An investigation of the reflection phenomena in the direct energy deposition process based on the stainless steel wire using a fiber laser

Abstract

The purpose of this master's thesis is to study the phenomenon of the reflection, which occurs as a result of the melting of stainless steel 316L wire under the influence of emission from a high-power fiber laser in the process of direct energy deposition. Interest in the topic is due to the fact that uncontrolled reflection can go beyond the keyhole and reduce the efficiency of the process. Based on this, an experiment was conducted to determine the shape, position and amount of reflected energy. The shape and position was determined using a thermo- and a high-speed cameras. The reflected power was expressed in relative values. It was found that the percentage of energy lost can reach 35%. A tendency of a decrease in reflection with an increase in input power was also noticed, and the most favorable angle for processing stainless steel 316L wire was determined.