Specific heat, thermal diffusivity, and thermal conductivity of Ag–Si alloys within a wide temperature range of 293–823 K

Abstract

The laser flash method was employed to explore the heat transfer behaviors of Ag-x at.% Si (where x = 0, 5, 11, 25, 50, 75 and 100) alloys over a wide temperature range from 293 to 823 K. The temperature dependency of specific heat and thermal diffusivity were determined by a differential scanning calorimeter and laser flash equipment. Accordingly, the thermal conductivity of Ag–Si alloys was derived. It is found that the thermal conductivity decreases with increasing temperature. At a certain temperature, there is a sharp decline of thermal conductivity with the rising Si content before it reaches the eutectic composition. The decreasing rate of conductivity with rising Si content reduces when Si content is larger than 11%. The microstructures of Ag–Si alloys reveal that the abnormal thermal conductivity at eutectic composition may be caused by the large amount of phase boundaries.