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METALWORKING EQUIPMENT METALWORKING EQUIPMENT
AND TOOLS AND TOOLS
Fig. 2 shows images of the treated surface It seems promising to use this
Prospective by two different methods. The picture on the left technology not only for cleaning the surface
(a) clearly shows the traces of «plowing» and from strong oxide layers, but also for

method for pre- cuts with abrasive particles. These craters and preparing the surface before coating. At the
irregularities significantly increase the surface first stage, the surface is smoothed using a
treatment of the roughness. On the right, a subsequent water- microabrasive method, and at the second
jet treatment was carried out. The surface is stage, the surface is cleaned and hardened
hard alloy before smoothed and characterized by low roughness. with a water jet at a pressure of about 3000

At MSTU ''STANKIN'' experiments were bar.
applying the carried out on the surface treatment of hard alloy
by the water-jet method. Figure 3b shows that
coating the grooves from grinding, segregation of the
cobalt phase, and contamination disappeared on
In the process of creating cutting tools, the the surface of the sample.
preparation of the surface of the tool before applying the
coating plays an important role in order to increase its
durability and wear resistance. The preparation process
affects the microtopography, integrity and surface finish of the tool material, which in turn
affects the adhesion and strength of the coating to the surface. Among the methods of such
exposure are well known such as microabrasive and water jet.
Micro-abrasive treatment removes material through the interaction of a jet of air or water
containing an abrasive with the surface of the material being processed. A microabrasive jet is
formed by passing a stream of gas or air containing abrasive particles (Al2O3 or SiO2 powder)
with a size of 10 to 50 microns through an orifice - a nozzle with a diameter of 0.4-1.2 mm -
under pressure up to 6 bar. The resulting velocity of the transported particles is from 150 to 300
m / s [1].
Fig. 1 schematically shows a microabrasive blasting machine. If water is used as a
medium for transporting abrasive particles, Fig. 2. Comparison of microabrasive jet and hybrid treatment [5].
then the process is called ''wet microabrasive
processing''.
High fluid pressure water jetting is an
extremely flexible and versatile processing
method. It has found applications in various
industries in processes such as cleaning, surface
defect removal, cutting, water jet hardening,
material surface modification processes.
Water jet hardening is the process of
mechanically hardening a surface through
the action of high velocity water droplets that
cause local plastic deformation. As a result,
significant residual compressive stresses arise
а
in the surface layer, which contribute to an Fig. 3. Surface treatment by water-jet method. b
increase in surface hardness and fatigue life.
Also, the advantages of this method include:
Weiss Daniel, PhD student.
Fig. 1. The basic scheme of microabrasive blasting [3]. the absence of surface contamination after S. V. Fedorov, scientific adviser, candidate of technical sciences, associate professor.
processing and the absence of thermal effects Department ''Highly efficient processing technologies'' MSTU ''STANKIN''.
[4].
The hybrid method is a combination of References:
micro abrasive blasting and conventional water
blasting. In [5], this method is proposed as an innovative method for removing the oxide film 1. C.J.C Rodríguez, Cutting edge preparation of precision cutting tools by applying micro-abrasive jet machining and
brushing, Mesogeometry of the cutting edge. ISBN 978-3-89958-713-5.
from the surface of titanium alloys. First, the method of micro-abrasive blasting is used to 2. F.Tikel, Schneidekantenpräparation-Ziele, Verfahren, Methoden. Berichte aus Industrie und Forschung. ISBN 978-3-
remove the film to the required depth, then ordinary blasting is used to clean the surface from 89958-494-3.
abrasives, level the surface, reduce roughness, that is, to achieve a ''polishing'' effect. The 3. Modeling of material removal in mechanical type advanced machining processes: a state-of-art review Neelesh K. Jain,
Vijay K. Jain.
results showed that a combination of these methods is effective for surface cleaning. 4. The Impact of Plain Waterjet Machining on the Surface Integrity of Aluminium 7475 F. Boud, L. F. Loo, P. K. Kinnell.
In most cases, abrasive particles must be removed from the surface of the work piece, 5. Parametric effects on grit embedment and surface morphology in an innovative hybrid waterjet cleaning process for alpha
since such particles can initiate cracks [6], which reduces fatigue strength and, according to case removal from titanium alloys.
6. Singh, J. and S.C. Jain, Mechanical Issues in Laser and Abrasive Water-Jet Cutting. Jom-Journal of the Minerals Metals &
[7], surface contamination with abrasive particles can also cause serious problems during Materials Society, 1995.
subsequent application coatings for parts and tools. 7. Chen, F.L., et al., Minimising particle contamination at abrasive waterjet machined surfaces by a nozzle oscillation
technique. International Journal of Machine Tools and Manufacture, 2002.

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