| The lightweight design of automobile has received more and more attention, because of the continuously improvement of the energy saving requirement. Aluminum alloys is a kind of material with a series of advantages, such as low density, high specific strength and corrosion resistance. But the formability of aluminum alloys at room temperature is bad, that limits the application of aluminum alloys as the lightweight material in the automobile industry.An effective way to solve the problem is to form the aluminum alloys at high temperature, because the formability of aluminum alloys could be greatly improved at high temperature, so the investigation of the formability and process of aluminum alloys at high temperature is of important practical value.The paper focused on the investigation of the formability of 5754 aluminum alloys at high temperature. The main content has been shown here.To do uniaxial tensile test of 5754 aluminum alloy sheets at different temperature and strain rate, in order to investigate its stress-strain curve and elongation at different temperature and strain rate. And the constitutive relation of 5754 aluminum alloy sheets is also studied. Then the modules of hot deep drawing is designed to investigate the limiting drawing ratio of 5754 aluminum alloy sheets at different temperature, and the influence of stamping speed and holding time on the formability of 5754 aluminum alloy sheets is also studied. To verify the accuracy of CAE simulation of hot stamping process of aluminum alloy sheets, the hot drawing process of 5754 aluminum alloy sheets is simulated. Finally, the process of hot stamping of a practical auto parts is simulated to preliminarily verify the feasibility of hot stamping of aluminum alloy sheets.By the previous investigation, the results obtained are mainly as follows. The stress-strain curve, elongation of 5754 aluminum alloy sheets at different temperature and strain rate is obtained. And the constitutive relation of 5754 aluminum alloy sheets is also obtained, that could provide material parameter for CAE simulation. The limiting drawing ratio of 5754 aluminum alloy sheets at different temperature is obtained, and the regularity of the influence of stamping speed and holding time on the formability of 5754 aluminum alloy sheets is also obtained.By comparing the diameter of the flange portion and the thickness distribution of the formed part, the accuracy of CAE simulation is verified. And the results of CAE simulation show that the process of hot stamping of aluminum alloy sheets is feasible to form auto parts. |
