Aluminum Alloy Reference
One page per alloy: what it is made of, what the temper means, how it machines, and what it does not do. For side-by-side decisions, the guides and the alloy selector go deeper. For how the part is made, see machining and casting processes.
6000 series, aluminum-magnesium-silicon
The default machining alloy. Cuts fast, welds, anodizes evenly, and every shop stocks it in plate, bar and block.
6000 series, aluminum-magnesium-silicon-manganese
The alloy a European or UK shop stocks where a US drawing calls for 6061. Close enough to substitute on most machined parts.
6000 series, aluminum-magnesium-silicon, lower alloy content than 6061
The extrusion alloy, not the machine-from-solid alloy. Built to flow through a die, and it shows up on a CNC quote as end-machining on an already-extruded profile.
7000 series, aluminum-zinc-magnesium-copper
Close to double the yield strength of 6061 for the same weight. The alloy to reach for when a part is bending or yielding, not when it needs to be cheap.
2000 series, aluminum-copper-magnesium
Specified for fatigue life on parts that flex over thousands of cycles, not for static strength alone. Corrodes badly if left bare.
5000 series, aluminum-magnesium, not heat treatable
A formed-sheet alloy that also gets machined for enclosures and brackets. Excellent corrosion resistance, gummy to mill.
5000 series, aluminum-magnesium, the highest-magnesium common wrought alloy, not heat treatable
Marine and structural plate. Holds up in salt water and welds cleanly, but it will never reach 6061 hardness because it cannot be heat treated.
Cast aluminum plate, stress relieved after casting, not a wrought alloy
Cast, not rolled, then stress relieved specifically so it stays flat after material comes off one side. The plate to reach for when flatness matters more than strength.
Questions
Which alloy should I pick if I do not know yet?
6061-T6. It is right for most brackets, housings, mounts and plates: it cuts fast, welds, anodizes evenly and every shop stocks it. Move off it only when something specific forces the choice.
Why are there separate pages for alloys the blog already compares?
The blog guides compare two alloys against each other for a specific decision. These pages are the reference profile for one alloy on its own, composition, properties, machining and finishing behaviour, so you have one page to send a colleague or a shop instead of a comparison written for someone else's question.
Are the property scores measured values?
No. Yield figures are typical published values for the stated temper. The one to five scores for weld, anodize, corrosion, strength, flatness and machinability are editorial judgements for comparing these specific alloys against each other, not lab measurements.