MODERN PHYSICAL METHODS FOR INVESTIGATING MATERIALS
Different physical methods of testing and investigating the physical and mechanical properties of materials are studied. The analysis of traditional methods based on a variety of physical phenomena is carried out. As a result, the existing methods are improved, and new methods for testing materials by using the latest achievements in physics and material science are developed. The essence of the above- mentioned methods, the structure and operating principle of the used instruments, in particular, the styloscope and stylometer schemes in the methods of structural and spectral analyses are described. The essence of pyrometers with differential thermocouples in the thermal analysis method; the device for radiographic analysis; the magnetic flow detector with induction actions in the ponderomotive method with magnetic analysis for establishing the presence of internal defects in details; the ultrasonic flow detector, as well as the scheme of ultrasonic pulse reflective flow detector; the structure and principle of operation of an inductive tensometer for measuring deformations in tensometry are also considered. The essence of the polarization-optical method of investigation, the advanced method of electrical modeling, the method of X-ray flow detection, in particular the X-ray interferometric method of image interpretation of defects, the method of double three- and four-crystal interferometers, triple three- and four-crystal interferometers are described. It is shown that interferometric topographic patterns depend on the orientation of the reflecting planes, the unambiguous interpretation of the image of the defects is greatly facilitated when interferograms are obtained with the help of multiple interferometers, and multiple interferometers give a more complete description of the deformed state of the crystals. It has been experimentally proved that interferometric patterns obtained from the same crystal with the help of families of symmetrically equivalent planes will be the same only in the case when the crystals of the interferometer are ideal. It is shown that in a four-block interferometer pairwise imposition of diffracted beams leads to three different moire bands in contrast, and when three beams are imposed, the contrast of moiré patterns is greatly reduced.