Some practical NDE and QC Applications of Time Domain Terahertz Technology

This is an introductory talk, which will briefly discuss the principles of the generation and measurement of terahertz energy, look at its interaction with different materials and show how these principles can be employed to perform inspections of a wide variety of nonconductive materials, including single or multi-layer plastic structures and coatings on both conductive and nonconductive substrates. Terahertz technology, using electromagnetic waves situated between microwaves and the far infra-red, is another ‘tool in the box’ enabling accurate measurement of layer thickness, location of metallic inserts, and detection of discontinuities in materials and configurations that are unsuited for ‘conventional’ inspection approaches. Terahertz investigations are non-harmful, non-contact and normally can be applied from one side of a part. This talk will discuss the applicability of this technology to several practical applications in the aerospace, manufacturing, energy, construction and oil and gas industries. This includes applications where the technology has been implemented into production, and others where it has been investigated, shown to be feasible, but not yet implemented due to external factors. We will also mention its application in several ‘cultural heritage’ investigations. Brief details of equipment used will be discussed and an outline case study showing development of a technique and the accuracy which can be obtained will be presented.