiC composite surface by the Ag-Cu-Ti-based active brazing filler alloy has also been studied and correlated with the reaction layer formation.The strength of C/SiC composite/Ti6Al4V alloy joints increased at first and then decreased with increasing reaction layer thickness. The joints with ⁓1-µm-thick reaction layer, which were obtained by brazing at 915°C for 15 min, had the highest shear strength of ⁓33 MPa. Brazing filler alloy presented a minimum contact angle of 15° on the C/SiC composite surface at 915°C during the wetting experiments. 915°C and 15 min were determined to be the optimised brazing parameters to ensure almost complete wetting and a uniform reaction layer for effective adhesion of the C/SiC composite surface.