The classification of aluminium foil

12/24 2025

The classification of aluminium foil looks simple on the surface — thick or thin, shiny or matte — but in reality it follows a precise logic of alloy design, tempering, standards, and application needs. this logic helps buyers choose the right foil the first time and avoid costly mismatches in performance.

Below is a concise, technically accurate overview written from a practical, user-focused perspective, designed for fast reading while still covering the essential parameters and standards.

Looking at aluminium foil through three lenses

Instead of listing dozens of product types, it is more useful to look at aluminium foil through three “lenses” that define its behavior:

• Alloy and temper
• Thickness and mechanical performance
• Surface and processing condition

Almost every foil on the market is a combination of these three dimensions.

Alloy and temper: the DNA of aluminium foil

Alloy is the composition “recipe”. Temper is the way that recipe has been mechanically and thermally treated. Together they determine strength, formability, barrier properties, corrosion resistance and price.

Common alloy families for foil include:

• Pure aluminium series (1xxx)
  Examples: 1050, 1060, 1070, 1100
  Features: very high purity, excellent ductility, best for deep drawing and extreme folding, very good thermal and electrical conductivity, strong resistance to most food environments.
  Typical uses: household foil, flexible packaging base foil, cable wrap, heat barrier foil.

• Manganese aluminium (3xxx, mainly 3003)
  Slightly higher strength than pure aluminium, still good formability, better resistance to some corrosive environments (e.g., slightly acidic or salty conditions).
  Typical uses: container foil, some heat exchanger fins, food trays, semi-rigid packaging.

• Magnesium aluminium (5xxx, limited use in ultra-thin foil)
  Higher strength and better fatigue resistance, but usually used more in sheet and coil than in sub-30 μm foil.
  May appear in thicker foil for industrial insulation or structural applications where strength matters more.

• Iron / silicon containing “foil alloys” (8xxx series, such as 8011, 8079)
  8011: balanced strength and formability, excellent pinhole resistance after rolling, good for household and packaging foil.
  8079: higher elongation, better deep-drawing ability, excellent barrier and flex-crack resistance, commonly used for high‑performance flexible packaging and pharmaceutical foil.

The temper marks what has happened to the alloy after casting. For foil, the most common are:

• O (Annealed, fully soft)
  Maximum ductility and elongation, lower strength. Ideal for deep forming, tight wrapping, blister lidding, embossing and applications that need repeated folding without cracking.

• H18 (Full hard)
  High strength from cold rolling, low elongation. Used where rigidity, flatness and dimensional stability are more important than extreme formability, such as capacitor foil or some industrial laminates.

• H24 / H26 and similar temper codes
  Partially hardened and partially annealed states, tailored to a specific balance between strength and workability. Frequently used in container and tray foil which must be formed but also hold its shape during transport and baking.

In practice, many packaging foils are 8011‑O, 8079‑O, 3003‑H24 or similar, each tuned to a specific converting process such as lamination, coating, printing, or press forming.

Thickness: where “foil” begins and ends

Thickness is not only a dimensional parameter; it also decides barrier performance, mechanical behavior and cost per square meter.

Common thickness ranges can be thought of by function:

• Ultra‑thin foil (about 6–9 μm)
  Used for high‑performance flexible packaging (e.g., aseptic packs, small sachets) and cigarette or confectionery inner liners.
  Offers near-total barrier to light, oxygen and moisture when laminated and well handled, but more sensitive to pinholes from dust or roll defects.

• Standard packaging foil (around 10–20 μm)
  Widely used for food pouches, pharmaceutical blister lidding, yogurt lids, cosmetic sachets and more.
  Good compromise between barrier reliability, mechanical toughness, foldability and cost.

• Container and household foil (about 20–50 μm)
  Container foil for trays, baking containers and semi‑rigid dishes is usually in this range.
  Household foil rolls are often around 9–15 μm for light duty and 15–20 μm for heavy duty, depending on local standards and branding.

• Industrial and insulation foil (up to about 200 μm, sometimes more)
  Used in building insulation, HVAC ducts, cable shielding, and certain technical laminates.
  Thickness here provides rigidity and resistance to tearing rather than just barrier.

As thickness increases, the risk of pinholes during rolling decreases, barrier performance becomes more robust, and stiffness improves—but material cost per area rises.

Surface condition: what you see versus what you need

Aluminium foil is rarely used “bare” in modern industry. Even household foil often involves subtle surface treatments. From a classification viewpoint, several surface dimensions matter:

• Bare foil versus coated foil
  Bare foil: no organic coating; may be lubricated with a very thin rolling oil film that is usually burned off in annealing.
  Coated foil: lacquered, primed or printed with inks, heat‑seal coatings, or functional layers such as epoxy, polyester, or PVC‑free sealants. This is standard in pharmaceutical and food lidding foils.

• One‑side bright, one‑side matte
  Created by “double rolling” two layers together. One side remains bright from contact with polished work rolls; the other becomes matte from foil‑to‑foil contact.
  Packaging designers may choose the side visible to consumers based on aesthetics and ink adhesion behavior.

• Embossed vs. plain
  Embossing adds texture for strength, stiffness, and appearance. Common in household foil, decorative foil, and some insulation products.

Implementation standards: how foil quality is controlled

To ensure that foil made in different mills can be used interchangeably and safely, producers follow widely recognized standards and customer‑specific specs.

dimensions of standardization include:

• Dimensional tolerances
  Tight control of thickness and width variation across the coil. For high‑precision applications (pharma, capacitors), both average thickness and local variations are specified.

• Mechanical properties
  Yield strength, tensile strength and elongation are tested in accordance with standards such as ASTM B479, EN 546 or similar regional norms.
  These values are directly linked to alloy and temper and are critical for forming processes and sealing reliability.

• Surface quality
  Limits on pinholes, rolling lines, stains, color variation and other defects.
  Pharma and food‑grade foils often set strict pinhole density limits per square meter to guarantee barrier integrity.

• Chemical cleanliness and migration
  Particularly for contact with pharmaceuticals, infant food or high‑fat foods, foil and its coatings must comply with regulations such as FDA, EU food‑contact frameworks or national equivalents.
  This includes tests for heavy metals, residual solvents in coatings, and overall migration into food simulants.

Customers often specify compatibility with their converting process: corona treatment levels for lamination, heat‑seal window for lidding foils, and adhesion performance in peelable or weld‑seal designs.

Chemical properties: why aluminium foil is a natural barrier

Although aluminium is a reactive metal, it is protected by a very thin, self‑healing oxide layer (aluminium oxide, Al₂O₃) that forms instantly in air. This layer is to its corrosion resistance and suitability for food, pharma and technical applications.

A typical chemical composition range for a widely used packaging alloy, such as 8011, illustrates how alloying elements tune this behavior:

Notes on this composition:

• Silicon and iron
  Improve strength and rolling performance, and help control grain structure. However, excessive Fe can reduce formability and deepen the gray tone.

• Trace elements (Cu, Mn, Mg, Zn, Ti)
  Kept at low levels to preserve corrosion resistance and avoid unwanted reactions with aggressive contents.
  Titanium, when present, can refine grain size, improving overall mechanical consistency.

For high‑purity foils such as 1060 or 1100, the aluminium content is usually above 99.0–99.6 percent, with very low levels of other elements. This maximizes conductivity and ductility, making these alloys ideal for applications like electrical capacitors and some insulation products.

Matching foil classification to real‑world decisions

From a buyer’s perspective, the classification of aluminium foil becomes practical when it is tied to application questions such as:

• What must this foil withstand: deep drawing, tight folding, heat sealing, retorting, high‑speed unwinding?
• What does it need to block: oxygen, moisture, light, aroma, oils, or electromagnetic noise?
• Will it be in direct contact with food, medicine, insulation adhesives, or corrosive environments?
• Is print appearance and brand presentation critical, or is function more important than aesthetics?

Once these questions are clear, the right combination of alloy (e.g., 8011 vs. 8079 vs. 3003), temper (O vs. H18 vs. H24), thickness range and surface condition (bare vs. coated, bright vs. matte, embossed vs. plain) can be selected with confidence.

classification from this integrated perspective helps customers move beyond generic labels like “household foil” or “pharma foil” and instead specify a technically correct product that runs smoothly in production, protects contents reliably, meets regulatory demands, and optimizes total cost over the full lifecycle of use.

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