A2 Stainless Steel PTFE Flat Washers are supplied to DIN 125 A. The grade provides good general corrosion resistance and is largely non-magnetic; the practical service range is approx. -200 °C to +400 °C, subject to the property class and the joint. Property data, grade comparison and the full size table follow.
Why Choose A2 Stainless Steel for PTFE Flat Washers
The most common stainless group for indoor and general outdoor fasteners. For ptfe flat washers, 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 |
Corrosion Behavior in Service
A2 (304) gives excellent atmospheric and most-water corrosion resistance and is the most common stainless for PTFE Flat Washers in indoor and general outdoor service. In chloride-bearing environments (marine air, road salt, swimming pools) consider stepping up to A4 (316).
Galvanic & Galling Considerations
Two important notes for stainless ptfe flat washers: (1) stainless can gall on stainless threads under load — use a thread lubricant or anti-galling compound, especially for M6 and below; (2) when joined to aluminum or galvanized steel, stainless can drive galvanic corrosion of the less-noble metal in wet service — isolate with a coating or sleeve where appropriate.
Using Stainless Fasteners in Aluminum
Expect the aluminum to corrode, not the fastener — stainless sits higher in the galvanic series, so the aluminum is the one that gives up material. A small fastener in a thick section spreads the loss over a large area and is usually fine; a large fastener in thin sheet concentrates it and is not. Keep water out of the joint, or isolate the two metals with a nylon or coated washer and a sealant.
Sizes of PTFE Flat Washers Available in A2 Stainless Steel
| Thread size | Inner diameter d1 (mm) | Outer diameter d2 (mm) | Thickness s (mm) | Temperature range (deg C) | Reference standard |
|---|---|---|---|---|---|
| M3 | 3.2 | 7 | 0.5 | -200 to +260 | DIN 125 A series |
| M4 | 4.3 | 9 | 1.0 | -200 to +260 | DIN 125 A series |
| M5 | 5.3 | 10 | 1.0 | -200 to +260 | DIN 125 A series |
| M6 | 6.4 | 12 | 1.5 | -200 to +260 | DIN 125 A series |
| M8 | 8.4 | 16 | 2.0 | -200 to +260 | DIN 125 A series |
| M10 | 10.5 | 20 | 2.0 | -200 to +260 | DIN 125 A series |
| M12 | 13 | 24 | 2.5 | -200 to +260 | DIN 125 A series |
| M16 | 17 | 30 | 3.0 | -200 to +260 | DIN 125 A series |
| M20 | 21 | 37 | 3.0 | -200 to +260 | DIN 125 A series |
Dimensions are independent of the material: the table above lists the sizes supplied, and on this page every one of them is quoted in A2 Stainless Steel. The catalogue's default material column has been omitted here so it cannot be read as contradicting that.
Custom manufacturing · Made to drawing
Need this washer in a grade that is not listed?
A2 Stainless Steel is one of the grades the catalog describes. Bore, outside diameter, thickness, temper and finish are the variables here — there is no thread to specify, so the fit and the bearing area are what the drawing has to pin down. Made by stamping or punching.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
