Brazing of C/C Composites and TC4 with Inserting Cu/Mo Foils

Active filler metal(TiZrNiCu) was used to increase the wettability and Cu/Mo foils were added to release residual stress and increase the mechanical properties of C/C composite/TC4 brazed joints. The shear strength of the joint was 21MPa with Cu/Mo composite foils, which was more than those with no foil (5MPa) and with Mo single foil (6MPa). There were no defects in the brazed joints with Cu/Mo composite foils but some cracks existed at the interface of filler metal and C/C composite with no foil and with Mo single foil. The distribution of residual stress of the brazed joint was simulated by FEM calculation. It was showed that the residual stress of the joint would be released with inserting foil. The releasing the residual stress of Cu/Mo composite foils was better than that of Mo single foil.