Now showing 1 - 10 of 15
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Mathematical Model of the Distribution of Laser Pulse Energy

2018, Pavels Narica, Teilāns, Artis, Lazov, Lyubomir, Pavels Cacivkins, Teirumnieks, Edmunds

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INVESTIGATION OF THE ROLE OF CERTAIN FACTORS AFFECTING THE CONTRAST IN LASER MARKING

2011, Lazov, Lyubomir, A. Atanasov, N. Angelov

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RESEARCH OF LASER MARKING AND ENGRAVING ON BRASS ALLOY 260

2019, Dainis Klavins, Lazov, Lyubomir, Antons, Pacejs, Ritvars Rēvalds, Zaicevs, Edgars

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.

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ON THE POSSIBILITY OF MARKING EGGS WITH A CO2 LASER

2021, Pēteris Čeirs, Adijāns, Imants, Lazov, Lyubomir

A number of policies and standards regarding food safety issues and quality management have been established for the food industry. One of these requirements is related to the marking of food products describing the expiration date, content and quality.  The report examines the possibility of using laser technology to mark chicken eggs. The contrast of the laser marking is the main criterion for determining its quality. The study examines the functional dependences of the contrast on the main technological parameters of the marking process: laser output power (7 – 20.3 W) and processing speed (50 - 300 mm/s). As a result of the research, optimal parameters for marking with a technological laser system CO2 have been determined.

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Investigation of the Change in Roughness and Microhardness during Laser Surface Texturing of Copper Samples by Changing the Process Parameters

2023, Risham Singh, Lazov, Lyubomir, Emil Yankov, Nikolay Angelov

The aim of this research is to achieve a high-quality and long-lasting laser marking of ammunition, which is of interest to the defense industry. The study is about the effects of speed, raster pitch and power on the roughness and microhardness of the marked areas of copper samples. The experiments were carried out with a fiber laser and a copper bromide laser—modern lasers widely used in industrial production. Laser power, scan speed and raster step were varied to determine their effects on the resulting microhardness and surface roughness. The lasers operate in different wavelength ranges, with the optical laser operating at 1064 nm in the near-infrared region and the copper bromide laser at 511 nm and 578 nm in the visible region, allowing the influence of wavelengths on the process to be investigated. The roughness and microhardness velocity dependence for three powers and two pulse durations for the fiber laser were obtained from the experimental data. The dependence of roughness and microhardness on the raster step for both types of lasers was also demonstrated.

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METHOD FOR COLOR LASER MARKING PROCESS OPTIMIZATION WITH THE USE OF GENETIC ALGORITHMS

2017, Pavels Narica, Lazov, Lyubomir, Teilāns, Artis, Grabusts, Pēteris, Teirumnieks, Edmunds, Pavels Cacivkins

Optimization of color laser marking process mostly depends on effective identification of optimal values of laser marking parameters. This is a difficult combinatorial optimization problem, which is still essential for companies that use laser marking systems. The study proposes a new approach to the process optimization through the use of genetic algorithms, carrying out preliminary experimental investigation, analyzing the laser marking results, and presenting possible improvements to the current implementation of genetic algorithms.

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Investigation of Surface Structure in the Laser Marking Process as a Function of Speed and Raster Step

2023, Emil Yankov, Lazov, Lyubomir, Teirumnieks, Edmunds, Nikolay Angelov, Adijāns, Imants, Antons, Pacejs

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.

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Mathematical Model of Forecasting Laser Marking Experiment Results

2018, Pavels Narica, Teilāns, Artis, Lazov, Lyubomir, Pavels Cacivkins, Teirumnieks, Edmunds

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LASER HARDENING USE FEATURES ON STEEL C45

2019-01-01, Zaicevs, Edgars, Teirumnieks, N., Lazov, Lyubomir

The paper investigates and describes laser hardening of steels, types of lasers, important parameters of laser hardening, as well as steels that are suitable for laser hardening process. The laser hardening process of steel C45 samples is described, the analysis of the results is described and the result is summarized. The results of the experiments show that laser hardening is capable of meeting the relevant requirements and quality parameters in steel C45 hardening.

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IMPACT OF LASER ON MICROORGANISMS IN THE DIGESTATE

2017, Tretjakova, Rasma, Lazov, Lyubomir, Martinovs, Andris, Samanta Marija Misiņa

At the biogas plant total of 40 digestate samples have been collected and investigated. The microbiological composition of digestate has been analysed before and after laser processing with wavelength λ 445 nm with power 2 - 4 W. Salmonella spp. has not been stated in any of the samples, Escherichia coli and Enterococcus spp. amount does not correspond Eiropean Union regulation R142/2011 requirements in any of the investigated samples; Staphylococcus aureus has been stated in 24 samples out of 40. By decreasing laser scanning speed and increasing power, the total number of microorganism colonies in digestate has decreased.