Fine surface microstructure of Fe3Al alloy after severe plastic deformation

Fe3Al alloy with nominal composition 73Fe-25Al-2Cr (at%) was subjected to surface mechanical attrition. The fine structures of surface grains on the Fe3Al alloy, which undergone severe plastic deformation, were studied. The results show that nanocrystals about 50 nm in average are produced on the top surface when Fe3Al alloy undergoes 5 min attrition. Moreover, some submicron grains about 100-300 nm in size are induced because of the nonuniform strain. The refinement of grains is controlled by dynamical recrystallization mechanism for Fe3Al alloy under the condition of severe plastic deformation. The grain refinement leads to the strengthening of Fe3Al alloy and the peak hardness reaches HV425 after 5 min attrition.