Recently, it has become important to estimate the strength of materials as many mechanical structures are being used under severe conditions. X-ray stress measurement is the only method which can be applied to analyze residual stress without destruction, and thus it is regarded as an effective means for investigating material strength.
In the present study, an automatic method of X-ray stress measurement was introduced and the data compiling and processing system for evaluation of stress was developed. The system was compared with the conventional method. In this system, the diffracted X-ray data were sampled at a certain time interval with the continuous scanning method and were smoothed by the parabolic approximation of 9 points. After correcting the background, the stress was calculated by the 9 point's parabola fitting method and the half value breadth method.
The results showed no difference between the value obtained by this system and that by conventional method. However, by making use of computer, it was possible to eliminate completely such human mistakes as drawing a chart and reading the diffraction angle from the chart, and to achieve the automatic and high efficient operation on X-ray stress measurement.
