Room and high temperature deformation behaviour of a forged Fe–15Al–5Nb alloy with a reinforcing dispersion of equiaxed Laves phase particles

The cast-in network of continuous Laves phase in a Fe–15%Al–5%Nb alloy has been converted to a dispersion of coarse Laves phase particles by high temperature forging, and the room temperature and high temperature deformation behaviour examined. The material shows good room temperature tensile ductility and good creep strength at temperatures up to 700 °C. The good high temperature strength is explained by the refinement of substructure by the dispersion of Laves phase particles and load and strain partitioning between the stiff and hard phase and the softer matrix. The relatively coarse microstructure is expected to be highly stable against coarsening at high temperatures, which should allow retention of creep properties even for long exposure times.

► Forged Fe–15%Al–5%Nb has a composite structure of soft matrix with equiaxed Laves phase particles.
► The material shows good strength with excellent ductility at room temperature.
► Good creep strength is maintained to 700 °C.
► The coarse composite microstructure ensures good long term stability at high temperatures.
► High temperature strength depends on load sharing between phases and microstructural refinement.