A New Type X-Ray Diffraction Apparatus for Stress Measurement and Its Performance Test Results

Abstract

A new type X-ray diffraction apparatus has been developed to make measurement of stress in machine parts and their structure with ease. It is especially devised to make it practicable to make measurement of samples which show broad or spotty diffraction rings.
The distance of X-rays from the source to the sample surface to the detector of the stress measurement goniometer is shortened as much as possible. A full wave rectification system with smoothing condenser is used as X-ray generator, so that the intensity of diffracted X-rays may be increased from four to five times as much as the old type apparatus. The scanning range of the detector is broadened to 140°∼170°in diffraction angle 2θ. The counting range, time constant, scanning speed of detector and speed of chart feed can be chosen widely according to the intensity and broadening of diffraction lines.
Consequently, the data of broad diffraction lines can be processed easily, and the accuracy of the measurement is improved. The scanning speed of the detector for the measurement of diffraction lines with high X-ray intensity becomes four times as fast as the old type apparatus.
The local stress of the sample with coarse grains can be measured without oscillating the sample, because incidental X-rays can be oscillated around the irradiated point. Without removing the sample, the stress can be measured also by θ-2θ method.
The apparatus is applicable to automatic measurement or automatic digital data processing.