Investigation of average growth stresses in Cr_2O_3 scales measured by a novel deflection method

摘要

The stress in the oxide film plays an important role to keep it intact so it is necessary to determine the stress in the oxide scale. Average growth stresses in Cr 2O 3 scales formed on Ni base alloy (Ni80Cr20) at 1?000?℃ in air were investigated by a novel deflection technique. It is found that the growth stress in the oxide scale is basically compressive and its average order is 100?MPa. The stress values are high for the thin scales and become low for thick scales after oxidized for 10?h. The planar stress distribution in metals is complex. It is both compressive and tensile at the beginning of oxidation procedure, and then become only tensile during further oxidation.