Abstract
The mottled appearance frequently observed in radiograph of austenitic stainless steel weldments and castings has been investigated. The results may be summarized as follows.
1. It has been established that the X-ray diffraction causes the mottling. Diffraction theory (Bragg's law), however, does not explain the whole phenmena. 2. The relation between the incident beam angle and the mottling was obtained. 3. It was observed that the mottling was more pronounced on radiograph taken with a low voltage than on one taken with high voltage. 4. Solution treatment does not affect the mottling. 5. The mottling disappeared when the specimen was recrystallized.
