Specifying Socket Head Cap Screw — GB/T 5281 / ISO 7379 (Series 015) in A2 Stainless Steel pairs the dimensional form of Socket Head Cap Screw — GB/T 5281 / ISO 7379 (Series 015) (GB/T 5281 / ISO 7379) with the engineering properties of A2 Stainless Steel. This page explains when to choose the grade, how it behaves in service, and which grades to compare it against.
Why Choose A2 Stainless Steel for Socket Head Cap Screw — GB/T 5281 / ISO 7379 (Series 015)
The most common stainless grade for indoor and general outdoor fasteners. For socket head cap screw — gb/t 5281 / iso 7379 (series 015), this matters when good general corrosion resistance is the primary requirement.
Mechanical & Physical Properties
| Grade designation | A2-70 (304) |
|---|---|
| Magnetic response | Largely non-magnetic |
| Service temperature | approx. -200 °C to +400 °C |
| Corrosion characteristic | Good general corrosion resistance |
Corrosion Behavior in Service
A2 (304) gives excellent atmospheric and most-water corrosion resistance and is the most common stainless for Socket Head Cap Screw — GB/T 5281 / ISO 7379 (Series 015) in indoor and general outdoor service. In chloride-bearing environments (marine air, road salt, swimming pools) consider stepping up to A4 (316).
Comparable Grades
For Socket Head Cap Screw — GB/T 5281 / ISO 7379 (Series 015), the alternative stainless grade is A4 (316). A2 (304) suits general indoor and outdoor service; A4 (316) adds molybdenum for marine and chloride environments. Where higher strength matters more than corrosion, switch to plated alloy-steel class 8.8 or 10.9.
Sizes of Socket Head Cap Screw — GB/T 5281 / ISO 7379 (Series 015) Available in A2 Stainless Steel
| Size | Pitch (mm) | Length L (mm) | Head diameter dk (mm) | Head height k (mm) | Hex socket s (mm) | Reference standard |
|---|---|---|---|---|---|---|
| M3 | 0.5 | 20 | 5.5 | 3 | 2.5 | ISO 4762 / GB/T 70.1 |
| M4 | 0.7 | 25 | 7.0 | 4 | 3.0 | ISO 4762 / GB/T 70.1 |
| M5 | 0.8 | 30 | 8.5 | 5 | 4.0 | ISO 4762 / GB/T 70.1 |
| M6 | 1.0 | 40 | 10.0 | 6 | 5.0 | ISO 4762 / GB/T 70.1 |
| M8 | 1.25 | 50 | 13.0 | 8 | 6.0 | ISO 4762 / GB/T 70.1 |
| M10 | 1.5 | 60 | 16.0 | 10 | 8.0 | ISO 4762 / GB/T 70.1 |
| M12 | 1.75 | 80 | 18.0 | 12 | 10.0 | ISO 4762 / GB/T 70.1 |
| M14 | 2.0 | 80 | 21.0 | 14 | 12.0 | ISO 4762 / GB/T 70.1 |
| M16 | 2.0 | 100 | 24.0 | 16 | 14.0 | ISO 4762 / GB/T 70.1 |
| M18 | 2.5 | 100 | 27.0 | 18 | 14.0 | ISO 4762 / GB/T 70.1 |
| M20 | 2.5 | 120 | 30.0 | 20 | 17.0 | ISO 4762 / GB/T 70.1 |
| M24 | 3.0 | 150 | 36.0 | 24 | 19.0 | ISO 4762 / GB/T 70.1 |
| M30 | 3.5 | 180 | 45.0 | 30 | 22.0 | ISO 4762 / GB/T 70.1 |
| M36 | 4.0 | 200 | 54.0 | 36 | 27.0 | ISO 4762 / GB/T 70.1 |