Aluminum alloys based metal matrix composite have become a significant category of engineering materials due to their ability to provide an effective combination of light weight, decent strength to weight ratio and thermal stability. Despite these advantages, a good number of traditional aluminum alloys continue to be not sufficient in the highly challenging industries like automotive, aerospace, marine, and defense where the material has to endure extreme mechanical and tribological environments. The present review describes the impacts of each of the two materials, SiC and TiB2, and their combination on the properties and performance of the metal matrix composites with aluminum. Combining the two types of reinforcements can result in improved uniformity, enhanced mechanical performance and increased wear resistance of hybrid composites compared to materials reinforced with a single ceramic phase. These composites have been fabricated using a number of methods including stir casting, in situ formation, powder metallurgy and friction stir processing and each has its own advantages and disadvantages. It is established that the addition of SiC may increase the hardness of aluminum composites by approximately 20-50% and the addition of TiB2 may also increase it by approximately 25-50%. With the reinforcements applied concurrently, the gain in hardness can be as much as 40- 70% and correct proportions of the reinforcements have been discovered to boost tensile strength up to 45. Wear tests also indicate significant reductions in wear rate - usually of the order of 50-60% and reduced friction and increased surface stability. Another contribution to the literature, identified in this review, is the existence of a number of significant gaps in research, which can be addressed in future (through the investigation of nano-scale reinforcements and the creation of hybrid ceramics made of multiple particle types).
Bhushan et al. (Thu,) studied this question.