Metal
Aluminum 6061
The default machining alloy. Strong enough, light, and it cuts fast.
Published values for unfilled grades at 23 °C unless stated. Confirm against the supplier datasheet for the grade you specify.
What it is
6061 is a magnesium-silicon alloy and the most widely machined aluminum in the world. In the T6 temper it has roughly the yield strength of mild steel at a third of the weight, and it cuts at high spindle speeds without work hardening.
It anodises cleanly to a uniform finish, welds well, and is available everywhere in plate, bar, and extrusion. When a drawing says "aluminum" and nothing else, this is what it gets made from.
Where it is used
- Machined housings, brackets, and mounting plates
- Structural frames and extruded profiles
- Heat sinks and thermal management components
- Jigs, fixtures, and tooling plates
- Prototype parts intended for die casting later
Processing notes
Machines at high speed with sharp uncoated or polished carbide. Chip evacuation, not cutting force, is the limiting factor.
Welds readily by TIG or MIG, but the heat-affected zone loses temper. Post-weld heat treatment restores it if the joint is structural.
Stress relieves after heavy roughing. On thin plate parts, rough, rest, then finish or the part will bow.
Available through
Design notes
Internal corner radii should be at least a third of the pocket depth. Sharper corners force a small tool and a long cycle.
Minimum practical wall on a machined part is about 0.8 mm; below that the part deflects under the cutter.
Standard machining tolerance is ±0.125 mm. Tighter is achievable but should be called out only where it is needed.
Grades and variants
- 6061-T6, the standard machining temper
- 6061-T651, stress relieved plate, better for flat parts
- 6082, the common European equivalent
- 6063, better extrusion surface, lower strength
- 5052, for sheet metal forming rather than machining
Specifying this material?
Send your CAD and target volumes. We come back with a price, a lead time, and any material or design notes that would reduce either.