Wrinkling behavior of the ultra-thin components with complex polygonal-sections during tube hydro-pressing process

The wrinkling behavior of the ultra-thin components during the tube hydro-pressing process was investigated by finite element analysis and confirmed by hydro-pressing experiment and the causes of various typical defects were explored. There are three typical wrinkle defects appearing on the part during the tube hydro-pressing process: transverse wrinkles, longitudinal wrinkles and oblique wrinkles. The transverse wrinkles are mainly caused by compressive stress perpendicular to wrinkles. The longitudinal wrinkles are mainly caused by tensile stress parallel to wrinkles. While, the oblique wrinkles are mainly due to shear stress.