Forming the straight flange of a rib by pulsed-magnetic field pressure

Abstract

In the production of aircraft, the most common method of manufacturing a straight flange is magnetic-pulse stamping, since it is highly efficient in small-scale production due to its high versatility and simplicity of technological equipment. Among the sheet metal parts of the aircraft, there is a fairly large number of parts with straight sides, which are made of a flexible elastic medium. In this paper, the straight flanging of the D16AM aluminum alloy during magnetic pulse forming was investigated by using the LS-DYNA simulation program. The operation of sheet bending is used to form the side wall of the part. If the bent side has a straight shape, then bending stresses occur along the bend radius, and the side wall remains unstressed. This operation is called «straight flange bending». With impulse shaping, there is a great possibility to control the shape of the workpiece during deformation by distributing pressure over its area. Excessive pressure is created on the workpiece after it adjoins the die. This pressure contributes to the redistribution of stresses and equalizes them along the height of the section of the workpiece, while inertial forces change the stress-strain state of the workpiece. This study, in particular, concerns an example of numerical simulation of the electromagnetic forming of a straight flange with the obtained mesh shape of a workpiece and the results of its calculations were summarized in the form of a nomogram.