INTERPRETATION OF IMPRESSION CREEP DATA USING A REFERENCE STRESS APPROACH

A sound, mechanics-based approach has been developed to allow conventional creep data to be obtained from impression creep test data; the reference stress method was used, to analyse the results of axisymmetric finite calculations, for this purpose. The equivalent uniaxial stress was found to be 0.296 times the mean indenter pressure and the effective gauge length was found to be about 0.755 times the indenter diameter. These values correspond closely with those which have been obtained by fitting indenter creep data to conventional uniaxial creep data.