202 Stainless Steel: Chromium-Manganese Austenitic Grade Explained

What Is 202 Stainless Steel?

202 stainless steel is an austenitic chromium-manganese-nickel grade from the 200 series. Where type 304 relies on roughly 8% nickel to hold its austenitic structure, grade 202 substitutes 7.50-10.00% manganese together with up to 0.25% nitrogen, which stabilises austenite at a much lower nickel level. The practical result is a bright, essentially non-magnetic material that looks and fabricates much like a 300 series grade while carrying a substantially lower alloy cost.

The grade is specified as UNS S20200 in ASTM A240/A240M for flat-rolled product and ASTM A276/A276M for bars, as EN 1.4373 (X12CrMnNiN18-9-5) in EN 10088-2, and as SUS 202 in JIS G4305. Comparable chromium-manganese-nickel-nitrogen grades are listed in GB/T 20878, and sheet, strip and coil are commonly supplied to GB/T 3280 and GB/T 4237.

Chemical Composition and Typical Mechanical Properties

Element	UNS S20200 (ASTM A240/A240M)
Carbon (C)	0.15% max
Manganese (Mn)	7.50-10.00%
Phosphorus (P)	0.060% max
Sulfur (S)	0.030% max
Silicon (Si)	1.00% max
Chromium (Cr)	17.00-19.00%
Nickel (Ni)	4.00-6.00%
Nitrogen (N)	0.25% max

Annealed material is typically supplied with a minimum tensile strength in the region of 620 MPa, a 0.20% proof stress of about 310 MPa and an elongation of about 40%. Cold-rolled strip, drawn tube and formed sections are appreciably stronger because the grade work hardens quickly. Purchasing decisions should always be based on the values printed on the mill certificate and the requirements of the applicable product specification rather than on catalogue averages.

Corrosion Behaviour: Where 202 Performs and Where It Does Not

Calculated from its chromium and nitrogen content, the pitting resistance equivalent number of 202 can fall within roughly the same 17-23 band quoted for type 304. In real service, however, 202 is the less tolerant of the two grades. It contains no molybdenum and only about half the nickel of 304, so it has less capacity to re-passivate and to tolerate chlorides that remain in contact with the surface.

Under dry inland, urban and interior exposure the grade performs well: it does not rust, fade or discolour under normal weathering. In coastal atmospheres, on de-icing-salt routes, in heavily polluted industrial areas and around swimming pools, tea staining and pitting can appear, especially in crevices, beneath dirt deposits and at weld discolouration. Grade 202 is therefore not a marine grade and should not be substituted for 316 in salt-loaded environments.

The grade is widely sold for kitchenware and restaurant hardware, yet many potable-water and food-contact specifications name 304 or 316 instead. The high manganese level restricts 202 in a number of food-contact and drinking-water standards, and prolonged contact with chlorides or acidic foods can cause pitting. For sinks, food processing equipment, dairy lines and potable-water systems, specify 304 or 316 rather than 202.

Typical Applications of 202 Stainless Steel

Decorative and structural tube: handrails, balustrades, glass-fixing profiles, stair and platform rails

Architectural trim: door and window frames, shopfronts, column cladding, lift car panelling

Municipal and transport work: highway guardrails, bus and rail interior trim, escalator cladding

Public furniture: benches, litter bins, trolley frames, shelving and display stands

Commercial hardware: furniture frames, bathroom fittings, supermarket fixtures, signage supports

General decorative kitchenware and sinks where a low-cost bright finish matters more than maximum corrosion resistance

Forming, Welding and Fabrication Notes

Formability: ductility in the annealed condition is good, and the grade bends, rolls and draws in a similar way to 304, although springback is slightly higher.

Work hardening: strength and a mild magnetic response rise quickly with cold reduction, so severe drawing schedules need inter-stage annealing.

Welding: TIG and gas metal arc welding with matching chromium-manganese-nickel filler produce sound joints. Control heat input and interpass temperature, purge the back of the joint, and pickle or passivate afterwards to restore the passive film.

Machining: the grade produces a gummy chip similar to other austenitic steels; use sharp tooling, low cutting speeds and generous cutting fluid.

Installation hygiene: remove weld spatter, embedded iron and carbon steel contamination, which are the usual cause of rust spots reported on installed 202 components.

Frequently Asked Questions About 202 Stainless Steel

Q: Is 202 stainless steel magnetic?
Annealed 202 is essentially non-magnetic. Cold working such as tube bending or deep drawing forms strain-induced martensite and produces a noticeable magnetic pull; this is normal behaviour for an austenitic grade and is not a defect.

Q: Does 202 stainless steel rust?
In dry inland and interior service it resists rusting well. In coastal, de-icing or heavily polluted atmospheres, and wherever chlorides remain on the surface or sit in crevices, tea staining and pitting can develop. A regular fresh-water rinse keeps the surface passive.

Q: Is 202 a good substitute for 304?
For interior decorative work in dry conditions, 202 delivers a comparable appearance at lower cost. For food contact, potable water, marine exposure, chemical process duty or long-life architectural facades, specify 304 or 316 instead.

Q: What is the difference between the 200 and 300 series?
The 200 series replaces part of the nickel with manganese and nitrogen, which lowers the alloy cost and, in grade 202, reduces chloride tolerance. The 300 series is chromium-nickel austenitic steel, typically 18% chromium with 8% or more nickel, which gives better all-round corrosion resistance.

Q: Can 202 stainless steel be welded?
Yes. TIG and gas metal arc welding with matching chromium-manganese-nickel filler are standard practice. Keep interpass temperature low, purge the weld root, and pickle or passivate the weld zone so that heat tint does not become a pitting site.

Q: What product forms is 202 supplied in?
Cold-rolled coil, sheet and strip, hot-rolled plate, welded and drawn tube, decorative round and square tube, and bar. Dimensions, tolerances and finish are agreed against the relevant ASTM, EN, JIS or GB standard.