Results of a low cycle fatigue inter-laboratory comparison on 1CrMoNiV rotor steel at elevated temperature

Abstract

Following an initial intercomparison investigation carried out under a VAMAS programme, a similar venture has been carried out on a single source of 1Cr rotor steel at 525°C at a single total strain range of 0.5% and reversed strain rate of 6%/min (103/s). A key difference was that, for each specimen prior to testing at high temperature, bending measurements were performed at room temperature as a check on unixial alignment since this parameter had previously been suggested as a source of scatter in endurance. Fifteen laboratories participated in the comparison and 67 test results have been subjected to statistical analysis. There appeared to be no consistent effect of the magnitude of bending strain but it is concluded that a minimum of five repeat tests are required from each establishment for meaningful analyses to be made.