Physical Properties of Aluminum: 1050, 3003, 5052 Data for Shops

Most articles on the physical properties of aluminum stop at general statements: light, conductive, corrosion resistant. Those points are covered in our article on six outstanding physical properties of aluminum. This guide takes a different route: it places the physical data of three common sheet alloys, 1050, 3003 and 5052, next to structural steel and explains what each figure is used for in a fabrication shop. Truck body builders, electrical cabinet makers and machine frame fabricators all run these calculations, even if they rarely call them by name.

Key physical figures to remember when choosing aluminum sheet (compiled by H&D Steel)

Physical data by aluminum alloy

The figures below are typical values from the datasheets of European distributors (Aalco, Dinco, BIKAR), cross-checked between at least two sources for each alloy. Where sources differ, a range is given. Structural steel uses the design values of EN 1993-1-1.

Two notes when reading the table. First, these are typical design values, not guaranteed limits: EN 485-2 specifies mechanical properties (proof stress, tensile strength), while physical properties do not appear on the mill certificate of a delivery. Second, thermal and electrical conductivity change with temper, which is why BIKAR gives 3003 a range of 160–200 W/m·K instead of a single value.

Density: weight by alloy

According to Total Materia, aluminum weighs about one third as much as steel. In concrete terms, one square metre of 1 mm sheet weighs 2.68 kg in 5052, 2.71 kg in 1050A and 2.73 kg in 3003, against roughly 7.85 kg for steel. A 5052 sheet of 1,250 × 2,500 mm at 2 mm weighs about 16.8 kg; the same steel sheet weighs almost 49 kg.

The difference between aluminum alloys is only about 2%, but when buying several tonnes by weight it is enough to shift the expected sheet count. Multiply area and thickness by the density of the exact alloy ordered rather than dividing a steel factor by three. Our article on 3mm aluminum sheet weight, tolerance and alloy choice shows a worked example.

Elastic modulus: why aluminum sheet deflects more than steel

This is the most overlooked figure. All three aluminum alloys have an elastic modulus of about 70 GPa, roughly one third of steel (210 GPa). At the same thickness and span, an aluminum sheet deflects about three times as much as steel under the same load.

The key point is that the modulus barely changes between alloys. 5052 is far stronger in tension than 1050, but its stiffness is the same. Changing alloy does not fix deflection; only more thickness, folded edges, embossed ribs or added stiffeners do.

The bending stiffness of a plate is proportional to E times the cube of thickness. To match the stiffness of steel, aluminum needs about 1.44 times the thickness: a 2 mm steel sheet corresponds to roughly 2.9–3 mm of aluminum. Even when thicker, the aluminum sheet still weighs only about half as much. That is why truck body walls and floors converted to aluminum usually go one gauge thicker than the old steel design.

Thermal expansion: leave room when joining aluminum to steel

Aluminum expands at about 23–24 ×10⁻⁶/K, nearly twice the rate of steel (12 ×10⁻⁶/K). A 3 m aluminum panel that sees a 40 °C swing between early morning and midday sun grows by about 2.8 mm; a steel bar of the same length grows by only about 1.4 mm.

That 1.4 mm difference is behind many cases of bulging cladding, torn screw holes and ticking noises on truck bodies and canopies. When fixing long aluminum panels to an outdoor steel frame, drill slotted holes along the length, leave gaps at both ends and do not fully clamp every fastener. In the shop, let freshly machined aluminum parts cool before final dimensional inspection.

Thermal and electrical conductivity: purer alloys conduct better

According to Total Materia, aluminum conducts heat about three times better than steel. Yet the gap between alloys is large: 1050A conducts 210–222 W/m·K, 3003 about 160–200 and 5052 only 138 W/m·K, so 1050A conducts heat roughly 50–60% better than 5052. For electrical conductivity, 5052 reaches only about 57% of 1050A.

Aluminum heat sinks: the purer the alloy, the better the heat conduction — Photo: SHOX ART / Pexels

For electronics fabricators: heat sink plates, power component mounting bases and parts that must carry current should favour 1050, then 3003. Outdoor electrical enclosures, covers and vibration-loaded frames need the strength and corrosion resistance of 5052 more than conductivity. See the alloys available on our aluminum sheet page; for parts stamped in volume from strip, see aluminum coil and slit strip.

High conductivity also affects welding. Heat from the torch spreads quickly through the sheet, while aluminum melts at only about 605–655 °C depending on alloy. Welders moving from steel to aluminum should test settings on scrap of the same alloy and thickness before welding the real part.

Five common mistakes when choosing aluminum by physical properties

1. Switching to 5052 to reduce deflection. 5052 and 1050 have nearly the same modulus; to reduce deflection increase thickness or add ribs and folded edges.
2. Fixing long aluminum panels to a steel frame through tight round holes. Aluminum expands almost twice as much as steel, so in the sun the panel bulges or tears the holes.
3. Choosing 5052 for heat sinks because a stronger alloy seems better. For heat dissipation, 1050 conducts noticeably better.
4. Estimating weight by dividing steel weight by three. This is off by a few percent; use the density of the exact alloy.
5. Treating datasheet physical values as guaranteed for the delivery. The mill certificate confirms chemistry and mechanical properties; physical values are typical design figures.

To learn how aluminum reacts with acids, alkalis and the environment, read our article on the chemical properties of aluminum.

References

• Aalco – Aluminium Alloy 1050A H14 Sheet datasheet
• Dinco – Aluminium Alloy 3003 H14 datasheet
• Aalco – Aluminium Alloy 5052 H32 Sheet and Treadplate datasheet
• Eurocode Applied – Structural steel properties per EN 1993-1-1
• Total Materia – Aluminum properties
• BIKAR – EN AW-1050A and EN AW-3003 data (cross-check of density, expansion, thermal and electrical conductivity)
• Dinco – Aluminium Alloy 5052 datasheet (cross-check of physical data)

If you need 1050, 3003 or 5052 aluminum sheet or coil in the right thickness for truck bodies, electrical cabinets or heat sinks, send your enquiry through our aluminum sheet and coil quotation page or call our hotline/Zalo 0904 678 236 (Sales Department) for advice on the right alloy and thickness for your job.