A novel fabrication strategy for highly porous FeAl/Al2O3 composite by thermal explosion in vacuum

The high porosity of FeAl/Al2O3 composites was successfully prepared via a low-energy consumption method of thermal explosion (TE) in vacuum from reactant mixtures of Fe, Al and Fe2O3. The temperature profiles, phase compositions, microstructure, porosity and pore size of the products were investigated. The TE reactions were ignited between 639 and 648 °C and maximum combustion temperatures reached to 1196-1867 °C. XRD patterns showed that FeAl, Fe2Al5 and Al2O3 were formed via TE reaction, and FeAl and Al2O3 were evolved as dominant phase after the final sintering at 1100 °C. The FeAl/Al2O3 composites exhibited an interconnected pore structure with porosities and pore size of 52-61% and 27-32 μm, respectively.