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Stainless Steel

The product has higher resistance to rust and corrosion in many natural and man made environments; however, it is important to select the correct type and grade of stainless steel for the particular application.

Watch straps, cutlery, kitchen ware, cookware, hardware, surgical instruments, major appliances, industrial equipment, structural alloy in automotive and aerospace assembly.
Building structure, building materials in skyscrapers, building facades, pipe and fittings., lift door

Stainless steel grades

Grade Specification
200 Series Austenitic chromium-nickel-manganese alloys
300 Series Austenitic chromium-nickel alloys
400 Series Ferrous and martensitic chromium alloys
500 Series Heat resisting chromium alloys
600 Series Martensitic precipitation hardening alloys

Stainless Steel Types

300 Series
Type Properties
301 Highly ductile, for formed products. Also hardens rapidly during mechanical working. Good weldability. Better wear resistance and fatigue strength than 304.
302 Same corrosion resistance as 304, with slightly higher strength due to additional carbon.
303 Easier machining version of 304 via addition of sulfur and phosphorus.
304 Most common grade; the classic 18/8 stainless steel.
309 Better temperature resistance than 304
316 Second most common grade after 304. Alloy addition of molybdenum prevents specific forms of corrosion.
321 similar to 304 but lower risk of weld decay due to addition of titanium.

400 Series
Type Properties
408 Heat-resistant; poor corrosion resistance; 11% chromium, 8% nickel.
409 Cheapest type, ferrous.
410 Martensitic, wear resistant, but less corrosion resistant.
416 Easy to machine due to additional sulfur
420 "Cutlery Grade" martensitic; excellent polishability.
430 Good formability, but with reduced temperature and corrosion resistance.
440 A higher grade of cutlery steel, with more carbon in it, which allows for much better edge retention when the steel is heat treated properly.

600 Series
Type Properties
630 Most common PH stainless, better known as 17-4; 17% chromium, 4% nickel

Stainless steel finishes

Symbol Finishes
No. 0 Hot Rolled Annealed, thicker plates
No. 1 Hot rolled, annealed and passivated
No. 2D Cold rolled, annealed, pickled and passivated
No. 2B Same as above with additional pass through polished rollers
No. 2BA Bright Annealed (BA) same as above with highly polished rollers
No. 3 Coarse abrasive finish applied mechanically
No. 4 Brushed finish
No. 6 Matte finish
No. 7 Reflective finish
No. 8 Mirror finish