410 vs 201 Stainless Steel: Strength and Corrosion Trade - offs

Type 410 and Type 201 belong to two different stainless families and are rarely true substitutes. 410 (UNS S41000, JIS SUS410) is a martensitic grade: hardenable by heat treatment, magnetic, and chosen for wear resistance. 201 (UNS S20100) is an austenitic grade that substitutes manganese and nitrogen for part of the nickel: non-magnetic in the annealed condition, highly formable, and chosen for cost-effective fabrication. This article compares them across the properties that decide real applications.

Chemical Composition

Composition below is per JIS G4304 (SUS410) and ASTM A240 (S20100).

Element (wt%)	410 (JIS G4304 SUS410)	201 (ASTM A240 S20100)
C	≤0.15	≤0.15
Si	≤1.00	≤0.75
Mn	≤1.00	5.50-7.50
P	≤0.040	≤0.060
S	≤0.030	≤0.030
Cr	11.50-13.50	16.0-18.0
Ni	≤0.60	3.5-5.5
N	-	≤0.25

Mechanical Properties

Property	410 (annealed, JIS G4304)	201 (annealed, ASTM A240)
Tensile strength (MPa)	≥410	≥655
Yield strength (MPa)	≥205	≥310
Elongation (%)	≥20	≥40
Hardness	≤201 HB	-

Two different stories: 201 is stronger in the as-supplied condition, but 410 is the grade that can be hardened by quench-and-temper to a level 201 can never reach; typical heat-treated 410 reaches about 35-45 HRC depending on the tempering temperature. 201 also work-hardens rapidly during cold forming.

Corrosion Resistance

In dry indoor and low-humidity environments, 201 generally offers better corrosion resistance than 410, because its higher chromium, 16-18% versus 11.5-13.5%, forms a more protective passive film and its carbon does not sit in a martensitic matrix. The higher carbon of 410 reduces corrosion resistance and makes it prone to rust in damp or mildly corrosive conditions. Neither grade approaches 304 or 316 in chloride resistance: a calculated PREN for 410 is about 12-13 versus about 19-20 for 201.

Magnetic Behaviour

410 is ferromagnetic because of its martensitic structure. 201 is austenitic and essentially non-magnetic in the annealed condition, although cold working can induce slight magnetism. Where magnetic response is needed, for example in sensors or magnetic chucks, 410 is useful; where it must be avoided, 201 is the choice.

Fabrication, Welding and Cost

410 is weldable with caution: preheat and post-weld heat treatment are normally required to avoid hard, crack-sensitive heat-affected zones, and welding is usually avoided for highly stressed joints. 201 welds much like 304 and is easy to form, roll and draw. On cost, 201 is one of the least expensive austenitic grades; 410 is also a low-cost grade, and both sit well below 304 and 316 in price (market data).

Typical Applications

410: knife blades, valve stems and seats, pump shafts, steam-turbine blades, fasteners and wear parts where hardness matters. 201: cookware, kitchen utensils, decorative architectural panels, furniture frames, automotive trim and light structural components.

FAQ

1. Which is stronger, 410 or 201?

As supplied, 201 is stronger, with yield strength ≥310 MPa versus ≥205 MPa for annealed 410. But 410 can be hardened by heat treatment to far higher hardness and strength, which is why it is used for cutting edges and wear surfaces.

2. Which resists rust better?

201 in normal indoor and low-humidity service. The higher carbon and lower chromium of 410 make it more susceptible to rust in damp conditions.

3. Is 410 magnetic?

Yes. The martensitic structure is ferromagnetic. 201 is essentially non-magnetic in the annealed condition.

4. Can 410 be welded easily?

Not like austenitic grades. 410 requires preheat and post-weld heat treatment to prevent cracking in the heat-affected zone, and welded joints are generally not used where high strength is required.

5. How do I choose between 410 and 201?

If the part needs hardness, wear resistance or magnetic response, choose 410. If it needs forming, welding, non-magnetic behaviour or cost-effective fabrication in mildly corrosive indoor service, choose 201.