Ni tarakimu ya tatu na ya nne, kuonyesha maudhui ya alumini.
2-8 ni tarakimu ya tatu na ya nne, ambayo haina maana maalum na hutumiwa tu kutofautisha aloi nyingine.
Alumini imegawanywa katika alumini safi, alumini ngumu, alumini ngumu sana, alumini ya kuzuia kutu na alumini ya kughushi.
Kwa mfano
- 1 series pure aluminum has the most aluminum content, reaching more than 90%
- 2-Series hard aluminum alloy, containing copper and Cu, with high hardness
- 3-Series antirust aluminum alloy, containing manganese and Mn, na upinzani mzuri wa kutu
- 5-series antirust aloi ya alumini, manganese Mn, magnesium mg, low density and high tensile strength
- 6-series forged aluminium alloy, magnesium mg, silicon Si, malleable (kupinda)
- 7-series superhard aluminum alloy, zinc containing Zn, Mg, Cu, shaba, high hardness and high strength