Structural-phase mechanisms of controlling the structural and functional alloys complex surface properties by combined thermal, ionic and deformation effects

The perspective of using combined thermal, ionic and deformation effects as a tool for purposeful modification of the structural and phase states of the near-surface region of a wide class of structural and functional metal materials to increase the durability, quality and reliability of parts, products and structures of transport engineering and medicine has been proven. Steels 40X13, 08X18N10, 9Г2ФА, aluminum alloys AMg6, D16, cobalt alloy Co-Cr-Mo-W, brass LS59-1, titanium alloy VT6, multi-component alloys Fe81B7Si1P10Cu1, CrMnFeNi2CoCu, etc. were studied. Co-Cr-Mo-W and VT6 alloys were produced using various technologies, including additive (3D printing). Combined effects based on ultrasonic impact treatment (USIT), including the addition of strengthening ceramic powders of various fractions, high-frequency treatment with steel balls, electrospark alloying, laser irradiation, shot blast hardening, heat treatment, low-energy ion irradiation, etc., were used. This made it possible to implement: mechanical nanostructuring of near-surface layers, activation of mechano-chemical reactions, alloying/surfacing, introduction of compressive stresses, increase in thickness of modified layers and increase in their wear and corrosion resistance, reduction of roughness and improvement of antibacterial properties. As a result, for example, for the VT6 alloy, the instrumental hardness increased up to ~4 times (up to 12.8 GPa); reduced by ~2.5 times the coefficient of friction during 30 test cycles and up to ~20 times the loss of material due to wear; heat resistance improved by ~1.5 times and corrosion resistance by ~7.5 times in a 3.5% NaCl environment, compared to the initial state.