Conventional industrial radiography shows inherent contrast limitation where specimens contain low-density internal structures or in the case of very thin objects. An alternative approach to overcome this limitation in absorption radiography is by applying the phase-contrast imaging method. The new and enhanced phase-contrast imaging method, using micro-focus X-ray tubes, is discussed in this presentation. The micro-focus X-ray tubes, having focal-spot sizes in the range of micro-meters, has been developed as a powerful tool for quality control in different industries. The key element to this technique is the high spatial resolution of X-ray beam, emitted by micro-focus tubes as opposed to the conventional radiographic system. In phase-contrast imaging, one can record the variation of the phase of the passing X-ray beams in order to enhance the obtained image for parts with low absorbent materials. Research on phase contrast imaging has been previously done on biological tissues for medical research purposes. The technique can be successfully applied to low absorbent samples in industrial set up, thereby demonstrating significant enhancement. Optimization of the experimental set up and radiographic parameters to achieve phase-contrast images are described in this presentation. The phase-contrast X-ray imaging provides enhanced image contrast, and improved edge definition, essential in further development of nondestructive evaluation for low-density materials.

Related Publications