A4 Stainless Steel (ISO 3506 group A4 (316 / 1.4401), commonly supplied A4-80) is specified for marine, coastal and chemical applications. When slotted set screws with cup point are specified in this grade, the dimensions remain per ISO 7436; the material determines corrosion behavior (superior, including marine and chloride environments) and the service temperature range (approx. -200 °C to +400 °C, subject to the property class and the joint). Both are covered below with the size table.
Why Choose A4 Stainless Steel for Slotted Set Screws with Cup Point
Specified for marine, coastal and chemical applications. For slotted set screws with cup point, this matters when superior, including marine and chloride environments is the primary requirement.
Mechanical & Physical Properties
| Grade designation | ISO 3506 group A4 (316 / 1.4401), commonly supplied A4-80 |
|---|---|
| Magnetic response | Largely non-magnetic |
| Service temperature | approx. -200 °C to +400 °C, subject to the property class and the joint |
| Corrosion characteristic | Superior, including marine and chloride environments |
Galvanic & Galling Considerations
Two important notes for stainless slotted set screws with cup point: (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.
Comparable Grades
For Slotted Set Screws with Cup Point, the alternative stainless grade is A2 (304). Choose A2 (304) for general use and A4 (316) wherever chlorides are present; the molybdenum in A4 is the whole difference. Remember that stainless is the corrosion answer, not the strength answer — for load, look at class 8.8 or 10.9 instead.
Using Stainless Fasteners in Aluminum
The galvanic couple here runs the wrong way: aluminum is the less noble metal, so it corrodes and the fastener does not. What governs the rate is the ratio of areas — a large anode and a small cathode is a tolerable combination, the reverse concentrates the attack into thin material around the hole. An isolating washer plus sealant breaks the circuit; where that is impractical, match the fastener to the substrate.
Sizes of Slotted Set Screws with Cup Point Available in A4 Stainless Steel
| Size | dz_min (mm) | dz_max (mm) | n_nom (mm) | n_min (mm) | n_max (mm) | t_min (mm) | t_max (mm) | Length range l (mm) | Reference standard |
|---|---|---|---|---|---|---|---|---|---|
| M1.6 | 0.55 | 0.8 | 0.25 | 0.31 | 0.45 | 0.56 | 0.74 | 2~8 | ISO 7436 |
| M2 | 0.75 | 1 | 0.25 | 0.31 | 0.45 | 0.64 | 0.84 | 2.5~10 | ISO 7436 |
| M2.5 | 0.95 | 1.2 | 0.4 | 0.46 | 0.6 | 0.72 | 0.95 | 3~12 | ISO 7436 |
| M3 | 1.15 | 1.4 | 0.4 | 0.46 | 0.6 | 0.8 | 1.05 | 3~16 | ISO 7436 |
| M3.5 | 1.45 | 1.7 | 0.5 | 0.56 | 0.7 | 0.96 | 1.21 | 4~20 | ISO 7436 |
| M4 | 1.75 | 2 | 0.6 | 0.66 | 0.8 | 1.12 | 1.42 | 4~20 | ISO 7436 |
| M5 | 2.25 | 2.5 | 0.8 | 0.86 | 1 | 1.28 | 1.63 | 5~25 | ISO 7436 |
| M6 | 2.75 | 3 | 1 | 1.06 | 1.2 | 1.6 | 2 | 6~30 | ISO 7436 |
| M8 | 4.7 | 5 | 1.2 | 1.26 | 1.51 | 2 | 2.5 | 8~40 | ISO 7436 |
| M10 | 5.7 | 6 | 1.6 | 1.66 | 1.91 | 2.4 | 3 | 10~50 | ISO 7436 |
| M12 | 7.7 | 8 | 2 | 2.06 | 2.31 | 2.8 | 3.6 | 12~60 | ISO 7436 |
Dimensions are independent of the material: every size above is available in A4 Stainless Steel.
Custom manufacturing · Made to drawing
Need this screw in a grade that is not listed?
A4 Stainless Steel is one of the grades the catalog describes. Lengths and thread lengths outside the standard table are the commonest request, followed by a drive the standard does not offer and a head marked with your own part number. Made by cold heading or warm forging.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
