THERMAL DIFFUSIVITY OF CAST Al-Cu ALLOYS

Abstract The regulations imposed to reduce fuel consumption by internal combustion engines and the corresponding reduction in CO2 emissions to the atmosphere has become more stringent. Industry has responded by designing smaller and lighter engines able to develop higher power outputs by increasing the temperature within their combustion chambers, although the higher temperatures may affect the mechanical and structural response of the materials, in such a way that conventional Al-Si alloys are reaching their limits. This work presents the results of studies conducted on a wide range of alloys to evaluate the dependence of their thermal diffusivity with respect to temperature, chemical composition and microstructure. The analyses show that thermal diffusivity can be enhanced by modifying their processing to achieve grain refining and precipitation coarsening. It is also found that thermal diffusivity is enhanced at higher temperatures.