This paper reports the preliminary investigation of the micro-bonding of reinforcement/matrix and reinforcement/reinforcement in a diffusion welded joint for Al2O3p/6061Al composite and analyzes the microstructure and performance of the welded joint. Experimental results show that the interface of the matrix/reinforcement has better bonding only when the diffusion welding temperature is higher than the solid phase line of Al2O3p/6061Al composite. It is found that a critical temperature exists between solid and liquid phase line of the aluminum matrix composite. When the diffusion welding temperature reaches this value, not only the interface of the matrix/reinforcement exhibits better bonding, but also the welded joint can be greatly strengthened, the molten matrix penetrating into the interface of the reinforcement/reinforcement can change the bonding of reinforcement/reinforcement into reinforcement/matrix/reinforcement. Based on the experimental results, the authors firstly point out that the technology on non-interlayer liquid phase diffusion welding can successfully bond Al2O3p/6061Al composite.
