ASTM A890 Chemical Composition, Physical Properties
ASTM A890 specifies the chemical composition and phycical properties of ASTM A890 4A, 5A, 6A, 7A, CD4MCuN (1B), CD3MCuN (1C), CE8MN (2A), and CD6MN (3A).
ASTM A890 specification covers a group of cast duplex stainless (austenitic/ferritic). The duplex stainless steel alloys offer a combination of enhanced mechanical properties and corrosion resistance when properly balanced in composition and properly heat-treated. Ferrite levels are not specified, but these alloys will develop a range of approximately 30 to 60% ferrite with the balance austenite.
ASTM A890 material is suitable for making ball valves, which are called duplex ball valves.
ASTM A890 Chemical CompositionA,B
| Material Grade Type UNS |
Element, % | ||||||||
| Carbon | Manganese | Phosphorus | Sulfur | Silicon | Chromium | Nickel | Molybdenum | Nilrogen | |
| CD4MCuN (1B)C 25Cr-5Ni-M0-Cu-N J93372 |
0.04 | 1.0 | 0.04 | 0.04 | 1.0 | 24.5-26.5 | 4.7-6.0 | 1.7-2.3 | 0.10-0.25 |
| CD3MCuN (1C)D 25Cr-6Ni-Mo-Cu-N J93373 |
0.030 | 1.20 | 0.030 | 0.030 | 1.10 | 24.0-26.7 | 5.6-67 | 2.9-38 | 0.22-0.33 |
| CE8MN (2A) 24Cr-10Ni-Mo-N J93345 |
0.08 | 1.00 | 0.04 | 0.04 | 1.50 | 22.5-25.5 | 8.0-11.0 | 3 g.5 | 0.10-0.30 |
| CD6MN (3A) 25Cr-5Ni-Mo-N J93371 |
0.06 | 1.00 | 0.040 | 0.040 | 1.00 | 24.0-27.0 | 4.0-6.0 | 1.75-2.5 | 0.1&-0.25 |
| CD3MN (4A) 22Cr-5Ni-Mo-N J92205 |
0.03 | 1.50 | 0.04 | 0.020 | 1.00 | 21.0-23.5 | 4.5-65 | 2.5-35 | 0.10-0.30 |
| CE3MN (5A)° 25Cr-7Ni-Mo-N J93404 |
0.03 | 1.50 | 0.04 | 0.04 | 1.00 | 24.0-26.0 | 6.0-8.0 | 4.0-5.0 | 0.1G-0.30 |
| CD3MWCUN (6A)E 25Cr-7Ni-Mo-N J93380 |
0.03 | 1.00 | 0.030 | 0.025 | 1.00 | 24.0-26.0 | 6.5-85 | 3.(W.0 | 0.20-0.30 |
| CD3MWN (7A)F 27Cr-7Ni-Mo-W-N J93379 |
0.030 | 1.00-3.00 | 0.030 | 0.020 | 1.00 | 26.0-28.0 | 6.o-e.o | 2.0-3.5 | 0.30-0.40 |
Note:
A - All values are maximums, except where a range is provided.
B - Where ellipses (_) appear in this table, there is no requirement, and the element need not be analyzed for or reported.
C - CD4MCu has been removed from this standard. CD4MCuN is an acceptable substitute for CD4MCu.
D - %Cr + 3.3 x %Mo + 16 x %N N 40.
E - %Cr + 3.3 x (%Mo + (0.5 x %W)) + 16 x %N * 40.
F - %Cr + 3.3 x (%Mo + (0.5 x %W)) + 16 x %N 2 45.
ASTM A890 Physical Properties
