Cast aluminum alloy high in thermal conductivity

[0019] Example 1

[0020] A high thermal conductivity cast aluminum alloy of the present invention has the weight percentages of each group as follows, silicon: 4.0%, iron: 3.0%, copper: 0.4%, magnesium: 0.15%, manganese: 0.3%, nickel: 0.6%, tin: 0.1%, impurity: 0.1%, the rest is aluminum.

[0021] Add raw materials according to the ratio for smelting, first preheat the furnace at 400-450°C for 20 minutes, and purge with inert gas, then add pure aluminum ingots for melting, when the temperature of pure aluminum industry reaches 800°C, keep the temperature for 20 minutes , use pure aluminum to fully melt, then lower the temperature of the furnace to 760 ° C, then add pure silicon, keep the temperature for 20 minutes, after the silicon is melted, continue to stir for 10 minutes, cool down, when the temperature of the furnace drops to 700 ° C, then add the remaining intermediate alloy After the melting is complete, let it stand still, and finally add magnesium, after the melting is complete, continue to stir for 6 minutes, remove the scum, add refining agent at 700 ° C for refining, stir for 15 minutes, carry out the composition analysis before the furnace, and detect the composition content of the alloy , for the melt with unqualified component content, it can reach the qualified range by feeding or diluting. Cool the alloy melt with qualified composition content to 670°C, use inert gas to degas and remove slag, analyze the composition before the furnace, die-cast after passing, and perform aging treatment under the condition of 120°C, and the aging time is 5 hours.

[0022] The uniaxial tensile strength of the obtained aluminum alloy is 228MPa, the yield stress is 131MPa, the elongation is 6.0mm, the hardness is 80BHN, the shear strength is 122MPa, the fatigue strength is 117MPa, the elastic modulus is 7.1GPa, and the thermal conductivity is 171W/mK .

[0023] Example 2

[0024] A high thermal conductivity cast aluminum alloy of the present invention has the weight percentages of each group as follows, silicon: 6.5%, iron: 1.0%, copper: 1.0%, magnesium: 0.05%, manganese: 0.4%, nickel: 0.4%, tin: 0.2%, impurities: 0.15%, the rest is aluminum.

[0025] According to the ratio of adding raw materials for smelting, first preheat the furnace at 450°C for 30 minutes, and purging with inert gas, then add pure aluminum ingots for melting, when the temperature of pure aluminum industry reaches 830°C, keep the temperature for 30 minutes, use The pure aluminum must be fully melted, then lower the temperature of the furnace to 790°C, then add pure silicon, keep the temperature for 30 minutes, after the silicon melts, continue to stir for 15 minutes, then cool down, when the temperature of the furnace drops to 740°C, add the remaining intermediate alloy and melt After it is complete, let it stand still, and finally add magnesium. After the melting is complete, continue to stir for 8 minutes to remove scum, add refining agent at 740°C for refining, and stir for 20 minutes. The melt with unqualified component content reaches the qualified range by feeding or diluting. Cool the alloy melt with qualified composition content to 700°C, use inert gas to degas and remove slag, analyze the composition before the furnace, die-cast after passing, and carry out aging treatment at 150°C, and the aging time is 10 hours.

[0026] The uniaxial tensile strength of the obtained aluminum alloy is 230MPa, the yield stress is 142MPa, the elongation is 6.5mm, the hardness can reach 85BHN, the shear strength is 132MPa, the fatigue strength is 124MPa, the elastic modulus is 7.4GPa, and the thermal conductivity is 185W/mK.

[0027] Example 3

[0028] A high thermal conductivity cast aluminum alloy of the present invention has the weight percentages of each group as follows, silicon: 5.0%, iron: 2.0%, copper: 0.6%, magnesium: 0.1%, manganese: 0.35%, nickel: 0.5%, tin: 0.15%, impurity: 0.2%, the rest is aluminum.

[0029] According to the ratio of adding raw materials for smelting, first preheat the furnace at 420 ° C for 25 minutes, and purging with inert gas, then add pure aluminum ingots to melt, when the temperature of pure aluminum industry reaches 810 ° C, keep the temperature for 25 minutes, use The pure aluminum must be fully melted, then lower the temperature of the furnace to 770°C, then add pure silicon, keep the temperature for 25 minutes, after the silicon melts, continue to stir for 12 minutes, then cool down, when the temperature of the furnace drops to 720°C, add the remaining intermediate alloy and melt After it is complete, let it stand still, and finally add magnesium. After the melting is complete, continue to stir for 7 minutes to remove scum, add refining agent at 710°C for refining, and stir for 17 minutes. The melt with unqualified component content reaches the qualified range by feeding or diluting. Cool the alloy melt with qualified composition content to 690°C, use inert gas to degas and remove slag, analyze the composition before the furnace, die-cast after passing, and perform aging treatment at 140°C, and the aging time is 8 hours.

[0030] The uniaxial tensile strength of the obtained aluminum alloy is 235MPa, the yield stress is 138MPa, the elongation is 7.2%, the hardness can reach 90BHN, the shear strength is 128MPa, the fatigue strength is 121MPa, the elastic modulus is 7.1GPa, and the thermal conductivity is 178W/mK.