Determination of thermal diffusivity and thermal conductivity of Mg–Al alloys

The thermal diffusivity and thermal conductivity of magnesium–aluminium alloys AM20, AM50 and AM60 were investigated in the temperature range from 20 to 300 °C. The thermal diffusivity of AM20 increases with increasing temperature upto 160 °C, above this temperature the increase is less marked. The change in the slope of the temperature variation of the thermal diffusivity is probably caused by a reduction of the amount of Mg17Al12 phase. The values of the thermal diffusivity and of the thermal conductivity of the solid solution are lower than those obtained when the alloys contain two phases. The measured values are compared with those calculated by transformed Nordheim rule.