Ni-Sn porous metals with different concentrations of Sn were prepared as potential current collectors for solid oxide fuel cells (SOFCs). The weight increase of these species was evaluated after heat-treatment under elevated temperatures in air for thousands of hours to evaluate the long-term oxidation resistance. Ni-Sn porous metals with 5-14 wt% of Sn exhibited excellent oxidation resistance at 600 degrees C, although oxidation became significant above 700 degrees C. Intermetallic Ni3Sn was formed at 600 degrees C due to phase transformation of the initially solid solutions of Sn in Ni in the porous metals. For the porous metal with 10 wt% of Sn, the oxidation rate constant at 600 degrees C in air was estimated to be 8.5 x 10(-14) g(2) cm(-4) s(-1) and the electrical resistivity at 600 degrees C was almost constant at approximately 0.02 Omega cm(2) up to an elapsed time of 1000 h. In addition, the gas diffusibility and the power-collecting ability of the porous metal were equivalent to those of a platinum mesh when applied in the cathode current collector of a SOFC operated at 600 degrees C. Ni-Sn porous metals with adequate contents of Sn are believed to be promising cathode current collector materials for SOFCs for operation at temperatures below 600 degrees C. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.