This study investigates the effect of Mg addition on the thermal properties and precipitation behavior of Al-5.8Zn alloy. The Al-5.8Zn-xMg alloy underwent gravity casting and was subsequently treated with a solution at 480°C for 6 h, followed by artificially aged at 120 °C. The precipitation sequence of MgZn2 phases in the Al-Zn system was analyzed by DSC. The thermal diffusivity, thermal conductivity, specific heat, and thermal expansion of the alloy were also measured. The results showed that Mg addition decreased the thermal diffusivity and conductivity of the alloy at room temperature while simultaneously enhancing the strength with prolonged aging time.
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