The Al-Si alloy with high thermal conductivity was prepared by the metal mold casting

and the effects of heat treatment parameters（solution temperature）on the thermal conductivity and mechanical properties of the alloy were investigated by a single test method through optical microscopy（OM）and scanning electron microscopy（SEM）

laser thermal conductivity analyzer

tensile test and other characterization methods to analyze comparatively the microstructure

tensile strength

elongation and thermal conductivity of the alloy before and after heat treatment.The results reveal that thermal conductivity of the alloy reach 153.1 W/（m·K）

the shape of the primaryα-Al phase becomes regular with the increase of the solution temperature after solution treatment

and the eutectic silicon begins to break and spheroidize from irregular lamellar.The thermal conductivity of the alloy is increases first and then decreased.At 540℃

the maximum value is 190.8 W/（m·K）

which is increased by 24.6%

while it is decreased sharply at 560℃.The tensile strength is increased from 188.35 MPa at the as-cast state to 255.74 MPa at 540℃

and the elongation is increased from 4.5% to 14.41%.