Microstructure and properties of Al-Cr porous intermetallics fabricated by thermal explosion reaction

•Al-Cr porous intermetallics are synthesized by thermal explosion reaction.•Al-Cr porous intermetallics have high open porosity and low density.•Al-Cr porous intermetallics have superior oxidation resistance. Al-Cr porous intermetallics were fabricated by thermal explosion (TE) reaction. Microstructure (phase composition and pore characteristics) and properties (expansion behavior, density and oxidation resistance) of Al-Cr sintered products were investigated. Results showed that the sintered products retained their original cylindrical shape with an obvious expansion behavior and high open porosity. The interconnected pores were mainly inherited from green compacts or come from the diffusion of liquid Al and volume expansion. The phase compositions of the specimen with Al:Cr = 8:5 and 9:4 were mainly Al8Cr5 with minor Al4Cr (in the specimen with Al:Cr = 9:4), Al2O3 and unreacted Cr. The intermetallics of the specimen with Al:Cr = 8:5 had superior oxidation resistance.