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The features of the integrated diagnostics of the discs of gas turbines of gas-compressor units using eddy-current and dye-penetrant testing are considered. The effectiveness of the detection of the crack-type defects in HPT and LPT discs under the first tooth of the fir-tree slots of the discs along the contact line of the teeth of the comb and blade butt are demonstrated. The calculations of the stress–strain state allowed the estimation of the occurrence of cracks in the fir-tree slots of discs, as well as the service life of discs up to crack formation at extraordinary operating temperatures. Integrated quality control by eddy-current and color capillary nondestructive testing provides reliable crack detection in details without serious costs for mechanical preparation of items for inspection along with a substantial reduction of the labor-intensiveness and depth of the inspection.

The lifecycle of modern industrial gas turbines can reach hundred thousand hours and usually the turbine blades need to be replaced. The use of super alloys and application of advanced coatings makes the cost of turbine lifecycle rather high. The methods for blade rejuvenation and life extension are based on the analysis of the main defects which can considerably reduce blade strength. The effect of long operation and typical defects in turbine blades has been studied in correlation with HCF. The decrease of blades HCF under the effect of operation has been considered as the result of influence of mechanical and thermal factors. The influence of FOD on the blade HCF strength is studied. Some random defects in turbine blades which resulted in HCF decreasing and blade failure are considered. The rejuvenation heat treatment for the blades of ZhS6K and EI893 and its positive effect on metal properties is demonstrated. The ultrasonic shot peening for operated blades have been considered. It is demonstrated that HCF strength of blades after shot peening is about 25–30% higher. Relaxation of compressing stresses in operation is shown as not essential. The remaining life of operated blades can be estimated using the correlation of endurance limit and run time.

We propose using the method of holographic microscopy to detect fine morphologic changes in living cells. An “LSM 510” laser confocal scanning microscope is modified to allow recording digital microholograms which can be used to reconstruct the amplitude and phase of the radiation transmitting through the sample. Measuring the phase increment of the object beam in cells and the intercellular space yields information on the optical length of the ray path in the cells (spatial dimensions and the refractive index), which in turn contains information on changes in the morphology and intracellular contents. Calcium activity is studied by means of fluorescent microscopy which makes it possible to detect minor variations in the intracellular concentration of calcium ions. By studying the dynamics of calcium oscillations and variations in the optical thickness, conclusions are made about the interrelation of functional and morphological variations, and comparative analysis of these variations is performed.

We present the concept of combining the holographic and localization fluorescent microscopy. The ways to optimize the optical schemes and image recording regimes in the process of combining such interferometric and statistical methods are developed, which makes it possible to study the dynamics of the internal cell structure with transverse and longitudinal superresolution.

The article presents the results of the analysis of operation of working blades made of cast nickel alloys applied in gas turbines for power. Russian alloys having equiaxial crystallization, i.e., TsNK-7, ChS-104, ZMI-3U, ChS-70U, ChS-88U, ZhS6K, and one foreign alloy IN738LC (for comparison) are considered.

Results from thermocyclic tests of nickel- and cobalt-based alloys used to manufacture blades for modern gas turbines are presented.

Results from studies on analyzing the state of materials and protective coatings of gas turbine blade systems subjected to the sulfide-oxide corrosion are presented, and factors causing its occurrence are described. Data obtained from studies on analyzing the effect of doping on the resistance of nickel alloys to corrosion are given, as well as data obtained from studies of the corrosion longevity of thermo barrier coatings.

We present the results obtained from a comprehensive study of the plasma metalloceramic coating applied on the external surfaces and diffusion coating applied on the internal surfaces of rotor blades and guide vanes used in stages 1–3 of a GTE-65 gas turbine unit.

Specific features of thermal fatigue fracture of a monocrystalline alloy used in manufacturing of rotor blades of gas-turbine units are investigated. The dependences of the number of cycles to failure on the crystallographic orientation of the material, maximum temperature in a cycle, temperature range, and stress concentration are established. The effects of the pores and processes of recrystallization on the degree of thermal fatigue damage are analyzed.

Apparatus has been developed and assembled to obtain holograms of a living cell culture by methods of digital and analog holography. The setup demonstrates the advantages of both methods and provides convenient adjustment and monitoring of its parameters for recording a series of digital holograms. Software processing of the results makes it possible to obtain information concerning the total optical thickness of the test samples and to visualize and measure changes in living neuronal cultures. Variations of the structure and manifestations of vital activity of a primary culture of brain cells have been investigated and compared.