The mechanical properties are obtained by conducting tests on the specimens rather than on the object itself. If the physical object is large and valuable, it cannot be damaged for testing. Non-destructive testing is such a method that does not damage the object.
Non-destructive testing (NDT) is a set of technical means that utilize the characteristics of sound, light, magnetism and electricity, without damaging or affecting the performance of the inspected object, to detect whether there are defects or inhomogeneities in the inspected object, provide information such as the size, location, nature and quantity of the defects, and thereby determine the technical state of the inspected object (such as whether it is qualified or has remaining life, etc.).
The commonly used non-destructive testing methods include radiographic testing, ultrasonic testing, magnetic particle testing and liquid penetrant testing. Other non-destructive testing methods also include eddy current testing, acoustic emission testing, thermal imaging/infrared testing, leakage test, alternating field measurement technology, magnetic flux leakage testing, far-field testing, etc.
Personnel engaged in non-destructive testing need to receive professional training and obtain qualifications before they can hold certificates for work. Different countries, regions and institutions have different requirements for the training qualifications certification of non-destructive testing. Before training, the trainees should be clear about the requirements and choose the appropriate standards and institutions for relevant training and assessment.
