Why So Many Types of Steel?
Essentially, steel is an alloy of iron and carbon with some other metals mixed in. Depending on the type of steel, aluminium, chromium, nickel, cobalt, tungsten and molybdenum may be present in small quantities. Steel is hard, ductile, malleable and solid. Numerous things that you use every day are made at least partially from some type of steel, including kitchen knives, pots and pans, automobile frames, tools, furniture, bridges and buildings.
High carbon steel contains a higher percentage of carbon than other types of steel. High carbon steel is often used to make cutting tools such as knives, axes, scissors and swords. It is also used in woodworking tools. The high percentage of carbon makes this type of steel both harder and more brittle than some other types of steel. High carbon steel tools can be sharpened easily but they are not hard enough to cut other hard materials such as metal or stone.
Mild steelis so-called because it contains only a low percentage of carbon. Mild steel is very versatile and is used in the manufacture of a wide variety of items, including sheet metal roofs, automobile frames, construction panels and large storage containers. Mild steel has also replaced wrought iron as the metal used in rail road tracks.
Medium carbon steel is in between high carbon steel and mild steel in terms of carbon content. Medium carbon steel has more hardness than mild steel and more tensile strength than high carbon steel, making it suitable for use in springs, tool frames and automotive components.
Stainless steel is especially corrosion resistant due to the 11 per cent chromium and small amount of nickel present in the alloy. Steel is more rust resistant than iron anyway, but stainless is the most resistant, not only to rust, but also to scratches and other types of corrosion. Stainless steel is a very common material for jewellery, watches, surgical equipment, cooking utensils and kitchen appliances.
High speed steel includes chromium, cobalt, tungsten or molybdenum in the alloy. High speed steel is especially tough and can be used to cut other metals and types of steel. Drills, power saws and other tools are made from high speed steel. The exact toughness and uses of high speed steel depend on the particular metal and percentage in the alloy.
Cobalt steel is very similar to high speed steel and contains a high amount of cobalt. Cobalt steel is not quite as hard as high speed steel, but it is often used for drilling. Cobalt steel drill bits have a slight brown tint.
Nickel chromium steel has the unique property of being shock resistant. Combined with its strength, this attribute makes nickel chromium steel ideal for use in armour plating.
Aluminium steel is smooth and fairly strong. Steel furniture is typically made from aluminium steel.
Chromium steel, like stainless steel is very corrosion resistant. Automobile and airplane components are often manufactured using chromium steel.
