The article presents a method of developing a mathematical model of the arc surfacing process performed using the self-shielded flux-cored filler metal wire with the chromium cast iron (Fe15) weld deposit. A three-level design (static, determined, and complete) was used to determine the function of the test object, thus enabling the simulation of deposition rate in relation to wire feed speed and electrode extension. The deposition rate for the specified set of surfacing parameters amounted to between 4.31 kg/h and 11.25 kg/h. The study was also concerned with identifying the effect of the significance level of test factors and interactions between them on the resultant factor, as well as an assessment of the adequacy of the test object function. In relation to significance level α = 0.01, regression coefficients b₀, b₁, b₂, and b₁₁ significantly affected the deposition rate of the surfacing process. Coefficient b₂₂ was significant at a level of 0.40, whereas coefficient b₁₂ was significant at a level of 0.15. The mathematical model presenting the effect of wire feed speed and electrode extension, as well as interactions between them on the deposition rate of the surfacing process, was adequate for the adopted level of significance α = 0.05.

Tribological tests in real conditions enable obtaining full data on the life of interacting machine parts. This article presents the results of operational tests on the elements of the support ring guidance system in a vertical ball-race mill. The guide and active armour operate under abrasive wear conditions with moderate-impact loads. The wear resistance of elements with overlay welding layers deposited with flux cored wire with a structure of high-alloy chrome cast iron and with a coating flame-sprayed with nickel-based powder was compared. The wear intensity of the overlay weld deposits was much lower than that of the sprayed coatings. The scope of this study also included the analysis of the chemical and phase composition, macro- and microscopic metallographic examinations, and the measurement of the hardness of the deposited layers and coatings.

Composite layers consisting of a metal matrix reinforced with tungsten carbide particles provide very high resistance to abrasive wear. However, tungsten carbide particles are exposed to the intense effect of the heat source during surfacing, which leads to their degradation and non-uniform distribution in the overlay weld, while the deposition rate is low and the cost of the process is high. Existing articles cover only selected processes and do not address commercial filler materials or the effect of multiple process conditions on the tungsten carbide content in the overlay weld. The article presents a review of industrially used technologies for the deposition of composite layers with tungsten carbide, including oxyfuel gas surfacing, manual metal arc surfacing, flux-cored arc surfacing, tungsten inert-gas surfacing, plasma surfacing, and laser surfacing. This review includes a description of the properties of the available filler materials, the effect of deposition process conditions on the content of tungsten carbide particles in the overlay weld, and potential directions for the development of technologies for depositing composite layers. The article is based on available literature data, information materials provided by manufacturers of filler materials, and the authors’ industrial experience.