Abrasive water jet cutting (AWJ) is a versatile contour cutting process. High pressure accelerates the water jet through a narrow nozzle, where it is mixed with abrasive grains. Due to the high velocity and mass contribution of the abrasive particles, a high-kinetic energy jet is obtained, which erodes workpiece material. When cutting, we are limited by the thickness of the workpiece, which depends on the power of the jet itself. This process is characterized by an occurrence of waveform, especially in the lower part of the cut, which is undesirable, since it negatively impacts on the geometry of the workpiece. We reviewed literature related to the typical phenomena on the surface of the workpieces after cutting with the AWJ. In the experimental part we studied the influence of the abrasive mass flow rate and the feed speed rate on the characteristics of the surface after engraving with the AWJ and sought a connection with the formation of the waviness. Experiments were done on aluminum alloy 5083. The depth of the engraving was limited to a maximum of 3 mm, the Zeng's equation was used to calculate the theoretical depths of the cut. The exponents of this equation were successfully adapted and more precise forecast of the depth for the engraving was achived. The results were evaluated using graphs of the power spectrum. It has been found that for the selected parameters in the feed speed range from 500 to 900 mm/min and mass flow rate from 12 to 48 g/min, there is no formation of waviness yet.
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