Thermal properties of a high volume fraction SiC particle-reinforced pure aluminum composite

With dual-sized SiC particles, a 70 vol% SiCp/pure Al composite was fabricated by squeeze casting technology. The composite was subjected to a thermal cycling test between 20 and 150°C. A large residual tensile strain was observed at the end of the first cycling, but the residual length changes were reduced with the following cyclings. It was demonstrated that the thermal stress during the cycling process played an important role in the dimensional change. The composite coefficients of thermal expansion during thermal cyclings ranged from 9.14 × 10 ^-6 to 9.28 × 10 ^-6/K, and they were in better agreement with the prediction of Kerner's model. To calculate the thermal conductivity of the composite with dual-sized reinforcements, an equivalent particle diameter was introduced to the effective medium approximation method. The predicted values agreed well the measured conductivity.