The technology of producing a composite material based on a multifunctional oxide ceramics

The synthesis of composite SHS powders with components of solid lubricant is described. The powders of the following composition: Al 2O 3 + 30% TiO 2 + 12.5% MoS 2; Al 2O 3 + 30% TiO 2 + 12.5% CaF 2 were investigated. The synthesis of compositions was carried out in a reactor using self-propagation mode without supply of energy from an external source in a nitrogen-oxygen atmosphere with an oxygen content of 10…25 wt.% and a pressure of 0.1…0.9 MPa. Such atmosphere is needed for the oxidation reaction of titanium powder. For spheroidization particles of the composite powder were added into the plasma jet and sprayed into a steel cylinder with a length of 1 m filled with argon. The degree of spheroidization was determined using the form factor of the particles by optical metallography. The power of the plasma jet was varied from 30 to 40 kW. The resulting powders are characterized by a complex geometric shape and the development of surface relief of the particles. Application of SHS powders, in contrast to the agglomerates, allows forming high-density coating of eutectic composition promoting improvement physical and mechanical properties. Parameters of friction and wear coatings consisting of carbide ceramic powders and ceramic oxide powders obtained by self-propagating high-temperature synthesis are investigated. The coatings obtained of powder Al 2O 3-30% TiO 2-12.5% MoS 2; produced by self-propagating high-temperature synthesis, are 1.2 times more wear-resistant with the lubricant and 1.3 times - under dry friction for cast iron and steel than the coating obtained from the powder Ni80Cr20-12.5% MoS 2-55% TiC.

composite powders, solid lubricant, synthesis, spheroidization of particles, plasma jet, powders investigation