Microstructure development and metallurgical analysis of the Al–Si contact reaction

The mechanism of the contact reaction of aluminum–silicon was investigated in this paper. By analyzing the results through SEM and EDS, the behavior of the eutectic liquid of aluminum–silicon was studied. SEM photographs showed that the contact reaction took place not only on the Al surface but also over the cross-section. The eutectic liquid of Al–Si was first produced in the Al grain boundary. The results could be analyzed from thermodynamics and dynamics. In order to obtain an ideal brazed joint, a series of experiments was carried out to secure optimized parameters. If suitable conditions were chosen, sound contact reaction brazed joints of Al could be obtained using Si powder as an interlayer.