The grade is representative in aluminum alloys, and the following is an example of 7075T651 aluminum plate grade. The first 7 represents the aluminum and aluminum alloy group - aluminum zinc magnesium alloys. Aluminum and aluminum alloy groups are divided into nine categories. Among them, aluminum and aluminum alloys of series 1, 3, 5, 6, and 7 are mainly used, while other series are less likely to be used in practical use.

Class 1: Series 1: Industrial pure aluminum

Type 2: Aluminum copper series alloys

Class 3: Aluminum manganese alloy

Class 4: 4 series: aluminum silicon alloy

Class 5: 5 series: aluminum magnesium series alloys

Category 6: 6 series: aluminum magnesium silicon alloy

Class 7: 7 Series: Aluminum zinc magnesium copper series alloys

Class 8: Series 8: Other alloys

Class 9: Series 9: Spare alloys