What are the properties and applications of 7075 aluminum pipe

Aluminum pipe

What are the properties of 7075 aluminum pipe, and what is the difference between them and other series of aluminum pipes? Next, an excellent aluminum pipe manufacturer JIANGSU TISCO INDUSTRIAL CO., LTD will introduce the properties of 7075 aluminum pipe to you.

Application of aluminum pipe

7075 aluminum pipe is an aluminum-zinc-magnesium-copper series heat-treatable high-strength deformable aluminum pipe. It is the veteran of super duralumin, but it is not a big one, because there are still stronger ones, and it can be used to process all of them. Semi-finished products are used to manufacture various structural parts, especially aerospace structural parts. It is the most widely used high-strength aluminum pipe today, as large as the front fuselage stringer of the C919 large aircraft, passenger observation window frame forgings, medium Fuselage sheet bending, and girders, keel beam webs, floor turning beams, middle and rear fuselage girders, passenger observation window frame forgings, cargo cabin door frames, nose front pressure frame flanges, cabin door frames, etc.; small to mobile phone casings. It has a variety of heat treatment states T6, T73, T76, and T77. T6 state materials have the highest mechanical strength properties, but their fracture toughness is low, they are sensitive to stress corrosion, and their toughness decreases with the decrease in temperature. Therefore, T6 state materials are not suitable for manufacturing low-temperature structural parts and workpieces; T73 materials have the lowest strength but have quite a high fracture toughness, good stress cracking resistance, and exfoliation corrosion resistance; the strength of T76 material is higher than that of T73 material, and its resistance to stress corrosion cracking is higher than that of T6 material. The static strength performance of 7075 aluminum pipe is higher than that of 2024 and 2124 aluminum pipe, and the fatigue performance is equivalent to it. O-state and W-state materials have good room-temperature formability.

Aluminum pipe performance

7075 aluminum pipe can be resistance welded, and the long-term working temperature of the workpiece is ≤125°C. Incomplete annealing specification for materials or workpieces is 290°C~320°C, heat preservation for 2h~4h, and then air cooling out of the furnace; complete annealing specification (390~430)°C/(0.5~1.5)h, with a cooling rate not greater than 30°C/h Cool to ≤200°C, then air cool.

The solution treatment temperature of 7075 aluminum pipe is 460°C~490°C, and the treatment temperature of the aluminum plate should be close to the lower limit, and the number of repeated treatments should not be more than 2 times, so as to prevent the aluminum pipe elements from diffusing through the aluminum clad layer and reducing the corrosion resistance of the material Performance; the heating temperature of the extruded material is 460°C~471°C. After heat preservation, quench in room temperature water or warm water or another suitable cooling medium, and the transfer time should be less than 15s.

Thick plates and extruded profiles will produce a lot of internal stress after quenching and must be stretched before aging treatment to reduce it to the allowable range, so this stretching is called pre-stretching, pre-stretching The amount is 1.5%~3%, otherwise serious deformation will occur. The thermal conductivity of the material is related to its state. At 25°C, the thermal conductivity of the T6 material is 124W/(m·°C), while that of the T73 material is higher at 156W/(m·°C). The specific heat capacity (at 25°C) of 7075-T6 aluminum pipe is 796J/(kg·°C). The density of 7075 aluminum pipe is 2.8g/cm3, the resistivity at room temperature is 57.4nΩ·m, and the electrical conductivity is related to the state of the material. The T6 material is 17.7MS/m~20.6MS/m, and the T73 and T76 materials are 22.0 MS/m~24.4MS/m.

Advantages of 7075 aluminum pipe

Like other aluminum pipes, 7075 aluminum pipe has strong oxidation resistance, and its resistance to general corrosion is equivalent to that of 2024 aluminum pipe except for stress corrosion. 7075-T6 aluminum pipe is extremely sensitive to stress corrosion cracking, especially in the transverse direction (ST), while the performance of T73 and T76 materials has been greatly improved. T73 material has the highest resistance to stress corrosion cracking, while T76 material not only has high strength but also has high resistance to stress corrosion cracking and exfoliation corrosion.

The above is the introduction of the properties and applications of 7075 aluminum pipe. Interested friends are welcome to pay attention to JIANGSU TISCO INDUSTRIAL CO., LTD for more information about steel.