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AbstractThe purpose of the experiment was to study the influence of the laser beam in pulse mode on metallic foils in order to obtain a spot weld. The welding process was carried out using the overlap weld method, using spot welds in various quantities. The Nd - YAG BLS 720 pulsed laser was used to conduct the experiment. The impact of the number of spot welds on the value of force needed to break the sample was examined. A number of measurements were carried out to determine the best process parameters. Butt welding and overlap welding were also performed using a continuous weld consisting of spot welds. Weld strength tests were performed to select the most appropriate parameters for the process under consideration.

Laser surface texturing is used more and more often in modern machines for the implementation of variety of purposes such as for example intensification of lubrication, intensification of heat exchange, stimulation of microfluidics, increasing the chemical activity of the surface. Owing to the development of technologies using a concentrated energy flux, including laser microprocessing, it has become feasible. The present paper concentrates on the selection of parameters of laser microprocessing with picosecond pulses so as to obtain the highest efficiency and accuracy of the execution of a single texture element.Keywords: laser microprocessing, laser surface texturing (LST), laser ablation, ultrashort pulses W nowoczesnych maszynach dla realizacji różnych celów m.in. takich jak przykładowo intensyfikacja smarowana, intensyfikacja wymiany ciepła, stymulowanie mikroprzepływów, zwiększenie aktywności chemicznej powierzchni; coraz częściej stosuje się teksturowanie powierzchni. Stało się to możliwe dzięki rozwojowi technologii wykorzystujących skoncentrowany strumień energii, do których należy mikroobróbka laserowa. Tematyka opracowania koncentruje się na analizie parametrów mikroobróbki laserowej impulsami pikosekundowymi w celu osiągnięcia jak największej wydajności i dokładności wykonania pojedynczego elementu tekstury.

This article presents some results of laser processing of materials, used for the construction of microsystems and micro-sensors, e.g. Si, Al2O3 and zirconia ceramics. The necessity of faithful reproducing the geometry and dimensions in the micro-scale puts specific requirements for laser machining process. Laser micro-technologies must be conducted under conditions which ensure the perfect guidance of a well-focused laser beam, scanning at a suitable speed, and the laser pulse duration with proper repetition frequency. The amount of absorbed energy depends on wavelength of laser radiation and kind of material, which also influence on this process. All these conditions should take into account the need to maintain a small heat affected zone (HAZ). This guarantees keeping the true reproduction of micro-shapes and cutting edges with a different angle of lines even in micro-scale details. The present work confirms the possibility of using laser technology for such applications.

AbstractLaser surface texturing is currently the most developed technique for producing fully reproducible microcavities on the surfaces of machine elements. From the point of view of texture technology, an important aspect is the proper selection of process parameters to obtain texture elements with desirable and repetitive geometries and physicochemical properties. Surface texturing improves mottling and fretting resistance and is also used wherever the adhesion properties of surface layers (printing techniques, bonding materials, biological and chemical activity, coatings, etc.) are important. The article shows the possibility of applying statistical functions to the selection of appropriate machining parameters to obtain microgeometry useful in the application of textured surfaces [1].