Now showing 1 - 7 of 7
  • 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
    ANALYSING THE INFLUENCE OF TECHNOLOGICAL PARAMETERS ON THE PROCESS OF LASER MARKING OF SURFACE OF ANODISED ALUMINIUM SAMPLES
    (2023)
    Ļubova Denisova
    ;
    ;
    Emil Yankov
    ;
    The requirements for marking in terms of contrast and durability are constantly increasing. In order to meet all these challenges, it is necessary to carry out research leading to the optimisation and increase in efficiency of the technological process of laser marking. In the case of aluminium, the contrast and durability of the marking depend on the values of the laser marking parameters. In order to determine the optimal laser marking method, experimental studies have been carried out, controlling the power, speed, frequency, pulse duration and line raster step for a specific anodised aluminium. The studies carried out were analysed and subsequently optimized to obtain a contrast marking. A Rofin PowerLine F 20 Varia fiber laser system and aluminium alloy 1050 with anodised surface were used for the research. The surface changes after the laser treatment were analysed using a laser scanning microscope and contrast determination method. The dependence of contrast and roughness on speed, power, frequency and raster step was analysed. Comparative plots of contrast and roughness variations versus laser marking technological parameters were constructed.
  • 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
    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
    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.