Effect of surface roughness on high temperature creep property of oxide dispersion-strengthened steel plate

The high temperature creep test of oxide dispersion-strengthened (ODS) steel plate was carried out by high temperature in-situ fatigue testing machine, and the influence of the surface roughness on the high temperature creep performance of ODS steel plate was analyzed. The results showed that with the decrease of surface roughness, the steady-state creep rate of ODS steel plate decreased, the creep life extended, and the number of surface cracks of steel plate after test decreased. The surface cracks of ODS steel plate were formed by the interaction of the longitudinally distributed scratches on the surface and the laterally distributed slip lines. With the extension of time, the cracks propagated and connected to each other, eventually caused steel plate to break.