Description (English)
Shanghai Vertex Alloy Co., Ltd (Vertex Alloy) supplies Invar 36 alloy tube (UNS K93600 / W.Nr 1.3912 / FeNi36, equivalent to Chinese GB 4J36) — the 36% nickel-iron low expansion alloy with the lowest coefficient of thermal expansion of any commercial metal: only 1.2–1.5 × 10⁻⁶/K between 20–100°C, roughly one-tenth that of carbon steel. The alloy retains good strength and toughness from cryogenic temperatures (-250°C) up to ~260°C, making it the standard material for LNG piping and membrane tank systems, laser resonator tubes, optical support structures, waveguides, standards of length and aerospace composite tooling. Supplied as seamless and welded tube to ASTM F1684, OD 6–219 mm with 0.5–15 mm wall, annealed or hard drawn, with EN 10204 3.1 certificates; precision capillary tube available on request. Note: Invar® is a registered trademark of Aperam Alloys Imphy — we supply the equivalent generic alloy. Contact us for the latest stock and pricing.
Size Range
- OD: 6–219 mm
- WT:0.5–15 mm
- L: Up to 6,000 mm, cut-to-length available
Grade Specification
| System | Value |
|---|---|
| USA (UNS) | K93600 (also K93601 / K93603) |
| Germany (W.Nr) | 1.3912 / FeNi36 |
| China (GB) | 4J36 |
| Commercial Names | Invar 36 (Aperam Imphy), Nilo 36, Pernifer 36 |
| Product Standard | ASTM F1684 |
| Reference Standards | ASTM B753, SEW 385, NF A54-301 |
Chemical Composition
| Element | Value |
|---|---|
| NI | 35.0–37.0 |
| C | ≤ 0.05 |
| Mn | ≤ 0.60 |
| Si | ≤ 0.35 |
| Co | ≤ 0.50 |
| Cr | ≤ 0.50 |
| P | ≤ 0.025 |
| S | ≤ 0.025 |
| Fe | Balance |
Mechanical Properties
| Property | Value |
|---|---|
| Tensile Strength | 450–585 MPa |
| Yield Strength (0.2%) | 240–275 MPa |
| Elongation (50 mm) | 30–45% |
| Hardness | 140–160 HB |
| Cryogenic Toughness | Good down to −250°C |
Physical Properties
| Property | Unit | Value |
|---|---|---|
| Density | - | 8.11 g/cm³ |
| Melting Point | - | ≈ 1,430°C |
| CTE (20–100°C) | - | 1.2–1.5 × 10⁻⁶ /K |
| CTE (20–200°C) | - | ≈ 2.6 × 10⁻⁶ /K |
| Curie / Inflection Point | - | ≈ 220–230°C |
| Thermal Conductivity (20°C) | - | 10.0–10.5 W/(m·K) |
| Magnetic | - | Yes (below Curie point) |
Applications
- LNG / Cryogenic:LNG tank & piping systems;Membrane tank support components;
- Laser & Optics: Laser resonator tubes; Optical benches, telescope structures
- Precision Instruments:Standards of length, metrology devices;Waveguide tubes
- Aerospace:Satellite structures; Composite tooling & molds
- Electronics: Thermostat rods, shadow masks
- Scientific: Cryogenic research apparatus