Experimental study of cyclic creep of AISI Type 347 stainless steel in temperature range 100-250 deg C

It is shown in this experimental study that type 347 stainless steel exhibits very significant strain ratchetting when it is stress cycled, whether continuously or with peak stress dwells, in the temperature range 1000C to 2500C. This is attributed to the phenomenon of cyclic cold creep which has also been reported in types 304 and 316 stainless steels by other workers. Some features of this cold creep are noted and whilst they differ from high-temperature creep in a number of ways, electron-micrographs of the strain ratchetted specimens show them to possess a dislocation cell structure within the grains similar to that in type 304 stainless steel which had been subjected to high temperature low cycle fatigue loading. (author)