Analysis of the influence of LMD laser surfacing parameters on selected propertiesof the surfacings produced from HS6-5-2c powder on 1.4923 steel

In: Bulletin of the Military University of Technology, Band 72, Heft 1, S. 115-130

Abstract

This paper presents the results of testing surfacings produced by LMD (Laser MetalDeposition) laser deposition technology at different laser beam parameters. On the surface layer ofrectangular-shaped samples made of 1.4923 steel, multiwall surfacing was produced from HS6-5-2cpowder with different degrees of coverage. As part of the laser deposition verification and testing,surface topography, microstructure and hardness tests were carried out in the deposition zone, heataffectedzone and the zone of the parent material. The surface of the surfacing and the microstructurein cross-section were observed on an optical microscope with fibre-optic image transmission. Hardnessmeasurements were made in the cross-section of the sample using a Vickers FLC-50A hardness tester.Based on the observations, it was found that the obtained surfacings have a regular and repeatableshape. There were no welding defects on the surfaces of the produced surfacings and in the zoneof fusion of the surfacing material with the substrate material. The hardness of the surfacings wasobtained in the range of 500-700 HV0.1. The produced surfacings by LMD technology were subjectedto erosion resistance tests, which showed significantly higher (about 5. times) resistance to erosionwear of the produced surface layers (surfacings based on HS6-5-2c powder) in comparison with thesubstrate material, i.e. steel 1.4923.Keywords: steel 1.4923, HS6-5-2c alloy powder, LMD laser deposition, surface layer, depositiongeometry, chemical composition, microstructure, hardness, erosion