Non-destructive evaluation of material quality (Part 1)

Non-destructive testing (NDT) methods were initially developed in the 1960s to meet the needs of cutting-edge sectors where safety was paramount, but their use has since spread to the entire industrial world. They are now part of the standard tools used to improve productivity and guarantee product compliance with stringent customer quality requirements, thus contributing to ultimate customer satisfaction. In parallel with this evolution, non-destructive testing has broadened its scope of application, moving from the strict domain of detection, recognition and sizing of localized defects to that of assessing the intrinsic characteristics of materials, thus becoming a key player in product quality assessment.

Starting from the physical principles underlying the main non-destructive testing methods – radiography, ultrasound, electromagnetic eddy current, Barkhausen noise and incremental permeability techniques, surface examination techniques for leakage flow processes, dye penetrant testing and optical inspection – this text seeks to show how these methods provide solutions – often at a stage of industrial maturity – to this dual problem.

Radiography and ultrasound are the subject of this first article.