X-ray Nondestructive Testing as an Essential Tool during Technology Design and Development of Modern Aircraft Materials

摘要

The X-ray nondestructive testing process is carried out by a system which includes an object of control (OC), source of radiation, detector, and operator. Under interaction of radiation with the OC, its radiation image is formed as an X-ray dose distribution in accordance with the OC properties. At this stage, useful information about the OC is formed, which is further partially lost, partially distorted, and veiled with a noise by conversion of a radiation image into an optical one. The optical image is analyzed by an operator, and the result of testing depends on his physical and emotional state. In this article, the step-by-step analysis of the entire radiation monitoring system is performed. The first stage is formation of a radiation image. For the theoretical estimate of the minimum defect size detected by the X-ray testing system, spatial-frequency spectrum analysis was used. The minimum sizes of a defect were established, for which the radiation image will be formed depending on the characteristics of the source of radiation and the OC. The second stage is the transformation of the radiation image into an optical one. We presented the simulation of this process and developed a model of how an operator recognizes the X-ray optical image and makes the decision about the OC condition. The optical image formation was studied and the choice criterion for the radiation energy was determined by using the digital radiography technique.