Chemical composition and mechanical properties of SA841 Gr-B, an American grade of pressure vessel steel.
SA841 Gr-B Approximate Grade Lookup Table
SA841 Gr-B Chemical Composition
| Element | Grade B | ||||||||
| C | 0.15 | ||||||||
| Mn t≤(40mm) | 0.70-1.35③ | ||||||||
| Mn t>(40mm) | 1-1.6 | ||||||||
| P | 0.03 | ||||||||
| S | 0.025 | ||||||||
| Si | 0.15-0.50 | ||||||||
| Cu | 0.35 | ||||||||
| Ni | 0.6 | ||||||||
| Cr | 0.25 | ||||||||
| Mo | 0.3 | ||||||||
| Nb | 0.03 | ||||||||
| V | 0.06 | ||||||||
| Ti | ⑦ | ||||||||
| B | ... | ||||||||
| Al,≥ | Total amount 0.02⑦Or acid-soluble aluminum 0.015 | ||||||||
①Unless a minimum or range value is provided, all values are maximum values.
②Below the maximum carbon content, for every 0.01% decrease in carbon, an increase of 0.06% in manganese is permitted above the specified manganese content, up to a maximum manganese content of 1.85%.
③If the carbon content in the smelting analysis does not exceed 0.47%, or does not exceed the value specified in Supplementary Requirement S77, the manganese content in the smelting analysis may exceed 1.35%, up to a maximum of 1.60%. When this requirement is invoked, the carbon equivalent is calculated using the following formula. CE=C+Mn/6+(Cr+Mo+V)/5+(Ni+Cu)/15%
④Not applicable
⑤If the total aluminum content is greater than or equal to 0.03%, or the acid-soluble aluminum content is greater than or equal to 0.025%, then the silicon content can be less than 0.04%.
⑥Cb and Nb are the same element, their names are interchangeable, and both names can be used in the A01 standard.
⑦Titanium may be added to steel according to the design agreement, in which case the minimum aluminum content should no longer apply. When this option is exercised, the smelting analysis content of titanium should be 0.006%-0.02%, and the actual titanium content should be reported in the test report.
⑧Titanium may be added to steel according to the design agreement, in which case the minimum aluminum content should no longer apply. When this option is exercised, the smelting analysis content of titanium should be 0.006%-0.03%, and the actual titanium content should be reported in the test report.
SA841 Gr-A Mechanical Properties
| Type | I | II | |||||||||||||||
| Yield strength,≥,(MPa) | |||||||||||||||||
| ≤1.5in.(40mm) | 345 | 415 | |||||||||||||||
| >1.5in.(40mm)-2.0in.(50mm) | ① | ① | |||||||||||||||
| >1.5in.(40mm)-2.5in.(65mm) | 345 | 415 | |||||||||||||||
| >2.5in.(65mm) | 310 | 380 | |||||||||||||||
| Tensile strength,(MPa) | |||||||||||||||||
| ≤1.5in.(40mm) | 480-620 | 550-690 | |||||||||||||||
| >1.5in.(40mm)-2.0in.(50mm) | 480-620 | 550-690 | |||||||||||||||
| >1.5in.(40mm)-2.5in.(65mm) | |||||||||||||||||
| >2.5in.(65mm) | 450-585 | 515-655 | |||||||||||||||
| Gauge length 2in. (50mm) elongation, % ②≥ | |||||||||||||||||
| ≤1.5in.(40mm) | 22 | 22 | |||||||||||||||
| >1.5in.(40mm)-2.0in.(50mm) | ① | ① | |||||||||||||||
| >1.5in.(40mm)-2.5in.(65mm) | 22 | 22 | |||||||||||||||
| >2.5in.(65mm) | 22 | 22 | |||||||||||||||
| Gauge length 8in. (200mm) elongation, % ②≥ | |||||||||||||||||
| ≤1.5in.(40mm) | 18 | ... | |||||||||||||||
| >1.5in.(40mm)-2.5in.(65mm) | 18 | ... | |||||||||||||||
| >2.5in.(65mm) | 18 | ... | |||||||||||||||
①Not allowed
②For adjustments to elongation, please refer to the A20/A20M standard.