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Special steel is a type of steel that is resistant to wear and corrosion. It is produced using a variety of processes, and the quality of the resulting alloy is determined by how it is treated during the production process. Special steel is often used in industrial applications, where it is expected to endure harsh environments and extreme conditions.
The unique properties of special steel are produced by a combination of its chemical composition, microstructure, tempering and case hardening, as well as its heat treatment processes. It is generally recognised as having superior mechanical and physical properties, such as superior wear and corrosion resistance, when compared to other types of steel.
Special steel can generally be classified into two categories: plain carbon steel and alloy steel. Plain carbon steel contains mainly iron, with a small percentage of carbon, and usually no other alloying elements. Alloy steels contain a higher content of alloying elements such as chromium, nickel and molybdenum, which are added to enhance its physical and mechanical properties. Alloy steels are also known as stainless or tool steels.
When compared with plain carbon steel, special steel is usually more expensive, due to its heavy content of alloying elements. However, alloy steels provide a better performance and often last longer than plain carbon steel. This means that the use of alloy steels can prove to be more cost-effective in the long run.
The most common type of alloy steels used in industry are high speed steels, tool steels, die steels, stainless steels, nickel-base alloys, and cobalt-base alloys. High speed steels are specifically designed to withstand extreme environments with high wear and tear, while tool steels typically fall into two categories: cold work and hot work. Cold work tool steels are often used for cutting, forming and stamping operations, whereas hot work tool steels are usually used for hot forging and pressing operations.
Die steels possess higher resistance to abrasion and heat than conventional steels, making them particularly well-suited for die-casting operations. To further increase their toughness, other elements, such as chromium, sulphur, and tungsten, are usually added. Stainless steels are known for their superior corrosion resistance, and are often used in piping and other structures that are exposed to humidity and other corrosive elements. Nickel-base alloys and cobalt-base alloys are specifically designed to withstand high temperatures, and are commonly used in gas turbines, jet engines, and other applications that require superior performance in extreme conditions.
In conclusion, special steel is a highly specialised type of steel, with improved properties that enable it to endure extreme conditions, such as intense heat and pressure. Its superior qualities come at a cost, but its superior performance results in a cost-effective solution in the long run. Alloy steels are available in a number of different forms, each with specific characteristics to suit different industrial applications.
