Using the method of reverse engineering the objective of this thesis was to analyse dependence of polymer material from high strain rate. The samples were made by injection moulding method and tested by uniaxial tensile tests and pneumatic steel ball shooting. It was found out that mechanical properties of material were changed due to load and this proved dependency from high strain rates. Cowper-Symonds material model was used for numerical investigation to determine stress and strain in material during used load. It was found out that using conventional methods, polypropylene shows soft and tenacious nature, but using high speed and high load material shows high toughness and fragility. Using Cowper-Symonds material model for the simulations the result between simulations and pneumatic tests were compared. It can be concluded that the stress-strain results obtained from simulation are reliable. Our method showed strain rate dependency in range from 0,012 to 60 s-1.
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