Why do they call it "Stainless Steel"?

Why do they call it "Stainless Steel"?

Because It does not rust and is non magnetic.

Although stainless steel is much more resistant to corrosion than ordinary carbon or alloy steels, in some circumstances it can corrode. It is 'stain-less' not 'stain-impossible'. In normal atmospheric or water based environments, stainless steel will not corrode as demonstrated by domestic sink units, cutlery, saucepans and work-surfaces.

See more:





In more aggressive conditions, the basic types of stainless steel may corrode and a more highly alloyed stainless steel can be used

History of Stainless Steel


In 1913, English metallurgist Harry Brearly, working on a project to improve rifle barrels, accidentally discovered that adding chromium to low carbon steel gives it stain resistance. In addition to iron, carbon, and chromium, modern stainless steel may also contain other elements, such as nickel, niobium, molybdenum, and titanium.

Nickel, molybdenum, niobium, and chromium enhance the corrosion resistance of stainless steel. It is the addition of a minimum of 12% chromium to the steel that makes it resist rust, or stain 'less' than other types of steel. The chromium in the steel combines with oxygen in the atmosphere to form a thin, invisible layer of chrome-containing oxide, called the passive film. 

The sizes of chromium atoms and their oxides are similar, so they pack neatly together on the surface of the metal, forming a stable layer only a few atoms thick. If the metal is cut or scratched and the passive film is disrupted, more oxide will quickly form and recover the exposed surface, protecting it from oxidative corrosion. (Iron, on the other hand, rusts quickly because atomic iron is much smaller than its oxide, so the oxide forms a loose rather than tightly-packed layer and flakes away.) 

The passive film requires oxygen to self-repair, so stainless steels have poor corrosion resistance in low-oxygen and poor circulation environments. In seawater, chlorides from the salt will attack and destroy the passive film more quickly than it can be repaired in a low oxygen environment.

What is stainless steel used for?


Stainless steels of various kinds are used in thousands of applications. The following gives a flavour of the full range:


Domestic – cutlery, sinks, saucepans, washing machine drums, microwave oven liners, razor blades
Architectural/Civil Engineering – cladding, handrails, door and window fittings, street furniture, structural sections, reinforcement bar, lighting columns, lintels, masonry supports



Transport – exhaust systems, car trim/grilles, road tankers, ship containers, ships chemical tankers, refuse vehicles


Chemical/Pharmaceutical – pressure vessels, process piping.

Oil and Gas – platform accommodation, cable trays, subsea pipelines.

Medical – Surgical instruments, surgical implants, MRI scanners.


Food and Drink – Catering equipment, brewing, distilling, food processing.


Water – Water and sewage treatment, water tubing, hot water tanks.


General – springs, fasteners (bolts, nuts and washers), wire.

Add your own answer in the comments!

0 comments :

Post a Comment