T-Slot Nuts manufactured in Property Class 12.9 Steel (ISO 898-1 property class 12.9) are dimensioned to DIN 508. The sections below give the mechanical and physical properties of the grade, its behavior in corrosive and elevated-temperature service, and the full size table.
Why Choose Property Class 12.9 Steel for T-Slot Nuts
The highest common strength class, for high-load machine assembly. For t-slot nuts, this matters when requires plating or black-oxide protection is the primary requirement.
Mechanical & Physical Properties
| Grade designation | ISO 898-1 property class 12.9 |
|---|---|
| Magnetic response | Magnetic |
| Service temperature | commonly limited to approx. +300 °C; confirm against the coating and the load |
| Corrosion characteristic | Requires plating or black-oxide protection |
Corrosion Behavior in Service
Carbon and alloy steel t-slot nuts require a coating for corrosion protection. Zinc plating (with or without passivation) is the most common; hot-dip galvanizing is used for outdoor structural service; black-oxide is mainly a tarnish-prevention finish for tool-room use.
Comparable Grades
For T-Slot Nuts, class 8.8 is the comparable strength step. Move up when the joint preload approaches the proof load of the current class; move down when the joint is over-specified. For corrosion-critical service, switch to stainless A2 or A4.
Sizes of T-Slot Nuts Available in Property Class 12.9 Steel
| Size | T-slot width a (mm) | Nut width b (mm) | Total height h (mm) | Neck height k (mm) | Chamfer f (mm) | Reference standard |
|---|---|---|---|---|---|---|
| M4 | 5 | 9 | 6.5 | 3 | 1 | DIN 508 |
| M5 | 6 | 10 | 8 | 4 | 1.6 | DIN 508 |
| M6 | 8 | 13 | 10 | 6 | 1.6 | DIN 508 |
| M8 | 10 | 15 | 12 | 6 | 1.6 | DIN 508 |
| M10 | 12 | 18 | 14 | 7 | 2.5 | DIN 508 |
| M12 | 14 | 22 | 16 | 8 | 2.5 | DIN 508 |
| M16 | 18 | 28 | 20 | 10 | 2.5 | DIN 508 |
| M20 | 22 | 35 | 28 | 14 | 2.5 | DIN 508 |
| M24 | 28 | 44 | 36 | 18 | 4 | DIN 508 |
| M30 | 36 | 54 | 44 | 22 | 6 | DIN 508 |
| M36 | 42 | 65 | 52 | 26 | 6 | DIN 508 |
| M42 | 48 | 75 | 60 | 30 | 6 | DIN 508 |
| M48 | 54 | 85 | 70 | 34 | 6 | DIN 508 |
