Norbert Radek

The article analyzed the problem of cloud defect in metallic paint, caused by grain arrangement during paint application on a structural element. Presents test results of coating system consist of a high solid corrosion protection primer and a two-component topcoat with a metallic gloss effect (RAL 9006) developed in our company. The paint system properties were examined after the conditioning period.

The paper discusses the use of efficient surfaces for heat transfer enhancement during a nucleate boiling heat transfer. Distilled water under ambient pressure was the working fluid in the presented experiment. The application of a brass mesh of 0.63 mm aperture and 0.20 mm wire diameter on the surface of a copper heater led to considerable improvement in the value of heat flux at low temperature differences of a few Kelvin, where the enhancement ratio exceeded 2. Such modified surfaces could be used in the design of more efficient heatn exchangers e.g. in refrigeration systems.

The paper concerns testing Cu−Mo coatings deposited over carbon steel C45, which were then eroded with a laser beam. The analysis involved the measurement of macrogeometry and microhardness of selected areas after laser treatment. The coatings were deposited by means of an ELFA-541 device and they were laser treated with a Nd:YAG laser, the parameters being variable.

The paper discusses fire parameters of individual layers of anti-graffiti coating systems proposed for use in rail transport. Modifications and their effect on flammable properties of these coatings have been described. Performed tests included, first of all, parameters such as lateral spread of flame over the surface and heat emission, whose fulfillment proved the most difficult in the previous studies. For this purpose, polyester putties were tested on an epoxy primer. Then, fire parameters for different anti-graffiti systems containing a swelling layer as an additional protective layer were determined.

This paper discusses the effect of selected parameters of laser welding on mechanical properties of welds. Two parameters were analysed: the welding speed and the laser power. The properties of the material in the fusion zone and the heat affected zone were determined by hardness tests and microscopic analysis. The results indicate welds produced at different welding parameters have similar properties.

The paper presents a study on microstructure and microhardness changes obtained in the spun carbon steel tube after shaping by a laser beam. The surface of a pipe was machined circumferentially using a 1500 W CO2 laser beam at various diameters (distance from the focus). As a result, plastic deformations such as convex and narrowing shape changes were observed. The conducted research, including microhardness measurements, shows that, in comparison to the unprocessed material, the microstructure was significantly changed, both in the convex and narrowed layer.

The article summarizes research on a method used to improve tribological properties. The paper presents possibilities of using laser surface modification by means of EDM. The performed research confirmed that the concentrated laser beam stream can effectively modify the state of the ESD coating layer, WC-Cu and improve their usability. The work aims to assess the properties of coatings after laser treatment, based on the observation of the newly created structure of the material, the measurement of adhesion and microhardness measurement.

The paper presents the issue of boiling heat transfer enhancement with the use of different passive techniques, namely the application of wire mesh coatings, capillary porous layers, pin – fins and laser treatment. Enhanced boiling heat transfer has been described as well as the research data of the authors that deals with microstructural coatings. The conducted experimental tests confirm the possibility of increasing heat fluxes transferred at the same superheat value due to the use of heat transfer enhancing techniques.

The paper is concerned with determining the influence of laser treatment process on the properties of electro spark coatings. The properties were assessed after a laser treatment by analysing microstructure and X-ray diffraction and measuring surface geometric structure and microhardness. The studies were conducted using WC-Cu electrodes produced by powder metallurgy of nanostructural powders. The coatings were deposited by means of the EIL-8A model and they were laser-treated with the Nd:YAG, BLS 720 model.

The paper is concerned with the performance properties of electro-spark deposited coatings. The properties were assessed by analyzing the coating microstructure, X-ray diffraction, microgeometry, microhardness, and corrosion tests. The studies were conducted using WC-Co-Al2O3 electrodes produced by the sintering of powders. The anti-wear coatings were electrospark deposited over C45 carbon steel by means of an EIL-8A. These coatings are likely to be applied in sliding friction pairs and as protective coatings.