A4 Stainless Steel Phillips Countersunk Screws pairs the standard ISO 7046 / DIN 965 with a A4 Stainless Steel base material. The sections below cover why engineers select this grade for phillips countersunk screws, its corrosion and temperature behavior, and the sizes available.
Why Choose A4 Stainless Steel for Phillips Countersunk Screws
Specified for marine, coastal and chemical applications. For phillips countersunk screws, this matters when superior, including marine and chloride environments is the primary requirement.
Mechanical & Physical Properties
| Grade designation | A4-80 (316) |
|---|---|
| Magnetic response | Largely non-magnetic |
| Service temperature | approx. -200 °C to +400 °C |
| Corrosion characteristic | Superior, including marine and chloride environments |
Galvanic & Galling Considerations
Two important notes for stainless phillips countersunk screws: (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 Phillips Countersunk Screws, the alternative stainless grade is A2 (304). 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.
Sizes of Phillips Countersunk Screws Available in A4 Stainless Steel
| Size | Pitch (mm) | Head diameter dk (mm) | Head height k (mm) | Cross recess | Countersink angle (deg) | Reference standard |
|---|---|---|---|---|---|---|
| M1.6 | 0.35 | 3.0 | 0.96 | PH0 | 90 | ISO 7046 / DIN 965 |
| M2 | 0.4 | 3.8 | 1.2 | PH1 | 90 | ISO 7046 / DIN 965 |
| M2.5 | 0.45 | 4.7 | 1.5 | PH1 | 90 | ISO 7046 / DIN 965 |
| M3 | 0.5 | 5.6 | 1.65 | PH1 | 90 | ISO 7046 / DIN 965 |
| M3.5 | 0.6 | 6.5 | 1.93 | PH2 | 90 | ISO 7046 / DIN 965 |
| M4 | 0.7 | 7.5 | 2.2 | PH2 | 90 | ISO 7046 / DIN 965 |
| M5 | 0.8 | 9.2 | 2.5 | PH2 | 90 | ISO 7046 / DIN 965 |
| M6 | 1.0 | 11.0 | 3.0 | PH3 | 90 | ISO 7046 / DIN 965 |
| M8 | 1.25 | 14.5 | 4.0 | PH3 | 90 | ISO 7046 / DIN 965 |
| M10 | 1.5 | 18.0 | 5.0 | PH4 | 90 | ISO 7046 / DIN 965 |