A2 Stainless Steel (A2-70 (304)) is the most common stainless grade for indoor and general outdoor fasteners. When compression spring are specified in this grade, the dimensions remain per ISO / DIN; the material determines corrosion behavior (good general corrosion resistance) and the service temperature range (approx. -200 °C to +400 °C). Both are covered below with the size table.
Why Choose A2 Stainless Steel for Compression Spring — ISO / DIN (Series 144)
The most common stainless grade for indoor and general outdoor fasteners. For compression spring — iso / din (series 144), this matters when good general corrosion resistance is the primary requirement.
Mechanical & Physical Properties
| Grade designation | A2-70 (304) |
|---|---|
| Magnetic response | Largely non-magnetic |
| Service temperature | approx. -200 °C to +400 °C |
| Corrosion characteristic | Good general corrosion resistance |
Galvanic & Galling Considerations
Two important notes for stainless compression spring — iso / din (series 144): (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 Compression Spring — ISO / DIN (Series 144), 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.
Sizes of Compression Spring — ISO / DIN (Series 144) Available in A2 Stainless Steel
| Wire dia d (mm) | Outer diameter De (mm) | Free length Lo (mm) | Rate k (N/mm) | Rated force Fn (N) | Material | Reference standard |
|---|---|---|---|---|---|---|
| 0.6 | 5.2 | 20 | 1.5 | 12 | Music wire / chrome silicon | DIN 2098 / GB/T 23934 |
| 0.8 | 6.6 | 25 | 2.5 | 22 | Music wire / chrome silicon | DIN 2098 / GB/T 23934 |
| 1.0 | 8.0 | 30 | 3.5 | 35 | Music wire / chrome silicon | DIN 2098 / GB/T 23934 |
| 1.2 | 10.4 | 40 | 6.0 | 55 | Music wire / chrome silicon | DIN 2098 / GB/T 23934 |
| 1.6 | 15.2 | 60 | 8.5 | 90 | Music wire / chrome silicon | DIN 2098 / GB/T 23934 |
| 2.0 | 20.0 | 80 | 18.0 | 165 | Music wire / chrome silicon | DIN 2098 / GB/T 23934 |
| 2.5 | 25.0 | 100 | 28.0 | 260 | Music wire / chrome silicon | DIN 2098 / GB/T 23934 |
| 3.0 | 30.0 | 120 | 45.0 | 450 | Music wire / chrome silicon | DIN 2098 / GB/T 23934 |
| 4.0 | 40.0 | 150 | 90.0 | 1000 | Music wire / chrome silicon | DIN 2098 / GB/T 23934 |
| 5.0 | 50.0 | 200 | 170 | 1900 | Music wire / chrome silicon | DIN 2098 / GB/T 23934 |