Round flat
The standard slug for backward-extruded cans, tubes and housings.
Impact extrusion slugs
1050 Aluminium Slugs: Punched or Sawn
1050 aluminium slugs are discs or blanks of 99.5 % pure aluminium, soft-annealed so they flow readily under the punch in impact extrusion. They are the economical everyday choice for collapsible tubes, aerosol and bottle bodies, capacitor cans and small housings. Metline supplies 1050 and 1050A slugs, punched from strip or sawn from rod, to your size, shape and surface specification, worldwide.
- Purity
- ≥ 99.5 % Al
- Temper
- O (annealed)
- Shapes
- Round, perforated, domed, oval
- Standard
- EN 570 · EN 573-3
Why 1050 is used for slugs
Impact extrusion turns a slug into a hollow part in one stroke: the punch strikes the slug in a die and the metal flows up around it (backward extrusion), out through an opening (forward extrusion), or both. Only very ductile, low-strength metal can make that flow without cracking, which is why commercially pure aluminium dominates.
1050 contains at least 99.5 % aluminium, with iron and silicon as the main impurities. Annealed, it combines low flow stress, high elongation and a low work-hardening rate, so it extrudes thin, tall walls with modest press force. It costs less than higher-purity 1070 and is a little stronger, which helps where the part must resist denting.
EN AW-1050A, the European variant, has nearly identical limits and is the usual European designation for these slugs. 1050 also has good corrosion resistance, high thermal and electrical conductivity, and takes lacquering, printing and anodising well.
1050 / 1050A chemical composition (wt %)
| Element | 1050 (AA) | EN AW-1050A |
|---|---|---|
| Silicon (Si) | 0.25 max | 0.25 max |
| Iron (Fe) | 0.40 max | 0.40 max |
| Copper (Cu) | 0.05 max | 0.05 max |
| Manganese (Mn) | 0.05 max | 0.05 max |
| Magnesium (Mg) | 0.05 max | 0.05 max |
| Zinc (Zn) | 0.05 max | 0.07 max |
| Titanium (Ti) | 0.03 max | 0.05 max |
| Vanadium (V) | 0.05 max | — |
| Others, each | 0.03 max | 0.03 max |
| Aluminium (Al) | 99.50 min | 99.50 min |
Limits per Aluminum Association registration and EN 573-3. The actual analysis of each lot is reported on the mill certificate.
Mechanical and physical properties
| Temper | Tensile strength | Yield strength | Elongation | Hardness |
|---|---|---|---|---|
| O, typical | About 76 MPa | About 28 MPa | About 35 – 40 % | About 20 HB |
| O, EN 485-2 range (1050A sheet) | 65 – 95 MPa | ≥ 20 MPa | — | — |
| H14, typical (for reference) | About 110 MPa | About 105 MPa | About 10 % | About 30 HB |
Physical properties
- Density
- 2.705 g/cm³
- Melting range
- About 646 – 657 °C
- Thermal conductivity
- About 229 W/m·K
- Electrical conductivity
- About 61 – 62 % IACS
- Modulus of elasticity
- About 69 GPa
Slugs are normally delivered fully annealed. Hardness is the property most press shops control on receipt: consistent, low hardness gives consistent wall thickness and tool life. Tell us your hardness window and we will certify against it.
Sizes, shapes and slug weights
Typical supply range
- Diameter
- About 10 – 200 mm, depending on route
- Thickness
- About 2 – 25 mm
- Shapes
- Round, perforated, domed or concave, oval, square and rectangular
- Temper
- O (annealed); other conditions on request
- Surface
- Tumbled, shot-blasted or sand-blasted; lubricant-ready
- Tolerances
- To EN 570 or to your drawing
Perforated (centre hole)
For open-ended collapsible tubes, nozzles and parts with a through bore.
Domed, concave or conical
Pre-shaped faces that improve metal flow and reduce the force needed for deep parts.
Oval, square and rectangular
For non-round cans, prismatic battery cases and rectangular housings.
| Diameter (mm) | Thickness (mm) | Mass per slug (g) | Slugs per 25 kg |
|---|---|---|---|
| 20 | 3 | 2.5 | 9806 |
| 25 | 4 | 5.3 | 4706 |
| 27 | 5 | 7.7 | 3228 |
| 35 | 5 | 13.0 | 1921 |
| 40 | 6 | 20.4 | 1225 |
| 45 | 6 | 25.8 | 968 |
| 50 | 7 | 37.2 | 672 |
| 54 | 8 | 49.6 | 504 |
| 63.5 | 8 | 68.5 | 364 |
| 74 | 10 | 116.3 | 214 |
| 90 | 12 | 206.5 | 121 |
| 116 | 15 | 428.8 | 58 |
Mass = π/4 × d² × t × density, for a solid round slug with no centre hole. Perforated, domed or grooved slugs weigh less; the exact slug mass is set from the volume of your finished part plus trim allowance.
How 1050 slugs are made and finished
| Route | How it works | Best for |
|---|---|---|
| Punched from strip | Cast or rolled strip is cold rolled to thickness, slugs are blanked on high-speed presses, then annealed and finished | Thin to medium slugs in high volume: aerosol, tube and capacitor slugs |
| Sawn from rod or bar | Cast or extruded rod is sawn to length, then annealed and finished | Thick slugs, large diameters and short runs; low scrap |
After cutting, slugs are annealed to a uniform soft condition, then tumbled or blasted. The roughened surface removes burrs and oxide and holds the press lubricant (commonly zinc stearate) evenly, which reduces friction and galling in the die. Dimensions, mass and hardness are sampled throughout production.
Applications of 1050 slugs
- Collapsible tubes: toothpaste, pharmaceutical ointments, cosmetics, adhesives and food pastes
- Aerosol and bottle bodies: personal care, household and technical sprays
- Electrical: electrolytic capacitor cans and small battery cases
- Industrial: cartridge and filter housings, shielding cans, small cylinders and caps
Choose 1070 for the deepest draws and thinnest walls, and 3003 when the finished part needs more strength.
How to order 1050 slugs
- SpecifyGrade (1050 or 1050A), diameter or outline, thickness, centre hole, temper, surface treatment, tolerance and quantity; a drawing of the slug or the finished part helps.
- ConfirmWe confirm the production route (punched or sawn), tolerance basis (EN 570 or your drawing), test documents and EXW, FOB, CIF or DAP terms.
- SampleTrial quantities can be supplied so you can run them on your press before a production order.
- Produce and inspectSlugs are cut, annealed, surface treated, then checked for dimensions, mass, hardness and surface.
- Pack and shipMoisture-protected cartons or bags on export pallets, with an EN 10204 3.1 certificate.
References and standards
- EN 570 – Aluminium and aluminium alloys: impact extrusion slugs obtained from wrought products, specification
- EN 573-3 – Chemical composition and form of wrought products
- The Aluminum Association – International Alloy Designations and Chemical Composition Limits
- ASM Handbook, Vol. 14A – Metalworking: Bulk Forming (impact extrusion)
1050 aluminium (aluminum) slugs: FAQs
What is the difference between 1050 and 1050A slugs?
Both contain at least 99.5 % aluminium. 1050A is the European (EN 573-3) designation with slightly different limits on zinc and titanium; for impact extrusion they behave the same.
Why are 1050 slugs annealed?
Annealing makes the metal soft and uniform so it flows into thin walls without cracking, keeps press loads down and gives consistent wall thickness from slug to slug.
Should I choose 1050 or 1070 slugs?
1070 (99.7 % Al) is softer and more ductile, suited to the thinnest walls and deepest parts. 1050 is slightly stronger and lower in cost, and suits most tubes, cans and housings.
Are slugs supplied with lubricant?
Slugs are normally supplied tumbled or blasted and clean, ready for your lubrication step. Pre-lubricated slugs can be discussed on request.
How is slug size chosen?
From the volume of the finished part plus the trim allowance: slug mass = part mass + trim. Diameter matches the die cavity less a small clearance.
Need 1050 aluminium slugs?
Send the slug size, shape, surface and quantity, and we will reply with certification and a delivered price.
