Scale adhesion, scratch and fracture behaviour of different oxides formed on iron based alloys at 700 °C

The influence of different alloying elements in ferrous alloys on the cyclic high temperature oxidation kinetics at 700 °C and the mechanical stability (scratch resistance) of the oxides were examined. Formed oxide scales were investigated using different microscopic and analytical methods including scanning electron microscopy and X-ray diffraction. The mechanical stability and fracture behaviour were examined via scratch testing. Statistical analyses of the results indicate a high relevance of Cr, Ti and Si on the oxidation stability and scale adhesion, while Ni plays only a subordinate role within the oxidation of these ferrous alloys. The wear resistance is highly affected by the oxide layer structure, their mechanical properties and the ongoing cracking and spalling behaviour.