6061 and 6063 belong to 6 department they are aluminum magnesium (+) silicon aluminum alloy and 7075 mainly based on aluminum zinc alloy element. The first in the basic ingredients to both behind and are quite different.
As for the difference between 6061 and 6063 is small the silicon content of the former between 0.4 to 0.8, magnesium content between 0.8 to 1.2; 0.2 0.6, and 6063 silicon content in magnesium content in 0.45-0.9 because of silicon and magnesium content, general said 6061 than 6063 in hardness. 6061 and 6063 on the tensile strength also has the very big difference, along with the annealing hardening is different under the same conditions the former both tensile strength between less than or equal to 150-290, the latter is less than or equal to between 135-240.
Finally USES the three also have very big difference:
1.6061 aluminum alloy board request has the certain strength, weldability and high resistance to corrosion of all kinds of industrial structural, such as manufacturing truck, tower building, vessel, trolley, furniture, machinery parts, such as precision machining with tube, rod, shaped material, plates
2.6063 used in building material, irrigation pipe, and for vehicle and bench extrusion materials, furniture, fencing, etc
3.7075 used in the manufacture of aircraft structures and futures He demanded high strength, strong corrosion resistance of high stress structure, mould manufacturing.