Brazing ZrB2-SiC ceramics to Inconel 600 alloy without and with Cu foam

Abstract

In this work, we report on impacts of adding a co-filler of Cu composite foam for brazing ZrB2-SiC ceramics and Inconel 600 alloy with the main filler of AgCu. Microstructure, shear strength and fracture surface were studied in details for conditions with and without the Cu foams. Compositions of the brazed joints are determined to Cu(s, s), Ag(s, s) and (Fe, Cr)7C3 phases, regardless the Cu foam presence. However, the Cu(s, s) is quantitatively increased, forming discontinuous block structures. Shear strength of brazed joint was improved from 36 MPa to 77 MPa after introducing the Cu foam. The residual stresses of joint with and without Cu foam were calculated, respectively, for both conditions. A significant reduction of residual stress was found after adding the Cu foam during brazing.