In-Situ synthesized TiC nano-flakes reinforced C/C composite-Nb brazed joint

摘要

AbstractBrazing C/C composite to Nb is often associated with the problem of high residual stress, resulting in low-strength joints. To overcome these problems, here we carried out a simple polymer carbonization process to acquire uniform carbon-covered Cu foam composite interlayer, which was subsequently used for soundly brazing C/C composite and Nb with the assembly of C/C composite/Ag-Cu-Ti foil/C-Cu foam/Ag-Cu-Ti foil/Nb. Microstructure and mechanical properties of the joints were well investigated. The carbonization reacted with Ti elements, forming uniformly distributedin-situTiC nano-flakes in the joint seam by virtue of the porous Cu foam skeleton. Results present that thein-situTiC nano-flakes not only greatly reduced the thermal expansion coefficient but also effectively impeded the Cu solid solutions agglomeration. The average shear strength of the joint brazed with 3% C-Cu (wt.%) foam interlayer reached ～52.8MPa with the brazing temperature of 880°C for 10min.]]>