On the experimental and numerical study of formability of Aluminum sheet in warm hydroforming process

Aluminum alloys have high strength to weight ratio and Poor formability at room temperature is the main drawback of using these alloys. In order to overcome this limitation, the work material is formed at higher temperature. One of the forming processes is hydrodynamic deep drawing on which no relevant research has been reported in warm condition. In the present paper, after examining the formability of 5052 aluminum alloy in warm hydrodynamic deep drawing, the effect of media pressure, temperature and forming speed on thickness distribution and punch force in forming of flat-bottom cylindrical cups was investigated. In order to perform a complete investigation, the simulation of the process was established using ABAQUS software. It was illustrated that the results was in accordance with the experimental findings. It was also demonstrated that increasing the maximum oil pressure to a specified level could improve the thickness distribution and lead to increasing the punch force. The required punch force was decreased with increase in temperature but remained unchanged by punch speed variation. The maximum thickness reduction was decreased with increasing and decreasing of temperature and punch speed, respectively. Moreover, the forming of the sheet at room temperature, isothermal and non-isothermal warm forming processes was compared. It was concluded that the maximum thickness reduction in the formed part was less in the cases of cold forming and non-isothermal warm forming than the isothermal warm forming. But the required forming force is decreased in isothermal warm forming when compared with the other two conditions.