Numerical Damage Prediction and Experiments in Deep Drawing of Irregular Square Cup
Deep drawing is an important sheet metal forming process in the industry. The deep drawing of irregular square cup was investigated in this paper. To predict the damage of irregular square cup, different blank hold forces and blank shapes were studied in the numerical model. The experiment was carried out with the optimized blank force holder and blank shapes, the crack and thickness distribution were investigated. The results of the experiment accorded with those of the numerical simulations, which show the validity of the simulation to predict where the damaged zones will appear in the part during the deformation.
Effect of the blank holder force on drawing of aluminum alloy square cup: Theoretical and experimental investigation
In this study, the influence of AA5754-O material, an aluminum alloy, in forming the blank holder force (BHF) in deep drawing process has been investigated. For this purpose, a new experimental system has been prepared. By means of this system, deep drawing process can be implemented through applying variable forces in computer-controlled manner on the blank holder and sheet plate. The numerical model of forming with deep drawing process has been built up and analyzed via the LS-DYNA software. Cup depths, tearing and wall thickness variations of the experimental and numerical results have been compared. It has been observed that no earing and wrinkling have occurred in BHF's between 1.3 and 8 MPa in square deep drawing process, and that tears have occurred in forces exceeding 18 MPa. It has further been observed that the best forming has occurred at 5 MPa, and that the numerical and experimental model developed is in harmony with one another at a rate of 85%.
Investigation of scatter radiation of non-circular X-ray scan trajectories
Modern interventional X-ray devices are highly maneuverable and allow complex 3D imaging trajectories. New scan trajectories enable not only optimized object sampling but also introduce new approaches for dynamic 3D imaging. In this paper, we investigated the scatter radiation of two different scan trajectories. The scatter radiation was sampled by a rail setup with dosimeters at defined positions. After data analysis, contour maps were generated which show for four exemplary heights the scatter radiation distribution. The alternative scan trajectory showed smaller dose exposures at heights correlated to upper torso and head areas of a model physician. Keywords—Image acquisition, alternative scan trajectory, circular tomosynthesis, scatter radiation distribution