The influence of the particle velocity on the formation intermetallic of coatings is discussed. The primary phases of detonation sprayed NiAl coatings are NiAl and Ni 3 Al, and also a solid solution of Ni in NiAl. The lamellar and homogeneous distribution of Al may be due to the oxidation of the powder particles during their flight in the pulsating high temperature, high velocity jet of the gas detonation process. During heating and melting of the powder particles, an aluminum oxide film is formed. This film takes part in the coating formation and affects the Al distribution. Another important observation is the presence of NiAl and Ni3Al phases in the coating structure. The transition zone between the coating and substrate has a thickness of 10-15 µm. The character of the distribution curves of Al and Ni confirms the lamellar distribution of NiAl and Ni 3 Al phases in the coating.

The principles of system approach to modeling of sprayed particles interaction with substrate in process of thermal spraying of coatings are discussed. The proposed model have six levels for analysis of particle-substrate interaction system: functional, technological, mechanical interaction, thermal, mass transfer level, and metallophysics level.

The short description of traditional methods of thermal sprayed coatings (TSC) structure characterization is given. The main parameters of structure and physico-mechanical properties of TSC, which influenced on their wear resistance are considered. The system approach for analyses of structure of TSC and the scheme of TSC properties prediction is proposed. The classification of structure levels of wear resistant coatings, obtained by thermal spraying, and models of their elements are proposed. The advisability of use of methods of structure-simulation modeling of TSC is shown.