Plasma coatings containing high-baring phases

Abstract

Results of comparative researches of the initial and processed in a plasma flow oxidic microcomposites, consisting of TiO2, SiO2, Al2O3, ZrO2, and plasma coverings from them – the materials which are characterized by amorphous and crystal structure and strengthened by ultradispersed phases of the stishovit, are presented. It is shown the influence of a type, structure and a way of processing of material (initial powder of different dispersion; the powder obtained in a plasma flow at the different modes and with the normal and accelerated cooling; a plasma layered composite) on the content of silicon oxides, aluminum and titanium, on the type of polymorphic transformations (anatase is found both in powders, and in coverings; the accelerated cooling of spheroids leads to growth of its contents in microcomposites) and also on feature of forming in ceramic materials of a high-bar phase – the stishovit (stishovit it is found only in coverings). It is established that increase in power of the plasma generator leads to increase in extent of amorphicity of plasma-layered composites. In the structure of layered composites three groups of the inclusions, combined by the composition, are revealed: two groups of aluminosilicates and inclusions on the basis of zirconium dioxide. Inclusions of the third group are characterized by two types of structures: homogeneous, consisting of zircon, and plated (with a kernel of dioxide of zirconium and a cover from zircon). The developed layered composites are characterized by high wear resistance, corrosion resistance and antifriction properties. In the conditions of low-temperature plasma at atmospheric pressure the stishovit-containing materials are obtained for the first time.