Stainless steel is the name of a high alloy steel used mainly for its anti-corrosion properties. The main characteristic of the stainless steel family is that they all contain a minimum of 10.5 percent of chromium. This enables the steel to withstand corrosive atmospheres or erosive chemical environments.
What is Stainless Steel?
Stainless steel does not readily corrode, rust or stain with water as ordinary steel does, but despite the name it is not fully stain-proof, most notably under low oxygen, high salinity, or poor circulation environments. There are different grades and surface finishes of stainless steel to suit the environment the alloy must endure. Stainless steel is used where both the properties of steel and resistance to corrosion are required.
History of Stainless Steel
Sheffield, England born Harry Brearly discovered stainless steel in 1913. In an experiment, he found that steel’s corrosion
resistance increased when the chromium content is raised to 12 percent or more. He is seen as the person who laid the
foundation for the development of various stainless steel grades.
Stainless steel is susceptible to certain types of corrosion despite the fact that one of the main reasons for using stainless steel is its resistance to corrosion. The different kinds of corrosion affecting stainless steel are:
General Corrosion, pitting corrosion, crevice corrosion, stress corrosion cracking, sulphide stress corrosion cracking, intergranular corrosion, galvanic corrosion and contact corrosion.
Stainless Steel Categories
Stainless steel is divided into 5 main categories. These are Austenitic, martensitic, ferritic, duplex and precipitation hardening.
200 Series Austenitic – Alloys: 201, 202, 203, 204 & 205 is a chromium-nickel-manganese alloy with high strength in the annealed. This series is non-magnetic, not heat treatable and has excellent formability for sever forming applications. It is used in structural applications and for the manufacture of washing machine tubs.
The main elements in stainless steel
Stainless steel or corrosion-resistant steel is a kind of metallic alloy that is found in a variety of forms. It serves our practical needs so well that it is difficult to find any sphere of our life, where we do not use this type of steel. The major components of stainless steel are: iron, chromium, carbon, nickel, molybdenum and small quantities of other metals.
Stainless steel is a very versatile and useful material used in a wide variety of applications. It is used in the following fields:
- Cutlery and kitchenware
- Home appliance
- Chemical processing and oil & gas industries
- Power generation
- Food production
- Architecture, building and construction
- Medical applications
- Automotive parts