STEEL

STEEL

1. CONCEPT: Steel is an alloy of iron with a quantity of carbon that it can vary between 0.03% and 1.075% by weight of its composition, depending on the grade. Steel is not the same as iron. Y Both materials should not be confused. Iron is a relatively hard metal and tenacious, with atomic diameter (dA) of 2.48 Å, with melting temperature of 1535 ° C and boiling point 2740 ° C.

2. HISTORY: The first artisans to work on iron, produced alloys that today would classify as wrought iron, this by a technique that involved heating a mass of iron ore and charcoal in a large furnace with forced draft, in this way it was reduced the ore to a spongy iron mass metallic filled with a scum of impurities metallic, along with charcoal ashes.

3. CHARACTERISTICS: Medium density: 7850 kg / m³ It can contract, dilate or melt, depending on the temperature. His point melting depends on the alloy and the percentages of alloying elements. Frequently, around 1,375 ° C. Boiling point: around 3,000 ° C. It is a very tenacious material, especially in used alloys for tools Is relatively ductile; It serves to make wires. Is malleable; can be transformed into sheets as thin as tin, between 0.5 and 0.12 mm thick.

4. STEEL TYPES

   • STEEL CORTEN: Corten Steel is a Steel common to that does not affect corrosion. It is an alloy of Steel with nickel, chromium, copper and phosphorus that, after a process alternative wetting and drying forms a very thin appearance oxide film reddish-purple. APPLICATIONS: It is used in the Industry cement, silos, hoppers, screeners, chimneys, pipes, coal washers, water tanks, oil, fuel oil, etc. Metal constructions, bridges, structures, building facades, doors metal, concrete mixers, cranes, excavator shovels. Railroad cars, truck chassis, swingarms, cisterns, semitrailers.
     • CHARACTERISTICS: it is a common steel that does not It affects corrosion. Its chemical composition (alloy steel with nickel, chrome, copper and phosphorus) causes its oxidation to have some special features that protect the piece against atmospheric corrosion. Hence this material has great value and oxidation has become voluntary and controlled
   • STAINLESS STEEL: It is called Stainless Steel a any type of alloy steel whose weight contains as minimum 10.50% Chrome, but not more than 1.20% of Carbon, with any other alloy element or without he. It contains chrome, nickel and other alloy elements, that keep it shiny and corrosion resistant to despite the action of moisture or acids and gases.
     • CHARACTERISTICS: Stainless steel presents excellent mechanical properties at room temperature in comparison with other materials, advantage to stand out in the sector of the construction because it allows reducing the weight per m² or dimensions of the constructive elements. His good ductility, its elasticity and hardness combined with good resistance to wear (rubbing, abrasion, shock, elasticity ...) allow to use the stainless steel in a wide range of projects.

5. TYPES OF OVENS

   • Martin-Siemens oven: The oven Martin-Siemens is an oven of glare. The hearth heats up outwardly and the pig iron and the scrap inclined towards a hole exit. The capacity of these ovens is very variable: there are up to 250 tons. The vault is brick silica refractory. Outside cold air circulates to cool.
   • Basic oxygen oven It is an oven with pear shape that can produce some 300 tons of steel in 45 minutes. Is very similar to Bessemer with the great difference to this oven instead of inject air under pressure oxygen is injected under pressure, so that the temperature than in the Bessemer and in a Very short time. The oven load It is made up of 75% pig iron coming from the blast furnace and the rest is scrap and lime.
   • Electric oven This is the most versatile oven for manufacture steel, can reach a temperature of 1930 ° C, temperature that can be controlled electrically. There are electric arc furnaces that can contain Up to 270 tons of molten material. To melt 115 tons are required approximately three hours and 50,000 Kwh of power Also in these ovens are injects pure oxygen through a spear. When applied electric current, arc formation between giant electrodes produces intense heat.

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