THE INFLUENCE OF WORKPIECE POSITION ON THE PALLET DURING LASER CUT-TING ON THE FORMATION OF THE THERMAL EFFECT ZONE

10.25712/ASTU.1811-1416.2023.03.012

Abstract

In this paper, the properties and material structure of the heat-affected zone, arising during laser cutting of metal, depending on the location of the workpiece on the pallet: over the protrusion and between the protrusions of the pallet were studied. Significant differences in properties and structure at these sites are shown. Recommendations on the location of the workpiece relative to the pallet's projections are given. Material properties in the cutting zone above the pallet ledge and between the ledges are significantly different. The microhardness values in the area above the pallet projections at the edge are about 50 % less than in the area between the projections. As we move deeper into the sample, the difference decreases. Magnesium content is almost two times lower in the zone above the protrusions than between the protrusions. In the surface layers of the blank in the zone above the projections the sizes of inclusions are larger than in the depth. This is caused by additional hardening of the workpiece metal located between the projections, and a longer contact with the bath of liquid metal due to the difficulty of its removal when cutting on the ledge of the pallet. Removal of the defective layer by milling to a depth of 0.5 mm levels out the difference in metal properties in the area above the pallet ledge, between the ledges and in the depth.