SURFACE ROUGHNESS IN LASER BEAM CONTOUR CUTTING
In the industrial engineering field, there are several methods able to be applied in order to materialize a cut contour. Not in all cases, the removable rate of material and cutting accuracy are satisfactory and the costs are sufficiently low. In such situations, some nonconventional processing methods could ensure a fast and appropriate solution for cutting workpieces. Knowing that the surface roughness is a parameter of real interest in almost cases when the accuracy is considered, definitely it will decide the chosen manufacturing process. Due to its influence on the surface properties and on the number of subsequent machining operations, the required roughness value could be taken into consideration when selecting the cutting process. Among distinct nonconventional processes which can be applied, in the present paper, the laser beam procedure was established as being the right choice in order to accomplish certain objectives. A theoretical analysis showed that some of input factors for laser beam process are able to affect the sizes of the surface roughness parameters and could be represented by cutting speed, pressure of the gas sent to the processed area, the power developed in the contact area between the laser beam and workpiece, the process efficiency and the frequency of the laser beam. An experimental research was designed and developed, in order to highlight the influence exerted by the above mentioned factors on the size of the Rz surface roughness parameter. Using the experiments planning, it was developed a series of experiments, in order to show the intensity of effects exerted on the surface roughness by the process input factors.
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