ASTM A240/A240M:2025 S81921: S81921: duplex (austenitic-ferritic) stainless steel plate, sheet and strip (UNS number, no type name printed). Specified in ASTM A240/A240M:2025.
Matched by chemical composition and mechanical properties, not a formal equivalence claim. Always verify against the applicable standard before substitution.
Chemical Composition (%)
C
Mn
P
S
Si
Cr
Ni
Mo
N
<=0.030
2.00-4.00
<=0.040
<=0.030
<=1.00
19.0-22.0
2.0-4.0
1.00-2.00
0.14-0.20
Mechanical Properties
Tensile Strength
>=620 MPa
Yield Strength
>=450 MPa
Elongation
>=25%
Hardness
<=293 HB
Condition
Plate, sheet and strip; yield by 0.2 percent offset
More data from ASTM A240/A240M:2025
From the standard
Mechanical properties1 condition(s)
Product or thickness
Tensile strength, min (MPa)
Yield strength, min (MPa)
Elongation in 50 mm, min (%)
All
620
450
25
Minimum values; yield strength by the 0.2 percent offset method.
Source: ASTM A240/A240M:2025, Table 2
Hardness1 condition(s)
Product or thickness
Brinell HBW, max
Rockwell, max
All
293
31 HRC
Maximum values; either Brinell or Rockwell scale may be used.
Source: ASTM A240/A240M:2025, Table 2
Cold bend1 value
Cold bend angle
not required
Bend tests are not required for chromium steels thicker than 1 in. [25 mm] or for any austenitic or duplex steel regardless of thickness.
Source: ASTM A240/A240M:2025, Table 2
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