ДОСЛІДЖЕННЯ ЗНОСОСТІЙКОСТІ КОМПОЗИЦІЙНИХ ПОКРИТТІВ, ОТРИМАНИХ ХОЛОДНИМ ГАЗОДИНАМІЧНИМ НАПИЛЮВАННЯМ, В УМОВАХ ДІЇ ВІЛЬНИМ АБРАЗИВОМ

<jats:p>The object of the study is the regularities of abrasive wear in composite coatings produced by cold gas dynamic spraying (CGDS). The aim of the work is to increase the wear resistance of titanium alloy parts under loose abrasive conditions by applying CGDS composite coatings based on the Ni-Al₂O₃ system, incorporating carbide powders. To achieve this aim, the following tasks were solved: 1) nickel-based coatings with the addition of tungsten carbide (WC), boron carbide (B₄C), and silicon carbide (SiC) powders were deposited on VT9 titanium alloy samples using CGDS; 2) the wear regularities of the prepared coated specimens were investigated under loose abrasive conditions, determining mass loss and thickness changes, and comparing them with data for uncoated specimens. Methods used: coating formation was carried out by the CGDS method using a DYMET-405 system. A nickel-based powder mixture with the addition of aluminum oxide was selected for coating deposition, into which tungsten, boron carbide, and silicon carbide powders were added. Coating deposition was performed on specimens prepared from VT9 titanium alloy. Tribological testing was conducted in accordance with the ASTM G65 standard on a specialized test rig simulating friction conditions against a non-rigidly fixed abrasive. Quartz sand with a grain size of 250–500 μm and a rubber wheel with a hardness of 60 Shore A were used for the analysis. The wear resistance of the coatings was evaluated by measuring the mass loss of the specimens on laboratory balances with an accuracy of 0.001 g. Conclusions. It was established that applying composite coatings significantly increases the wear resistance of VT9 titanium alloy surfaces. The addition of 30% carbide powder (WC, B₄C, SiC) to the Ni-Al₂O₃ powder mixture ensures a 25.0% reduction in mass loss compared to coatings without carbide reinforcement and a 71.2% reduction compared to uncoated VT9 alloy specimens. The scientific novelty lies in establishing the regularities of abrasive wear of carbide-reinforced Ni-Al₂O₃ system composite coatings obtained by cold gas dynamic spraying under the action of a loose abrasive.</jats:p>