Analysis of the elevated temperature deformation mechanisms and grain boundary strengthening of the alumina-forming austenitic stainless steel Fe–20Cr–30Ni–2Nb–5Al

The deformation mechanisms of an alumina-forming austenitic stainless-steel Fe–20Cr–30Ni–2Nb–5Al (at. %) were investigated at 750 °C using both creep tests and strain rate jump tests. It was found that nano-sized L12-structured precipitates the dominant precipitate in matrix provided majority strengthening. This behavior could be modeled well a threshold stress term power law equation. Additionally, there appears to grain boundary strengthening mechanism which boundaries covered by act as barriers dislocation movement. again In addition blocking dislocations, also prevent sliding during creep. While showed several mechanisms, all ultimately failed along boundaries.