Papers by Author: Grzegorz Golański

Abstract: The paper presents results of research on the influence of ageing on the microstructure and mechanical properties of T24 steel. The examined material was in the form of longitudinal samples taken from a pipe section (with the pipe size of 44.5x6.7 mm). The research is focused on degradation of the base material (T24 steel) where the steel samples, after initial heat treatment, were aged at the temperature of 580°C and time up to 6000hrs in a furnace with air atmosphere. This contribution summarizes the experimental results of mechanical and structural measurements and provides relations between them.

Abstract: The paper presents results of research on the influence of regenerative heat treatment on structure and properties of G17CrMoV5 – 10 cast steel. Investigated material was taken out from a turbine frame serviced for over 250 000 hours (total service time) at the temperature of 535 oC. The cast steel after service revealed degraded bainitic-ferritic structure and was characterized by mechanical properties ranging below norm requirements. It has been proved that high tempering temperature in the case of cast steel with bainitic structure ensures optimum combination of mechanical properties and impact energy. It has also been shown that ferrite has a negative influence on impact energy of the cast steel with bainitic-ferritic structure.