Page 16 - Industrial Technology EXTRA - 29th June 2020

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When to specify stainless steel

for your component parts

John Marshall, Technical Manager at WDS Components Parts, explains the

advantages of stainless steel for standard and component parts
tainless steel is a material often specified their own characteristic and costs – so it's important
for engineering projects due to its to make the right choice for your application.
combination of strength and corrosion It's the chromium alloy which gives stainless
Sresistance. However, there are various steel its best known advantage - high resistance to
grades of stainless steel to choose from – each with corrosion. The chrome component not only creates
the corrosion resistant chromium oxide protective
layer, but also contributes to its hardness, making it
highly robust and resistant to impact. However, its
relative hardness makes it more difficult to machine
than mild steel, which means careful selection over
your supplier is required in order to ensure optimum
product quality and accuracy.
Type 304 is the most common type of stainless
steel for component parts, composed of up to 20%
chromium, enhancing its resistance to corrosion. It's
often used in areas which are mildly corrosive or
which require only an occasional washdown, for
example handles or hinges. For this reason, it's also
a more economical choice. Type 303 has similar
properties but slightly improved machinability when
very low tolerances are required, but with slightly
lower durability.
The highest quality stainless steel generally
used for standard parts and components is
Type 316. It's added molybdenum
component makes it highly resistant to
corrosion as well as pitting, the effects of
which would create a less hygienic environment and
accelerate corrosion. Known as 'food grade' (though

June 2020 • INDUSTRIAL TECHNOLOGY EXTRA! • p16