Zrychlené ochlazování tyčí na laboratorní polospojité válcovně

Abstract

The main aim of this bachelor thesis was to verify a possibility of the Ni3Al powders compaction crammed in a sealed thin-walled steel pipe and to experimentally investigate an influence of the subsequent intensive deformation for the structure development. The experiment was carried out on the semi-continuous rolling mill at the VŠB - TU Ostrava. For the powder compaction were selected the heating temperatures 900 - 1200 ° C. There were obtained the round bars, by rolling on the continuous finishing train, with the diameter 12.8 mm. The heating temperature 1000 °C was found to be the best in terms of the resulting properties, since the cavities occurrence was smallest. Another experiment consisted from samples rolling between flat rolls with the deformation 58%. The results show that the bars compacted at lower rolling temperatures (900 - 1000 °C) can be further formed without the cohesive failure and with reduction the crack occurrence. The structures compacted at 1100 °C and 1200 ° C and subsequently rolled led to the large cracks presence.