A. Pure aluminum (aluminum content not less than 99.00%)   1XXX
II. Alloy groups are divided by the following major alloying elements
1. Cu (copper)     2XXX
Mn(Mn)..
3. Si (silicon) Si (silicon) 
4. Mg (magnesium) î—¥ î—¥ î—¥ î—¥ î—¥ 5XXX
5. Mg+Si (magnesium + silicon)  
 6. Zn (zinc) 7.
7. Other Elements 
8. Standby group 
The 1XXX group represents pure aluminum (its aluminum content is not less than 99.00%), and its last two digits indicate the lowest two percent of the aluminum content behind the decimal point.
The second digit of the grade indicates the control of the limit content of alloying elements or impurities. If the second digit is 0, it means that there is no special control of the impurity limit content; if it is 1-9, it means that one or one The individual impurities or alloy elements above the item have special limits.
The last two digits of the 2XXX-8XXX brand have no special meaning and are only used to identify different alloys in the same group. The second digit indicates the modification condition. If the second digit is 0, it indicates the original alloy; If it is 1-9, it means modified alloy.
II. Alloy groups are divided by the following major alloying elements
1. Cu (copper)     2XXX
Mn(Mn)..
3. Si (silicon) Si (silicon) 
4. Mg (magnesium) î—¥ î—¥ î—¥ î—¥ î—¥ 5XXX
5. Mg+Si (magnesium + silicon)  
 6. Zn (zinc) 7.
7. Other Elements 
8. Standby group 
The 1XXX group represents pure aluminum (its aluminum content is not less than 99.00%), and its last two digits indicate the lowest two percent of the aluminum content behind the decimal point.
The second digit of the grade indicates the control of the limit content of alloying elements or impurities. If the second digit is 0, it means that there is no special control of the impurity limit content; if it is 1-9, it means that one or one The individual impurities or alloy elements above the item have special limits.
The last two digits of the 2XXX-8XXX brand have no special meaning and are only used to identify different alloys in the same group. The second digit indicates the modification condition. If the second digit is 0, it indicates the original alloy; If it is 1-9, it means modified alloy.