What is stainless steel?
Stainless steel is essentially a low carbon steel to which chromium has been added. It is this addition of chromium, in amounts greater than 10.5% by weight, that gives the steel its unique 'stainless', corrosion resisting properties.
The chromium content of the steel allows the formation of a tough, adherent, invisible, corrosion resisting chromium oxide film on the steel surface. If damaged mechanically or chemically this film is self healing, provided that oxygen, even in very small amounts, is present. The corrosion resistance as well as other useful properties of the steel are enhanced by increased chromium content and the addition of other elements such as molybdenum, nickel and nitrogen.
Benefits of stainless steels
The bright, easily maintained surface of stainless steel provides an attractive and contemporary appearance, ideal for a myriad of architectural applications.
Lower alloy grades resist corrosion in normal atmospheric and potable water environments, while the more highly alloyed grades can resist corrosion in many acids and alkaline solutions, and some chloride bearing environment, properties which are widely utilised in process plants.
Stainless Steels have high tensile strengths and excellent fatigue properties. Austenitic grades work harden with cold working, and duplex steels allow for reduced thicknesses over traditional grades. Substantial cost savings therefore result as well as increased competitiveness with alternative materials.
Toughness and impact resistance
The austenitic microstructure of the 300 series provides high toughness, from elevated temperatures to far below freezing, making these steels suited to all applications, including cryogenic ones.
Special high chromium and nickel alloyed grades resist scaling and retain strength at high temperatures, up to over 1100°C.
Ease of fabrication
Modern steel manipulation techniques mean that stainless steels can be cut, welded, formed, and fabricated as readily as traditional steels and other materials.
The easy cleanability of stainless steel surfaces makes it the first choice for strict hygiene conditions, such as in hospitals, kitchens, abattoirs and other food processing plants.
Low maintenance costs
Stainless steel normally requires only a periodic wash with soap and water to maintain its original finish.
Long term value
When the total life cycle costs are considered, stainless steel is often the least expensive material option.