In the master's thesis, we designed an analytical mechanical model of chip breaking with
which, based on the obtained results, it is possible to predict the degree of mechanical
deformation or chip breaking during pulsating supply of coolant to the cutting zone during
turning. In fine machining, especially in the turning of difficult-to-machine materials,
including the Ti6Al4V alloy, chip problems often occur. As one of the solutions to this
problem, a pulsating supply of coolant is offered, where with increased pressure we
additionally deform the chip to such an extent that it breaks. The amount of chip deformation
as a consequence of coolant jet action was to be described by model development.
In order to verify the adequacy of the designed analytical model, experiments were
performed in the experimental part. The influence of turning process parameters and highpressure coolant parameters on chip fracture was analyzed. To determine how the jet acts on
the chip, we experimentally described the shape of the cross section of the jet and the
pressure distribution of the coolant jet that hits the chip and the cutting tool.
It was found that the process parameters of turning (feed, depth of cut) and the parameters
of pulsating high-pressure supply of coolant to the cutting zone have a great influence on the
process of chip breaking. Taking into account the determined pressure losses of coolant in
the analysis of the pressure acting on the chip, we found that the designed analytical
mechanical model of chip fracture is suitable for predicting the required coolant pressure for
critical deformation or fracture of the chip.
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