抄録
In order to develop suitable non-destructive evaluation (NDE) methods for detecting the creep damage and estimating the residual life of the machine parts used at high temperatures, the metallurgical observations and hardness tests were conducted on the crept specimens and the long-term serviced samples of Cr-Mo-V Steel.
The results obtained are summarized as follows:
(1) The damaged grain boundary observation method, the void density method and the hardness method were proposed as the NDE methods based on the results of investigation on the crept specimens under the uniaxial constant stress condition.
(2) Moreover, these NDE methods were found to be applicable to the parts subjected to long-term service under a multiaxial stress state.
(3) Among these NDE methods, the damaged grain boundary observation method makes it possible to evaluate creep damage and residual life without creep rupture data. Therefore, this method is considered as the most suitable one.
(4) However, since the NDE inspection of actual components should be conducted as quick as possible, a proper combination of the above various NDE methods is recommended.
