Low magnesium spheroidizing line: Ductile iron castings are widely used in the fields of automobile, machine and equipment manufacturing. There are various types of spheroidizing agents used in the production of ductile iron. At present, master alloys containing magnesium and rare earth are mainly used as spheroidizing wires in production. There are also some other spheroidized wires, such as pure magnesium, mechanical mixtures containing magnesium. The selection of spheroidizing line and spheroidizing treatment method mainly depends on production conditions, casting performance, etc. The main chemical components of the spheroidized wire are Mg5~10%; Re0~2%; Si0~10%, and the balance is iron. The composition is Mg5-9%, Re0.5-3%, Ca3.5-5.0%, Ba1.5-4.5%, Si35-50%, Bi0.5-4.5%, and the rest is iron. The spheroidizing line contains a large amount of metallic magnesium, which seriously restricts the production of low silicon ductile iron.

The mixture of metallic magnesium particles and iron-silicon alloy is placed at the bottom of the tundish. In order to improve the absorption rate of metallic magnesium and prevent metal splashing, it is covered with scrap steel, and then molten iron is poured for spheroidization. Compared with the low magnesium spheroidizing agent, the size of the metallic magnesium particles in this mixture is 0.05~0.145mm and the size of the iron-silicon alloy is 0.05~1.0mm. A mixture of metallic magnesium powder and iron-silicon alloy is used for spheroidization treatment. When metallic magnesium is added to the molten iron, along with the increase in silicon content, the silicon content in the mixture exceeds 10 to 20 times the amount of metallic magnesium added. After spheroidization, If the silicon content of molten iron exceeds 1.0%, low silicon (Si≤0.6%) high-strength cast iron cannot be obtained. In addition, the spheroidized mixture only contains 9% metallic magnesium, which greatly increases the amount of spheroidized mixture and will also cause the molten iron to cool down rapidly.

Advantages and Benefits

Spheroidized high magnesium cored wire is a spherical material, which has a larger contact area with other materials during use, which increases the reaction rate. This kind of cored wire has a higher magnesium content and has better heat dissipation. When used in gradual castings, it can improve its performance advantages. So what are the advantages of spheroidized high magnesium cored wire?

1. It is conducive to adjusting and controlling the content of easily oxidized elements and trace elements, which can greatly increase the alloy yield, reduce smelting costs, shorten smelting time, and strictly control the composition.

2. It plays the role of purifying molten steel and partially changing the nature and form of inclusions, improving the quality of molten steel and improving the casting state.

3. There are two types of cored wires: internally drawn type and external type. The mechanical equipment required for wire feeding is simple and reliable, and takes up less space. In particular, the internally drawn cored wire is more suitable for use in narrow places.

With the rapid development of production technology, the application fields of spheroidized high-magnesium core-covered wires have gradually expanded, and they have good application effects in the aerospace industry, motorcycle industry and other areas.