The purpose of the master's thesis was to investigate the influence of the deformation degree on the mechanical properties of cold-drawn PT929 steel. From pre-hot rolled and heat-treated coils of wire with a diameter of D = 8 mm, rods of different dimensions were drawn, achieving different degrees of deformation (0.09, 0.16, 0.32, 0.41, 0.48). With the help of tensile test, we determined the mechanical properties of steel according to the deformation degree (yield strength, tensile strength, elongation, contraction). We performed microhardness measurements and metallographic analysis on a light microscope. We found that the average measured values of yield strength, tensile strengths and hardness increase with increasing strain ratehowever, the average measured values of elongation and contraction are decreased. We confirmed that the steel has martensitic microstructure before and after drawing. We also proved the decarburized layer formed during the fabrication of wire coils.
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