ASTM A193 Standard Specification for Alloy-Steel and Stainless Steel Bolting Materials for High-Temperature Service
Grade: B8 — Austenitic Steels/S 30400 (304)
Chemical Requirements (Max. Composition, percent)
C: 0.08
Mn: 2.00
P: 0.035
S: 0.040
Si: 1.00
Cr: 18.0-20.0
Ni: 8.0-11.0
Mechanical Requirements —Metric Products
Class Diameter, [mm] | Tensile Strength, min,MPa | Yield Strength, min, 0.2 % offset, MPa | Elongation in 4D, min, % | Reduction of Area, min, % | Hardness, max |
Classes 1 and 1D | 515 | 205 | 30 | 50 | 223 HB or 96 HRB |
Class 2, M20 and under | 860 | 690 | 12 | 35 | 321 HB or 35 HRC |
| Class 2, over M20 to M24, incl | 795 | 550 | 15 | 35 | 321 HB or 35 HRC |
Class 2, over M24 to M30, incl | 725 | 450 | 20 | 35 | 321 HB or 35 HRC |
| Class 2, over M30 to M36, incl | 690 | 345 | 28 | 45 | 321 HB or 35 HRC |
Class 2B, M48 and under | 655 | 515 | 25 | 40 | 321 HB or 35 HRC |
| Class 2B, over M48 to M64, incl | 620 | 450 | 30 | 40 | 321 HB or 35 HRC |
| Class 2B, over M64 to M72, incl | 550 | 380 | 30 | 40 | 321 HB or 35 HRC |
Heat-treated condition: normalized and tempered, or quenched and tempered, for the ferritic materials, and carbide solution treated (Class 1), carbide solution treated after finishing (Class 1A), and carbide solution treated and strain hardened(Classes 2, 2B and 2C), for the austenitic stainless steels; Classes 1B and 1C apply to the carbide solution-treated nitrogen-bearing stainless steels; Class 1D applies to material carbide solution treated by cooling rapidly from the rolling temperature.
