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The use of chromium carbides in flux-cored wire for applying abrasion-resistant coatings is considered. It is found that such use of chromium carbides does not result in reinforcement of the resulting coatings by intact carbide particles. However, the replacement of ferrochrome by chromium carbides changes the structure of the wire and coatings, with increase in the hardness.

The use of chromium carbides to harden surfaced metal that is subject to abrasive wear is considered. With correct hardening of the applied layer, carbide formation extends the working life.

The paper presents the results of research on the influence of the conditions of volume electric arc surfacing on the geometric accuracy of “cube” type objects with dimensions of 20 × 20 × 20 mm made of 09Mn2Si and 06Cr19Ni9Ti steel fillers. It has been found that the actual length and width dimensions of the samples surfaced with 09Mn2Si steel generally are exceeded and the dimensions in height are smaller than the specified dimensions of the model. This may be due to the melt spreading over the substrate during the formation of the first layers. The optimal surfacing conditions for cube type objects made of 09Mn2Si steel have been defined. When surfacing the samples of 06Cr19Ni9Ti steel, spreading does not occur; however, all actual dimensions are smaller than the specified ones. This might be caused by shrinkage processes that proceed in the deposited layers during their solidification. The most optimal mode for samples made of 06Cr19Ni9Ti steel is the mode in which the reduction in length and width was no more than 2.5%, and that in height was 13.5%. Studies on the influence of the welding arc voltage and the grade of the filler material on the width of the deposited track has confirmed the tendency of 09Mn2Si steel to spread over the substrate in the entire voltage range studied (11–19 V). The microstructure of the deposited samples has been investigated. Tensile tests of the deposited samples at room temperature have shown that the samples have a set of acceptable mechanical properties that exceed the reference values. This is a proof that the deposition process occurs at a high level of quality without formation of incomplete fusion and porosity areas.

A method was proposed for optimizing the process of oil shale pyrolysis with the addition of a cleaning unit. With the use of this method, the degree of removal of H2S and CO2 from pyrolysis gas was almost 100%, which makes it possible to use the resulting gas as fuel.