Showing 3 results for Forming
E. Masoumi Khalil Abad, A. Ghazanfari, R. Hashemi,
Volume 3, Issue 4 (12-2013)
Abstract
In this study, an extended stress-based forming limit diagram (FLD) for prediction of necking based on the
Marciniak and Kucznski (M-K) model is represented and applied in tube hydroforming. The bulge forming
of a straight tube is simulated by finite element method and verified with published experimental data. This
adaptive simulation technique is based on the ability to detect the onset and growth of defects (e.g., bursting
and wrinkling) and to promptly readjust the loading paths. Thus, a suitable load path is determined by
applying Adaptive Simulation Method in ANSYS Parametric Design Language (APDL).
Majid Fallah Tafti, Ramin Hashemi, Mohammad Sedighi,
Volume 12, Issue 2 (6-2022)
Abstract
This paper aims to examine the influences of heat treatment on forming limit diagrams and mechanical properties of aluminum alloy AA6061 sheets with thicknesses of 1.5 mm. The uniaxial tensile and the micro-hardness tests are employed to specify the mechanical properties and their variations. The Nakazima test is performed to characterize the strain forming limits of this aluminum alloy. Comparison between the results of micro-hardness and forming limit diagrams indicates that by increasing the temperature up to the peaked ageing temperature, the strength of the alloy is increased, but the forming limits are decreased, and after the peaked aged in over the aged state, the strength is decreased and the forming limits are increased. The peaked-aging is touched in this specific alloy after 4 hours heat treatment at 180 oC.
Arman Mohseni, Javad Rezapour, Sina Gohari Rad, Reza Rajabiehfard,
Volume 12, Issue 2 (6-2022)
Abstract
Background: Hydroforming is employed in the manufacture of hollow monolithic products to reduce the number of joints. This method can reduce the weight and enhance the quality of fluid transfer parts in a vehicle’s hydraulic system. Hydroforming is a process in which parts are formed into the shape of a mold using fluid pressure. An important issue in this process is adopting an optimal loading path. Methods: In the present research, a drop hammer was used to implement the dynamic loading path in the tests. Accordingly, a single energy source was used simultaneously to provide axial feeding and internal pressure. To this end, designing a mold suitable for the dynamic loading path was necessary. Results: This numerical study investigates tubes’ deformation based on the applied impact and the amount of fluid in the mold. Moreover, axial feeding was provided with the help of different punches on the sides of the tube. Hence, the kinetic energy, amount of fluid, sealing, lubrication, and the material and thickness of the tube must be proportional for the correct forming of the tube. From the smoothed-particle hydrodynamics perspective, it is a meshless method based on interpolation that uses a particle system to examine the system state and predict fields such as displacement, stress, and pressure. Conclusions: One of the main observations of this research is that selecting side punches with a smaller central hole radius is proportional to the kinetic energy and the amount of fluid. that is effective in achieving the optimal loading path.
