ASTM A240 is a standard specification by ASTM International, defining requirements for chromium, chromium-nickel, and chromium-manganese-nickel stainless steel plate, sheet, and strip, primarily for pressure vessels and general applications like construction, architecture, and appliances. It covers various grades (e.g., 304, 316) by detailing chemical composition, mechanical properties, and quality standards, ensuring material suitability and performance.
ASTM A240 Grade
| Type | Raw Material |
|---|---|
| 304 | 18 - 8 Chromium Nickel Austenitic Stainless Steel |
| 316L | Low Carbon, Chromium Nickel Molybdenum Austenitic Stainless Steel |
| 321 | Titanium Stabilized 18 - 8 Chromium Nickel Austenitic Stainless Steel |
| 410 | 12% Straight Chromium Martensitic Stainless Steel |
| 904L | High Nickel Molybdenum Super Austenitic Stainless Steel |
| UNS S31803 | Ferritic / Austenitic Duplex Stainless Steel |
| UNS S32750 | Ferritic / Austenitic Super Duplex Stainless Steel |
| UNS S31254 | High Moly Austenitic Stainless Steel |
ASTM A240 Equivalent
| ASTM | BS 970 1991 | AISI / SAE | Werkstoff |
|---|---|---|---|
| A240 SS 304L | 304S11 | 304L | 1.4306 |
| A240 SS 304 | 304S15 | 304 | 1.4301 |
| A240 SS 316L | 316S11 | 316L | 1.4404 |
| A240 SS 316L | 316S13 | 316L | 1.4435 |
| A240 SS 316 | 316S31 | 316 | 1.4401 |
| A240 SS 316 | 316S33 | 316 | 1.4436 |
ASTM A240 Chemical Composition
| Element | 304 | 316 | 321 | 410 | 904L | S31803 | S32750 | S31254 |
|---|---|---|---|---|---|---|---|---|
| Carbon | 0.07 | 0.08 | 0.08 | 0.08 - 0.15 | 0.02 | 0.03 | 0.03 | 0.02 |
| Manganese, max | 2.00 | 2.00 | 2.00 | 1.00 | 2.00 | 2.00 | 1.20 | 1.00 |
| Phosphorus, max | 0.045 | 0.045 | 0.045 | 0.040 | 0.045 | 0.030 | 0.035 | 0.030 |
| Sulfur, max | 0.030 | 0.030 | 0.030 | 0.030 | 0.035 | 0.020 | 0.020 | 0.010 |
| Silicon | 0.75 | 0.75 | 0.75 | 1.00 | 1.00 | 1.00 | 0.80 | 0.80 |
| Chromium | 17.50 - 19.50 | 16.00 - 18.00 | 17.00 - 19.00 | 11.50 - 13.50 | 19.00 - 23.00 | 21.00 - 23.00 | 24.00 - 26.00 | 19.50 - 20.50 |
| Nickel | 8.00 - 10.50 | 10.00 - 14.00 | 9.00 - 12.00 | 0.75 | 23.00 - 28.00 | 4.50 - 6.50 | 6.00 - 8.00 | 17.50 - 18.50 |
| Molybdenum | ... | 2.00 - 3.00 | ... | ... | 4.00 - 5.00 | 2.50 - 3.50 | 3.00 - 5.00 | 6.00 - 6.50 |
| Nitrogen | 0.10 max | 0.10 max | 0.10 max | ... | 0.10 max | 0.08 - 0.20 | 0.24 - 0.32 | 0.18 - 0.25 |
| Copper, max | ... | ... | ... | ... | 1.00 - 2.00 | ... | 0.50 | 0.50 - 1.00 |
| Titanium | ... | ... | 5 x (C+N) - 0.70 | ... | ... | ... | ... | ... |
ASTM A240 Physical Properties
| Type | Tensile Strength, ksi, min | Yield Strength, ksi, min | Elongation, % min | Hardness, max^A |
|---|---|---|---|---|
| 304 | 75 | 30 | 40 | 201 HBW or 92 HRB |
| 316 | 75 | 30 | 40 | 217 HBW or 95 HRB |
| 321 | 75 | 30 | 40 | 217 HBW or 95 HRB |
| 410 | 65 | 30 | 20 | 217 HBW or 96 HRB |
| 904L | 71 | 31 | 35 | 95 HRB |
| UNS S31803 | 90 | 65 | 25 | 293 HBW or 31 HRC |
| UNS S32750 | 116 | 80 | 15 | 310 HBW or 32 HRC |
| UNS S31254 | 100 | 45 | 35 | 223 HBW or 96 HRB |
What is the difference between ASTM A182 and A240?
ASTM A240 is stainless steel plate that offers strength at high temperatures, and high corrosion resistance. While ASTM A182 and ASTM A240 have similar chemical properties, the production method differs: A240 is plate; A182 is forged, which may affect materials choice.
What is the difference between ASTM A276 and ASTM A240?
ASTM A240 is a standard specification for specifying steel sheets, plates, and strips for pressure vessels, fusion-welded pressure vessels, and general applications. A276, on the other hand, serves as a standard specification for stainless steel bars and shapes.
What is the difference between ASTM A240 and A312?
Essentially, A240 is more suitable for structural applications like ships, tanks, and bridges, while A312 is designed for high-temperature and high-pressure applications like chemical processing plants and power generation.