Now showing 1 - 8 of 8
  • Publication
    LASER ABLATION OF PAINT COATINGS IN INDUSTRY
    A comparison is made between the laser and sandblasting methods for removing paint from industrial facilities. The advantages of laser ablation are discussed. The possibilities of laser paint removal systems - stationary and moving - are shown. The main factors influencing the laser ablation process and the indicators that determine the quality of the obtained surface are systematized. Researchers' publications on this technological process are analyzed.
  • Publication
    RESEARCH OF LASER MARKING AND ENGRAVING ON BRASS ALLOY 260
    Brass Alloy 260 is widely used in mechanical engineering (odometer contacts, radiator cores), electrical engineering (electrical connectors, screw shells), plumbing (bathroom fixtures), consumers (watch parts, buttons, lamps) etc. The paper presents an analysis of the laser marking and engraving process. The ability Rofin powerline f20 laser system to engrave on Brass Alloy 260 is described. Recommendations are given on choosing the right parameters for laser marking and engraving of Brass Alloy 260 products.
    Scopus© Citations 1
  • Publication
    Investigation of Surface Structure in the Laser Marking Process as a Function of Speed and Raster Step
    In this research, an experiment was conducted to change the technological properties of the surface by laser marking. The influence of the speed v of 50 mm/s, 75 mm/s and 100 mm/s and the raster step Δx from 20 µm to 80 µm at a constant average power P = 19.2 W and pulse duration τ = 4 ns was investigated. These parameters during the laser marking of AISI 304L steel have a significant change in microhardness and surface roughness. High hardness was found to be achieved at higher powers and small pitch. Analysis of the results showed that as the raster step increases, the roughness of the marked sample decreases. The effect of linear energy density and overlap factor on the process was also investigated. The microhardness of the machined surfaces increases with an increase in the linear energy density and the overlap coefficient, in the first case the dependence is almost linear, and in the second - nonlinear. Varying the marking speed and raster pitch in laser surface texturing of AISI 304L steel has a significant effect on the surface hardness and roughness, changing HV from 260 HV to 766.5 HV and Ra from 1.75 µm to 4.3 µm, respectively, which are the subject of the present analysis. research.
  • Publication
    RESEARCHING THE PROCESS OF LASER STRUCTURING OF THE SURFACE OF ALUMINUM
    (2023-06-13)
    Kevins Bulavskis
    ;
    Emil Yankov
    ;
    ;
    In this scientific study, the ability to modify the surface using nanosecond 1064 nm fiber laser by controlling the speed and scanning line step in the marking process was demonstrated. An experimental matrix for laser marking was developed, consisting of 8 columns for marking line step and 5 rows for marking speed. The laser marked surfaces were measured using a laser scanning microscope and compared with the surface as supplied. From the obtained deviations of roughness Ra, Rz and Rq as a function of marking speed and marking line step, graphical dependencies were constructed for comparative analysis. The modified roughness is also compared with the roughness as supplied. Within this research the effect of laser treatment on the hydrophilicity/hydrophobicity of the surface was studied as well. Plots of dependences of the contact angle CA, the marking line step Δx and the overlap coefficient Ksoc are plotted.
  • Publication
    USE OF CO2 LASER FOR MARKING AND CLEARING OF TEXTILE MATERIALS FOR MANUFACTURE OF MILITARY EQUIPMENT
    (2019-06-19) ;
    Jordan Shterev Ivanov
    ;
    Stelena Dimitrova Lilyanova
    ;
    ;
    Nikolay Todorov Dolchinkov
    In the last decades, a large application has been found by lasers in marking and cutting on textiles, plexiglass, wood, metals and other materials. These items apply to both the military and the economy of the countries of the world. A group of Bulgarian students from the National Military University Vasil Levski, led by Dr. Nikolay Dolchinkov, conducted a research with a group of TAR under the leadership of Prof. Lubomir Lazov at the Laser Center in Rezekne at the end of 2018. The report shows the achieved results and the relevant analyzes. Graphically and tabularly, the dependence of the depth of the markings and the cut-off of the power and speed of the used CO2 laser are presented.
    Scopus© Citations 1
  • Publication
    OPTIMIZATION OF CO2 LASER PARAMETERS FOR WOOD CUTTIOPTIMIZATION OF CO2 LASER PARAMETERS FOR WOOD CUTTING
    (2017-06-14)
    Hristina Deneva
    ;
    Janis Valiniks
    ;
    ;
    Dainis Klavins
    ;
    Pavels Narica
    ;
    By taking advantage of the best characteristics of wood, modern production methods can offer hard wearing and ecological solutions in industrial construction, house building, machinery construction, furniture manufacturing, transport and many other industries. Laser cutting process is an alternative choice to prepare the final shape of wood parts. Materials like wood have good laser light absorption of wavelength 10600 nm. In this paper a CO2 laser system with a maximum continuous-wave output power of 150 W is described and used in studying laser cutting process of wood materials. Cut depth is evaluated with variation of values of laser power and cutting speed. Additionally, optimal values of parameters for laser cutting of different wood plate thicknesses are determined and graphs are created showing the results.
    Scopus© Citations 1
  • Publication
    Modification of Aluminum 1050 and 2219 Alloys Using CuBr Nanosecond Laser for Hydrophobic and Hydrophilic Properties
    This study investigates the use of a CuBr vapor nanosecond laser with a 510 nm/578.2 nm wavelength for the surface treatment of 1050 aluminum and 2219 aluminum alloys. Laser-induced periodic surface structuring was used to optimize processing parameters to achieve hydrophobic and hydrophilic properties on the surface. The wetting properties were measured and the roughness results (Ra, Rz, Rq) evaluated. Prior to and after laser treatment, surface wetting and roughness changes were investigated. The wetting study showed that the maximum contact angle between a droplet of deionized water and the treated surface can be reached between more than 140 degrees and less than 10 degrees, which, respectively, is a superhydrophobic and superhydrophilic surface. Compared with the untreated surface, wetting increased by more than 2 times and decreased by more than 8 times. Overall, experiments show the dependence of wetting properties on laser input parameters such as scan speed and scan line distance with different delivered energy amounts. This study demonstrates the possibility of laser parameter optimizations which do not require auxiliary gases and additional processing of the resulting surfaces to obtain different wetting properties on the surface. The findings described in this article suggest that the CuBr laser surface treatment method is a promising method for industrial applications where surfaces with special wetting and roughness properties are required, for example, the laser marking of the serial number of parts used in wet environments such as aerospace, shipbuilding, and defense industries.
  • Publication
    Effect of Laser Marking Speed, Power and Pitch on Hardness and Roughness of Aisi 304l
    In this study, an experiment was conducted to change the technological properties of the surface by infra-red laser marking. The influence of power, speed and raster step was investigated. These parameters during laser marking of AISI 304L steel have a significant change on the microhardness and surface roughness. It was found that high stiffness is achieved at higher powers and small pitch. An analysis of the results showed that as the raster step increases, the roughness of the marked sample decreases. The influence of linear energy density and overlap factor on the process was also investigated. The microhardness of the treated surfaces increases with an increase in the linear energy density and the overlap coefficient, and in the first case the dependence is almost linear, and in the second - non-linear.