Abstract
A graded metallic membrane composed of Fe, Ni and Cr was developed for microfiltration devices via thermal route of simultaneously sintering–reduction techniques. Porous Fe–Ni alloy powder has been fabricated by simultaneous reduction–sintering reactions of iron oxide/nickel oxide mixtures. Screen printing technique was used for the deposition of the mixed powder on the steel substrate layer. The formed phases were identified by X-ray phase analysis. The produced powder was characterized by reflected light microscope and scanning electron microscope along with energy-dispersive X-ray spectroscopy (EDX). The microstructure changes accompanying sintering–reduction processes were investigated under different experimental parameters such as temperature, holding time and gas composition. The results show that pure Fe0.64Ni0.36 with relatively high porosity can be fabricated via reduction route. The presence of NiO plays a significant role in the reduction of iron oxide as well as in the structural changes accompanying the reduction processes. The particle size distribution of the produced metallic materials is being controlled under the different operation conditions to get a homogenous porous metallic structure with well defined porosity.
► Metallic membrane composed of Fe, Ni and Cr is developed for filtration devices. ► Pure FCC Fe0.64Ni0.36 can be fabricated via reduction–sintering route. ► Porous ferroalloy layer can be achieved on steel substrate. ► Reduction–sintering behavior of metal oxides was discussed.