This paper provides deeper insights into the performance of diamond particulate reinforced refractory composites used for cutting tools in the oil and gas industries. In particular, 25C_diamond–70.5WC–4.5Co composites were enhanced with zirconia additives in proportions of 4 wt.% and 10 wt.% via the spark plasma sintering method. Wear tests were performed, and the analyses of elemental composition, morphology, and microstructure were completed. It was found that the addition of yttria-stabilized zirconia increased the plasticity of the matrix and thus introduced the ductile fracture mechanism, reducing the role of abrasive wear. As a result, the specific wear rate was reduced by 44% after the addition of 4 wt.% of zirconia and by 80% with 10 wt.% of ZrO₂. The presence of zirconia contributed to the increase in the retention force between the matrix and diamond grits, which further reduced the intensity of the abrasive mechanism.

This paper studies composite diamond-containing materials (CDM) based on carbide matrices containing tungsten carbide (WC), cobalt (Co) micropowders and CrB2 micropowder additives in small quantities. These materials are intended for creating tools aimed at efficient destruction of hard rocks, which is important for various geological and mining operations. The main objective of the study is to develop and create CDM with improved mechanical and operational characteristics, such as hardness, crack resistance, compressive and bending strength, as well as wear resistance and productivity. These characteristics are necessary to increase the efficiency of rock-destroying tools. Micromechanical methods using a Nano Indenter G200 nanohardness tester and a FALCON 500 microhardness tester were used to conduct evaluation tests. The experiments showed that adding 4% CrB2 significantly increases the fracture toughness of the material and improves the matrix microstructure, which in turn leads to an increase in mechanical properties. The results obtained are important for creating more efficient and durable tools for drilling oil and gas wells. The economic significance of the work lies in increasing the productivity of drilling in hard rocks, which helps to accelerate the commissioning of new fields. It is also expected that in the future a number of new types of drill bits will be developed that will use high-quality diamond raw materials, which will further improve the efficiency of mining and drilling operations.

In this paper, the use of rubber-polymer composites ELTC (End of Life Tire Compound) for modification of BND 70/100 bitumen was investigated. ELTC contains not only devulcanized rubber from used automobile tires, but also used plastics (polymers), such as polyethylene (PE) and polypropylene (PP). ELTC was obtained by applying the method of rubber devulcanization using a selective catalyst, which allows selective decomposition of sulfide bonds at relatively low temperatures, while preserving most of the macromolecular chains. The characteristics of the asphalt binder were improved after modification by ELTC. After modification, the base asphalt binder became more uniform, and the thermal stability of the base asphalt binder increased. ELTC is uniformly distributed, the compatibility between the components of the modified asphalt binder is good, which proves the homogeneity of the modified asphalt binders. The results show that all ELTC formulations improve their softening point and increase their resistance to plastic deformation in summer. The results of the needle penetration test at 25°C show that the addition of modifiers reduces the penetration value. This means that at this test temperature, the modified bitumen becomes harder compared to the unmodified bitumen.

In the process of drilling oil and gas wells, the selection and design of drilling fluids play a key role in ensuring the stability and safety of the drilling process. Drilling fluids should ensure wellbore stability, effective cuttings removal and prevention of various complications, such as collapses, mud absorption, gas, oil and water shows and other geotechnical problems. The article dis-cusses in detail the basic principles of selecting drilling fluids, as well as their composition and physicochemical properties, which can vary depending on geological conditions, such as porosity and permeability of rocks, pressure and temperature in the drilling zone. Particular attention is paid to regulating the density of the solution, which is important for preventing destruction and maintaining borehole stability. Also discussed are wellbore flushing methods that allow for effective cleaning of the walls from cuttings, increasing productivity and reducing the risk of contamination. The article also analyzes various ways to prevent complications, such as absorption of the solution in porous rocks, which can significantly increase drilling costs. Examples are given of the use of special additives and modifiers that help improve the properties of the solution, increasing its stability and preventing problems associated with reactions with rocks. Special attention is paid to modern modifications of drilling fluids that have improved properties and function effectively under high temperatures and pressures typical of complex geological situations. Prospects for their future use and possible innovations in this area are considered, which opens up new opportunities for improving the safety and cost-effectiveness of drilling operations.