7075 aluminum alloy was prepared by permanent mold casting（PMC）

liquid squeeze casting（LSC）and semi-solid squeeze casting（SSC）methods.The effects of different casting processes on the thermal conductivity and mechanical properties of 7075 aluminum alloy were investigated.The results indicate that the grains of the PMC are coarse

and dendrite segregation occurs to reduce the plastic toughness.The tensile strength and elongation are 121 MPa and 2.78%

respectively.However

the coarse grains exhibit a wide heat conduction path

lower electron scattering probability

long mean free path and relatively high thermal conductivity

which reaches139.67 W/（m·K）.The tensile strength and elongation of the LSC refined grains are 239 MPa and 5.75%

respectively

while fine grains and more dendritic arms lead to the higher electronscattering

with the lowest thermal conductivity

which is 120.94 W/（m·K）.SSC grains are compact fine and round

with the highest tensile strength and elongation of 248 MPa and 7.46%

respectively

and the thermal conductivity is 126.07 W/（m·K）.