Invar 36,Super Invar 32-5 Sheet,UNS K93050,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

### **Product Datasheet: Invar 36 & Super Invar 32-5 (UNS K93050) Sheet** #### **1. Overview** **Invar 36** and **Super Invar 32-5** are nickel-iron alloys specifically engineered to exhibit an exceptionally **Low Coefficient of Thermal Expansion (CTE)**. This unique property, known as the "Invar Effect," makes them indispensable in applications where dimensional stability is paramount under varying thermal conditions. * **Invar 36** is the industry-standard alloy, providing a near-zero CTE around room temperature. * **Super Invar 32-5** is a superior-grade alloy with a 5% Cobalt addition, offering an ultra-low CTE that is approximately three times lower than standard Invar 36 at room temperature. Supplied in **sheet form**, this material is the preferred choice for manufacturing precision components that require minimal thermal movement. The Unified Numbering System (UNS) designation **K93050** serves as a general classification for these low-expansion iron-nickel alloys. #### **2. Chemical Composition (Weight %)** | Element | Invar 36 (ASTM F1684) | Super Invar 32-5 (ASTM F1684) | | :--- | :--- | :--- | | **Nickel (Ni)** | 36.0% | 32.0% | | **Iron (Fe)** | Balance | Balance | | **Cobalt (Co)** | - | 5.0% | | **Carbon (C)** | ≤ 0.05% | ≤ 0.05% | | **Manganese (Mn)**| ≤ 0.35% | ≤ 0.35% | | **Silicon (Si)** | ≤ 0.25% | ≤ 0.25% | | **Chromium (Cr)**| ≤ 0.20% | ≤ 0.20% | | **Sulfur (S)** | ≤ 0.02% | ≤ 0.02% | | **Phosphorus (P)**| ≤ 0.02% | ≤ 0.02% | #### **3. Physical & Mechanical Properties (Typical for Annealed Sheet)** | Property | Invar 36 | Super Invar 32-5 | | :--- | :--- | :--- | | **Coefficient of Thermal Expansion (CTE)** | **1.6 x 10⁻⁶/°C**
(20°C to 100°C) | **0.6 x 10⁻⁶/°C**
(20°C to 100°C) | | **Density** | 8.11 g/cm³ | 8.13 g/cm³ | | **Melting Point** | ~1427°C (2600°F) | ~1430°C (2610°F) | | **Curie Temperature** | ~279°C (535°F) | ~310°C (590°F) | | **Thermal Conductivity** | 10.5 W/m·K (at 23°C) | 10.5 W/m·K (at 23°C) | | **Specific Heat** | 515 J/kg·K (at 20°C) | 515 J/kg·K (at 20°C) | | **Tensile Strength** | 517 MPa (75 ksi) | 552 MPa (80 ksi) | | **Yield Strength (0.2% Offset)**| 276 MPa (40 ksi) | 345 MPa (50 ksi) | | **Elongation (in 2")** | 30% | 25% | | **Modulus of Elasticity** | 141 GPa (20.5 x 10⁶ psi) | 141 GPa (20.5 x 10⁶ psi) | | **Hardness (Rockwell B)** | 75 HRB | 80 HRB | #### **4. International Standards** These alloys are specified in several international standards for composition and sheet products. | Standard Type | Invar 36 | Super Invar 32-5 | | :--- | :--- | :--- | | **Material Standard** | ASTM F1684 | ASTM F1684 | | **Unified Numbering System (UNS)** | **K93600** | **K94600** | | **European Standard (EN)** | Ni36 (1.3912) | Ni32Co5Cu (1.3981) | | **Japanese Standard (JIS)** | NILO 36 (Cactus 7) | - | *Note: UNS K93050 is a general prefix. For precise specification, use **UNS K93600** for Invar 36 and **UNS K94600** for Super Invar. Sheet dimensions and tolerances are typically supplied to standards like ASTM A480/A480M.* #### **5. Product Applications** Invar sheet is critical for high-precision applications requiring maximum dimensional stability: * **Aerospace & Defense:** Precision shadow masks, satellite baffles, lightweight optical mounts, and face sheets for stable composite structures. * **Semiconductor Manufacturing:** Reticle masks, EUV lithography components, vacuum chamber liners, and wafer stage components. * **Precision Instrumentation:** Diaphragms, bellows, laser housing components, and scientific instrument frames. * **Cryogenics:** Seals and gaskets for cryogenic storage tanks and transfer systems. * **Electronics & Telecommunications:** Lead frames and substrates for high-power electronics where thermal mismatch must be avoided. #### **6. Key Advantages of Sheet Form** * **Superior Dimensional Stability:** Maintains precise shape and flatness across extreme temperature gradients, essential for photomasks and optical components. * **Excellent Formability:** The sheet can be stamped, deep-drawn, and formed into complex shapes, making it ideal for bellows and diaphragms. * **Lightweight & Rigid:** Offers an excellent strength-to-weight ratio for applications where every gram counts, such as in aerospace structures. * **Good Weldability:** Can be readily welded using TIG, MIG, or laser techniques with matching filler metals to create complex assemblies. --- **Disclaimer:** The values provided are typical and for informational purposes. Specific properties for a given sheet lot should be confirmed with the manufacturer's certified test report. Forming and welding may require specialized procedures and post-process heat treatment.

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 2436 gallon liquid totes Special package is available on request.