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Pidgeon process for producing metallic magnesium.
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An alloy of iron and silicon used to add silicon to steel and iron, d 5.4, insoluble in water. Small quantities of silicon deoxidize the iron, and larger amounts impart special properties.
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A solid alloy of iron and silicon. Used to add silicon to iron and steel. Ferric silicon is an odorless, crystalline solid metal. Ferric silicon is flammable and can react explosively with oxidizing materials. In the presence of moisture or water Ferric silicon may emit toxic and explosive fumes. Ferric silicon is used in magnesium processing.
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Flammable. Reacts with water or moisture in the air to form flammable hydrogen gas. The heat created by the reaction may be sufficient to ignite the hydrogen generated.
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Metals, such as Ferric silicon, are reducing agents and tend to react with oxidizing agents. Their reactivity is strongly influenced by their state of subdivision: in bulk they often resist chemical combination; in powdered form they may react very rapidly. Thus, as a bulk metal Ferric silicon is somewhat unreactive, but finely divided material may be pyrophoric. The metal reacts exothermically with compounds having active hydrogen atoms (such as acids and water) to form flammable hydrogen gas and caustic products. The reactions are less vigorous than the similar reactions of alkali metals, but the released heat can still ignite the released hydrogen. Materials in this group may react with azo/diazo compounds to form explosive products. These metals and the products of their corrosion by air and water can catalyze polymerization reactions in several classes of organic compounds; these polymerizations sometimes proceed rapidly or even explosively. Some metals in this group form explosive products with halogenated hydrocarbons.
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Ferrosilicon containing from 30 to 90% silicon is flammable and evolves gases in the presence of moisture.
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Exposure can cause irritation of eyes, nose and throat. Toxic if inhaled or ingested.
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Special Hazards of Combustion Products: Irritating vapors and toxic gases may be formed when involved in fire.
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This is a high-silicon master alloy used for makingsilicon steels, and for adding silicon to transformerirons and steels. It is made in the electricfurnace by fusing quartz or silica with iron turningsand carbon. Silicon is often added to steelsin combination alloys with deoxidizers or otheralloying elements. Ferrosilicon aluminum is amore effective deoxidizer for steel than aluminumalone. It is also used for adding silicon toaluminum casting alloys. The alloy serves as adeoxidizer, fluxes the slag inclusions, and alsocontrols the grain size of the steel.
Safety Profile
Moderate inhalation
hazard. Low skin toxicity. Reaction with
moisture releases hydrogen and acetylene
gases, whch then ignite; impurities in the
alloy may liberate such poisonous and
reactive gases as phosphine and arsine. Dry
mixtures with sodium hydroxide react
incandescently when water is added.
Reaction with acid, acid fumes, or oxidzing
materials can emit toxic fumes. Reaction hazards increase with decreasing particle
size.
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