The result of test on intercrystalline corrosion of Incoloy800H heat transfer tubes used for steam generator in nulcear power plant under different conditions of sensitization has been analysed.Results show that the remarkable intercrystalline cracks have not appeared on sample

which were directly being tested and hadn't carried out any sensitization treatment

however

macroscopic cracks have occurred in different degrees on samples after sensitization treatment

and the longer the sensitization time was

the more severe tendeny of cracking had.In order to enhance the intercrystalline corrosion resistant ability of Incoloy800H heat transfer tubes

the C content has to be reduced

and the Ti content has to be increased

at the same time

the environment of mediums should be strictly controlled

so as to avoid the interstalline cracks occurred on the heat transfer tubes.