Effect of 4 wt.% Cr on microstructure, corrosion resistance and tribological properties of Fe3Al-20 wt.%Al2O3 composites

Fe3Al-20 wt.%Al2O3 ultrafine grained composites with 4 wt.% Cr were prepared by mechanical alloying inducing self propagating high temperature synthesis with subsequent plasma activated sintering. Microstructures of the composites were studied by X-ray diffraction, scanning electron microscopy, energy dispersive spectrum and transmission electron microscope. Then the relative density, room temperature hardness, static corrosion resistance and dry sliding wear behavior at a temperature range of 25 degrees C-800 degrees C of the sintered samples were tested and analyzed. The results showed that the composites had high hardness and a good microstructure with fine grain size, high relative density. The composites with 4 wt.% Cr amount also exhibited excellent comprehensive tribological properties at medium-high temperatures especially at a temperature above 500 degrees C, although the wear resistance did not be improved at 25 degrees C-500 degrees C. 4 wt.% Cr element addition improved the corrosion resistance of the composites significantly with the corrosion loss decreasing by 19.48%. (c) 2013 Elsevier Inc. All rights reserved.