Aluminium-indium Master Alloy，Aluminium indium Alloy，AlIn Alloy，E FORU

**Product Datasheet: Aluminium-Indium Master Alloy (Al-In Alloy)** **Version:** 1.0 | **Date:** 2025-04-02 --- ### **1. General Overview** Aluminium-Indium Master Alloy (Al-In Alloy) is a specialized alloy system that utilizes indium's unique properties to modify aluminium's characteristics, particularly in the areas of corrosion behavior, bearing properties, and surface engineering. Indium forms limited solid solution with aluminium and primarily exists as discrete particles or grain boundary films, significantly influencing electrochemical properties and tribological characteristics. --- ### **2. International Standards** Al-In master alloys are referenced in several international specifications: - **ASTM:** ASTM B179 (Standard Specification for Aluminum Alloys in Ingot and Molten Forms) - **ISO:** ISO 209-1 (Wrought aluminium and aluminium alloys) - **EN:** EN 1676 (Aluminium and aluminium alloys - Master alloys) - **AMS:** AMS 4488 (Aluminum Alloy Indium-containing Anodes) - **Typical Master Alloy Grades:** Al-5%In, Al-10%In, Al-20%In, Al-33%In (eutectic) --- ### **3. Chemical Composition (Weight %)** Typical composition ranges for Al-In master alloy: | Element | Content (%) | Role & Remarks | |---------------------|-------------------|------------------------------------------| | Indium (In) | 2.0 – 35.0 | Primary alloying element | | Tin (Sn) | 0 – 5.0 | Often co-added for synergistic effects | | Bismuth (Bi) | 0 – 3.0 | Optional addition for specific applications | | Iron (Fe) | ≤ 0.20 | Impurity control | | Silicon (Si) | ≤ 0.15 | Impurity control | | Other Impurities | ≤ 0.10 total | — | | Aluminium (Al) | Balance | Base metal | --- ### **4. Physical Properties** | Property | Value / Range | |---------------------------|-----------------------------------| | Density | 2.9 – 4.5 g/cm³ | | Melting Range | 156 – 660°C (In melts at 156°C) | | Eutectic Temperature | 156°C (Al-33%In) | | Eutectic Composition | 33% In, 67% Al | | Thermal Conductivity | 70 – 130 W/m·K | | Electrical Conductivity | 35 – 50 % IACS | | Vickers Hardness | 25 – 60 HV | | Electrochemical Potential | -0.9 to -1.1 V vs. SCE | --- ### **5. Key Characteristics & Advantages** - **Activation Properties:** Prevents passivation of aluminium in aqueous environments - **Low Melting Point:** Enables unique low-temperature processing routes - **Tribological Benefits:** Improves bearing and anti-galling properties - **Environmental Compatibility:** Replacement for mercury in some applications - **Cathodic Protection:** Enhanced performance in sacrificial anode applications - **Surface Engineering:** Enables specialized coating and plating processes --- ### **6. Product Applications** - **Sacrificial Anodes:** Marine and underground corrosion protection systems - **Bearing Alloys:** Improved anti-seizure properties in aluminium bearings - **Brazing Alloys:** Low-temperature aluminium brazing applications - **Electronic Packaging:** Thermal interface materials and solder applications - **Coating Systems:** Indium-containing aluminium coatings for corrosion protection - **Research & Development:** Experimental alloys for specialized applications - **Aerospace:** Selective applications requiring specific corrosion properties --- ### **7. Available Forms** - **Master Alloy:** Ingots, notch bars, granules - **Special Forms:** Powder, foil, wire for specific applications - **Anode Grades:** Optimized compositions for cathodic protection - **Standard Sizes:** 2–10 kg ingots --- ### **8. Technical Guidelines for Use** - **Addition Rate:** 0.01–5.0% In to the melt (depending on application) - **Melt Temperature:** 700–780°C - **Holding Time:** 20–40 minutes for homogenization - **Stirring:** Gentle mechanical stirring to prevent segregation - **Cooling Rate:** Controlled solidification for optimal microstructure - **Safety:** Adequate ventilation for fume control --- ### **9. Electrochemical Performance in Marine Applications** | In Content (%) | Current Capacity (A·h/kg) | Efficiency (%) | Closed Circuit Potential (V) | |----------------|---------------------------|----------------|------------------------------| | **0.01–0.05** | 2200–2400 | 85–90 | -1.05 to -1.08 | | **0.05–0.10** | 2400–2600 | 90–95 | -1.08 to -1.10 | | **0.10–0.20** | 2600–2800 | 95–98 | -1.10 to -1.15 | --- ### **10. Microstructural Characteristics** | Composition Range | Primary Structure | Indium Distribution | Key Features | |-------------------|-------------------|---------------------|--------------| | **<5% In** | Al solid solution | Grain boundaries | Activation | | **5–20% In** | Al + In particles | Discrete particles | Bearing properties | | **20–33% In** | Al + In networks | Continuous networks | Low melting | | **>33% In** | In-rich phases | Matrix phase | Special applications | --- ### **11. Quality Control Parameters** - Indium content consistency (±0.1%) - Homogeneous distribution verification - Low oxide content certification - Electrochemical performance testing (for anode grades) - Microstructural analysis for particle size distribution --- ### **12. Health, Safety & Handling** - **Toxicity:** Indium metal has low toxicity, but compounds require caution - **Dust Control:** Avoid inhalation of fine particles during processing - **Personal Protection:** Standard foundry PPE with respiratory protection for powders - **Ventilation:** Adequate fume extraction recommended - **Storage:** Dry, sealed containers to prevent oxidation - **Disposal:** Follow standard metal disposal protocols --- ### **13. Economic & Supply Considerations** - **Indium Source:** Primarily from zinc ore processing - **Cost Factors:** Moderate to high cost, subject to display industry demand - **Supply Chain:** Geopolitically sensitive with limited production - **Recycling:** Economically viable due to indium value - **Substitution:** Limited alternatives for activation properties --- ### **14. Specialized Applications Detail** **Marine Anodes:** - Activation prevents passivation in seawater - Consistent corrosion potential - High current capacity and efficiency **Bearing Alloys:** - Reduced friction coefficients - Improved anti-seizure properties - Compatibility with various lubricants --- ### **15. Research & Development Trends** - **Advanced Anodes:** Optimization for specific environmental conditions - **Composite Materials:** Al-In composites with enhanced properties - **Thermal Interface Materials:** Low thermal resistance applications - **Additive Manufacturing:** Specialty powders for 3D printing - **Green Alternatives:** Replacement for hazardous materials in various applications --- ### **Disclaimer** This information is provided for technical reference only. Properties and performance may vary based on specific application conditions and processing parameters. Al-In alloys require careful handling and process control to achieve desired properties. Users must conduct comprehensive testing and technical evaluation before implementation. Always follow appropriate safety guidelines and regulatory requirements. Consult with materials engineering specialists for critical applications in corrosion protection and tribological systems.

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 2296 gallon liquid totes Special package is available on request.