Prediction of coating geometry: theory and experiment

Abstract

In this contribution we present a comparison between laser clad experiments and model predictions of the entire geometry of laser deposited multi-layered coatings. Recently we have shown that the recursive model describing the geometry of laser clad coatings combined with experimental track characteristics leads to specific functions describing the geometry of coatings formed by overlap of individual tracks depending on the processing parameters. The recursive model provides an adequate description of the whole geometry of the coating from the Height H and width w of a single laser track for any overlap ratio OR. We have shown that the height and width of a single track are well correlated with the main laser cladding processing parameters for both coaxial and side cladding set-ups. Combining these two approaches leads to a prediction of the complete geometry of laser clad coatings from a number of basic processing parameters. These parameters are: Feeding rate F, Laser beam scanning speed S and overlap ratio OR. The functions that describe the height and waviness of the final coating are the same for both coaxial and side cladding set-ups. These model predictions lead to very simple, yet very accurate predictions of the entire geometry of the laser deposited layers.