The purpose of this master`s thesis was to investigate the effect of pass schedule and quenching temperature on material properties within the scope of one series of products and within the scope of one product. First, we investigated the effect of pass schedule. For each investigated pass schedule, we had different number of passes and different deformation rates for each pass. Final sum of deformation rates was the same for all pass schedules. With this experiment, we have analysed defects in the material as well as recovery and recrystallisation process. We also investigated the effect of quenching temperature on mechanical properties of the material. In the second series, bars were rolled and then quenched from different temperatures. After that, all bars were tempered according to SIJ Metal Ravne`s quality prescription. From each bar we have taken two samples. One from the front and one from the back of the bar. We have performed tensile test, toughness test and metallographic analyses on all samples. We have concluded, that both parameters had effect on mechanical properties, but neither had a significant effect on its own. If we look at the sum of all effects, then we can conclude that even a small deviation in process plans can cause large differences in material properties. We can conclude that minimum deviation occurs when forging is conducted according to 'one way' pass schedule and when quenching is performed from higher temperature. On the other hand, we obtained optimal results with combination of 'soft' and 'rough' pass schedule and medium quenching temperature.
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