Detection of plastic deformation and estimation of maximum value of residual stress in low carbon steel by X-ray stress analysis using statistical techniques
Residual stress distribution on plate-type tensile specimens of low carbon steel with applied plastic strains up to 6.45%has been measured by X-ray stress analysis. Standard deviation for the frequency distribution profile of the residual stress was calculated by statistical processing to estimate the amount of macroscopic plastic strain applied on the specimen. Since adequate understanding of the maximum value of the residual stress (σmax) has been important for the maintenance of the nuclear power reactor components, the σmax was also estimated from the limited number of the experimental data by statistics of extreme. It was found from above estimation that the X-ray stress analysis supported by the statistical techniques was a promising non-destructive evaluation (NDE) method to detect the plastic deformation and to estimate the σmax in S25C low carbon steel.