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The conditions of nanopores formation in metallic materials during the pulse-periodic laser action were determined. Laser action on two-component Cu-Zn alloy brass L62 was performed with using a CO 2 laser ROFIN DC 010. Laser processing using pulseperiodic radiation with a pulse frequency in the range of 100Hz to 5000 Hz enables the formation of a stable stress state on the sample surface at a temperature that does not exceed the melting point. The structure, containing open pores that fairly evenly distributed over the area, is formed during laser action to the surface of the metallic material. Branched pores with dendrite structure are also formed. The channel type nanopores with a width of ~100 nm were formed under the chosen temperature-rate conditions, creating a nanoporous network. The formation of such structure is realized due to the creation of vacancies and their coagulation as a result of zinc sublimation from the surface of the material. This creates a concentration gradient and promotes diffusion to the surface of the component with relatively high vapour pressure. Measurement of vibration rate of the samples was performed. It was established that regardless of the external laser exposure frequency, the maximum values of the vibration rates of the forced oscillations of samples occur at almost the same frequencies corresponding to their natural oscillation frequencies, under these conditions, nanoporous structures are formed. Damping device application significantly reduces the vibration rate values. In this case the formation of the nanopores in the metallic material does not occur. It is determined that the intensity of formation nanopores in the studied metallic material depends on its vibration characteristics by laser action. The condition of nanopores formation is the presence of significant vibration of the sample.

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Plastics are more and more frequently applied in the construction of hydraulic components and systems, and recently, in the building of microhydraulic assemblies. The basic unit of the microhydraulic systems is a micropump. It is an object which is quite difficult to design and manufacture, especially when using plastics. The paper is a presentation of challenges that must be met in the process of designing gear pumps, and, at the same time, of the theoretical grounds for the designing of those objects. The challenges include the geometry and the gears, the construction of the pump body, the hydraulics of the pump, and the material—the plastic of which the pump is made. The knowledge on those issues was applied to make and to successfully test a prototype of a micropump.