Determining the stress-strain state during the spherical indentation in the metastable austenite

Podnice tlačnih posod se izdelujejo s plastičnim preoblikovanjem materiala, zaradi česar pride do spremembe mikrostrukture materiala in površinske trdote. V magistrski nalogi je bila opravljena analiza vpliva sile vtiskanja kroglice na stopnjo deformacije oz. plastičnega preoblikovanja materiala. Najpomembnejši del so bile laboratorijsko izmerjene vrednosti Vickersove trdote v primerjavi z ročno izmerjenimi vrednostmi trdote po Brinellu. Namen naloge je bil oceniti, ali je možno z meritvijo trdote spremljati deformacijsko stanje metastabilnega avstenita in uporabiti dobljeno kalibracijsko krivuljo pri meritvah na posodah v obratovanju.Production of pressure vessel cups with the plastic deformation of the material changes the microstructure of the material and surface hardness. In the Master thesis the analysis of the influence of force during the spherical indentation and plastic deformation of the material was made, respectively. The most important parts are the laboratory measured values of Vickers’s hardness in comparison to the hand measured values according to Brinell. The aim of the work was to estimate the possibility of monitoring the deformation state of the metastable austenite with the measurement of hardness and to use the obtained calibration curve by the measurements on cups in operation