ملخص البحث :

When performing the actual additional sheet forming procedures, it is expected to be exposed to Tool failure and physical failure. So, the risks should be within their minimums. This research aims to predict material failure as well as tools. The quantitative and hypothetical method was adopted as a controller of the solid formation and weight parts formation. Overlay sheet metal forming strategies define boundaries. The use of progressive sheet materials makes new hard tasks simulate procedures due to the formability of materials strengthens associated with classical steel metal. The following may cause a fractured challenges situation may occur information action, also It has been faced nonharmony case in materials forming possessions supplied by the deferent vendors. Moreover, the other challenge is represented through high interacted stress with high heat throughout formatting processing, which leads to a reduction in the tool's life. The maximum forming ability and the large tendency of formed elastic material to revert before forming leads to inaccuracy of the dimensions in the part that has been formed before.

ملخص البحث :

This paper presents a study of free vibration of perforated laminate composite plate. The modal characteristics consist of three layers, the material is hard orthotropic composite material, with simply support (SSSS), Clamped boundary (CCCC) and simple clamed conditions (SCSC) are applied at all four edges of the plate.. The natural frequency and mode shape of the plates have been obtained using ANSYS 15. Eight-node isopaprametric layered shell elements (SHELL 281) are employed in the modeling for describing the vibrations of these perforated laminate composite plates. The effect of number of holes, hole area ratio, lamination angles and boundary condition on vibrations are investigated. The convergence study was achieved for numerically and compare with present literature. The results showed that the frequencies of the plate with one hole at the center are different from the perforated plate when maintaining a fixed ratio hole area, as well the lamination angle has a clear effect on the increase and decrease of the fundamental frequency for all the tested cases.