ASTM A542 / A542M
This specification covers two types of 21⁄4 Cr-1 Mo and three types of Cr-Mo-V alloy steel plates for use in the quenched-and-tempered condition, intended for the fabrication of welded pressure vessels and components.Material under this specification is available in five types, designated “A,” “B,” “C,” “D,” and “E.” B is identical to A except for restrictive limits for carbon,phosphorus, sulfur, and nickel. The material is also available in five classes having the strength levels. E is available only as Class 4 and 4a.The maximum thickness of plates is limited only by the capacity of the chemical composition to meet the specified mechanical property requirements.The minimum thickness of plates is limited to 3⁄16 in. [5 mm].
Grades
| Type | Descriptions |
|---|---|
| A | Class 1 / Class 2 / Class 3 / Class 4 / Class 4a |
| B | Class 1 / Class 2 / Class 3 / Class 4 / Class 4a |
| C | Class 1 / Class 2 / Class 3 / Class 4 / Class 4a |
| D | Class 4a |
| E | Class 4 / Class 4a |
Chemical Properties
| Type | Carbon | Manganese | Phosphorus | Sulfur | Silicon | Chromium | Molybdenum | Copper | Nickel | Vanadium | Titanium | Boron | Columbium | |||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Heat analysis | Product analysis | Heat analysis | Product analysis | Heat analysis | Product analysis | |||||||||||
| A | 0.18 | 0.25–0.66 | 0.025 | 0.025 | 0.50 | 1.88–2.62 | 0.85–1.15 | 0.43 | 0.43 | 0.04 | - | - | - | - | - | - |
| B | 0.09–0.18 | 0.25–0.66 | 0.015 | 0.015 | 0.50 | 1.88–2.62 | 0.85–1.15 | 0.28 | 0.28 | 0.03 | - | - | - | - | - | - |
| C | 0.08–0.18 | 0.25–0.66 | 0.025 | 0.025 | 0.13 | 2.63–3.37 | 0.85–1.15 | 0.28 | 0.28 | 0.18–0.33 | 0.015–0.035 | 0.005–0.045 | 0.001–0.003 | - | - | - |
| D | 0.09–0.18 | 0.25–0.66 | 0.020 | 0.015 | 0.13 | 1.88–2.62 | 0.85–1.15 | 0.23 | 0.28 | 0.23–0.37 | 0.030 | 0.035 | 0.0020 | - | 0.07 | 0.08 |
| E | 0.08–0.18 | 0.25–0.66 | 0.025 | 0.010 | 0.15 | 2.63–3.37 | 0.85–1.15 | 0.28 | 0.28 | 0.18–0.33 | - | - | - | - | 0.015–0.070 | 0.010–0.075 |
Mechanical Properties
| Class |
Tensile strength,min: ksi [MPa] |
Yield strength,min: ksi [MPa] |
Elongation in 2 in. [50 mm] min, %A,B |
|---|---|---|---|
| Class 1 | 105–125 [725–860] |
85 [585] | 14 |
| Class 2 | 115–135 [795–930] |
100 [690] | 13 |
| Class 3 | 95–115 [655–795] | 75 [515] | 20 |
| Class 4 | 85–110 [585–760] | 55 [380] | 20 |
| Class 4a | 85–110 [585–760] | 60 [415] | 18 |
