Material damage at high temperatures is being experienced in thermal power and chemical plants during long term service. This problem occurs in both low and high alloy steels of plants where the service temperature is from 450°C to 650°C, and it is suggested that this damage is caused by carbide precipitation in heat resistance steel.
The results of the present study are summarized as follows;
(1) Material damage (creep damage) during long term service in heat resisting steel is possible to be measured with the electric resistance method.
(2) Non-destructive diagnosis for damaged material can be made by determining the ratio of electric resistivity between the unused and used (damaged) materials.
