Study on Microstructure of Ti(C,N) Based Cermets/40Cr Steel Brazing Joint
In vacuum furnace, using brazing filler of Ag-Cu-Ti, a series of the brazing tests were carried on Ti(C,N) based cermets and 40Cr steel. The microstructure of the joints brazed was evaluated at brazing holding for 10 min, 15min and 30min by SEM, EDS, X-ray spectroscopy. The welding crack of the joints brazed was showed by liquid penetrant test. The results show that elements diffusion is more active and the reaction layer is thicker along with the lengthen of brazing holding time between the filler and based metal. The interfacial products of the joints brazed are mainly that: Cu based solid solution,(Cu,Ni), Ag base solid solution and a little AlCu2Ti IMC on the side of cermets, Ag based solid solution and Cu based solid solution in the brazing filler and(Fe,Ni) with a little TiC granular layer on the side of 40Cr steel.