Effect of service on microstructure and mechanical properties of Nb-stabilised austenitic stainless steel

The article presents the results of investigations of the microstructure and mechanical properties of austenitic, creep-resistant TP347HFG steel in delivery condition and after operation at 585 °C. As-received, the tested steel is characterised by an austenitic structure with twins and NbX precipitates. The conducted studies showed that the operation resulted in precipitation processes, mainly at grain boundaries, where M23C6 carbides and σ...