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The possibility of applying the method of ultrajet diagnostics for estimation of the stress–strain state (SSS) of carbon-fiber samples is considered. It was shown as a result of a series of experiments and numeric computations that informative parameters of the cavern do not contain objective information about the state of material in the current load state. This may be useful for the construction of a general method for diagnosing samples made of carbon fiber for estimation of their operational life, including the conditions of the effect of a set of external factors: static loading, temperature, various types of electromagnetic radiation, et al. Experiments showed there to be high indicators of correlation between computed values of stresses and depths of caverns formed as a result of ultrajet impact on the surface of carbon-fiber samples.

The problem of increasing of the strength of concretes by means of using suspension based on nanomodified additives with boehmite, graphene and carbon nanotubes is considered. Suspensions were primarily subjected to ultrajet processing. Nano-containing suspensions were studied before and after processing by the indicated method using a Microtrac Bluewave laser analyzer of particle sizes. The analysis provided average particle sizes by quantitative and volume distribution, as well as minimal registered size of particles in the samples. The results of compression strength tests of a batch of concrete samples are presented. It was shown that the use of nanomodified additives leads to an increase in the strength of concrete. It was concluded that investigations must be continued in order to obtain a larger amount of experimental data for statistical processing.

A new technique for examining composites by means if ultrajet diagnostics is considered. The scientific approach is based on imitating material fatigue tests in accelerated mode and evaluating composites for adhesive strength at alternate loads. Ultrajet diagnostics will allow ensuring the performance adequacy of resource strength calculations while designing items from composites by rapidly determining the necessary parameters of physical mechanical properties in the course of their design and process development. A Ti6Al4V titanium alloy powder sample made by selective laser melting is used as an example to show that the geometric parameters of hydroerosion are associated with the surface defects of the sample, its stress–strain state and the in-growth path and direction followed by the scanning laser beam.

A method for the ultrajet diagnostics of products made of composite materials is presented. It makes it possible to simulate, in an accelerated regime, the fatigue tests of materials and to estimate the adhesion strength of the fiber-filler bond under alternating loads. A hydroerosion model of the diagnosed surface under the operation of sequentially conjugate ultrajet actions by various working hydraulic pressures of the ultrajet water applied is considered. The concentration of the functionally significant defects formed at a certain stage in the life cycle of the object of analysis, for example, in the surface layer of the diagnosed product, is taken as a general characteristic of the hydroerosion of the material. Relations that determine the kinetics of formation of an ultrajet hydrocavity on the surface of the object of analysis are obtained. The time spent by the ultrasound on the erosion destruction of the softened layer is determined, which is a new information-diagnostics criterion, since this time characterizes the correlation between the level of action on the surface layer of material and its physical and technological reaction to the ultrajet effect. Results of this research will help one not only to clarify the fracture laws of composites under unsteady loadings, but will also ensure the creation of composite materials with predetermined physical, mechanical, and chemical properties for specific application conditions.