Steel is an alloy of iron (Fe) and some other element, usually carbon (C). The word steel is used most commonly for iron alloys with a limited carbon content. Steel is one of the most important materials in the world, found in everything from cars and bridges to ships, tools and kitchen appliances. It is an essential component of modern infrastructure and industry, and is used in a wide variety of forms, both natural and processed.
The classification of steels can be broadly divided into three main types; plate, sheet and bar. Plate is available in both hot rolled and cold rolled varieties, while sheet and bar can also be divided into hot and cold rolled.
Hot-rolled steel is formed by rolling a slab of steel through special rolls to form the desired shape, while cold-rolled steel is passed through special rolls at room temperature, which is then placed in an annealing furnace and heat treated at a controlled temperature. This can give the steel the desired strength and hardness. Both cold and hot rolled steels can be further processed to improve their properties, such as through pickling or coating.
Carbon steel is a common type of steel that is made from an alloy of iron and carbon, as well as other elements. It is available in both hot and cold rolled forms and is generally used for products that require high strength, such as wire rope and suspension bridges. High carbon steel which contains 0.6% - 1.4% carbon is commonly used for tools and machine components, such as saw blades and hand tools.
Alloy steels are steels that contain alloying elements, such as copper, nickel, chromium and molybdenum, as well as small amounts of other elements to improve the strength, corrosion resistance and formability of the steel. Alloy steels are often used in applications where higher strength and wear resistance is needed, such as in aircraft frames, and motor components.
Stainless steel is a type of steel that contains at least 10.5% of chromium content to resist corrosion. It is available in different forms such as ferritic, austenitic and martensitic, and is generally used in applications that require corrosion resistance, such as in kitchen appliances and cutlery.
Tool steel is a type of alloy steel that is designed to retain its shape under extreme temperatures, and can withstand high impact forces. Tool steels are characterized by a very high hardness, making them ideal for cutting tools, such as drill bits, saw blades and other cutting tools used for metalworking.
Finally, high speed steel (HSS) is a special type of alloy steel that contains tungsten and molybdenum, which provides the steel with its unique properties such as exceptional heat resistance and a red hardness. HSS is used primarily for cutting tools and other applications where high heat resistance and hardness is required.
In conclusion, steel is an essential material for many applications, from bridges and ships to cars and kitchen appliances. It is available in a variety of forms, including plate, sheet and bar, hot-rolled and cold-rolled varieties. Carbon steel, alloy steels, stainless steel, tool steel and high speed steel are some of the most commonly used types of steel. Steel can be further processed to increase its strength, hardness and formability. No matter what type of steel is needed for an application, it is important to make sure it is of the highest quality to ensure the final product is of the highest quality.
