What is the difference between 6061 and 7075 aluminum?

 　　The main difference between 6061 and 7075 aluminum lies in the following properties:

　　Alloy series and chemical composition

　　Mechanical properties

　　Manufacturing precautions

　　application

　　Alloy series and chemical composition

　　The first difference between 6061 and 7075 can be immediately found by looking at their numbered names. 6061 belongs to the 6XXX series aluminum alloy grade, and 7075 belongs to the 7XXX series. Knowing this, without even delving into their individual material data sheets, it can be inferred that 6061 will have higher silicon content and 7075 will have higher zinc content. When checking the exact range of two individual alloys, it can also be noted that both contain a large amount of magnesium, although the magnesium content of 7075 is slightly higher. 7075 also added more copper to its chemical composition.

　　Mechanical properties

　　6061 and 7075 are both heat treatable, so it is impossible to accurately compare their mechanical properties without assuming the same type of heat treatment. When observing two alloys under - T6 conditions (meaning solution heat treatment followed by artificial aging), several significant differences were observed. Firstly, the tensile strength of 7075-T6 is almost twice that of 6061-T6. The shear strength of 7075-T6 is approximately 6061.6 times that of 1-T5. The former is also more difficult.

　　Manufacturing precautions

　　When manufacturing two types of aluminum alloys, 6061 almost always has an advantage over 7075. This is mainly due to the lower hardness and tensile strength of 6061. The lower hardness makes it easier to machine than 7075. The lower tensile strength means that 6061 is easier to form than 7075. Although both materials can be connected by welding, brazing, or adhesive, 6061 is weldable, while 7075 is usually considered non weldable. Although 6061 is considered weldable, attention must be paid to selecting suitable welding filler metals. Post weld heat treatment and aging may be required to restore the welding area to its original "- T" name. 7075 is prone to cracking after welding.

　　application

　　There are many overlapping applications between 6061 and 7075 aluminum alloys. As mentioned earlier, both are structural grades of aluminum. Both are used for bicycle parts, aerospace components, and construction. However, their usage in these fields varies. For example, in the aerospace industry, 7075 may be more likely to be used as a gear or rod, while 6061 may be more likely to be implemented in areas requiring more ductility. For bicycle parts, some riders prefer the higher strength brought by 7075 aluminum alloy. 7075 is more likely to be used for molds and industrial tools than 6061. Due to its easier molding than 7075, 6061 is more commonly used for tanks and other shapes with circular contours.