STUDY THE EFFECT OF GERMANIUM AND SILICON ADDITIONS ON THERMAL PROPERTIES AND MICROSTRUCTURE OF PURE ALUMINUM

Abstract

In this study an experimental work has been conducted to show the effect of Ge and Si additions on the micro structure and thermal properties of pure Al, as the specific heat at constant volume (Cv), thermal conductivity (k), and thermal diffusivity .Six samples have been casted with different addition percentages of Ge and Si (10,20,30%).The results shows as the Ge addition percentage is increased, the alloy density is increased by (29.34%), the thermal conductivity is decreased by (20.85%),the specific heat is decreased by (19.4%) and thermal diffusivity is decreased by (24.1%). But as the Si addition percentage is increased cause decreasing the alloy density by (4.21%), the thermal conductivity by (7.3%),the specific heat by (6.7%) and increasing the thermal diffusivity by (3.7%).Through this study it was found that the best addition is 30% (Si) addition percentage for pure Al gives highest thermal properties (Cv,k, ) compared with the same addition percentage of (Ge) .and from micro structure , it was found the distribution of (Si) particle through (Al) . phase , for the (Ge) particle it was found the a glomeration of (Ge) particle is because the weak of the wetting property of (Ge) comparing with the (Si) particles