FINITE ELEMENT INVESTIGATION OF INFLUENCE OF SELECTED FACTORS ON ECAP PROCESS
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Particularly during the last decade an intense development occurred in use of computer simulations for materials forming. This was caused among others also by the necessity of acquiring more detailed information on temperatures and also on deformation – strain relationships during forming processes. Numerical modelling is used both for classical forming methods and also for unconventional forming methods. The presented paper is focused on mapping of influence of tool geometry, friction factor, strain rate, analysis of flow or applied temperature in ECAP technology. Copper was used as experimental material. During experiment matrices with an angle Φ = (110°, 60°, 30°) were simulated, as well as rates of extrusion v = (3, 10, 30) mm.s -1 . It emerged that while the peak value of temperature increases with the increasing rate of extrusion, the same dependence is not valid for value of the angle Φ. Defined friction influenced among others also the shape and magnitude of the dead zone. Its influence was evident also on magnitude of deformation and its distribution. Technologies based on application of severe plastic deformation (SPD) at forming became during the last decade - thanks to the research realised in this field – very widespread tool for obtaining ultra-fine grained materials. It is evident from the existing works that process of grain refining is connected with dislocation
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