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this paper, ballistic impact on sandwich panel with composite facesheet made of Glass/Epoxy and aluminum honeycomb core has been investigated experimentally. Ballistic impact test also carried out on Honeycomb and composite and the effect absorption energy by adding composite on two sides honeycomb is studied. By this model the influence of the components on the behavior of the sandwich panel under impact load was evaluated. Ballistic impact tests is carried out on the samples by flat-ended projectile with 8/5 gr mass and 10 mm diameter in difference velocities. Also, the contribution of the failure mechanisms to the energy absorption of the projectile kinetic energy was determined. The results show that honeycomb sandwich has more energy than when alone ballistic tests conducted on has absorbed and front cover compared with back cover sandwich structure has lower energy absorption. Also bigger than ballistic limit velocity absorbed the maximum amount of energy.

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Prediction of critical process parameters which causes bursting and its location in warm tube hydroforming is a key factor in hydroforming parts design. In this paper, ductile fracture criteria have been modified so that effect of variation of temperature and strain rate on fracture is considered in forming of aluminum AA6063 tubes. Calibration of modified ductile fracture criteria has been performed using uniaxial tension tests at different temperatures and strain rates. Also, fracture strain and fracture work have been obtained as functions of Zener-Holloman parameter. Tube hydroforming process of a square part has been simulated at high temperatures in Abaqus software and loading curves with various axial feeds have been used to deform the tube. Then, the formed corner radius before bursting has been predicted using modified fracture criteria. A subroutine has been written for using modified fracture criteria. A warm tube hydroforming setup has been fabricated and prediction of modified ductile fracture criteria is compared with experimental results at various temperatures. Results show that modified criteria determine the location of bursting well. Maximum of thinning occurs in transition zone which the tube loses its contact with die cavity. Also, modified Ayada criterion, rather than other criteria, predicts corner radius with little error at high temperatures. Thus, because of its precise prediction, modified Ayada criterion can be used to predict the bursting of aluminum tubes at elevated temperatures.