TREATMENT OF LOW STRAINS AND LONG HOLD TIMES IN HIGH TEMPERATURE METAL FATIGUE BY STRAINRANGE PARTITIONING

摘要

In this report we have attempted to outline a simple procedure for treating creep-fatigue for low strainranges and long hold times. We have suggested that a semi-experimental approach, wherein several cycles of the imposed loading is actually applied to a specimen in order to determine the stable hysteresis loop, can be very useful in the analysis. Since such tests require only a small fraction of the total failure time, they are not inherently prohibitive if experimental equipment is available. It is, in fact, a simple method of by-passing the need for accurate constitutive equations since the material itself acts to translate the imposed loading into the responsive hysteresis loops. When Strainrange Partitioning has been applied in such cases very good results have been obtained.