Abstract
The application of the back-torsion process to the strengthening of aluminum alloy pipes was examined in this study. The results showed that this process was useful for both alloy pipes for working and those for aging. The most outstanding characteristic of this method is that the strengthening of the materials can be adjusted by simply adjusting the number of twists without the use of dies or core bars, which are necessary for the conventional drawing process. Also, it was determined that the cross-section hardness of pipes with back-torsion treatment gradually increased from the inside toward the outside of the pipe, while the pipes treated by the drawing process had an M-shape distribution.
