Transcript IMPROVEMENT OF WEAR-RESISTANT QUALITIES OF ALUMINUM ALLOY

IMPROVEMENT OF WEAR-RESISTANT
QUALITIES OF ALUMINUM ALLOY BY
GAS-THERMAL SPRAYING OF HIGHTHICK COATINGS
Developed by student of 632AM
Alexandra Krivtsova
Scientific Supervisor – Fedor Vashkevich
English Supervisor – Victoria Kuzmenko
The general tendency in mechanical
engineering is the reduction of metal
consumption. It dictates the replacement
of steel basic caterpillar wheels by more
light ones, for example, made of
aluminum alloys. In consequence it is
necessary to reinforce the sections that
are most of all exposed to the wear by
more hard materials.
The sketch of track wheels
This is a complex problem and its
solution should be found in three
directions:
 choosing of the form of groove;
 choosing of the wear-resistant
coating;
 choosing of technology of
application of coating.
Distribution of forces during the basic
wheel movement upon the chain track
Groove configuration with symmetrical
cross section and screw gear
Determination of wear-resistant coating

mechanical-and-physical properties of
sprayed coatings
The elaboration of application
technology of wear-resistant coating.
Nowadays the gas-thermal spraying of coatings is the
most multiple-purposed and it allows to spread wearresistant materials in the form of powder and wire. If to
compare electric arc, gas-oxygen and plasma spraying,
electric arc spraying is the most competitive. The working
conditions of electric arc metallizing gun has a great
influence on the final hardness of the 40Cr13 steel
coating because of carbon burning in coating. Especially
the arc voltage influences on the carbon content and
hardness. The voltage increase on the arc more than 35
V leads to significant decreasing of the carbon content
and hardness. That is why metallization of coatings is
conducted with 30 V and current= 200 – 220 A. This
mode allows to save the hardness of the metallised
coating near 60-65 HPA.
The general view of stand for application of
protection coatings on wheel rims
Micro-structure of metallized coating on
aluminum alloy in the groove with
straight gears
Mechanized infantry combat vehicle
Tracked military car
Semitracked quad
Conclusions
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4.
The conducted analysis of methods of getting
protective coatings showed the preference of electric
arc metallization as the most efficient and easy
method.
40Cr13 has been chosen as a suitable material for
metallization.
Groove configuration with symmetrical cross section
and screw gear has been chosen due to the
distribution of forces during the basic wheel
movement upon the chain track.
The stand for application of protection coatings on
wheel rims was made by plasma technology
laboratory in PSACEA.
Thank you for your
attention!