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The present research deals with the impact response of notched aluminum plates repaired by fiber metal laminate (FML) patches under various temperatures using drop weight impact test status. Some aluminum samples repaired by FML patches were prepaired to study their impact behavior and frcture mechanisms under drop weight tests at the temperature range of -20 ℃ to 60 ℃. An Energy Profiling Diagram (EPD) was used to obtain the penetration and perforation thresholds of hybrid composites. Besides, the effect of temperature on some impact characteristics such as endurance load, contact time and permanent deflection were also studied. The results showed that the amount of force for nearly all of the samples increased by increasing of the room temperature. The ability of energy absorption of the samples was also the most at the room temperature, therefore the energy thereshold of samples increases by increasing of the room temperature. Temperature variation also affects on the impact characteristics of composites patches and in some cases results in a 20 percent reduce in impact strength of the samples. It was also shown that the most value of impact parameters reaches at -20 ℃ and 60 ℃.

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Today, with the development of technology, industries such as automotive and construction require products with variable cross section. Multiplicity of steps, dimensional limitation and high production costs of the components caused flexible roll forming process used to produce these products. One of the main defects in this process is the fracture phenomenon. The fracture is observed on the bending edges at transition zone that sheet thickness is large compared to the bending radius. In this research the fracture phenomenon is investigated on flexible roll forming process of channel section using ductile fracture criteria. For this purpose finite element simulation of the process using Abaqus software is done. The fracture defect in this process is investigated using six ductile fracture criteria by developing a subroutine. Experimental tests are performed on 27 specimens precut sheet of AL6061-T6, using flexible roll forming machine built in Shahid Rajaee University. By comparing simulation results with experimental results, numerical results were validated. In addition, by comparing the results of ductile fracture criteria with experimental results, the Argon ductile fracture criteria, was chosen as the most appropriate criterion to predict fracture. Also the effects of parameters as sheet thickness, bending radius and bending angle on fracture with argon selected criterion is studied.