STATO 75

Oil tempered SiCrV-alloyed spring wire (according to EN 10270-2; 2011 FD SiCrV)

STATO 75 is especially intended for the manufacture of springs exposed to static or moderately high fatigue stresses. The material has good relaxation properties.

The wire is manufactured in sizes from Ø 2.00 mm to 7.00 mm. Other wire sizes on request.

Chemische Zusammensetzung

C (%) Si (%) Mn (%) P max. (%) S max. (%) Cr (%) V (%)
0,50 - 0,70 1,20 - 1,65 0,40 - 0,90 0,030 0,025 0,50 - 1,00 0,10 - 0,15

Mechanische Eigenschaften

1) Min No of twists in the torsion test, Nt, are to be agreed upon.

Für Runddraht

Durchmesser (mm) Toleranz (mm) Zugfestigkeit (N/mm²) Brucheinschnürung (min. %)
2,01 - 2,50 ±0,025 2160 - 2310 45
2,51 - 2,70 ±0,025 2110 - 2260 45
2,71 - 3,20 ±0,030 2110 - 2260 45
3,21 - 3,50 ±0,030 2110 - 2260 42
3,51 - 4,00 ±0,030 2060 - 2210 42
4,01 - 5,00 ±0,035 2060 - 2210 40
5,01 - 5,60 ±0,035 2010 - 2160 38
5,61 - 6,00 ±0,040 1960 - 2110 38
6,00 - 6,50 ±0,040 1960 - 2110 35
6,51 - 7,00 ±0,040 1960 - 2110 35

Oberflächenbeschaffenheiten

Oberflächenbeschaffenheit

Surface condition – end sample test
The wire is end sample tested by means of etch testing and binocular inspection as well as microscopical inspection of the material structure.

Max. permissible depth of partial surface decarburization and surface defects, 1.5% x wire diameter. No complete decarburization allowed.

Physikalische Eigenschaften

E und G Elastizitätsmodul

About 206 kN/mm2

E und G Schubmodul

About 79.5 kN/mm2

Empfehlungen

Wärmebehandlung

As soon as possible after coiling, the springs should be stress relieved.

Warmvorsetzen

After shot peening, the springs should be hot preset or stress relieved. In order to reach optimum fatigue and relaxation properties, the springs must be preset at an appropriate stress

Kugelstrahlen

In order to obtain optimum fatigue properties, the process time should be adjusted to get a complete treatment. Size of shots should be adapted to wire dimension, pitch and shot peening equipment. Shot peening of the inside of the spring coils is particularly critical.