Aluminium Grade-by-Grade Identification Guide

Aluminium sorts primarily by alloy family, then by form. See aluminium alloy grades guide for the full series breakdown.

• Extrusion 6063 / 6061: matte grey hollow profiles (window frames, curtain walls). Top rate. Strip rubber gaskets and thermal-break strips before weighing.
• Sheet & clip (3000/5000): 0.5–3 mm cladding, roofing, ducting. Pays slightly below extrusion. PVDF-painted sheet takes a small discount.
• Cast aluminium: dull grey engine blocks, gearbox cases, cookware. 7–12% silicon content. Must be iron-free — steel inserts drop it to mixed.
• Turnings / swarf: CNC chips. Drain oil and moisture to avoid the wet-turnings deduction.
• UBC (beverage cans): 3104/5182 body-and-lid mix. Compact before delivery.
• Mixed / irony: anything with steel or stainless attached. Last-resort bin — pull iron with a magnet first.

Preparation Tips to Maximise Aluminium Payout

• Sort by alloy family. Three bins (6000 extrusion, 3000/5000 sheet, cast), three rates.
• Remove iron and stainless. A fridge magnet on a string sorts 95% of contaminants in minutes.
• Drain oil from cast and turnings. Tip and drain overnight; wet turnings lose 5–10% on moisture.
• Strip rubber gaskets and thermal-breaks from extrusion with a box-cutter.
• Keep painted and unpainted sheet separate — paint costs 3–5% in dross allowance.
• Compact UBC cans into bags or small bales for faster weighing.

Where Aluminium Scrap Comes From in Singapore

• Window and curtain-wall replacement: 6063 extrusion from HDB retrofits, commercial re-glazing, condo facade upgrades.
• Facade / cladding refit: ACP skins, rainscreen, louvre systems from building re-cladding.
• Vehicle dismantling: cast engine blocks, gearbox cases, wheel rims from workshops and ELV yards.
• Machining shops: 6061/7075 turnings and block offcuts from Woodlands, Ang Mo Kio, Jurong.
• Beverage industry: UBC from F&B outlets and aggregators.
• Electrical distribution: aluminium overhead conductor and bus-bar from utility upgrades.

For commercial supply and stock, see aluminium supplier page.

What Happens After We Buy Your Aluminium

Aluminium bins through an eddy-current separator to catch stray copper, brass, and steel. Clean extrusion is baled, cast is sheared to furnace charge size, turnings are de-oiled in a centrifuge. Shipments go to secondary smelters in Malaysia, Thailand, and Indonesia, where material is re-melted (reverberatory for wrought, rotary for cast), de-gassed, chemistry-corrected, and cast into billets that feed extrusion presses.

Secondary aluminium uses ~5% of the energy of virgin smelting from bauxite — one of the biggest CO₂ savings of any recycled material. Aluminium recycles indefinitely. See live rates at scrap metal prices Singapore.

More Frequently Asked Aluminium Questions

What is the difference between 6063 and 6061?

6063 is the architectural extrusion alloy — softer, used for window frames and curtain walls. 6061 is stronger (higher Mg and Si), used for marine fittings, bike frames, machined parts. For scrap grading we treat both as “6000 series extrusion” at the same rate.

Do you buy painted aluminium at the same rate?

Painted extrusion and sheet take a 3–5% discount vs unpainted because paint creates extra dross at the smelter. If you have both streams, separating them is worth the effort.

What about aluminium cans versus extrusion?

UBC is a mixed 3104/5182 alloy with paint and lacquer, so it sits 15–25% below clean 6063 extrusion. Compact cans tight before delivery — loose cans add volume without weight.

How do I tell aluminium from stainless?

Weight: aluminium is about one-third of stainless at the same volume. Magnet: stainless 304 can be weakly magnetic when cold-worked, aluminium is fully non-magnetic. Spark test on a grinder: aluminium does not spark, stainless throws short white sparks.

Do you buy turnings with coolant still on them?

Yes, with a 5–10% moisture deduction. Drain-and-bag for 24 hours and the deduction drops to near zero. We can supply drainable IBC totes for ongoing machining-shop volumes.

Is cast aluminium worth less than extrusion?

Yes, 10–20% less. Cast alloys (A356, ADC12) contain 7–12% silicon plus copper and zinc, reducing re-melt yield for wrought applications. Keep cast separate and remove any steel inserts.