Composite modifying-refining agent for hypoeutectic cast aluminium-silicon alloy and treatment process

Abstract

The invention relates to a high efficiency compounded refiner for hypoeutectic aluminum-silicon alloy and the method of application. It contains 10-30wt% NaCl, 10-15wt% KCl, 10-20wt% sodium fluoride, 1-30wt% potassium fluoborate, and 1-20wt% potassium fluotitanate, 1-20wt% strontium carbonate, 1-15wt% cerium fluoride, 5-20wt% granular lanthanum abundant mixed rare earths and 1-5% heachloroethane. After taking the process of heating, dehydrating, mixing according to the ratio to equal, pressing to molding, it could be sealed to use. The technology includes the following steps: after the magnesium alloy melting in crucible, heating to 720-740 degree centigrade and removing the slag, standing for 3-5 minutes, pressing the refiner into alloy liquid to take refining process for 5-10 minutes, standing for 5-10 minutes after process to gain hypoeutectic aluminum-silicon alloy melt. The invention simplifies melt process technology, lowers cost and improves the capability of alloy.

Description

Technical field:

[0001] The invention relates to a modification and refinement technology of a hypoeutectic cast aluminum-silicon alloy. technical background:

[0002] As an important part of cast Al-Si alloy materials, hypoeutectic Al-Si alloy has been widely used in aerospace, automobiles and other transportation machinery because of its excellent casting properties, good mechanical properties and physical and chemical properties. Since the mechanical properties of the hypoeutectic Al-Si alloy are closely related to the shape and size of the eutectic silicon in the alloy structure, generally speaking, the smaller the size and the rounder the shape of the eutectic silicon in the alloy structure, the higher the mechanical properties of the alloy. Considering that when the alloy is not modified, the eutectic silicon in the alloy structure mainly appears in the form of coarse needle flakes, which severely splits the matrix, resulting in a decrease in the mechanical properties ...