Due to the technological revolution, in order to withstand competition, giant production companies are obliged to provide customers with the most reliable and safe products in the shortest possible time while keeping the price of the product affordable to customers as well. To achieve this goal, the companies must undertake several complicated tasks, such as making complex dimensional measurements, detecting the defects, and repairing them before bringing the product to market. At that point the non-destructive testing (NDT) comes into play which is a very broad concept containing myriad of conventional and also state-of-the-art methodologies. In this paper, several techniques for NDT, such as X-ray imaging, acoustic emission, ultrasonic testing, infrared thermography, digital image correlation, terahertz testing, shearography will be investigated. Moreover, the principles, advantages and disadvantages and application areas of these techniques will be introduced, and specific examples will be described for some of the methods.

The 4th Industrial Revolution (4IR) is developing, leading the transition to the post-industrial era. Both the industry and the business world as well as the civil society, have already realized that the world as it exists is about to change due to the 4th Industrial Revolution. Many countries and stakeholders, realizing (4IR)’s importance, have already incorporated it into official policies while the companies at the forefront are called upon to integrate a variety of new technologies. Among other technologies, in this context, the evolution of non-destructive testing is of significant importance, having a positive impact not only on productivity but also on numerous technical, managerial, and economical aspects of the final product. The present work attempts to highlight this issue and form the basis for relevant future research.