The formability of light-weight alloy, such as aluminum alloy, magnesium alloy, can be improved significantly when formed at elevated temperature. Superplastic forming (SPF) is a well-known manufacturing method to form complex part of these materials. In order to realize mass production of SPF in industry, forming at high strain rate should be realized. In this study, the mechanical properties of 5A06 sheet were tested by uniaxial tensile test at high strain rate and elevated temperatures up to 550 ℃. Free bulging test and forming of round cup were carried out to evaluate the formability of the 5A06 sheet. Results show that the total elongation of the 5A06 sheet began to increase rapidly after 200 ℃, and reached the maximum value at 450 ℃. At higher temperature, early brittle fracture occurred. In free bulging test, the bulging height remained almost constant about 27.0 mm, which means the formability of the sheet is not sensitive to forming temperature at elevated temperature. In the forming of round cup part, temperature has direct effect on the corner filling ability of the sheet, especially at temperature lower than 400 ℃.
He Zhubin, Fan Xiaobo, Xu Yongchao, Yuan Shijian Harbin Institute of Technology, Harbin 150001, China
