Preparation method of high-thermal-conductivity AlSi alloy

Abstract

The invention relates to a preparation method of a high-thermal-conductivity AlSi alloy. The preparation method comprises the following steps: preparing materials, wherein raw materials are prepared according to the composition proportion of the alloy; melting, wherein a pure aluminum ingot is placed in a smelting furnace to be heated and melted to form molten aluminum; transferring molten aluminum in the smelting furnace into an alloying furnace, increasing the temperature to 760-780 DEG C, and adding an Al-50Si intermediate alloy; after the molten aluminum is completely melted, uniformly stirring for 10-30 minutes, and performing modification treatment by keeping the temperature unchanged in the stirring process: removing scum on the surface of the molten aluminum, increasing the temperature of the molten aluminum to 770 DEG C, and adding an Al-10Sr intermediate alloy modifier; conducting refining treatment, wherein the temperature of molten aluminum in the alloying furnace is controlled to be 770 DEG C, and an Al-3Sc intermediate alloy is added; and conducting heat treatment, wherein the temperature is gradually increased to 240-255 DEG C within one hour, heat preservation is conducted for 0.5 hour, then the temperature is gradually increased to 335-350 DEG C within one hour, heat preservation is conducted for 2 hours, and then furnace cooling is conducted to the room temperature. The aluminum-silicon alloy which is excellent in comprehensive performance and high in heat conductivity is prepared by carrying out process integration innovation improvement on the aspects of melt refining, modification refining, artificial aging heat treatment and the like, and the aluminum-silicon alloy has important application and popularization value.

Description

technical field [0001] The invention relates to a method for preparing an AlSi alloy with high thermal conductivity, and relates to the technical field of material manufacturing. Background technique [0002] Aluminum alloy has many characteristics such as low density, high specific strength, good electrical / thermal conductivity, and good formability, and is widely used in the fields of automobiles, electronics, and communications. High thermal conductivity is a special requirement for aluminum alloys in many heat exchange fields. Generally, the thermal conductivity of pure aluminum at room temperature is high, about 238w / (mK), and the thermal conductivity of deformed aluminum alloys such as 6063 is also as high as 209w / (mK), but with the increase of alloying elements, the thermal conductivity of aluminum alloys The thermal conductivity decreases gradually, and the effects of different elements on the thermal conductivity of the alloy are quite different. The physical natu...

AI Technical Summary

Problems solved by technology

However, these measures can only make the thermal conductivity of aluminum-silicon alloy reach about 175W / (m.k), which is difficult to meet the high thermal conductivity requirement of over 195W / (m.k); in addition, because B element is extremely easy to oxidize, oxide impurities are produced And specific gravity segregation, and then the thermal conductivity of the product cannot be maintained stably, which is not conducive to the precision die-casting of the product

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