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The paper is devoted to the study of resistance of medium alloy tool steels after laser-plasma cementation. The authors propose a method of increasing abrasive resistance by means of the combined effect of DC electric arc of reverse polarity and laser radiation. The increased concentration of carbon in the near-surface layer is provided by the erosion of the carbon electrode and melting due to the combined energy effect of laser radiation and electric arc. The formation regularities of the diffusion hardened layer are established. The modes of laser-plasma cementation and test results of the studied materials are presented. The reasons of resistance increase are revealed. The mechanical characteristics of the hardened surface layer are shown. The influence of the energy regimes of the technological process on the depth of the diffusion hardened layer is given.

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The possibility of using a two-pulse laser action consisting of a pulse of the free-running pulse followed by the Q-switched pulse in the processes of laser drilling in alumina ceramics is considered. A diagram of a laser machine for implementing the proposed processing method and the method for determining the energy required to form the through hole and the drilling time are presented. For thermal exposure, pulsed radiation of Nd:YAG of the laser operating in the free-running mode (pulse duration 0.5 ms, energy up to 0.3 J) was used. The Q-switched pulse was generated using a second Nd:YAG laser (pulse duration 25–30 ns, energy up to 0.03 J). The laser radiation was focused on the surface of the material at one point. The time between the start of generation of the first and second lasers varied in the range of 0–1000 μs. The optimal delay time for the start of the generation of the second laser relative to the first was determined experimentally. The obtained results showed that the combination of the free-running pulse and the Q-switched pulse can significantly increase the efficiency of laser machining of ceramics and improve the hole quality. This scheme turned out to be promising for optimizing parameters of the process of laser drilling in thin-sheet alumina ceramics. The obtained results obtained have great potential in the field of precision laser machining of ceramics.

Development and implementation of new methods of high-energy surface treatment of structural steels is one of the priorities of modern materials science One of the urgent problems of power engineering is the development of effective processing technologies that allow parts to provide the required properties of working surfaces. The use of laser technologies helps to increase wear resistance, corrosion resistance, reduce the duration of chemical and thermal treatment time and other technological characteristics that can improve the quality, durability and efficiency of parts, increase economic and environmental effects.

The mathematical model for calculation of the coefficient and solidification time of castings in sandy-clay form was developed. It takes into account the basic thermophysical parameters of the casting metal and mold material, heat transfer conditions at the crystallization front, at the ‘casting-mold’ interface and on the mold surface.

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The paper presents the study results of functional coatings of steel 45 formed by Ni, Cr, Mo, W alloying. The mechanical properties and relative resistance of steel 45 after alloying with these elements are presented. It is shown that the alloying coating thickness influence on the thickness of the functional coating. The analysis of the microstructure in the alloying area shows that the mass transfer of alloying components is realized mainly due to the convective motion of the melt. The surface tension of the melt depends on the temperature and the heterogeneity of the free surface heating of the alloying area. It was also found that the degree of hardening, the thickness and the microstructure of laser alloying depends on both the type of alloying component and the properties of the matrix material. The thickness of the alloying area depends not only on the thermophysical characteristics of the system but also on the energy parameters of the laser radiation.