Production of Aluminium-Silicon Carbide Cast Particle Composites Without Magnesium

To produce Al matrix cast particle composites, wettability of the ceramic particles by liquid Al is essential. To improve wettability, elements such as Mg, Ce etc. are added into Al alloy prior to incorporation of the ceramic particles. In other methods,ceramic particles are incorporated into solid-liquid slurry of Al alloy: metalceramic powder compacts are slowly dissolved into the Al alloy or particles are preheated before incorporation into Al alloy.In the present study, silicon carbide and alumina particles were mixed with Al-Cu (50:50) piaster alloy powder in a required proportion to produce Al-4.5 Cu alloy- 15 wt% particle composites by vortex method. Success was achieved to incorporate SiC particles in an Al melt without Mg. whereas in case of alumina particles, the viscosity of the melt was too high after addition of about half of the required amount of particles. The fluidity of the Al alloy-SIC composite melt was sufficient to pour in graphite moulds. The mechanism of this novel approach of production of cast ceramic particle composites by vortex method without Mg is discussed