High-cyclic failure analysis of welded cast iron plates

Abstract

The article presents experimental analytical research results of seminatural welded cast iron specimen. It has been determined: the chemical structure of the base and weld material, static mechanical properties, hardness and microstructure. The static loading during the experiment is started from a close to structural elements loading. The investigation starts from a given stress changing programme. The experiment was performed according to the given programme on stress changing. The kinetic fatigue diagram is performed according to the experimental data. For determining the failure conditions an additional fracture analysis has been performed. The investigation was supplemented by cast and normalised CT samples experimental data analysis by applying the crack growth rate versus stress intensity factor range diagram as well as by the crack opening diagram. Values of limiting stress factors Kth and KC have been determined.