Effect of Cr content on microstructure and mechanical properties of annealed large-dimensional bulk nanocrystalline Fe–Al–Cr alloys by self-propagating combustion synthesis

Abstract

Large-dimensional bulk nanocrystalline Fe–Al–Cr alloys with different chromium contents (5, 10, 15 and 20 wt.%) were prepared by self-propagating combustion synthesis. After isothermal treatment at 1000 °C for 16 hours, the microstructure transformation and the deformation behavior of Fe–Al–Cr alloys were studied and discussed. After annealing, the nanocrystalline matrix of the alloys changed slightly, and the average grain size remained as approximately 20 nm. Owing to the changes in the distribution and shape of the second phase, the annealed nanocrystalline Fe–Al–Cr alloys with different chromium contents provided good plasticity and strength. The annealed Fe–Al–Cr alloy with 15 wt.% chromium achieved the best comprehensive mechanical properties.