Mechanism of yield strength anomaly of Alloy 617

Anomalous increase in tensile yield strength (YS) of Alloy 617 at 800 and 900 °C has been investigated using different analytical tools. The enhanced YS has been attributed to the formation and accumulation of Cr23C6 and Mo23C6 precipitates, and development of pinned dislocations, dislocation pile-ups, and subgrains in the vicinity of the grain boundaries.