a new method for determination of residual stresses in the bottom layers of laminated composites is developed. in this method the residual stresses are determined by performing a consecutive drilling of laminated composites in the center of the rosette and recording the strains after drilling each layer. the depth of the hole in each step is equal to the thickness of each layer and the maximum ...

The aim of this study is to investigate the effects of temperature and thermal residual stresses on the impact behavior and damage of unidirectional glass/epoxy laminated composites. To this end, thermal stress analyses of the laminates with lay-ups [90/0/0/90]s, [90/0/45/45]s, [0/90/45/-45]s were carried out under temperatures of 20, 90 and -50 °C by using ANSYS software. Damage parameters pro...

The deformation of polycrystalline beryllium to strains of 60.8 pct in uniaxial tension and compression was studied by neutron diffraction and modeled using an elasto-plastic self-consistent (EPSC) model. The beryllium response is asymmetric with respect to tension and compression in both the macroscopic behavior, as displayed in the stress/strain curve, and the microscopic lattice response. Th...

Many researchers content themselves with the 2D simulation of welding process instead of the 3D simulation, because of the time and the cost factors of the latter. In this research, the number of elements and nodes are reduced by an initiative plan (defining an equivalent model) for the simulation of welding. The welding process has been simulated by an uncoupled thermal-mechanical finite eleme...

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We observed residual stress relaxation by CO(2) laser irradiation in the cores of optical fibers by direct stress measurement. It was demonstrated that the mechanical stress was fully relaxed by CO(2) laser irradiation and that the remaining stress in the core was thermal stress that was due to a mismatch of the thermal expansion coefficients of the fiber core and cladding. The net core stresse...

-The present investigation is based on the effect of thermal residual stresses on the both thermal expansion and damping behavior of Al/Al2O3 Metal Matrix Composites (MMCs) processed by compo casting. Thermal expansion and damping properties have been studied experimentally as a function of temperature over a temperature range from room temperature to 400°C both in the heating and cooling cycle...