Stress determination in a thermally grown oxide on Ni38Cr alloy by use of micro/nanogauge gratings

Abstract

Abstract Residual stresses in thermal oxide layer may be significant and can influence the lifetime of systems in high temperature environments. It is thus relevant to determine locally stress and strain mechanisms and especially the mechanical relation between the oxide layer and the metallic substrate. To achieve such a goal, an innovative approach is proposed by use of micro/nano-gratings. Monitoring experimentally the gauges displacement during high temperature oxidation and considering a specific model, we are able to determine thermomechanical quantities both in oxide Cr 2 O 3 and in metallic alloy Ni38Cr, as well as their evolution during the oxidation time. Parameters values for calculations of the stress versus time evolution are also provided.