A2 Stainless Steel Conical Spring Washers (HV) combine the dimensional form of DIN 6796 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 Conical Spring Washers (HV)
The most common stainless group for indoor and general outdoor fasteners. For conical spring washers (hv), 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 conical spring washers (hv) 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 Conical Spring Washers (HV), 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.
Using Stainless Fasteners in Aluminum
Stainless steel is more noble than aluminum, so in the presence of an electrolyte — rain, condensation, salt spray — the aluminum becomes the anode and corrodes at the joint. The effect is driven by the area ratio: a small stainless fastener in a large aluminum section is normally acceptable, while a large stainless fastener in thin aluminum is not. Where the joint is wet, isolate the two metals with a coated or nylon washer and a sealant, or specify an aluminum or coated fastener instead.
Sizes of Conical Spring Washers (HV) Available in A2 Stainless Steel
| Size | Inner diameter d1 (mm) | Outer diameter d2 (mm) | Thickness s (mm) | Height h max (mm) | Height h min (mm) | Reference standard |
|---|---|---|---|---|---|---|
| M2 | 2.2 | 5 | 0.4 | 0.6 | 0.5 | DIN 6796 |
| M2.5 | 2.7 | 6 | 0.5 | 0.72 | 0.61 | DIN 6796 |
| M3 | 3.2 | 7 | 0.6 | 0.85 | 0.72 | DIN 6796 |
| M3.5 | 3.7 | 8 | 0.8 | 1.06 | 0.92 | DIN 6796 |
| M4 | 4.3 | 9 | 1 | 1.3 | 1.12 | DIN 6796 |
| M5 | 5.3 | 11 | 1.2 | 1.55 | 1.35 | DIN 6796 |
| M6 | 6.4 | 14 | 1.5 | 2 | 1.7 | DIN 6796 |
| M7 | 7.4 | 17 | 1.75 | 2.3 | 2 | DIN 6796 |
| M8 | 8.4 | 18 | 2 | 2.6 | 2.4 | DIN 6796 |
| M10 | 10.5 | 23 | 2.5 | 3.2 | 2.8 | DIN 6796 |
| M12 | 13 | 29 | 3 | 3.95 | 3.43 | DIN 6796 |
| M14 | 15 | 35 | 3.5 | 4.65 | 4.04 | DIN 6796 |
| M16 | 17 | 39 | 4 | 5.25 | 4.58 | DIN 6796 |
| M18 | 19 | 42 | 4.5 | 5.6 | 5.08 | DIN 6796 |
| M20 | 21 | 45 | 5 | 6.4 | 5.6 | DIN 6796 |
| M22 | 23 | 49 | 5.5 | 7.05 | 6.15 | DIN 6796 |
| M24 | 25 | 56 | 6 | 7.75 | 6.77 | DIN 6796 |
| M27 | 28 | 60 | 6.5 | 8.35 | 7.3 | DIN 6796 |
| M30 | 31 | 70 | 7 | 9.2 | 8 | DIN 6796 |
