8079 vs 8011 vs 8021 Álpappír: Hvernig á að velja
These three alloys account for the overwhelming majority of 8xxx-series aluminum foil in global trade, and buyers ask about them constantly — usually at the point of writing a specification and not being certain which one it should name.
The short answer: 8011 is the general-purpose workhorse, 8021 og 8079 are the high-purity specialists. The differences look small on a chemical composition table and are significant on a production line.
Quick answer
| If you need… | Veldu | Hvers vegna |
| Flöskuhettur, ROPP húfur, PTP pharmaceutical lidding | 8011 | Strength plus formability, best cost position |
| Heimilispappír, ílátspappír, HVAC fin stock | 8011 | Proven, economical, víða í boði |
| Cold-form alu-alu pharmaceutical blister | 8021 eða 8079 | Needs deep-draw ductility in O temper |
| High-barrier food packaging (kaffi, Kjöt, sjávarfang, gæludýrafóður) | 8079 | Excellent barrier consistency, very low pinhole count |
| Flexible packaging laminates, tvöfalt núll álpappír | 8079 | Handles ultra-thin gauge with good integrity |
| Pouch / laminate battery packaging film | 8021 | Formability and barrier in thin gauges |
| Cost is the dominant constraint | 8011 | Lowest cost of the three |
If you only remember one thing: 8011 carries more alloying elements and is stronger and cheaper; 8021 og 8079 are purer, more ductile, and better at deep drawing and barrier. Neither is “betri” — they are different tools.
Efnasamsetning
The whole story is in the impurity limits. All three are Al-Fe-Si alloys, but the allowable levels of silicon, kopar, mangan, and other elements differ sharply.
| Frumefni | 8011 | 8021 | 8079 |
| Og | 0.50 – 0.90% | ≤ 0.15% | 0.05 – 0.30% |
| Fe | 0.60 – 1.00% | 0.70 – 1.30% | 0.70 – 1.30% |
| Cu | ≤ 0.10% | ≤ 0.05% | ≤ 0.05% |
| Mn | ≤ 0.20% | ≤ 0.05% | ≤ 0.05% |
| Mg | ≤ 0.05% | ≤ 0.05% | ≤ 0.05% |
| Zn | ≤ 0.10% | ≤ 0.05% | ≤ 0.10% |
| Af | ≤ 0.08% | — | — |
| Al | Afgangur | Afgangur | Afgangur |
What this means practically:
8011 permits substantially more silicon and manganese. Those elements raise strength, which is why 8011 is the choice where stiffness matters — bottle caps, PTP lidding that has to rupture cleanly, container foil that has to hold a shape.
8021 og 8079 restrict Si, Cu and Mn to trace levels. Lower alloying content means:
- Higher ductility and elongation — critical for cold forming and deep drawing
- Fewer and smaller intermetallic particles — which is where pinholes initiate
- Betri tæringarþol and more uniform barrier performance
- More consistent deep-draw behaviour — fewer cracks at high draw ratios
The trade is strength and cost. Purer means softer and more expensive.
Vélrænir eiginleikar
O skap (annealed / mjúkur)
| Álblöndu | Typical tensile strength | Typical elongation |
| 8011-O | 85 – 120 MPa | ≥ 20% |
| 8021-O | 80 – 110 MPa | ≥ 22% |
| 8079-O | 80 – 110 MPa | ≥ 22% |
H18 skap (full hart)
| Álblöndu | Typical tensile strength | Typical elongation |
| 8011-H18 | ≥ 160 MPa | ≥ 1% |
Note the elongation gap in O temper: 8021 og 8079 stretch further before failing. That margin is exactly what cold-form blister forming consumes.
Formability and barrier performance
Djúp teikning / kalt myndast
This is the clearest separation between the alloys. In cold-form alu-alu blister production, the foil is mechanically drawn into a cavity — often to significant depth — without heat. The material that survives that process needs high elongation and low intermetallic content.
8021-O and 8079-O are the standard selections. 8011-O is generally not used for deep-draw cold forming.
If you have experienced cracking, pinholing or uneven wall thickness at the corners of cold-formed cavities, alloy selection is the first thing to check.
Pinhole performance
Pinholes initiate at intermetallic particles and at inclusions. Lower alloying content means fewer nucleation sites.
For ultra-thin gauges — double-zero foil below 0.01 mm — this becomes decisive. 8079 is the conventional choice for very thin foil precisely because it holds integrity at gauge where a more heavily alloyed material would show pinholes.
Hindrun
At pharmaceutical and high-barrier food gauges, all three provide effectively complete barrier against moisture, oxygen and light through the aluminum layer itself. The differentiator is not the intrinsic barrier of the metal — it is samræmi, which comes down to pinhole control and gauge uniformity. This is where 8079’s reputation comes from.
Typical application map
| Umsókn | Primary alloy | Skapgerð | Typical gauge |
| PTP pharmaceutical lidding | 8011 | H18 | 0.020 – 0.030 mm |
| Cold-form alu-alu blister | 8021 / 8079 | O | 0.045 – 0.065 mm |
| Flöskuhettur, ROPP húfur | 8011 | H14 / H16 | 0.16 – 0.30 mm |
| Heimilispappír | 8011 | O | 0.010 – 0.020 mm |
| Gámur / tray foil | 8011 / 3003 | H22 / H24 / O | 0.030 – 0.150 mm |
| Kaffi, Kjöt, sjávarfang, umbúðir fyrir gæludýrafóður | 8079 | O | 0.006 – 0.015 mm |
| Flexible packaging laminate | 8079 / 1235 | O | 0.006 – 0.009 mm |
| Double-zero foil | 8079 / 1235 | O | < 0.01 mm |
| HVAC / heat exchanger fin stock | 8011 / 1100 | H22 / H24 | 0.08 – 0.20 mm |
| Cable shielding foil | 8011 / 1235 | O | 0.012 – 0.20 mm |
| Cigarette / tóbakspappír | 8079 / 1235 | O | ~0,007 mm |
| Battery pouch / laminate film | 8021 / 8079 | O | 0.025 – 0.040 mm |
Choosing for pharmaceutical packaging
The most common confusion in this category:
| Krafa | Correct choice | Hvers vegna |
| Press-through lidding (PTP) | 8011-H18 | Hard temper gives clean rupture; the cavity is formed by a plastic film, so the foil does not need deep-draw ductility |
| Cold-form alu-alu | 8021-O or 8079-O | The foil itself is drawn into the cavity; needs the elongation |
| Tropical / child-resistant blister | Specified per structure | Usually combines both |
Do not use 8011-O for cold forming, and do not use 8021-O for PTP lidding. Both will fail — the first by cracking during forming, the second by stretching instead of rupturing on press-through.
Within cold-form, 8021 og 8079 are close substitutes. Selection often comes down to which gauge and which supplier’s material has already been validated on your specific blister machine. If you have a validated material, changing alloys requires revalidation — factor that cost into any switch.
Choosing for food and flexible packaging
- 8079 is the stronger choice for high-barrier flexible packaging — coffee, Kjöt, sjávarfang, retort pokar, gæludýrafóður, and any application where a thin gauge must hold barrier integrity through lamination and distribution.
- 8011 is appropriate for household foil, container foil and semi-rigid containers where gauge is thicker and barrier demands are less extreme.
- 1235 is worth considering for very thin flexible laminates where cost matters and the gauge is above roughly 0.006 mm — it is often used alongside or instead of 8079 depending on mill capability.
If your pack is failing moisture-vapour transmission testing, moving from 8011 til 8079 at the same gauge is one of the first things to evaluate.
Kostnaður
Indicative relative positioning:
| Álblöndu | Relative cost | Ástæða |
| 8011 | Lægsta | Higher alloying tolerance, largest production volume, most competitive supply |
| 8079 | Hærra | Tighter composition control, higher purity requirement |
| 8021 | Hærra | Tighter composition control, particularly on Si |
The premium for 8021 og 8079 yfir 8011 is real but is usually small relative to the total converted pack cost. If a purer alloy eliminates a forming failure, a pinhole rejection or a stability failure, it pays for itself immediately. The right comparison is not foil price against foil price — it is foil price against total cost of rejected packs.
Decision tree
When they can be substituted
Be careful here. On a specification sheet these alloys can look interchangeable; on a validated production line they often are not.
Lower-risk substitutions:
- 8021 ↔ 8079 in cold-form pharmaceutical applications — close in composition and behaviour, but still requires validation on your equipment
- 8011 ↔ 1235 in some general flexible packaging laminates at thicker gauges
Higher-risk substitutions:
- 8011 → 8079 for PTP lidding: changes press-through force and seal behaviour
- Any alloy change in a validated pharmaceutical pack: triggers revalidation
- Any change at gauges below 0.01 mm: pinhole behaviour changes materially
Always run trial material on your own equipment before switching a validated specification. The mill can tell you the alloy meets the standard; it cannot tell you how it will behave on your line.
Frequently asked questions
Er 8079 betri en 8011? Not in absolute terms. 8079 is purer, more ductile and better at barrier and thin gauges. 8011 er sterkari, cheaper and better for applications needing stiffness and clean rupture. The right alloy depends on the job.
Can I use 8011 instead of 8079 for pharmaceutical packaging? For cold-form alu-alu, no — you need 8021-O or 8079-O. For high-barrier thin-gauge laminates, 8079 is preferable.
Hver er aðalmunurinn á milli 8021 og 8079? They are close in composition and application. 8021 has a tighter silicon limit (≤0,15%) á meðan 8079 allows slightly more (0.05–0,30%). In practice both are used for cold-form pharmaceutical foil, and selection often comes down to gauge availability and which material is validated on your equipment.
Hvers vegna er 8011 most common for bottle caps? Bottle cap and ROPP cap stock needs strength to hold thread form and to survive the capping process, plus enough formability to be rolled and knurled. 8011 in H14 or H16 hits that balance at the lowest cost.
Which alloy should I use for household aluminum foil? 8011-O. It is the industry standard for household foil and container foil, and there is no performance reason to pay for a purer alloy.
Does a purer alloy always mean better barrier? The intrinsic barrier of solid aluminum is effectively absolute at these gauges. What purer alloys improve is samræmi — fewer pinholes and more uniform gauge, which means fewer packs that fail. The benefit shows up in rejection rates, not in the theoretical barrier number.
Which is cheaper, 8021 eða 8079? They are broadly comparable, both carrying a premium over 8011. Actual pricing depends on gauge, volume and market conditions — request a quote with your specification.
Can I switch alloys to save money on an existing pack? Sometimes, but on validated pharmaceutical packaging the cost of revalidation frequently exceeds the material saving. Model the total cost — including validation, trial runs and risk — before switching.
Not sure which alloy your application needs?
Send us your application, mál, forming process and the specification you are currently using. If there is a better-value alloy for the job we will tell you; if your current specification is already right, we will tell you that too.