Reactive process and thermal properties of self-propagated SiC_p/Al composites

SiC_p/Al composites with low coefficient of thermal expansion (CTE), high thermal conductivity factor and high SiC content were processed by SHS reaction of SiC-Ti powder compact in the Al melt. The coating of SiC particle developed by SHS improves the wettability between SiC particle and aluminum melt. Composite with high SiC content can be got by gravity precipitation of coated SiC particles in Al melt of 800 ℃. The CTE and thermal conductivity of composite and their relation to SHS reaction were also studied. It was shown that SHS reaction has little effect on CTE of the composite. The intense SHS reaction can harm the thermal conductivity factor of the composite because of the low heat transfer rate of the coating of SiC particle. Proper SHS can be used to process composite with low CTE and high conductivity.