On the role of capillary and thermo capillary phenomena on microstructure at laser cladding

Laser cladding (LC) is a widely diffused additive manufacturing technology, but some shortcomings such as narrow processing window still limit it. The hydrodynamic model of LC for the calculation of the microstructure of built-up layer is developed considering contact angle of the melt with the substrate. The study of capillary phenomena, the influence of contact angle on characteristics of a built-up layer is held. The powder jet radius showed dissimilar response to the contact angle change depending on the comparison to the melt pool width. The track spreading due to contact angle change is shown to decrease the average crystalline size of the clad layer. The results provide the insight in to the LC technology can be used for the process optimization.