ity of the parts, the serviceability of which depends mainly on the quality of their surface layer. The impeller has the highest load of any element in the flow section of a centrifugal compressor. When the impeller rotates at high speed (the circumferential velocities reach 300 m/sec), the centrifugal forces in the impeller material cause high internal stresses. Moreover, the impeller is subjected to the action of pressure, temperature, and a corrosive working medium. Carbon steels are used for impellers if a noncorrosive gas is the working medium and alloy and chromium–nickel steels (30KhGS, Kh15NYuA, 07Kh16N6, etc.) are used for work with corrosive working media. Impellers can be divided into three technological groups [1]: • open design: all the elements of the impeller (main disk, covering disk, and blades) and are then put together by riveting, welding, or brazing; impeller is assembled. • half-open design: entirely milled (blade) and covering disks are made and then put together by riveting, welding, or brazing; impeller is assembled. • closed design: monolithic impeller; made by casting, milling, electroerosion machining. The manufacture of impellers in the various groups differs as to technological processes, equipment used, and appliances. Such a classification makes it possible, despite the diversity of impellers, to develop typical technological processes for strengthening them and thus speed up their manufacture. The complexity and high cost of producing centrifugal compressor impellers lead to exacting wear resistance requirements. In most cases, impellers fail because of erosion wear of their blades, which substantially affects the aerodynamic properties of the blade leading edge. After operation for some time under conditions with a flow containing dust, any initial profile of the leading edge becomes sharper. The convex (working) surfaces of the blades often display considerable pitting that is further from the inlet around the main disk than it is across the width of the remainder of the blade. Such pitting forms in the region of the outlet part near the main disk [2]. Sometimes the blade is pierced at those places. Table 1 gives the most characteristic causes of the failure of compressor impellers and ways of eliminating those causes. The service life of centrifugal compressor impellers and other parts subjected to abrasive wear is increased by applying wear-resistant coatings [3, 4]. In one wear-resistant coating, the VK6 hard alloy mixture is the filler and a solid solution of the Ni–Cr–Si–B system is the low-melting binder. The coating is applied on the surface of the parts by the glazChemical and Petroleum Engineering, Vol. 39, Nos. 1–2, 2003