Material page for thread forming screws for plastic in A2 Stainless Steel (ISO 3506 group A2 (304 / 1.4301), commonly supplied A2-70). The sizes below are the ones we supply; there is no published dimensional standard for this article, so the table rather than a standard number is what to quote. Corrosion behaviour is good general corrosion resistance and the service range is approx. -200 °C to +400 °C, subject to the property class and the joint.
Why Choose A2 Stainless Steel for Thread Forming Screws for Plastic
The most common stainless group for indoor and general outdoor fasteners. For thread forming screws for plastic, 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 Thread Forming Screws for Plastic 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 Thread Forming Screws for Plastic, 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 Thread Forming Screws for Plastic Available in A2 Stainless Steel
| Thread size | Pitch (mm) | Head diameter dk (mm) | Head height k (mm) | Boss hole, amorphous (mm) | Boss hole, filled (mm) | Common length range (mm) | Reference standard |
|---|---|---|---|---|---|---|---|
| 2.0 | 0.9 | 4.0 | 1.6 | 1.65 | 1.75 | 5~16 | Industry standard |
| 2.5 | 1.1 | 5.0 | 2.0 | 2.05 | 2.15 | 5~20 | Industry standard |
| 3.0 | 1.3 | 6.0 | 2.4 | 2.45 | 2.60 | 6~25 | Industry standard |
| 3.5 | 1.5 | 7.0 | 2.8 | 2.85 | 3.00 | 8~30 | Industry standard |
| 4.0 | 1.7 | 8.0 | 3.1 | 3.25 | 3.45 | 8~35 | Industry standard |
| 5.0 | 2.1 | 10.0 | 3.8 | 4.10 | 4.30 | 10~40 | Industry standard |
| 6.0 | 2.5 | 12.0 | 4.6 | 4.90 | 5.15 | 12~50 | Industry standard |
Dimensions are independent of the material: every size above is available in A2 Stainless Steel.
Custom manufacturing · Made to drawing
Need this screw in a grade that is not listed?
A2 Stainless Steel is one of the grades the catalog describes. A non-standard screw is quoted from the drawing; where one already exists in the catalog, the special is usually a variation on its tooling. Made by cold heading or warm forging.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
