Mechanisms of creep deformation in a rapidly solidified Al-Fe-V-Si alloy

Creep experiments on a rapidly solidified Al-8.5 wt% Fe-1.3 wt% V-1.7 wt% Si alloy (FVS0812) suggest that it exhibits similar or superior deformation resistance compared to other high temperature Al alloys. However, aging at 798 K for 200 h resulted in severe loss of creep strength. Stress reduction results show that FVS0812 exhibits similar creep characteristics to those of other dispersion-strengthened alloys under constant structure conditions following stress reductions, even though the creep mechanism is determined to be significantly different. The operational activation area analysis reveals that the rate-controlling obstacles to dislocation glide are dislocation-dislocation interactions. The role of the particles is to carry a portion of the applied load rather than causing dislocation detachment, local climb, or general climb. This result contradicts the validity of modeling the material using the Rosler-Arzt approach or relying on a threshold stress that is based on the increase in dislocation line length during local or general climb.

Automated summary

Creep experiments on a rapidly solidified Al-8.5 wt% Fe-1.3 wt% V-1.7 wt% Si alloy suggest that it exhibits similar or superior deformation resistance compared to other high temperature Al alloys. Stress reduction results show that FVS0812 exhibits similar creep characteristics to those of other dispersion-strengthened alloys under constant structure conditions following stress reductions, even though the creep mechanism is determined to be significantly different. The role of the particles is to carry a portion of the applied load rather than causing dislocation detachment, local climb, or general climb.