Development of aluminium composites with in situ formed AlTiSi reinforcements through infiltration

An in situ AlTiSi ternary phase local reinforced aluminum MMCs composite was successfully fabricated by combustion synthesis and nonpressure infiltration course. XRD results show that the reinforced region of the composite is composed of Al and ternary AlTiSi phase with the composition closing to Ti(Al0.8Si0.2)3. The volume fraction of reinforcement can be controlled by adjusting Al content in compacts. SEM results show that the morphologies of the AlTiSi particles are polygonal and/or spherical. There exists some residual Ti surrounding by AlTiSi phase in the composites. In addition, there is some residual Si in the matrix in the form of Al-Si binary eutectic. The wettability between AlTiSi reinforcement and Al matrix is very good, and the reinforcement lies in the center of α-Al dendritic.