Aluminum is a familiar material used in a wide variety of industrial sectors for its lightweight and good workability in such applications as daily necessaries, functional parts, and structural materials.
Aluminum alloys are available in wrought products in the form of sheet, wire, rod, pipe, and rod and castings in the form of sand mold, permanent mold casting, and die casting for a variety of applications.In terms of strength, aluminum alloys are divided into heat-treatable and non-heat-treatable materials.These may be summarized in the table shown below.

JISsymbol Pure aluminum (AL) High purityAL 99.9%or more A10×× Industrial pureAL 99.8%AL A1××× 99.7%AL 99.5%AL 99.0%AL Aluminum alloys Non-heat-treatable alloys AL-Mg based A3××× AL-Si based A4××× AL-Mg based A5××× Heat-treatable alloys AL-Cu based A2××× AL-Mg-Si based A6××× AL-Zn based A7××× Non-heat-treatable alloys PureAL based     AL-Si based alloys   AC3Aetc AL-Mg based alloys   AC7Aetc Heat-treatable alloys AL-Cu-Si based alloys   AC1A,ADC12 Al-Cu-Mg-Si based alloys   AC4D,ADC14 AL-Mg-Si based alloys   AC1B,ADC3

As summarized above, aluminum metal is available in a variety of types, which vary greatly in chemical properties.Since not only aluminum is active but also many aluminum alloys contain inactive elements such as silicon, aluminum alloys require different pretreatment from that for steel and copper alloys.
Precautions are listed below.