Invar 36,Nilo 36 Bar(Round bar, Flat bar),UNS K93601,E FORU

British Specs:，American Specs: ASTM F1684 MIL-S-16598 Tooling plate ASTM B388 Sheet & strip ASTM B753 K93050 Free-cut Invar，German Specs:WS 1.3912

### **Invar 36 / Nilo 36 Bar (Round Bar & Flat Bar) - UNS K93601 Product Introduction** #### **Overview** Invar 36, commercially known as **Nilo 36**, is a nickel-iron low expansion alloy registered under **UNS K93601**. The bar form, available as both round bars and flat bars, provides versatile stock material for machining and fabricating components that require exceptional dimensional stability across temperature variations. These product forms are essential for creating structural elements, mounting components, and precision parts where thermal growth must be minimized. #### **Key Characteristics** - **Ultra-Low Thermal Expansion:** CTE typically **1.6 × 10⁻⁶/°C** (20-100°C) - **Excellent Machinability:** Good machining characteristics in various tempers - **High Strength-to-Weight Ratio:** Suitable for structural applications - **Dimensional Stability:** Maintains precise dimensions under thermal cycling - **Good Weldability:** Compatible with common welding techniques --- #### **1. Chemical Composition** | Element | Content (%) | |---------|-------------| | **Nickel (Ni)** | 35.0 - 37.0 | | **Iron (Fe)** | Balance | | **Carbon (C)** | 0.10 max | | **Manganese (Mn)** | 0.50 max | | **Silicon (Si)** | 0.30 max | | **Phosphorus (P)** | 0.025 max | | **Sulfur (S)** | 0.025 max | | **Cobalt (Co)** | 0.50 max | | **Chromium (Cr)** | 0.25 max | --- #### **2. Physical Properties** | Property | Value | |----------|-------| | **Density** | 8.13 g/cm³ | | **Melting Point** | 1425°C (2600°F) | | **Thermal Expansion Coefficient** | **1.6 × 10⁻⁶/°C** (20-100°C) | | **Thermal Conductivity** | 10.5 W/m·K | | **Specific Heat Capacity** | 515 J/kg·K | | **Modulus of Elasticity** | 145 GPa | | **Magnetic Properties** | Ferromagnetic below 230°C | --- #### **3. Mechanical Properties (Annealed Condition)** | Property | Round Bar | Flat Bar | |----------|-----------|----------| | **Tensile Strength** | 480-550 MPa | 470-540 MPa | | **Yield Strength (0.2%)** | 280-350 MPa | 270-340 MPa | | **Elongation** | 30-35% | 30-40% | | **Hardness** | 75-85 HRB | 70-80 HRB | --- #### **4. Product Applications** **Round Bar Applications:** - **Precision Shafts and Spindles:** For measuring instruments and optical equipment - **Structural Components:** In satellite and aerospace structures - **Machine Tool Elements:** Guide rods and precision pins - **Laboratory Equipment:** Support columns and structural members **Flat Bar Applications:** - **Mounting Rails and Bases:** For optical systems and instrumentation - **Structural Framing:** In precision equipment and scientific instruments - **Brackets and Supports:** For cryogenic and high-temperature applications - **Machine Components:** Ways and guide rails --- #### **5. International Standards** | Standard Body | Standard Number | Description | |---------------|-----------------|-------------| | **ASTM** | ASTM F1684 | Standard Specification for Iron-Nickel and Cobalt-Nickel Alloy Bar | | **AMS** | AMS 7725 | Aerospace Material Specification | | **EN** | EN 1.3912 | European Standard for Bar Products | | **DIN** | DIN 1.3912 | German Standard | | **JIS** | JIS NCF 2 | Japanese Industrial Standard | --- #### **6. Available Forms & Sizes** **Round Bar:** - **Diameter Range:** 3mm to 300mm - **Length:** Standard 3-4 meters, cut-to-length available - **Surface Finish:** Hot finished, cold drawn, centerless ground **Flat Bar:** - **Thickness:** 3mm to 100mm - **Width:** 10mm to 300mm - **Length:** Standard 3-4 meters, cut-to-length available --- #### **7. Fabrication Characteristics** **Machining:** - Use positive rake angles and sharp tools - Recommended cutting speeds: 20-35 m/min - Use sulfurized or chlorinated cutting fluids - Account for work hardening during processing **Welding:** - Compatible with GTAW (TIG) and GMAW (MIG) processes - Use matching filler metal (UNS K93601) - Post-weld heat treatment recommended **Heat Treatment:** - **Annealing:** 830-880°C, rapid cool - **Stress Relieving:** 425-540°C, 1-2 hours --- #### **Conclusion** Nilo 36 Bar (UNS K93601) in both round and flat forms offers exceptional dimensional stability combined with good mechanical properties and manufacturability. These product forms are particularly valuable for applications in precision instrumentation, aerospace structures, and scientific equipment where thermal expansion must be minimized. The availability in various sizes and conditions makes Nilo 36 bars suitable for both prototyping and production applications across multiple industries.

Packing of Standard Packing: Typical bulk packaging includes palletized plastic 5 gallon/25 kg. pails, fiber and steel drums to 1 ton super sacks in full container (FCL) or truck load (T/L) quantities. Research and sample quantities and hygroscopic, oxidizing or other air sensitive materials may be packaged under argon or vacuum. Solutions are packaged in polypropylene, plastic or glass jars up to palletized 2406 gallon liquid totes Special package is available on request.