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частицами SiC является более эффективным по сравнению с гальваническим
хромированием для повышения его износостойкости при испытаниях жестко
закрепленным абразивом. Его износостойкость повышается в 93 раза по сравнению с
немодифицированным сплавом. При испытаниях незакрепленным абразивом более
эффективным оказалось высокоскоростное газопламенное напыление покрытий с
добавлением VC, которое повысило износостойкость алюминиевого сплава в 7–9 раз.
Поскольку проведенные экспериментальные исследования убедительно обосно-
вывают эффективность предложенных способов упрочнения, то их можно рекомен-
довать как альтернативу экологически небезопасной технологии хромирования.
Ключевые слова: алюминиевый сплав, лазерно модифицированные слои, кар-
бид кремния, погонная энергия, высокоскоростные газопламенные покрытия,
карбид ванадия, включение кобальта, жестко закрепленный абразив, незакреп-
ленный абразив, износостойкость, коррозионная стойкость.

ANNOTATION
Zadorozhna Kh. R. Increasing of the abrasive wear resistance of aluminum
alloys by forming coatings strengthened by SiC and VC carbides. The manuscript.
The dissertation for the degree of candidate of technical sciences, speciality 05.02.01
Materials Science. Karpenko Physico Mechanical Institute of the National Academy of
Sciences of Ukraine, 2019.
The dissertation is devoted to establishing the laws of the surface layers structure
formation of aluminium alloys by laser modification with SiC particles and high-speed

flame spraying of coatings with the addition of VC, which is proposed as alternative
hardening methods compared to galvanic chromium plating. In addition, the wear resis-
tance of strengthened layers by testing using a rigidly fixed and not fixed abrasive, as well
as their corrosion-electrochemical properties in aqueous media with pH≈7 were estimated.
To obtain wear-resistant Al – SiC composite layers up to 1.5 mm thick the regime of
laser modification of the surface by silicon carbide particles was optimized in the range of
740...1100 J/cm of the linear energy input.
Based on the complex of studies, the influence of both the sizes of vanadium carbides
and the presence of cobalt inside the strengthened layers obtained by high-speed flame
spraying on the wear resistance and a wear mechanism under various test conditions were
established.
The methods of surface hardening of B95 aluminium alloy were ranged relative to
unstrengthened alloy by the wear resistance level under various test conditions, as well as
their energy consumption and environmental safety. It is revealed that to increase the wear
resistance at testing with fixed abrasive, environmentally friendly laser modification of the
alloy surface by SiC particles is more effective than galvanic chrome plating. At its using
the wear resistance of the strengthened layers increases by 93 times relative to non-
modifications alloy. At wear testing with a not fixed abrasive, the coating using high-
speed flame spraying by the VC particles was more efficiently increased the wear
resistance of an aluminium alloy (up to 7–9 times).
Keywords: aluminium alloys, laser-modified layers, silicon carbide, linear energy
input, high-speed flame coatings, vanadium carbide, cobalt inclusions, wear resistance,
rigidly fixed abrasive, not fixed abrasive, corrosion resistance.