The laser metal deposition is an advanced manufacturing technology enabling the production of large-sized parts and partially or completely elimination of machining and welding. The process is characterised by a non-uniform local heating of the buildup leading to a stress distribution, which may exceed the yield strength of the material and leads to loss of dimensional accuracy. The interlayer dwell time has a strong influence on the temperature field. The effect of the interlayer dwell time on the distortion and the stress distribution during laser metal deposition of a single-pass wall on the edge of 2 mm thick plate was studied experimentally and numerically. The deposited material was IN625 and the substrate material was AISI 316. A decrease of the residual displacement, due to a uniform shrinkage after the deposition of the last layer and a lower level of the residual compressive longitudinal plastic strain, has been observed in the studies without a dwell time. The peak increment of the free edge displacement corresponds to the first layer and hence the subsequent layers will be deposited on the already plastically deformed buildup. The tensile residual longitudinal stress near the top of the buildup and transverse stress near the edges of the buildup is higher than yield strength in the studies with dwell time.

Present paper is about experimental investigation coating quality obtained by plasma transferred arc (PTA) welding in relation to the material-and process parameters. The aim of work is to get different materials coatings with satisfactory properties, which could be used at hybrid bevel gears further. The main idea of this method is to create bi-metal workpieces by deposition one material over other, then form it by thermo-mechanical processing. Using hybrid bevel gears would reduce costs because the gear would not be made of one expensive material, but has only a functional surface layer with cheap core. In is investigation steel cylinders made of C22 are coated with the higher-quality heat-treatable different steels: 41Cr4, 50CrV4 and 100Cr6 using PTA welding. Coating quality is depend on many deposition parameters, such a feederate, current, preheating temperature etc.

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