The basic information about physical, metallurgical and technological causes of defects of the metal materials and alloys, especially unalloyed steel, low alloy and high alloy steels, grey and white cast iron. Is given the basic information about the classification systems of the defects. The example of the classification systems of cast metals, wrought metals and welded metals - namely steels. The defects of cast and wrought steel and the defects of welded steels are explained in detail. It means that is given: - the possibilities of identification of the defect, - its technological causes, - and the possibilities of its prevention. Than are explained the following problems:
- The significance and basic principles of the statistical control of defects in the factory.
- The diagnostic of the defects by means of non-destructive method of testing.
- The problems of non-destructive testing of semi-product and final-product from different metal materials and alloy in the industry.
- The problems and main principles of quality inspection.
- The principles and using of capillary method, electrical and magnetically methods, X-ray methods, ultrasonic methods.
- And the problem: How to use the statistical and analytical methods of the identification of defects to their prevention?