Invar 36,Alloy 36 Other/Similar Specs,UNS K93600,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 / Alloy 36 Forgings (UNS K93600) - Product Introduction** #### **Overview** Invar 36, also known as Alloy 36 or UNS K93600, is a nickel-iron alloy famous for its exceptionally low Coefficient of Thermal Expansion (CTE). **Alloy 36 Forgings** are components shaped by the industrial process of forging, which involves applying compressive forces to deform the material into high-strength parts with superior grain flow. This manufacturing method is ideal for creating robust, reliable components that must maintain dimensional stability under severe thermal and mechanical stress. #### **Key Characteristics of Alloy 36 Forgings** * **Exceptional Dimensional Stability:** The CTE is typically about **1.6 x 10⁻⁶/°C** between 20°C and 100°C, ensuring minimal size change with temperature fluctuations. * **Superior Mechanical Integrity:** The forging process refines the grain structure, eliminates porosity, and improves toughness, resulting in higher strength and better fatigue resistance compared to cast or fabricated parts. * **Excellent Structural Homogeneity:** Forgings provide a continuous grain pattern, leading to consistent mechanical properties and enhanced reliability throughout the component. * **Good Machinability and Weldability:** Can be machined to precise tolerances and welded using standard techniques, though post-weld heat treatment is often recommended. --- #### **1. Chemical Composition** The unique properties of Invar 36 are achieved through a tightly controlled chemical composition. | Element | Content (%) | | :--- | :--- | | **Nickel (Ni)** | 36.0% min | | **Iron (Fe)** | Balance | | **Carbon (C)** | 0.10% max | | **Manganese (Mn)** | 0.60% max | | **Silicon (Si)** | 0.40% 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 / Description | | :--- | :--- | | **Density** | 8.11 g/cm³ (0.293 lb/in³) | | **Melting Point** | ~1427°C (2600°F) | | **Thermal Expansion Coefficient (CTE)** | **1.6 x 10⁻⁶/°C** (20-100°C)
2.7 x 10⁻⁶/°C (20-300°C) | | **Thermal Conductivity** | 10.5 W/m·K (at 20°C) | | **Specific Heat** | 515 J/kg·K (at 20°C) | | **Magnetic Properties** | Ferromagnetic at room temperature. Becomes non-magnetic (paramagnetic) above its Curie temperature of ~279°C (534°F). | --- #### **3. Typical Mechanical Properties (Forged & Annealed)** *Properties are for finished, annealed forgings to ensure optimal dimensional stability and stress relief.* | Property | Value | | :--- | :--- | | **Tensile Strength** | 517 - 585 MPa (75 - 85 ksi) | | **Yield Strength (0.2% Offset)** | 276 - 345 MPa (40 - 50 ksi) | | **Elongation (in 2")** | 25% - 35% | | **Reduction of Area** | 50% - 65% | | **Hardness (Rockwell B)** | 75 - 95 HRB | --- #### **4. Product Applications** Alloy 36 Forgings are specified for high-integrity applications where both thermal stability and structural reliability are non-negotiable. * **Aerospace & Defense:** * **Engine Components:** Mounting rings, casings, and structural supports for jet engines where high temperatures and stresses are present. * **Satellite & Spacecraft Structures:** Critical frames, optical benches, and mirror mounts that require absolute dimensional stability in the thermal vacuum of space. * **Missile Guidance Systems:** Housings for precision guidance systems that must resist thermal deformation. * **Semiconductor Manufacturing:** * **Chamber Components:** Large, complex parts for etch and CVD chambers, such as showerheads and electrode supports, where thermal stability prevents particle generation and process drift. * **Precision Stages:** Bases and frames for lithography equipment. * **Energy & Power Generation:** * **Turbine Components:** Seals, spacers, and rings in power generation turbines that undergo severe thermal cycling. * **Nuclear Instrumentation:** Core components and instrumentation housings where long-term stability is critical. * **Scientific & Research Equipment:** * **Particle Accelerators:** Precision-machined magnet cores and structural components where magnetic properties and stability are key. * **Large Telescope Structures:** Mirror cells and support frames that maintain optical alignment despite ambient temperature changes. --- #### **5. International Standards** Alloy 36 Forgings are produced in accordance with material and forging specifications that ensure their performance in critical applications. | Standard Body | Standard Designation | Title / Scope | | :--- | :--- | :--- | | **UNS** | **K93600** | Unified Numbering System | | **ASTM** | **ASTM A658 / A658M** | Standard Specification for **Wrought 36% Nickel-Iron Alloy Forgings** | | **AMS** | **AMS 7724** | Alloy 36, Forgings (Aerospace Material Specification) | | **ASME** | **SA-658 / SA-658M** | Equivalent to ASTM A658 for ASME Boiler and Pressure Vessel Code applications. | | **EN / Euronorm** | **EN 1.3912 / Ni36** | Wrought Steel Products | | **DIN** | **DIN 1.3912 / Ni36** | German Institute for Standardization | *Note: **ASTM A658** is the primary governing specification for Alloy 36 commercial forgings, while **AMS 7724** is used for aerospace applications. These standards specify stringent requirements for quality, testing, and inspection.* --- #### **Conclusion** Invar 36 (Alloy 36) Forgings, UNS K93600, represent the high-strength solution for applications demanding the ultimate in dimensional stability and structural integrity. The forging process enhances the innate properties of this low-expansion alloy, making it the material of choice for the most demanding components in aerospace, semiconductor, and energy sectors. When sourcing these critical forgings, verification of compliance with **ASTM A658** or **AMS 7724** is essential to guarantee performance in service.

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 2401 gallon liquid totes Special package is available on request.