Papers by Keyword: Laser Beam Machining

Abstract: This paper addresses the unique challenges in processing aluminum materials within metal forming technology, specifically focusing on complex wear conditions involving abrasion and adhesion. A promising research approach to avoid abrasive and adhesive tool wear and reduce the friction coefficient towards aluminum alloys is the use of sufficiently smooth CVD diamond coatings. To achieve this, two approaches are considered. First, wear resistance is enhanced by using tool inserts made of carbide or a tungsten alloy, directly coated with CVD diamond. Second, the friction coefficient is selectively influenced or reduced by refining the polished CVD diamond coating through laser ablation. The study investigates the impact of these surface treatments on friction coefficients during both dry and lubricated forming processes involving the aluminum alloy EN AW-5182. Comparative analyses of various surface treatments are conducted against reference tests using diamond-like carbon (DLC)-coated tools. Through application-oriented strip drawing tests, the paper systematically examines how different surface smoothing techniques affect the coefficient of friction. This research provides valuable insights into optimizing metal forming processes for aluminum alloys through tailored surface treatments, advancing our understanding of friction dynamics in these specific manufacturing conditions.

Abstract: Copper is one of the best light metal based on their properties and usefulness in the field of precision parts.Emergence of advanced engineering materials, unusual size and intricate shape of jobleads towards the use of non-conventional machining processes. Laser beam machining (LBM) is one of them which is non-contact and optical-thermal process used for machining almost all range of engineering materials. Artificial neural network is used to develop a prediction model representing complex relationship between the input (process) parameters and output parameters (responses). In this present paper, micro-drilling has been performed on 0.2 mm thickcopper sheet by Nd:YVO₄ laser of 12 kW. Design of experiment is performed by Taguchi's L9 orthogonal array. Here, hole taper and HAZ width have been observed varying the process parameters like laser beam power, pulse frequency, scanning speed and number of pass. Experimental results are analyzed by S/N ratio and verified by confirmation experiment. A feed forward back propagation ANN model is also developed to predict the responses at any combination of process parameters within the limit.

Abstract: The laser beam could be obtained by means of a laser diode. The amplification process develops inside the optical fiber. In the laboratory for nonconventional technologies from the Gheorghe Asachi Technical University of Iași, there is an ytterbium fiber laser equipment able to ensure conditions for obtaining a laser spot having a diameter of 30 μm diameter and a wavelength of 1070 nm. This paper purpose is to highlight the solutions that we may consider for a workpiece clamping device. On the bases of the general known information concerning the devices used in order to machine workpieces on machine tools, an ideas diagram was elaborated. Finally, a device practical solution was designed and materialized, this device was used in order to develop some experimental researches.

Abstract: The laser beam machining uses the effects generated at the impact of the workpiece surface with a laser beam that has adequate energetically and spatial - temporal characteristics. It is known that, as result of the laser beam impact with the workpiece material, local chemical and physical effects are signalized. In order to study such effects and simultaneously the technological possibilities of laser beam equipment, some experimental researches were developed on an Ytterbium fiber laser equipment of 300 W. Movements of the laser spot along established trajectories were ensured, changing the sizes of the machining parameters. The influence exerted by the machining parameters and by the materials characteristics on the material removal from the test piece was highlighted. The surface layer modifications were also studied.

Abstract: This work presents investigations of cavitation properties of different austenitic microstructures formed by laser beam machining of X5CrNi18-10 and C45 steels. X5CrNi18-10 steel was alloyed with TiC and Mn powders and surface layer of C45 steel was enriched with Ni, Mn, Cr and Nb. For alloying the cw CO2 laser beam was used as a power source. Cavitation behaviour of produced layers was investigated in a rotating disc facility. The results reveal different susceptibility to plastic deformation and strain hardening degree of surface in the early stage of cavitation erosion.

Abstract: This work presents investigations of relative cavitation resistance of carbon steel (C45) at the initial stage of erosion, after melting its surface by 6 kW CO2 laser beam. The research work was carried out on the rotating disk facility. Three areas were determined on the surface of investigated sample. Each area was eroded with different intensity. The procedures were elaborated for calculation of resistance of processed surface to plastic deformation under cavitation loading and of relative intensity of cavitation using image analysis of monochromatic picture of eroded surface. The results indicate that increase of cavitation loading intensity results in decrease of relative cavitation resistance.