A2 Stainless Steel Wedge-Lock Washer Pairs combine the dimensional form of Trade series (cam wedge-lock pair) with the material properties of grade ISO 3506 group A2 (304 / 1.4301), commonly supplied A2-70: good general corrosion resistance, largely non-magnetic, service range approx. -200 °C to +400 °C, subject to the property class and the joint. This page summarizes the grade data, its corrosion behavior in service, the comparable grades, and the sizes supplied.
Why Choose A2 Stainless Steel for Wedge-Lock Washer Pairs
The most common stainless group for indoor and general outdoor fasteners. For wedge-lock washer pairs, this matters when good general corrosion resistance is the primary requirement.
Mechanical & Physical Properties
| Grade designation | ISO 3506 group A2 (304 / 1.4301), commonly supplied A2-70 |
|---|---|
| Magnetic response | Largely non-magnetic |
| Service temperature | approx. -200 °C to +400 °C, subject to the property class and the joint |
| Corrosion characteristic | Good general corrosion resistance |
Galvanic & Galling Considerations
For stainless wedge-lock washer pairs the compatibility question is galvanic rather than galling: joined to aluminum or galvanized steel in wet service, stainless drives corrosion of the less-noble metal. Isolate with a coating, sleeve or non-conductive washer where the joint sees moisture. Note also that stainless is softer than hardened carbon steel, so where the part carries a wear or shear duty, check the load against the grade before substituting.
Comparable Grades
For Wedge-Lock Washer Pairs, the alternative stainless grade is A4 (316). A2 (304) covers general indoor and outdoor service. A4 (316) adds molybdenum, which is what buys the chloride resistance for marine and de-icing-salt exposure. Where strength matters more than corrosion, plated alloy steel in class 8.8 or 10.9 is the swap to make.
Using Stainless Fasteners in Aluminum
Stainless steel is more noble than aluminum, so with an electrolyte present — rain, condensation, salt spray — the aluminum becomes the anode and corrodes at the joint. Area ratio decides how bad it gets: a small stainless fastener in a large aluminum section is normally acceptable, a large stainless fastener in thin aluminum is not. Where the joint gets wet, isolate the metals with a coated or nylon washer and a sealant, or specify an aluminum or coated fastener instead.
Sizes of Wedge-Lock Washer Pairs Available in A2 Stainless Steel
| For bolt size | Inner diameter d1 (mm) | Outer diameter d2 (mm) | Thickness of pair t (mm) | Cam angle | Fits property class up to | Material | Re-use |
|---|---|---|---|---|---|---|---|
| M6 | 6.4 | 10.8 | 2.5 | approx. 12u00b0 | 12.9 | Hardened steel, Delta Protekt | Yes, teeth permitting |
| M8 | 8.7 | 13.5 | 3.4 | approx. 12u00b0 | 12.9 | Hardened steel, Delta Protekt | Yes, teeth permitting |
| M10 | 10.7 | 16.6 | 3.4 | approx. 12u00b0 | 12.9 | Hardened steel, Delta Protekt | Yes, teeth permitting |
| M12 | 13.0 | 19.5 | 4.0 | approx. 12u00b0 | 12.9 | Hardened steel, Delta Protekt | Yes, teeth permitting |
| M16 | 17.0 | 25.4 | 4.6 | approx. 12u00b0 | 12.9 | Hardened steel, Delta Protekt | Yes, teeth permitting |
| M20 | 21.4 | 30.7 | 5.2 | approx. 12u00b0 | 12.9 | Hardened steel, Delta Protekt | Yes, teeth permitting |
