Aluminum is one of the most widely used non-ferrous metals in the world due to its attractive properties like light weight, corrosion resistance and easy machinability. Three common wrought aluminum alloys frequently employed in construction and manufacturing applications are 5052, 6061 and 6063 aluminum. These alloys each offer unique mechanical properties that make them well-suited for different types of components and structural elements. Today, we’re going to find out the differences between Aluminum 5052, 6061 and 6063.
What is Aluminum 5052?
5052 aluminum is a non-heat-treatable aluminum alloy that provides good corrosion resistance and mechanical properties. 5052 aluminum contains 2.5-3.5% magnesium as its major alloying element. It may also contain small amounts of chromium. 5052 aluminum has higher strength than pure aluminum but is not as strong as heat-treatable alloys like 6061 or 7075. It has excellent corrosion resistance, especially in marine environments.
Applications: Common applications include storage tanks, pipe, architectural panels and food and chemical containers where corrosion resistance is important. It’s also used for some vehicle and aircraft components.
Machinability: 5052 has good machinability and can be readily welded using common processes like MIG, TIG and resistance spot welding.
Heat Treatment: Unlike alloys like 6061, 5052 is not artificially aged or heat treated to increase strength. It relies on work hardening and solution treatment for strength.
Standards: Meets ASTM B209 specifications for aluminum alloy plates, sheets and circles in 5052 composition. Commonly available in tempers like O (annealed) and H111.
What is Aluminum 6061?
061 aluminum is a precipitation-hardened aluminum alloy that provides very good mechanical properties coupled with excellent corrosion resistance. 6061 contains about 0.8-1.2% magnesium and 0.4-0.8% silicon as its major alloying elements. It may also contain chromium and copper. 061 has higher strength than non-heat-treatable alloys like 5052. When T6 tempered, its ultimate tensile strength can exceed 62,000 psi. It also has good fatigue strength and machinability.
Applications: Commonly used in aircraft structures, bicycle frames, transportation and industrial applications. Also commonly used for structural and load-bearing parts that require good strength.
Heat Treatment: When solution heat treated and artificially aged (temper T6), the magnesium forms fine precipitates that increase strength. This heat treatment is essential to obtain 6061’s rated properties.
Forms: Available as extrusions, forgings, plate, sheet, bar stock and tubing. Standards include ASTM B210 for sheet/plate and ASTM B221 for extrusions.
What is Aluminum 6063?
6063 aluminum is another aluminum alloy that is frequently used. Similar to 6061, 6063 contains magnesium (0.6-1.2%) as its primary alloying element. It also contains silicon (0.4-0.8%). 6063 has slightly lower strength ratings than 6061. But it provides very good corrosion resistance as well as workability and weldability.
Heat Treatment: Like 6061, 6063 can be artificially aged (T6 temper) after solution heat treatment to produce fine precipitates that increase its tensile strength.
Applications: Common uses include architectural extrusions for window frames and doors. Also used for transportation, marine, bicycle and outdoor furniture extrusions.
Forms: Typically produced as extrusions rather than other wrought products. Standard tempers are O (annealed), T4 (solution heat treated), T5xx (strain hardened), T6 (artificially aged).
Advantages: Has excellent corrosion resistance even without anodic coatings. Very good strength-to-weight ratio compared to steel. Easy to machine and form.
Aluminum 5052 vs 6061 vs 6063
Strength – 6061 has the highest strength, followed by 6063. 5052 has the lowest strength of the three since it cannot be precipitation hardened through heat treatment like 6061 and 6063.
Corrosion Resistance – All three alloys provide excellent corrosion resistance, even without anodizing or other surface treatments. They resist corrosion well in marine and other harsh environments.
Machinability – 6061 is easiest to machine, followed by 6063. 5052 requires slightly more tool force to machine but still cuts smoothly.
Heat Treatment – 6061 and 6063 can both be artificially aged (T6 temper) to significantly boost strength. 5052 is a non-heat-treatable alloy whose properties cannot be enhanced through aging.
Applications – 6061 is most common in structural applications. 5052 is used for tanks, piping, siding. 6063 is used for architectural extrusions, transportation and marine uses.
Forming – 6061 is available in cast/wrought products. 5052 and 6063 are more commonly formed by rolling or extrusion as they work harden significantly.
Cost – 5052 is the least expensive. 6061 often costs 10-15% more than 5052. 6063 typically costs 5-10% more than 5052.
Differences In Weldability & Thermal Conductivity Between 5052, 6061 And 6063
Weldability:
5052 – Excellent weldability. Welds done with MIG, TIG or resistance welding.
6061 – Very good weldability. Tends to be slightly more brittle after welding than 5052.
6063 – Very good weldability, similar to 6061. Can also be brazed.
Thermal Conductivity:
5052 – Thermal conductivity of 116-162 W/mK. Lower magnesium content gives it the lowest thermal conductivity.
6061 – Thermal conductivity of 167 W/mK. Higher magnesium leads to better thermal transfer.
6063 – Thermal conductivity of 167 W/mK. Similar to 6061 due to matching alloy composition.