High-strength high heat conductivity thin-walled die casting aluminum alloy and preparation method thereof

Abstract

The invention relates to a high-strength high heat conductivity thin-walled die casting aluminum alloy and a preparation method thereof. The alloy comprises the following elements in percentage by weight: 12-14wt% of Si, 0.05-3wt% of Cu, 0.40-0.80wt% of Fe, 0.00-0.05wt% of Mg, less than 0.05wt% of other impurities and the balance of Al. Compared with the prior art, by strictly controlling the total amount of Cu and Mg within 0.05-3wt% and then carrying out thermal treatment at 175 DEG C for 4h, Cu and Mg elements will not dissolved in a substrate, so that a micro dispersive CuAl2 second phaseand Mg17Al12 second phase are formed in the material. Fe element can prevent the material from being stuck to a die, so that a thin-walled product is casted more effectively. Meanwhile, the second phases can enhance the strength of the material effectively, so that the tensile strength of the material is greater than 300MPa, the yield strength is greater than 150MPa and the ductility is 8-10%.

Description

technical field [0001] The invention relates to an aluminum alloy, in particular to a thin-wall die-casting aluminum alloy with high strength and high thermal conductivity and a preparation method thereof. Background technique [0002] Silver is the best thermal conductor, followed by copper, gold and aluminum. However, because gold and silver are too expensive, they cannot be used on a large scale. In contrast, the heat dissipation effect of copper is very ideal, but copper has a big disadvantage: copper has high deformation resistance and is difficult to extrude into profiles with complex sections. If it is manufactured by precision casting, welding or machining technology, it will cause Processing difficulty is big, processing cost is high etc. problem. Therefore, the usual heat sinks are mostly extruded from aluminum alloy. [0003] Both 1××× alloys and 6××× alloys have high thermal conductivity. However, due to the requirements of subsequent processing, the heat sin...

AI Technical Summary

Problems solved by technology

However, because gold and silver are too expensive, they cannot be used on a large scale

In contrast, the heat dissipation effect of copper is very ideal, but copper has a big disadvantage: copper has high deformation resistance and is difficult to extrude into profiles with complex cross-sections. If it is manufactured by precision casting, welding or machining technology, it will cause Difficulty in processing, high processing cost, etc.

However, grain refinement will increase the number of metamorphic crystal nuclei, making it more difficult for electrons to pass through, and weaken the electrical and thermal conductivity of aluminum alloys; more alloying elements will affect the uniformity and purity of the body structure. Therefore, in addition to producing In addition to the second phase effect, almost all alloying elements will reduce the thermal conductivity of the alloy

[0006] By adding about 10% Si element to the aluminum alloy, the casting fluidity of the aluminum alloy material can be effectively improved, and at the same time, the high thermal conductivity of the aluminum alloy material can be ensured, but the strength of this aluminum alloy material is still low

Images