A new strategy to improve the creep strength of a novel G115 steel by accelerating the precipitation of nano-sized MX and Cu-rich particles.

A new thermo-mechanical treatment strategy is proposed to improve the creep resistance of a recently developed G115 steel. The goal of this strategy is to construct a favourable microstructure with superior thermal stability at high temperatures up to 650 °C. The improved creep strength can be ascribed to the reinforced interactions between dislocations and nano-sized MX and Cu-rich precipitates. Creep analysis suggests that these MX and Cu-rich particles exhibit more important contribution to the creep resistance than the M 23 C 6 carbides. Following this strategy, the creep rupture life of the G115 steel can be significantly prolonged by more than two times. [Display omitted] [ABSTRACT FROM AUTHOR]