Chemical composition and mechanical properties of SA738 Gr-C, an American grade of pressure vessel steel.
SA738 Gr-C Approximate Grade Lookup Table
SA738 Gr-C Chemical Composition
| C① | ≤0.20 | |||||||||||
| Mn | Smelting Analysis | ≤1.5in.（40mm） | ≤1.50 | |||||||||
| ＞1.5-2.0in.(40-50mm） | ≤1.50 | |||||||||||
| ＞2.0-2.5in.(50-65mm) | ≤1.50 | |||||||||||
| ＞2.5in.（65mm） | ≤1.60 | |||||||||||
| Finished Product Analysis | ≤1.5in.（40mm） | ≤1.62 | ||||||||||
| ＞1.5-2.0in.(40-50mm） | ≤1.62 | |||||||||||
| ＞2.0-2.5in.(50-65mm) | ≤1.62 | |||||||||||
| ＞2.5in.（65mm） | ≤1.72 | |||||||||||
| P① | ≤0.025 | |||||||||||
| S① | ≤0.025 | |||||||||||
| Si | Smelting Analysis | 0.15-0.50 | ||||||||||
| Finished Product Analysis | 0.13-0.55 | |||||||||||
| Cu | Smelting Analysis | ≤0.35 | ||||||||||
| Finished Product Analysis | ≤0.38 | |||||||||||
| Ni | Smelting Analysis | ≤0.50 | ||||||||||
| Finished Product Analysis | ≤0.53 | |||||||||||
| Cr | Smelting Analysis | ≤0.25 | ||||||||||
| Finished Product Analysis | ≤0.29 | |||||||||||
| Mo | Smelting Analysis | ≤1.5in.（40mm） | ≤0.08 | |||||||||
| ＞1.5in.(40mm） | ≤0.08 | |||||||||||
| Finished Product Analysis | ≤1.5in.（40mm） | ≤0.09 | ||||||||||
| ＞1.5in.(40mm） | ≤0.09 | |||||||||||
| V | Smelting Analysis | ≤0.05 | ||||||||||
| Finished Product Analysis | ≤0.05 | |||||||||||
| Nb | Smelting Analysis | ... | ||||||||||
| Finished Product Analysis | ... | |||||||||||
| Nb+V | Smelting Analysis | ... | ||||||||||
| Finished Product Analysis | ... | |||||||||||
| Ti | ... | |||||||||||
| B | ... | |||||||||||
| Ti | ... | |||||||||||
①Both smelting analysis and finished product analysis are applicable.
②Vanadium and niobium can only be added after consultation and agreement between the steel plate manufacturer and the purchasing party.
SA738 Gr-C Mechanical Properties
| Tensile strength,（MPa） | |||||||||||||||
| ≤1.5in.（40mm） | 550-690 | ||||||||||||||
| ＞1.5in.（40mm）-2.0in.（50mm） | 550-690 | ||||||||||||||
| ＞2.0in.（50mm）-2.5in.（65mm） | 550-690 | ||||||||||||||
| ＞2.5in.（65mm）-4in.（100mm） | 515-655 | ||||||||||||||
| ＞4in.（100mm） | 485-620 | ||||||||||||||
| Yield strength,（MPa） | |||||||||||||||
| ≤1.5in.（40mm） | 415 | ||||||||||||||
| ＞1.5in.（40mm）-2.0in.（50mm） | 415 | ||||||||||||||
| ＞2.0in.（50mm）-2.5in.（65mm） | 415 | ||||||||||||||
| ＞2.5in.（65mm）-4in.（100mm） | 380 | ||||||||||||||
| ＞4in.（100mm） | 315 | ||||||||||||||
| Gauge length 2in. (50mm) elongation, % ②≥ | |||||||||||||||
| ≤1.5in.（40mm） | 22 | ||||||||||||||
| ＞1.5in.（40mm）-4in.（100mm） | 22 | ||||||||||||||
| ＞4in.（100mm） | 20 | ||||||||||||||
①Not allowed
②For adjustments to elongation, please refer to the A20/A20M standard.