Manufactured to ISO 898-1, Bolt Property Classes are engineering reference supplied by engineeringhardware.com. The dimensional data, materials and selection notes are summarized here.
About This Reference
This is an engineering reference table for bolt property classes based on ISO 898-1. Use it alongside our fastener catalog when selecting and specifying parts.
Reference Data (ISO 898-1)
| Property class | Material | Tensile strength Rm (MPa) | Yield strength Re min (MPa) | Yield ratio | Diameter range | Application | Reference standard |
|---|---|---|---|---|---|---|---|
| 4.6 | Low-carbon steel | 400 | 240 | 0.6 | M5~M100 | General purpose | ISO 898-1 |
| 4.8 | Low-carbon steel (annealed) | 420 | 340 | 0.8 | M1.6~M16 | General purpose | ISO 898-1 |
| 5.6 | Low/medium-carbon steel | 500 | 300 | 0.6 | M5~M100 | General purpose | ISO 898-1 |
| 5.8 | Low/medium-carbon steel | 520 | 420 | 0.8 | M1.6~M24 | General purpose | ISO 898-1 |
| 6.8 | Low/medium-carbon steel | 600 | 480 | 0.8 | M1.6~M24 | General purpose | ISO 898-1 |
| 8.8 | Medium-carbon steel (quenched & tempered) | 830 | 660 | 0.8 | M16~M72 | High strength, most common | ISO 898-1 |
| 8.8 | Low-alloy steel (quenched & tempered) | 800 | 640 | 0.8 | M1.6~M16 | High strength, most common | ISO 898-1 |
| 9.8 | Medium-carbon steel | 900 | 720 | 0.8 | M1.6~M16 | High strength | ISO 898-1 |
| 10.9 | Alloy steel (quenched & tempered) | 1040 | 940 | 0.9 | M5~M100 | Ultra-high strength | ISO 898-1 |
| 12.9 | Alloy steel (quenched & tempered) | 1220 | 1100 | 0.9 | M1.6~M100 | Very high strength, common for socket screws | ISO 898-1 |

