INCREASE OF THE OPERATIONAL PROPERTIES OF WELD AND PLASMA COATINGS USING NANOPOWDERS

Abstract

In this work, studies concerning determination of the oxide nanoparticles effect on structure and performance of the welds and plasma coatings were conducted. Ways ofintroducing nanodisperse refractory powders to the weld pool and how to cover with thedeactivation of nanoparticles powder were determined. Introducing of the nanoparticles in the molten pool during the deposition and the coating was carried out by preparing a powder mixture by mechano-chemical processing in special high-energy intensive planetary mills. Structural studies of welds with nanooxides additives in the weld pool showed the formation of milled dispersed structure with microhardness 264-304 MPa. Statistical mean value of the number of non-metallic inclusions was defined. Mechanical testing of welds showed growth of the yield as well as tensile strength, when titanium and aluminum nanooxides were introduced into the weld pool. The most significant effect on these parameters has aluminum nanooxide in an amount of 0.5 vol.%, increasing the yield strength by 49 % and the tensile strength by 23 %. The toughness is mostly affected by titanium oxide in an amount of 1 vol.%., increasing its value by about 2 times. In turn, the introduction of alumina nanopowder in quantity 1,5 vol.% into the plasma coatings allowed to reduce friction and increase wear resistance of coatings by 2-3 times.