Phosphor alterative for hypereutectic aluminum-silicon alloy

Abstract

The invention relates to a phosphorus modifier of hyper eutectic aluminium silicon alloy. The invention is characterized in that the modifier comprises components according to the following mass percent: 1 percent to 30 percent of powder phosphor, 1 percent to 50 percent of aluminum powder, 5 percent to 40 percent of chloride, and 1 percent to 20 percent of fluoride, after the process of ball milling and homogenizing, the components are pressed into blocks as block shaped modifier. The modifier of the invention is suitable for the modifying treatment of the hyper eutectic aluminium silicon alloy, the key problem during the production of the hyper eutectic aluminium silicon alloy is magnificently solved, the fume discharged when the phosphorus modifier is pressed in is obviously reduced, the charging time is shortened, the slag amount is reduced; the absorption rate of the phosphorus modifier is enhanced, the raw material consumption is reduced; the pollution is reduced, the waste discharging is reduced; the production is stable, the operation process is simplified, the adding temperature is reduced, and working environment is improved. The invention has good social and economic benefits, and good promotion and application value.

Description

technical field [0001] The invention relates to a phosphorus modifier for a hypereutectic aluminum-silicon alloy. Background technique [0002] Hypereutectic Al-Si alloy is currently the most potential casting aluminum alloy. Due to the small linear expansion coefficient, light density, good fluidity, thermal crack resistance, excellent wear resistance and corrosion resistance, hypereutectic aluminum-silicon alloy is used in the manufacture of pistons for internal combustion engines and swash plates for automotive swash plate compressors. High quality material for the piston. However, the primary Si phase in the original casting structure of the alloy is coarse, in the shape of plate, polygon, and five-lobed star, which severely splits the matrix structure, which not only seriously reduces the mechanical properties of the alloy, but also deteriorates the casting properties of the alloy, affecting The practical progress of the alloy. [0003] Phosphorus modification is by ...

AI Technical Summary

Problems solved by technology

[0006] (1) Red phosphorus composite modificator, due to the low ignition point and sublimation temperature of phosphorus, there is a potential safety hazard in the transportation and storage process; the reaction is violent during the addition process, producing toxic phosphorus pentoxide gas, which pollutes the environment; the absorption rate of phosphorus is low, And it is difficult to control; after pressing into the melt after briquetting, although the reaction is relatively stable, a large amount of smoke will still be emitted, resulting in low absorption rate and large pollution

[0007] (2) Phosphate-salt compound modificator also produces harmful gas and causes serious environmental pollution; produces a large amount of reaction slag, corrodes the furnace lining, and increases aluminum consumption; the absorption rate of phosphorus is limited by the process conditions, the metamorphic effect is unstable, and the scrap rate is high

[0008] (3) Phosphorus-containing master alloys, such as Cu-P-(X), have a high melting point and are difficult to melt after being added; they are dense and easy to segregate; they are not suitable for static furnace production (domestic production status), only suitable for induction furnace production; the process is long , high energy consumption; increasing the content of elements other than Cu and P in the alloy limits the grade of the alloy used

[0009] (4) Using the highly toxic drug AlP as raw material, there are certain safety problems in the production process

[0010] (5) The adding temperature of the modificator is relatively high, usually above 800°C, resulting in high energy consumption

Some people in China use the highly toxic drug AlP as a raw material to develop Al-P master alloys containing AlP prefabricated crystal nuclei. There are certain safety problems in the production process.