C276 plate is supplied as the C276 grade of the nickel-molybdenum-chromium family, designated UNS N10276 and Werkstoff 2.4819. The plate contains roughly 15 % molybdenum and 14.5-16.5 % chromium in a nickel base, with iron and tungsten additions, which gives it resistance to reducing conditions as well as to corrosive and oxidising media. Where a drawing, purchase order or stock list refers simply to C276 plate, it refers to this grade. The other grades in the same alloy family are different materials with different chemistry and are not interchangeable.
Related Grades in the Alloy Family
| Grade | UNS | Distinguishing feature |
|---|---|---|
| C276 | N10276 | Balanced resistance to oxidising and reducing media; the general-purpose plate grade |
| C22 | N06022 | Higher chromium content for improved resistance in oxidising media |
| B-2 | N10665 | Nickel-molybdenum alloy intended mainly for hydrochloric acid service |
| Alloy X | N06002 | Nickel-chromium-iron-molybdenum alloy for high-temperature service |
C276 plate contains more molybdenum and iron than C4 plate, which improves its performance in harsh environments. The manufacturing route for C276 is more complex, so the product normally carries a higher price than a lower-carbon grade intended for less aggressive duties.
Chemical Composition of C276 Plate
| Element | Limit (%) |
|---|---|
| Carbon | 0.010 max |
| Manganese | 1.00 max |
| Silicon | 0.08 max |
| Sulfur | 0.03 max |
| Phosphorus | 0.04 max |
| Cobalt | 2.50 max |
| Nickel | 50.99 min, balance |
| Chromium | 14.50-16.50 |
| Iron | 4.00-7.00 |
| Molybdenum | 15.00-17.00 |
Mechanical Properties of C276 Plate
| Property | Value |
|---|---|
| Density | 8.89 g/cm3 |
| Melting point | 1370 degC (2500 degF) |
| Tensile strength | 790 MPa (115 ksi) typical |
| Yield strength, 0.2 % offset | 355 MPa (52 ksi) typical |
| Elongation | 40 % minimum |
Reported typical room-temperature values for plate and for thinner sheet product are compared below. Plate is supplied to the same minimum elongation requirement as sheet, and the hardness of both products stays within the annealed range.
| Product | Ultimate tensile (ksi) | Ultimate tensile (MPa) | Yield (ksi) | Yield (MPa) | Hardness (HRB) |
|---|---|---|---|---|---|
| C276 plate | 107.4 | 741 | 50.3 | 347 | 89 |
| C276 sheet | 115.5 | 796 | 54.6 | 376 | 86 |
Plate Sizes, Thicknesses and Finishes
| Item | Range |
|---|---|
| Specification | ASTM / ASME SB575 |
| Standard plate sizes | 1000 x 2000 mm, 1220 x 2440 mm, 1500 x 3000 mm, 2000 x 2000 mm, 2000 x 4000 mm |
| Thickness | 0.1 mm to 12 mm for sheet and shim, up to 100 mm for heavy plate |
| Width | 10 mm to 2500 mm |
| Forms | Coils, foils, rolls, plain sheet, shim sheet, strip, flats, circles and rings for flanges |
| Finish | Hot rolled, cold rolled, 2B, 2D, BA No.8 and satin with plastic coating |
| Temper | Soft, hard, half hard, quarter hard and spring hard |
Stocked imperial thicknesses run from 0.125 in (3.18 mm) through successive increments to 3 in (76.2 mm), including 0.250 in (6.35 mm), 0.500 in (12.7 mm), 1 in (25.4 mm) and 2 in (50.8 mm). Heavier plate is produced to order.
Frequently Asked Questions
Q: What grade is C276 plate?
It is the C276 grade of the nickel-molybdenum-chromium alloy family, designated UNS N10276 and Werkstoff 2.4819.
Q: Which standard covers C276 plate?
Plate, sheet and strip are covered by ASTM B575 and ASME SB575, with ASTM B906 and ASME SB906 applying to the same product forms.
Q: Is C276 plate different from C276 sheet?
Both are the same grade; sheet is supplied in thinner gauges and narrower coils, while plate is supplied in flat panels up to 100 mm thick.
Q: How does C276 plate differ from C4 plate?
C276 contains more molybdenum and iron for harsher environments, while C4 has lower carbon and a simpler manufacturing route, so C276 normally costs more.
Q: What thickness can be supplied?
Sheet and shim from 0.1 mm, standard plate to 12 mm, and heavy plate to 100 mm, in widths from 10 mm to 2500 mm.
Q: What finishes are available?
Hot rolled and cold rolled plate, 2B, 2D and BA No.8 finishes, and satin finishes with a protective plastic coating.
