IS 617:1994 is the Indian Standard (BIS) for aluminium and aluminium alloy ingots for remelting. IS 617 specifies primary aluminium and aluminium alloy ingots used as raw material for foundry remelting. It defines multiple purity grades from 99.0% to 99.9%+ aluminium content.
Specification for primary aluminium and aluminium alloy ingots for remelting, covering grades, chemical composition, and marking requirements.
Key reference values — verify against the current code edition / project specification.
| Reference | Value | Clause |
|---|---|---|
| Subject | Primary aluminium / alloy ingots for remelting | Scope |
| Grades | By purity / alloy chemical composition | Grades |
| Acceptance | Chemical composition limits per grade | QC |
| Use | Foundry feedstock for castings (IS 740 etc.) | Application |
| Read with | IS 740 (Al castings) / IS 733 / IS 737 | Cross-ref |
IS 617 is the specification for aluminium and aluminium alloy ingots for remelting — the source-grade aluminium used in foundries to cast architectural / industrial components. Aluminium has growing application in modern Indian construction (façade panels, window frames, roofing, signage).
Use IS 617 when: - Specifying aluminium for casting (window frames, balcony panels, decorative grilles) - Procuring aluminium ingots for in-house casting / fabrication - Quality verification of aluminium-based architectural components - Forensic investigation of aluminium failure (corrosion, cracking)
Aluminium grades per IS 617:
| Grade | Use | Composition | |---|---|---| | 1100 (A1) | Architectural / electrical | 99 % min Al | | 6063 / 6061 | Window/door frames, structural | Al-Mg-Si alloy | | 3003 | Roofing, panels | Al-Mn alloy | | 5052 / 5083 | Marine | Al-Mg alloy | | Al-Si casting alloy | Cast components | Various Al-Si |
Key aluminium properties: - Density: 2.7 g/cm³ (1/3 of steel) - Tensile strength: 70-310 MPa (varies by alloy + temper) - Corrosion resistance: excellent (natural oxide layer) - Workability: excellent (easily extruded, rolled, formed) - Cost (2026): ₹250-400/kg (raw); ₹400-1500/kg (anodised + finished)
Common aluminium applications in construction: - Window + door frames (extruded 6063 typical) - Cladding panels (anodised or PPG-coated 5xxx alloys) - Roofing sheets (corrugated) - Curtain wall systems - Composite panels (ACP — aluminium composite panel) - Hardware (handles, locks, closers) - Decorative trim - Signage
Surface finishes: - Mill finish — natural; protects via oxide layer; light grey - Anodised — electrochemically thickened oxide layer; coloured options; durable - Powder-coated — paint applied + cured; wide colour range - Polyester / fluoropolymer — high-end weatherproof finish - Mirror polished — for decorative
Corrosion + protection: - Aluminium has natural oxide layer (Al₂O₃) — passive - Vulnerable to: chloride attack (marine), galvanic corrosion (with steel / copper) - For coastal: anodised + paint over - For galvanic prevention: dielectric isolation between Al + dissimilar metal
Comparison to alternatives:
| Material | Window frame typical | Density | Cost | |---|---|---|---| | Aluminium (6063) | Extruded sections | 2.7 g/cm³ | ₹200-400/m² frame | | Steel | MS / SS profile | 7.85 g/cm³ | ₹250-500/m² | | uPVC | Extruded sections | 1.4 g/cm³ | ₹400-800/m² (frame + glazing) | | Wood | Solid timber | 0.5-0.9 g/cm³ | ₹500-3000/m² (depends on species) |
Aluminium dominates modern commercial buildings (slim profiles + design freedom + low maintenance); uPVC is competitive for residential energy-efficient windows; wood for premium / heritage applications.
1. Wrong alloy for application. 6063 for extruded window frames; 5xxx for marine; 1100 for non-structural. Match grade to use. 2. Galvanic corrosion at joints with steel. Without isolation, Al corrodes preferentially. Use plastic/rubber gasket between dissimilar metals. 3. No anodising / coating in marine zones. Bare aluminium pits + corrodes in salt air; specify Class A1 anodising or PPG-coated. 4. Cheap supplier without IS / ISI mark. Quality varies; mechanical strength may be below spec. Demand ISI marked. 5. Welded joints in load-bearing aluminium without proper design. Welding reduces strength of heat-treatable alloys (6063, 6061) by 30-50 % at HAZ. Mechanical fastening preferred for high-load. 6. Painting over weathered / oxidised surface without preparation. Paint adhesion poor. Etch or anodise before paint. 7. No allowance for thermal expansion. Al expansion is 2× steel; large facades crack at fixtures. Provide expansion gaps. 8. Wrong finish for environment. Mill finish in coastal location → corrosion. Anodised OR coated. 9. No periodic cleaning. Dirt / atmospheric pollutants accumulate; coating degrades. Annual washing. 10. Casting porosity (for cast components). Voids reduce strength + corrosion resistance. Specify casting quality requirements. 11. Inadequate fastener for aluminium structure. Steel screws / bolts cause galvanic corrosion. Use stainless steel A2-70 or aluminium fasteners. 12. Mixing with reinforced concrete. Cement is alkaline (pH 12+); aluminium corrodes in alkaline environment. Isolate Al from fresh concrete with bitumen / waterproof membrane.
Aluminium application cascade:
1. Design — façade / window / roof / cladding system per architectural intent. 2. Material selection: - Extruded 6063 for window/door frames - Sheet 3003 / 5052 for cladding / roofing - Cast Al-Si for decorative / specific shapes - ACP (aluminium composite panel) for facade modules 3. Surface treatment per environment + finish requirement. 4. Fabrication: - Cutting (mitre / cross) - Joining (mechanical typically; welding only for non-heat-treatable alloys at low temperature) - Glazing fitting (rubber gasket; structural silicone for SSG) 5. Installation: - Fixings (stainless / aluminium fasteners) - Sealing (silicone) - Thermal break gaskets for energy efficiency 6. Quality acceptance: - Visual finish - Plumb / level / square - Operation (window opens smoothly) - Pressure / water-tight tests 7. Maintenance: - Annual washing - Inspection of seals / gaskets - Touch-up coating as needed - Replacement of damaged components
Modern Indian construction trend: - Aluminium dominates commercial (offices, malls, hotels) - Premium residential moving to aluminium framed glass - ACP cladding common on high-rise (modern facade aesthetic) - uPVC competing in energy-efficient residential - Wood for premium / heritage
IS 617 + companion aluminium codes provide the technical baseline. Indian aluminium construction is growing rapidly — Hindalco, Vedanta, Jindal Aluminium are major suppliers; demand for skilled fabricators + installers is high.
| Parameter | IS Value | International | Source |
|---|