The abrasive water jet cutting process (AWJ) is one of the contour cutting processes in which abrasive grains are added to the high-speed water jet. Water, along with the abrasive, hits the workpiece, which removes material. The cutting process is suitable for the treatment of various materials, including metals, stone, glass and organic materials, without the presence of a heat-affected area. Despite the good features of the machining process, the greatest disadvantage is the lower cutting accuracy. One of the typical features of machining when cutting with AWJ is the stria formation. In this work we have reviewed the literature in relation to the characteristic phenomena on the surface of the material after cutting with AWJ. In the experimental part of the work, an abrasive dosing system with a rotating wheel was installed on the AWJ cutting machine, which feeds the abrasive into the mixing chamber of the cutting head. With mentioned dosing system we engraved the material. In order to find possible connections for the formation of stria on the surface of the workpiece, we made engravings of depths of up to several millimeters in aluminium alloy and structural steel, increasing the cutting depth by changing the machining parameters. Using digital microscope, we analyzed the topography of the engraving surfaces and evaluated the results by processing the data. The results were plotted using spectral density power graphs. We find that the power of the spectral density increases at certain frequencies, which is the result of increasing the depth of the cut.
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