Laser weld surfacing with wire is an excellent complement of conventional repair clad-welding techniques. The key advantage is the ability to produce a small weld cladding with a small heat-affected zone. Laser weld surfacing is therefore suitable for materials that are sensitive to thermal changes. The main purpose of the diploma work was to determine which shape of the pulse of laser cladding is suitable for clad-welding on the following tool steels: 1.2311, 1.2312, 1.2343, 1.2344, 1.2767, 1.2379, 1.2550. In a planned study, a correlation between the shape of the laser beam pulse and the shape of the weld cladding, hardness and hardness gradients were determined. The research was done using the principal component analysis and by analysing data with program named Surfer. By analysing the principal components, we established the correlation between the shape of the laser beam pulse and the shape of the weld cladding, which makes it easier to choose the suitable shape of the laser beam pulse on the selected tool steels. Using color graphic representations of hardness we showed the hardness of the cross-section of the clad-weld. After reviewing the hardness graphs we found that it would be useful to make graphs of hardness gradient. The gradients are the highest where cracks are visible on images of weld claddings. Thus, our conclusion is that pulses that generate large hardness gradients are not suitable for laser clad-welding on tool steels.
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