Aluminum Cans vs. Cast Aluminum Scrap: Which Melts Better?
Quick answer
Clean cast aluminum scrap is often more predictable than beverage cans because it usually has more metal per piece and less coating surface area. Aluminum cans can melt, but they are thin, coated, easy to oxidize, and can produce more dross relative to usable metal. Identify, clean, dry, and log the charge.
Compare the charge types
| Charge type | Advantage | Limitation |
|---|---|---|
| Aluminum cans | Easy to collect and compact | Coatings, thin metal, high surface area, lower yield |
| Cast aluminum scrap | Often denser and easier to charge | Alloy identity may be uncertain |
| Machined offcuts | Traceable if source is known | Oil and chips must be controlled |
| Unknown mixed scrap | None until identified | Contamination and fume risk |
What real users ask
Users often ask why a full bucket of cans makes a small ingot. The answer is usually density, coating, oxidation, dross, and freeboard, not a furnace capacity failure by itself.
Safety and setup
Reject wet, sealed, oily, painted, magnesium-rich, or unknown items until they are identified and prepared. Moisture and coatings change both safety and yield.
Frequently asked questions
Do cans damage the furnace?
The bigger risk is process contamination, oxide/dross, and poor yield. Follow the crucible and furnace instructions.
Should I compact cans first?
Only if compacting does not trap moisture or unknown contamination.
Is cast aluminum always better?
No. It is better only when the alloy and condition are known enough for the intended casting.
Bottom line
For practical aluminum recycling, clean identified scrap usually beats random cans. If cans are used, treat them as a high-surface-area, coated charge with yield and dross penalties.