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The effect of the structural transformations during non-vacuum electron-beam cladding of amorphous boron powder on the hydroabrasive wear resistance of the surface layers of a chromium-nickel austenitic steel is studied. It is shown that the cladding yields a coating with densely arranged borides. An x-ray method is used to show that the modified layer consists virtually fully of Fe2 B iron borides. This structure raises the hydroabrasive strength of steel 12Kh18N9T by a factor of 1.5 – 2.

The wear of steel plates under the impact of a hydroabrasive jet was studied experimentally by varying the distance between the sample surface and the nozzle, the angle of impingement of the jet on the plate, and the abrasive concentrations in water and in the ambient medium (jet in air, submerged jet). The results are compared with available data on the structure of the jet and jet flow around an obstacle. It is shown that the addition of abrasive particles to the liquid can be used to study the liquid jet flow around an obstacle because the form of surface wear allows one to determine the region of impact of the jet core, the deceleration region, and the near-wall flow region before flow separation.

Characterization of coatings made with the help of Computer Controlled Detonation Spraying (CCDS) was performed. The applied coatings include hard alloys (WC/Co -75/25, WC/Co - 88/12, WC/Co/Cr - 86/10/4, and Cr2C3 / NiCr), aluminum oxide, nickel-chromium self-fluxing alloy, titanium, bronze, and stainless steel. Tribological investigations of coatings were provided using abrasion test (ASTM standard G65), erosion test (ASTM standard G76), and hydro-abrasive test. To make hydro-abrasive tests special device and method were elaborated based on the interaction of water jet saturated with corundum particles with a coating surface.