Excessive wear of functional surfaces of products and tools is a huge cost because the worn tools must be replaced with new ones or repaired with repair welding. The challenge here is the determination of welding parameters but above all the geometry of a weld bead. The aim of the thesis was to determine the optimal weld step-over to achieve a flat surface. The experimental work consisted of wire and arc additive manufacturing. We used a 3-axis CNC manipulator and a MIG/MAG welding machine with a VAC 60 filler wire. Experimentally, we used a pair of welds with a growing pattern at different process parameters and measured the surface of the samples with a 3D body shape gauge. These forms were analyzed using an algorithm developed as part of the thesis. The criterion of minimum difference between the maximum and the saddle between the welds and the ratio of the heights of the welds in the pair was used to determine the optimum degree of welds overlap. We found that the linear energy input influences the most on the shape of the weld. The surface tension of the melt plays a vital role in weld surfacing.
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