Wear detonation amorphously- crystalline coverages at ladening friction

Abstract

Presents the results of experimental researches of wear and character of it dependence from slip speed at the testing of coverage’s in non-lubricated. Established that the amorphous-crystalline composition having high mechanical properties, characterized by considerable resistance to wear, which does not concede to those values wolfram containing hard alloys type BK15, and is the perspective competitive material for the creation of tribo-resistant coatings. Investigated the changes in mechanical properties of the coatings, depending on the quantitative composition of the components, defined by their optimum content. Studied the distribution of elements through the thickness of of the sprayed layer. The resulting differences in the chemical composition, confirm the presence of disbalance dispersion structure, which coincides with modern ideas about the nature of amorphous and amorphous-crystalline composites, number of amorphous phase in the coating is up to 82 %. Except the amorphous phase in the coating phase includes localized in some areas of the amorphous matrix, characterized by microcrystalline structure. On roentgenograms are installed on some lines corresponding to the lattice of α-Zr, moreover, in an amorphous matrix boron-rich zones are distinguishable, which are ultra thin type inclusion phases ZrB2, AlB2. Defined the presence of such nano-phase intermetallic structures as Zr2Al, coherently related to the matrix. Considered electron-diffraction of surface coatings received in original condition and under loading friction. Found that the formation of an amorphous structure with increasing the sliding speed, caused by gradual dissolution of local microcrystalline inclusions and full microdiffraction model forms only amorphous matrix. In the process of friction amorphous layer reduces the adhesion component of friction power, while its plastic deformation, is not associated with significant thermal costs and promotes a minimum of energy loss. Metallographic analysis and strip chart recording friction surfaces indicate the absence of visible damage of the surface layers and confirm that the leading type of wear in the whole range of tests is mechanochemical.