In the master´s thesis we dealt with production of alloyed grey cast iron, which is resistant to thermal fatique and is suitable for use, both at room and at elevated temperatures. For the investigation we used feritte cast iron which is defined by the ISO EN-GJS-600-10 standard. We added molybdenum in order to compare machanical properties and simple thermal analysis (ATAS) was done. In the experimental work, 7 samples were manufactured from the same batch, on which thermal fatique tests were performed on the Gleeble 1500D physical simulator of metallurgical conditions. On the simulator, samples were tested at 600 °C and 200, 500, 1000, 2000, 4000 cycles. In order to provide smooth surface with no notch effect during cycling testing, the central hole of the specimens was made by electro erosion. Under the emission spectrometer, the chemical analysis of the samples was performed. The tensile test was performed on tensile test machine Inistron 5985 and the microstructure of the fractured surfaces was examined and analyzed. With optical and electron microscopy we analyzed the formation and progression of cracks, their orientation and density. With the final results we made a comparison between the individual temperatures and the number of cycles.
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