Hangbo Alloy Group
Shanghai · Est. 2012
UNS N30000 / W.Nr. — — Chemical composition, mechanical properties, and corrosion resistance data for engineers and procurement professionals.
Springex 300 is a high-strength nickel-iron-chromium-molybdenum alloy strip specifically developed for spring applications requiring excellent corrosion resistance and high fatigue strength. The alloy maintains its spring properties at elevated temperatures up to 400°C.
The chemical composition of Springex 300 is carefully controlled to achieve its unique combination of properties and performance characteristics.
| Element | Min % | Max % |
|---|---|---|
| Nickel (Ni) | 35.0 | 38.0 |
| Iron (Fe) | Balance | Balance |
| Chromium (Cr) | 15.0 | 17.0 |
| Molybdenum (Mo) | 6.0 | 8.0 |
| Cobalt (Co) | — | 2.0 |
| Carbon (C) | — | 0.06 |
| Manganese (Mn) | — | 1.0 |
| Titanium (Ti) | — | 0.50 |
The mechanical properties of Springex 300 vary depending on product form and heat treatment condition. The data below represents typical values for solution-annealed material.
| Property | Value |
|---|---|
| Tensile Strength | 1400 MPa |
| Yield Strength (0.2% offset) | 1100 MPa |
| Elongation in 2 inches | 12% |
| Density | 8.20 g/cm3 |
| Melting Point | 1390 °C |
| Max Service Temperature | 400 °C |
Good resistance to atmospheric corrosion and mild chemical environments. The chromium and molybdenum content provides moderate resistance to pitting and crevice corrosion. Suitable for applications in marine and industrial atmospheres.
The unique combination of properties makes Springex 300 suitable for a wide range of demanding applications:
Hangbo Alloy Group manufactures and supplies Springex 300 in the following product forms, conforming to ASTM, AMS, and ASME specifications:
| Standard | Description |
|---|---|
| ASTM A313 | Stainless Spring Wire |
| AMS 5512 | Strip |
| DIN 17224 | Spring Steel |
| JIS G4314 | Japanese Standard |
| SAE AMS 5512 | Aerospace Material |
| ISO 6931-1 | Spring Strip |
Springex 300 reaches its 1400 MPa tensile / 1100 MPa yield figure in the cold-worked plus aged condition. Selecting the right temper and stress-relief cycle is what separates a spring that holds its load from one that relaxes in service.
| Condition | Tensile (MPa) | Typical use |
|---|---|---|
| Solution annealed | ≈ 850 | Forming, deep drawing |
| Cold worked (spring temper) | 1200–1400 | Flat springs, clips, diaphragms |
| Cold worked + aged 480 °C | 1350–1450 | High-load springs to 400 °C |
After severe forming, stress-relieve at 450–500 °C for 1–2 hours. This restores elasticity without over-ageing. Full ageing at higher temperature raises strength but reduces fatigue life, so match the cycle to whether load retention or cycle count matters more.
Springex 300 sits between them: better corrosion resistance and relaxation behaviour than 17-7 PH, at a lower material cost than Inconel X-750, with a practical service ceiling around 400 °C.
Welding is possible with matching filler but the heat-affected zone loses the cold-worked temper. For critical springs, form and heat-treat the finished part instead of welding assemblies.
Precision strip from 0.05 mm upward, plus wire and bar. Tight thickness tolerance and controlled camber are available for diaphragm and bellows work.
UNS N30000: 35-38% nickel, 15-17% chromium, 6-8% molybdenum, up to 2% cobalt, iron balance and 0.06% max carbon.
Tensile about 1400 MPa, yield about 1100 MPa and 12% elongation in the cold-worked/aged spring condition.
It combines high strength with corrosion resistance and retains spring properties to about 400 °C, resisting relaxation in service.
Corrosion-resistant springs, washers, seals and fasteners in marine and industrial atmospheres.
Strip and foil primarily, with bar and wire available in the temper required for spring fabrication.
Its higher nickel and molybdenum give better corrosion and fatigue resistance than conventional 300-series spring steel.
Hangbo Alloy Group maintains extensive inventory of Springex 300 in all standard product forms. We can provide mill test certificates, third-party inspection reports (SGS, TUV), and custom processing services.
For quotations, material certifications, or technical consultation, contact our sales team or call +86 166 2109 2936. We typically respond within 10 minutes.
Request a quotation for Springex 300 round bars, tubes, plates, or custom products. We stock standard sizes and accept custom orders.