Influence of Chemical Composition of Abrasive Materials and Strength of Interlayer Boundaries on Impact and Abrasive Wear Resistance of Layered Composite Materials

Introduction. Parts of machines and mechanisms that operate in various conditions and come into contact with abrasive particles can quickly wear out and fail. This is especially true for the hydraulic block of a drilling pump, which, due to intense wear, must be replaced after only 5–10 hours of use when pumping heavy drilling fluids. The analysis of scientific literature and experience with drilling pump operation shows that current methods for increasing the wear resistance of structural steels against abrasive and impact-abrasive forces are ineffective. Thus, it is an urgent task to enhance these properties through improved design and manufacturing techniques for drilling pump components, which would reduce the cost of production, repairs, and maintenance. The aim of this work is to study the effect of chemical composition of abrasive particles and the strength of the interlayer boundaries of “wear-resistant steel — rubber” on the impact and abrasive wear resistance of layered composite materials. Materials and Methods. Layered composite materials (LCMs) consisted of: a wear-resistant layer of 40X steel and a rubber layer of BK-1675N butyl rubber. The impact and abrasive wear resistance of the LCMs was studied in accordance with GOST 23.207–79 on a special installation. A mixture of silicon oxide and aluminum was used as an abrasive material. The microstructure of the SCMs surface, as well as the chemical and phase composition of the abrasive particles, were analyzed using equipment from the Common Use Center “Nanotechnology” of Platov SouthRussian State Polytechnic University (NPI). The adhesive strength between the layers of the LCMs was determined using a custom-built installation. Results. The results of the study revealed that the wear resistance of the LCMs was several times higher than that of steels used for manufacturing parts resistant to abrasive particles. During the wear process, solid particles of aluminum and silicon oxides actively embed in the surface of the LCMs, increasing the intensity of wear. In contrast, less solid particles of magnesium and calcium aluminates were destroyed and fixed in formed defects on the LCM surface, slightly reducing wear intensity. It was also found that, when SCM layers were joined by hot vulcanization under pressure with a copper concentration of 25–30% in sintered P40X steel, adhesive strength increased to 0.93 MPa. Discussion and Conclusion. The developed SCMs make it possible not only to increase the abrasive and impactabrasive wear resistance, but also to use cheaper grades of steels as a wear-resistant layer. The proposed method of joining the SCM layers from sintered steels eliminates the need for additional surface machining and the use of special adhesives. Such SCMs can be used in the assemblies of machine parts and mechanisms that are operated in conditions of abrasive and shock-abrasive wear.