Ultra-long-acting dual modification method for hypereutectic aluminum-silicon alloy

Abstract

The invention discloses an ultra-long-acting dual modification method for hypereutectic aluminum-silicon alloy. The method specifically comprises the following steps that 1, preparation is performed,specifically, the hypereutectic aluminum-silicon alloy is prepared; 2, villiaumite weight and carbon powder weight are prepared according to the total weight of the aluminum-silicon alloy, and in theformula, (1) the mass ratio of Si / (Ti + Zr + B + C) is larger than or equal to 2 and smaller than or equal to 5; (2), the molar ratio of Ti to Zr to B to C is 1: 1: 2: 2; 3, the prepared aluminum andsilicon materials are added into an intermediate frequency reaction furnace for melting, then the prepared potassium fluoborate is added for reaction, potassium fluotitanate is added for reaction, graphene is added for reaction, potassium fluozirconate is added for reaction after molten aluminum is heated, residual liquid villiaumite is poured out after the reaction is finished, and then heating and heat preservation are performed; and 4, the molten aluminum in the intermediate frequency furnace is poured into a transfer ladle, then the molten aluminum is poured into an ingot furnace, and an aluminum alloy ingot is cast after the molten aluminum is cooled and argon is removed.

Description

technical field [0001] The invention relates to the technical field of modification methods for aluminum alloy materials, in particular to a long-term double modification method for hypereutectic aluminum-silicon alloys. Background technique [0002] Hypereutectic aluminum-silicon alloys have very good high-temperature mechanical properties, good wear resistance, good volume stability, and high temperature resistance. They are widely used in automotive engine pistons, petroleum industry and other industries that require lightweight and wear-resistant requirements. and other important industrial fields. Since the content of silicon in the hypereutectic aluminum-silicon system exceeds the eutectic point of the alloy, there are a large number of acicular or plate-like eutectic silicon structures and a large number of massive primary silicon structures in the micro-cast structure of the alloy. , if no modification treatment is carried out, the massive primary silicon particles ...

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Problems solved by technology

[0005] The existing process Al-Si alloy modification technology is mainly to add metamorphic elements in the alloy as the main technical means, among which the metamorphic primary silicon is mainly formed after adding P element to the aluminum liquid, forming AlP in the structure, and the primary silicon is formed in the structure during the solidification process. AlP is the crystal nucleus solidified so as to wait for the primary crystal silicon of fine particles. To achieve double modification, it is necessary to add elements such as Na, Sr, Ba, Te, Sb, S, Y, Ca, Bi, As, Ce, Nd, RE, etc. , but because P element reacts with most elements, it cannot achieve double metamorphism, or although it does not react with elements such as S, Ce, Nd, Y, RE, etc., it will weaken each other in the process of joint metamorphism, resulting in the need A large amount of metamorphic elements is added, the metamorphic effect is average, and the effective time of metamorphism is short, it is difficult to exceed 10 hours to achieve the initial metamorphic effect; and almost all metamorphic treatment methods that rely on adding metamorphic elements are re-melted, due to metamorphic elements The metamorphic effect will be weakened due to burning, segregation and other reasons, and a certain amount of metamorphic elements need to be added again to supplement, which causes quality fluctuations and waste

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