Special-purpose steel

Stainless steel

The word "Stainless" is a combination of the words "stain" and "less". One of the main characteristics of stainless steel is that is less prone 10 rusting or staining than iron is.Stainless steel’s tend to be sticky and soft. however stainless steels are subject and prone to work hardening.Stainless steel's are generally, divided into three types, 13 chrome stainless steel, 18 chrome stainless steel and 18-8 stainless steel.

However, nowadays there are so many various kinds of stainless steels that there is a need for them to be sub-divided. By changing the composition of the stainless steels the characteristics of can be changed to suit various applications. For example the characteristics that can be changed are (1) to enhance hardening, (2) to improve carburizing" or nitriding", (3) enable solution treatment" to be carried out, (4) to improve free machining property", (5) enhances resistance to corrosion and heat, and (6) to improve the weldability.

Hardened steel

Is a steel with increased hardness that has been achieved by a heat treatment process or a nitriding process. The standard hardness is between 45HRC 10 50HRc and above. Generally, hardened steel or martensitic steels are steels that have been through some kind of heat treatment process.

Heat-resistant alloy, corrosion-resistant alloy

Heat-resistant alloy or corrosion-resistant alloy is a term given to an alloy with sufficient mechanical strength at high temperatures and with high resistance to oxidation and corrosion. The main components of most heat-resistant alloys are iron (Fe), nickel (Ni) and cobalt (Co). Among them, heat-resistant alloy, whose main component is Fe and alloy concentration is 50 percent or under, is called heat-resistant steel. Heat-resistant alloy, whose main component is Fe, Ni or Co but alloy concentration is 50 percent and above, is called super heat-resistant alloy or Superalloy, Most of the superalloys with high strength are Ni-based alloy.

Others

There are several other special-purpose steels. Please refer to the following table.