Sophisticated Microwave Nondestructive Testing Method for Metals

Abstract

The present paper describes theoretically and experimentally the possibility of such electron gas interaction with low-frequency ultrasonic waves, which the authors determine as a newly revealed phenomenon or even discovery, changing the physical concept of metal destruction processes and metal ageing. In contrast to previous experiments in determining surface cracks by MW method, the author has produced new experimental data in identifying invisible metal defects, i.e. active defects. Although the described method is based on the well-known Acoustic Emission (AE) method, there are significant differences. Firstly, according to calculations and experiment results the propagation speed of active defects generated by this new method is close to the speed of light. Secondly, in contrast to single AE events, occurring under conditions of excessive mechanical force, displayed signals in this new method can be detected during a time-interval excluding an additional mechanical load. Finally, the non-contact detection of dangerous defects, i.e. active defects, indicates the advantageous aspect of this new method to the contact AE method. This paper presents experimental data, sustaining the possible practical application of an advanced remote indicator of active defects (RIAD) as a diagnostic technique for steam railway car wheels in motion mode, testing reliability parameters of rotating turbine blades and operating sucker rod pumps.

The Usage of the Microwave Crack Detector for Fatigue Cracks Detection

“…The previous tests on the laboratory models of the microwave sensors used for the detection of the active defects in the metal samples allowed to begin the research, being of concern to the remote detection of the active defects. The earlier tests, performed on the tension testing machines showed the range of the microwave sensor capability by its fatigue failure load (see Gorbunov & Sutorikhin, 1999, 2010, 2012. The new tests results showed the possibility of determining the danger rating in the increasing fatigue stress.…”

Nonreciprocal backscattering of millimeter waves by lithium niobate crystals when ultrasonic vibrations are excited in them

“…, Um HY 2 (t), we obtain an estimate of the spectral characteristics of the backscattering matrix S ps, in which the Doppler frequencies are the most important. The method of the experimental study of backscattering for solving similar problems was developed earlier [14][15][16][17]. In the present paper to study the backscattering of crystals of microwaves at a frequency of 33 GHz under the action of ultrasound, we used unit, the scheme of which is shown in Fig.…”