Steelmaking Raw Materials: Deoxidizer, inoculant and ferroalloy manufacturer

Anyang Guoxiang Metallurgical Materials Co., Ltd. can produce and process ferrosilicon, calcium silicon alloy, silicon aluminum alloy, silicon carbide, silicon carbide powder, nodulizer for ductile iron, inoculant, pipe mold powder, and recarburizer for steelmaking and foundry.

Raw materials for steelmaking are divided into main raw materials, auxiliary raw materials (Graphitized Recarburizer, etc.) and various ferroalloys

Ferroalloys/Deoxidizer

Ferroalloys are generally used as deoxidizers: to remove oxygen in molten steel during steelmaking. Some ferroalloys can also remove other impurities in steel such as sulfur and nitrogen.
As steelmaking deoxidizers, the most widely used are silicomanganese, ferromanganese and ferrosilicon. Strong deoxidizers are aluminum (aluminum iron), silicon calcium, silicon zirconium, etc. (see steel deoxidation reaction). Common varieties used as alloy additives are: ferromanganese, ferrochrome, ferrosilicon, ferro tungsten, ferromolybdenum, ferrovanadium, ferro-titanium, ferronickel, niobium (tantalum) iron, rare earth ferroalloys, ferroboron, ferrophosphorus, etc. Various ferroalloys are based on the needs of steelmaking, and many grades are specified according to the content of alloying elements or the level of carbon content, and the content of impurities is strictly limited.
There are many kinds of ferroalloys, and there are many classification methods. Generally, they are classified according to the following methods:
(1) According to the main elements of ferroalloys, there are mainly silicon, manganese, chromium, vanadium, titanium, tungsten, molybdenum and other series of ferrous alloys.
(2) According to the classification of carbon content in ferroalloys, there are high-carbon, medium-carbon, low-carbon, micro-carbon, ultra-fine carbon and other varieties.
(3) Multi-element iron alloys containing two or more alloying elements, the main varieties are silicon aluminum alloy, silicon calcium alloy, manganese silicon aluminum alloy, silicon calcium aluminum alloy, silicon barium calcium alloy, etc.
(4) Classified by production method: there are blast furnace ferroalloys, electric furnace ferroalloys, out-of-furnace (metal thermal) ferroalloys, vacuum solid reduction ferroalloys, electrolytic ferroalloys, in addition to special ferroalloys such as oxide briquettes and heating ferroalloys.
Ferrosilicon, ferromanganese, silicomanganese, ferrochromium, ferro tungsten, ferrovanadium, ferronickel, ferromolybdenum, ferro-titanium, rare earth magnesium silicon, rare earth ferrosilicon, silicon calcium alloy, silicon barium alloy, silicon aluminum alloy, tantalum niobium, Phosphorus iron, boron iron, etc.

Nodulizer

The nodulizer is certain metals or alloys added to the molten iron to obtain spheroidal graphite cast iron. The spheroidizing agent commonly used in my country is rare earth magnesium ferrosilicon alloy. Most foreign countries use magnesium-based spheroidizing agents (pure magnesium and magnesium alloy). A few countries use calcium-based spheroidizing agents. The spheroidal graphite in spheroidal graphite cast iron is formed by spheroidization of molten cast iron, which makes it much stronger than gray cast iron and better toughness than malleable cast iron, while maintaining a series of advantages of gray cast iron. However, the "spheroidizing agent" used in nodular cast iron casting can increase the tendency of the weld to produce "white mouth" and hardened structure, and induce cracks in the weld and the heat-affected zone (especially the fusion zone). Therefore, the weldability of nodular cast iron is worse than that of gray cast iron. Various grades of rare earth silicon-magnesium alloy spheroidizing agent used for ductile cast iron. After the addition of molten iron, it can be used for spheroidization, desulfurization and degassing, and can improve the purity of the cast water. Melting point impurities play a role in generating low melting point and do not melt in iron compounds to eliminate these impurities, which can prevent interfering elements from destroying spheroidization.

Inoculant

Inoculant is a kind of inoculant that can promote graphitization, reduce the tendency of white mouth, improve the shape and distribution of graphite, increase the number of eutectic clusters, and refine the matrix structure. It has a short period of time (about 5-8 minutes) after inoculation treatment. good effect. It is mainly suitable for general conditions of various situations or instantaneous incubation in the later stage. Inoculation treatment refers to adding a small amount of other substances to the liquid metal during the solidification process to promote nucleation, inhibit growth, and achieve the purpose of grain refinement. Traditionally, adding additives to cast iron is called inoculation treatment; adding additives to non-ferrous alloys is called modification treatment. Essentially, the inoculation treatment mainly affects nucleation and promotes the freeing of crystal grains; while the metamorphism treatment changes the growth mechanism of crystals (inhibits growth), thereby affecting the crystal morphology.
Effect
The mechanical properties of gray cast iron depend to a large extent on its microstructure. Gray cast iron that has not been inoculated has unstable microstructure, low mechanical properties, and white holes are prone to appear in the thin wall of the casting. In order to ensure the consistency of casting quality, inoculation treatment is essential.
The inoculant used in the inoculation treatment of cast iron is added in a small amount, which has little effect on the chemical composition of cast iron, but has a great effect on its microstructure, so it can improve the mechanical properties of gray cast iron and has obvious effects on its physical properties. Good inoculation treatment has the following effects:
◆Eliminate or reduce the tendency of white mouth;
◆Avoid cold tissue;
◆Reduce the wall thickness sensitivity of iron castings, so that the difference in microstructure between thin and thick sections of castings is small, and the difference in hardness is also small;
◆Conducive to the nucleation of eutectic clusters and increase the number of eutectic clusters;
◆The form of graphite in cast iron is mainly fine and evenly distributed A-type graphite, thereby improving the mechanical properties of cast iron.
The cast iron with good inoculation has better fluidity, the shrinkage of the casting is reduced, the processing performance is improved, and the residual stress is reduced.
How to use
1. Pour bag inoculation: add the inoculant into the bag, then flush into the molten iron to melt it evenly, and then pour.
2. The added amount is about 1.0-1.8% of the weight of the molten iron.