Metalografické hodnocení struktury ocelí

Abstract

The bachelor thesis deals with metallographic evaluation of the structure of hypoeutectoid steel. The work is focused on the evaluation of the proportion of proeutectoid ferrite formed by the decomposition of austenite during isothermal annealing for 240 s at a temperature of 750 ° C depending on the austenitization temperature. The theoretical part deals with the preparation of metallographic samples for structure analysis. There is a qualitative evaluation of the structure, a description of the phases and their transformations in steel. Quantitative methods of image analysis evaluation for phase fraction determination and grain size determination are also described. The task of the practical part was to evaluate the amount of infused ferrite and the size of the austenitic grain by quantitative methods.