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METALWORKING EQUIPMENT METALWORKING EQUIPMENT
AND TOOLS AND TOOLS
TESTS OF METAL CUTTING TOOLS COATINGS

Thus, when increasing the dynamic FOR MICRO-ABRASIVE WEAR
characteristics of the drives, special attention
should be paid to the table rotation drive,
since in the used control system (Sinumerik
840D, Siemens) it is a slave, adjusting to Microabrasive wear is the process
the master drive of the cutter, while the of destruction of parts operating under
connection between them is realized through sliding or rolling friction, in the presence of
an electronic gearbox. loose abrasive particles in contact between
rubbing surfaces with a size of less than 100
microns and a hardness, greater hardness
of materials of tribo-couplings. This type of
Fig. 7. Graphs of the kinematic errors of the cutter drives (a, b) wear is experienced, for example, by open plain bearings, machine tool guides, gears of open
and the table (c) with various settings gears and gearboxes, hinged joints of chains of various machines, etc. In addition, due to the

Findings formation of wear products involved in friction processes, the possibility of oil coking, ingress
● Experimental studies of the kinematic error of the 5320F4 machine tool with a new generation abrasive particles into the lubricant when the tightness of the lubricating system is broken,
of accuracy class P with direct drives of rotation of the cutter and work piece showed a significant almost all surface layers of tribo-couplings are also under the influence of microabrasive wear.
increase (more than 5 times) in the kinematic accuracy, which is higher than the accuracy of the The study of this type of wear is relevant for parts and tools with wear-resistant thin-film
class A machine. It was found that the greatest influence on the accuracy of the machine has coatings deposited using PVD and CVD processes, when choosing the optimal technological
dynamic characteristics of the table drive. mode for applying the same coating
● New generation machines for accuracy classes from H to A should be based on a single material and when studying the effect
machine model of the same size with 90 - 95 % standardization of parts. of the chemical composition, type and
● Due to a significant increase in the manufacturability of units that provide shaping, the production physical and mechanical properties
of new generation machine tools does not require special equipment and technologies (master of various coatings. The international
machines for processing worm wheels and worms, etc.). This production can be realized not standard EN 1071-6: 2007 has been
only at specialized enterprises, as in the manufacture of traditional gear hobbing machines, but developed for testing microabrasive
also at any machine-tool plant, which was shown by the practice of manufacturing horizontal wear of such coatings. Abroad, this type
machines at LLC Morena (Kolomna) and vertical machines at JSC SASTA (Sasovo). of testing is most often used to assess
the tribological properties of coatings,
along with indentation processes and
friction tests [1].
Determination of wear parameters
under conditions of microabrasive wear
A.V. Novikov, is based on microscopic measurement
post-graduate student of the Machine tools Fig. 1. General view of the equipment for testing of microabrasive
department of MSTU STANKIN wear. of an indentation obtained at point
. contact of two mating bodies - a freely
References: rotating steel ball and a stationary flat
1. Bushuev V.V., Kuznetsov A.P., Sabirov F.S., Khomyakov V.S., Molodtsov V.V. State and directions of development of scientific
research in machine tool industry // STIN. 2015. No. 11. pp. 12 - 20. sample with a coating (or without a coating) in the presence of an abrasive suspension in the
2. Bushuev V.V., Novikov V.A. Directions of development of gear-processing equipment // Bulletin of MSTU STANKIN. 2015. No. friction zone. A prerequisite for measurements is a clear image of the wear print and contrast
2 (33). of the coating and substrate, determined by the roughness of the coated sample. Tests are
3. Bushuev V.V., Naletov S.P. Heavy gear cutting machines. Moscow. Mashinostroenie, 1986. 280 p.
4. Levashov A.V. Basics of calculating the accuracy of kinematic chains of metal-cutting machines. Moscow. Mashinostroenie, carried out in the conditions of an inclined position of the sample and pressing the ball against
1966. 211 p. it due to its own mass. The presence of a certain amount of abrasive suspension in the area of
5. Molodtsov V.V., Bushuev V. V. Methodology for modeling feed drive mechanisms for CNC machine tools // Bulletin of mechanical friction between the ball and the sample provides a quick impression with wear of the coating
engineering. 2015. No. 8.
6. Molodtsov V.V., Bushuev V. V., Evstafieva S.V. Simulation of control loops of the servo feed drive // STIN. 2016. No. 3. pp. and substrate.
7 - 14. The load in the contact friction zone is constant when using the same balls (dimensions,
7. Gilovoy L.Ya., Molodtsov V.V. Designing gear hobbing machines with hightened rigidity // Handbook. Engineering journal with roughness parameters and material) and their positioning relative to the test specimen. The
annex. 2013. No. 2 (191). pp. 40 - 45.
8. Makarov V.M., Churilin A.V., Korendyasev G.K. Technological support for the accuracy of gear parts based on new technologies wear conditions of the samples are the same at the constancy of the balls, the rotation speed of
and modeling // Machine building technology. 2010. No. 7. 27 p. the drive shaft, the test time, the use of the same abrasive suspension and a constant amount
or rate of its introduction.
The principle of microabrasive wear is the action of cohesively strong micron-sized abrasive
particles contained in an abrasive suspension, which are located in the gap between two surfaces
during friction. At the same time, they cut the contacting surfaces, acting as an abrasive tool.
CREATE A BETTER FUTURE Under conditions of rotation of a ball with a large diameter relative to a stationary coated

TOGETHER WITH OUR CUSTOMERS specimen, abrasive particles are removed from the test specimen the roughness protrusions
and the coating itself on the dotted surface, polishing and smoothing it, with the formation of a
spherical wear segment.
Equipment for determining wear parameters using microabrasive wear tests consists
of a Tribotester PC102 tribotester (manufactured by Plasmacenter LLC) with a set of balls,

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