6061 aluminum plate mainly contains alloy metals of 1% magnesium and 0.6% silicon, and 7005 plate 4.5% zinc and 1.4% magnesium. T6 is a heat treatment method, suitable for solution heat treatment without cold working (straightening and leveling can be carried out, but does not affect the mechanical performance limit) of the product. T6 is the nominal value of the 20-hour tempering t treatment, and there is also a 10-hour tempering t4 heat treatment.
The tensile strength of 6061 t6 aluminium is 45000 PSI, and that of 7005 51000 PSI. The intensity of knuckle down for 6061 t6 is 40000 PSI, and 7005 42000 PSI. In this regard, we can see that 7005 has a better strength than 6061. Nevertheless, The idea that “the larger the number of an alloy name, the better the properties” is misleading. Although some aluminium alloys are more expensive, they do not surpass others in some properties like hardness, lightness, service life etc. For example, 3xxx proves to be heavier than 1xxx aluminium, and 7xxx has much poorer corrosion resistance than 5xxx.
The mechanical properties of 6061 aluminium sheet are medium strength, good plasticity and excellent corrosion resistance. 7005, on the other hand, cannot be welded, and its corrosion resistance is quite poor. It is mostly used for CNC cutting. Zinc is the main alloying element in 7005. With a little magnesium alloy, the material can be heat treated to achieve very high strength. 7005 aluminum plate is lighter and stronger, but 6061 aluminium sheet is more plastic and corrosion resistant. And the price of the former is higher.