Fracture Variation of Welded Joints at Various Temperatures in Liquid-Phase-Pulse-Impact Diffusion Welding of Particle Reinforcement Aluminum Matrix Composites

Abstract

The fracture variation of liquid-phase-pulse-impact diffusion welding (LPPIDW) welded joints of aluminum matrix composites (ACMs: SiC p /A356, SiC p /6061Al, and Al 2 O 3p / 6061Al) was investigated. Results show that under the effect of pulse-impact (i) initial pernicious contact state of reinforcement particles changes from reinforcement (SiC, Al 2 O 3 )/reinforcement (SiC, Al 2 O 3 ) to reinforcement (SiC, Al 2 O 3 )/matrix/reinforcement (SiC, Al 2 O 3 ) and (ii) the fracture of welded joints with optimal processing parameters is the dimple fracture. Meanwhile, scanning electron microscope (SEM) of the fracture surface shows some reinforcement particles (SiC, Al 2 O 3 ) in the dimples. Moreover, the slight reaction occurs at the interfaces of SiCp/6061Al, which is propitious to improve the property of welded joints because of the release of internal stress caused by the heteromatches between the reinforcements and matrix. Consequently, aluminum matrix composites (SiC p /A356, SiC p /6061Al, and Al 2 O 3p /6061Al) were welded successfully.