When Spring Lock Washer — GB/T 5782 / ISO 4014 (Series 003) are required in Grade 8.8 Steel, the alternative grades and the trade-offs between them matter as much as the dimensions. This page covers both, plus mechanical and corrosion data.
Why Choose Grade 8.8 Steel for Spring Lock Washer — GB/T 5782 / ISO 4014 (Series 003)
The workhorse medium-carbon alloy grade for structural joints. For spring lock washer — gb/t 5782 / iso 4014 (series 003), 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 spring lock washer — gb/t 5782 / iso 4014 (series 003) 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 spring lock washer — gb/t 5782 / iso 4014 (series 003) 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 Spring Lock Washer — GB/T 5782 / ISO 4014 (Series 003) Available in Grade 8.8 Steel
| For bolt size | Inner diameter d1 (mm) | Outer diameter d2 (mm) | Width b (mm) | Thickness t (mm) | Reference standard |
|---|---|---|---|---|---|
| M3 | 3.1 | 6.2 | 1.0 | 0.8 | GB/T 93 / DIN 127B |
| M4 | 4.1 | 7.6 | 1.2 | 1.0 | GB/T 93 / DIN 127B |
| M5 | 5.1 | 9.2 | 1.5 | 1.2 | GB/T 93 / DIN 127B |
| M6 | 6.1 | 11.8 | 2.0 | 1.6 | GB/T 93 / DIN 127B |
| M8 | 8.1 | 14.8 | 2.5 | 2.0 | GB/T 93 / DIN 127B |
| M10 | 10.2 | 18.1 | 3.0 | 2.5 | GB/T 93 / DIN 127B |
| M12 | 12.2 | 21.1 | 3.5 | 3.0 | GB/T 93 / DIN 127B |
| M14 | 14.2 | 24.1 | 4.0 | 3.5 | GB/T 93 / DIN 127B |
| M16 | 16.2 | 27.4 | 4.5 | 4.0 | GB/T 93 / DIN 127B |
| M18 | 18.2 | 29.4 | 5.0 | 4.5 | GB/T 93 / DIN 127B |
| M20 | 20.2 | 33.6 | 5.5 | 5.0 | GB/T 93 / DIN 127B |
| M24 | 24.5 | 40.1 | 6.5 | 6.0 | GB/T 93 / DIN 127B |
| M30 | 30.5 | 50.0 | 8.0 | 7.5 | GB/T 93 / DIN 127B |