The origin of modern non-destructive testing (NDT) can be traced back to more than 100 years ago. With the discovery of X-ray by German physicist Conrad Roentgen in 1895, people began to realize that X-ray detection may be used in the field of medicine as early as in the 1920s.
It is said that the ancient Romans used flour and grease to examine for cracks in marble, while centuries later, when the blacksmiths hammered metal into shapes, they distinguished different metal rings according to their sound waves. However, Saxby was the first one to apply NDT to actual production in 1868 in England, and he used the magnetism of a compass needle to detect cracks in a gun barrel.
NDT has been proved to be indispensable for large-scale industrial production in World War II and a period after World War II. At that time, NDT device was mainly used to detect whether products were qualified. With the end of the war and the development of NDT technology, it not only reduced the rate of defective products, but also gradually highlighted its economic benefits. After that, NDT application is directly related to the safety of industrial production, the development of new materials and the requirements of higher product reliability.
Today, ECT NDT is widely used in the aerospace industry. Although destructive testing is the simplest way to detect the structure and performance of a component, it is obviously not applicable to all cases. For some large and low-cost components, it may be possible to sacrifice some of them for destructive testing to obtain test results, but for small and high-cost components used in the aerospace industry, this is not a viable option. According to the Foreign NDT Association, NDT has become a compulsory course for many aerospace companies due to its irreplaceable role in the growth process.