Grade 8.8 Steel Tab Lock Washer for Round Nut are stocked to GB/T 858. The grade provides requires plating (zinc) for corrosion protection and is magnetic; the practical service range is up to approx. +300 °C. Property data, grade comparison and the full size table follow.
Why Choose Grade 8.8 Steel for Tab Lock Washer for Round Nut — GB/T 858 (Series 072)
The workhorse medium-carbon alloy grade for structural joints. For tab lock washer for round nut — gb/t 858 (series 072), this matters when requires plating (zinc) for corrosion protection is the primary requirement.
Mechanical & Physical Properties
| Grade designation | class 8.8 |
|---|---|
| Magnetic response | Magnetic |
| Service temperature | up to approx. +300 °C |
| Corrosion characteristic | Requires plating (zinc) for corrosion protection |
Corrosion Behavior in Service
Carbon and alloy steel tab lock washer for round nut — gb/t 858 (series 072) 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.
Galvanic & Galling Considerations
For tab lock washer for round nut — gb/t 858 (series 072) in steel, the dominant compatibility issue is hydrogen embrittlement at high property classes (10.9 and above) when electroplated. Plating must be followed by an appropriate baking treatment, or a non-electroplated finish (mechanical zinc, zinc flake) should be substituted.
Sizes of Tab Lock Washer for Round Nut — GB/T 858 (Series 072) Available in Grade 8.8 Steel
| For shaft / nut size | Inner diameter d1 (mm) | Outer diameter d2 (mm) | Thickness t (mm) | Tab length (mm) | Reference standard |
|---|---|---|---|---|---|
| M10 | 10.5 | 21 | 1.0 | 8 | GB/T 858 |
| M12 | 12.5 | 25 | 1.0 | 9 | GB/T 858 |
| M16 | 16.5 | 30 | 1.0 | 10 | GB/T 858 |
| M20 | 20.5 | 38 | 1.5 | 12 | GB/T 858 |
| M24 | 24.5 | 45 | 1.5 | 14 | GB/T 858 |
| M30 | 30.5 | 55 | 1.5 | 16 | GB/T 858 |
| M36 | 36.5 | 65 | 2.0 | 18 | GB/T 858 |
| M48 | 48.5 | 85 | 2.0 | 20 | GB/T 858 |
| M60 | 60.5 | 105 | 2.5 | 24 | GB/T 858 |