Impact of Workpiece Position on Pallet during Laser Cutting on Heat-Affected Zone Formation

Abstract

The study in this work focuses on the properties and structure of the material in the heat-affected zone that occurs during laser metal cutting, depending on the positioning of the workpiece on the pallet: above the protrusion and between the protrusions of the pallet. Significant differences in properties and structure in these areas are demonstrated. Recommendations on the positioning of the workpiece relative to the pallet protrusions are given. Material properties in the cutting zone above the pallet protrusion and between the protrusions differ significantly. Microhardness values in the zone above the pallet protrusions at the edge are approximately 50% lower than in the zone between the protrusions. As the analysis moves deeper into the sample, the difference decreases. The magnesium concentration is nearly two times lower in the zone above the protrusions than between the protrusions. In the surface layers of the workpiece above the protrusions, the sizes of inclusions are larger than in the depth. This is due to additional quenching of the metal in the workpiece located between the protrusions and prolonged contact with the bath of liquid metal due to difficulties in its removal during cutting on the pallet protrusion. Removing the defective layer by milling to a depth of 0.5 mm neutralizes the difference in the material properties in the zone above the pallet protrusion, between the protrusions, and in the depth.