Preliminary investigation on joining performance of SiCp-reinforced aluminium metal matrix composite (Al/SiCp-MMC) by vacuum brazing

The present study has investigated the joining performance of SiC particulate reinforced aluminium metal matrix composite (Al/SiCp-MMC) by vacuum brazing process. After the joints brazed with Al-Si-Mg foil brazing filler metal at different brazing batches, both the mechanical properties and the microstructures of brazed joints were estimated. Moreover, the influence of SiCp size, SiCp volume percentage and the brazing parameters on bonding quality of the joints have also been discussed in detail. The results have revealed that the bonding quality either in SiCp/Al interface or in SiCp/SiCp interface belongs to weak bonding, and the results also show that under the same brazing parameters condition, the strength of brazed joints decreases along with increasing the SiCp volume percentage. In addition, the results also indicate that for a constant SiCp volume percentage the strength of brazed joints decreases when SiCp size increases. These results are very useful for the joining design of discontinuously reinforced metal matrix composites and further for the optimum design of composition of composites. (C) 1999 Elsevier Science Ltd. All rights reserved.