Study of the Impact of the Powder Laser Cladding Position on the Parameters of the Cladded Layer

Proceedings of the Estonian Academy of Sciences 2020
Andris Ratkus, Toms Torims

This research describes the realization of a hitherto unexplored aspect of laser cladding technology – laser cladding with powder – to provide cladding in the overhead (OH) position. This position is important for bore claddings where objects are large and the bore cannot be orientated vertically to ensure a constantly vertical cladding position, or when the object cannot be secured in a chuck and rotated to provide a constantly flat (F) cladding position. Laser cladding experiments have been performed to determine the dependence of the laser cladding characteristics on the cladding position and nozzle angle. Safe laser cladding using powder and a coaxial nozzle in the OH position is possible with a nozzle angle α = 36°. In the paper, mathematical expressions were developed for predicting such characteristics as the cladding thickness (𝐻), cladding area (𝐴𝐶) and dilution (𝐷𝐶) of the laser cladding technology, by introducing the parameter 𝐺, in which the obtained results are predictable and useful. The introduced parameter 𝐺 consists of the above laser cladding parameters combined with simple equations, making it possible to predict the results. It has been experimentally proved that laser cladding with powder can be successfully implemented in the flat (F), vertical up (VU), overhead (OH) and vertical down (VD) positions, therefore laser cladding with powder can be used for bore claddings. The influence of the positions F, VU, OH and VD on the cladding characteristics 𝐻, 𝐴𝐶 and 𝐷𝐶 has been experimentally determined. Hardness measurement results show a correlation between the melt pool temperature distribution and microhardness (HV) values. The knowledge acquired in this research is adaptable and also applicable to the development of external surface cladding.

Keywords
powder laser cladding, predicting cladding characteristics, Stellite® 6
DOI
10.3176/proc.2020.3.08
Hyperlink
https://doi.org/10.3176/proc.2020.3.08

Ratkus, A., Torims, T. Study of the Impact of the Powder Laser Cladding Position on the Parameters of the Cladded Layer. Proceedings of the Estonian Academy of Sciences, 2020, Vol. 69, No. 3, pp. 257-265. ISSN 1736-6046. e-ISSN 1736-7530. Available from: doi:10.3176/proc.2020.3.08

Publication language
English (en)