Evaluation of Elastic and Strength Properties of Ni-YSZ Cermets for Solid Oxide Fuel Cells Under Redox Cycling

Abstract

The effects of pore volume in Ni-YSZ cermets on their mechanical properties under redox cycling were examined using a small punch (SP) testing method. The volume fractions of pores Vp in as-sintered NiO-YSZ specimens were in the range of 0-30%, and with the Ni/YSZ mixture ratio of 50:50%. All the measurements were conducted at 800 C. For Vp>20%, the measured Young’s modulus and strength of re-oxidized NiO-YSZ cermets were almost close to those of the as-sintered cermets. The experimental result indicates that the appropriate selection of Vp is necessary for ensuring the mechanical properties during redox cycling.