This article provides an overview of the precision laser cutting of thin-walled materials with a focus on its application in manufacturing medical stents. The study discusses the advantages of femtosecond laser technology, which provides high precision and minimal thermal effects required to maintain the integrity of delicate materials used in stent manufacturing. The article also highlights the selection of laser parameters to optimize cutting quality and minimize defects. Additionally, future prospects for laser cutting in the medical field are considered, including improvements in efficiency and exploration of novel materials.

Thin films of copper and brass were deposited on polyimide substrate by using pulsed laser deposition (PLD) method. The target materials selected for this study were Copper Ml and Brass LS59-1. The structures of these materials were analyzed using a metallographic microscope 1350 (ADF, China), and their chemical compositions were examined using an energy dispersive microanalysis (Bruker) to control their chemical purity. Film deposition was made by excimer $\mathbf{KrF}$ laser (wavelength λ = 248 nm, pulse duration $\tau=20$ ns, energy density $\mathrm{W}=5\mathrm{J}/\text{cm}^{2})$. The average value of the pressure in the working chamber during the experiment was $\mathrm{P}=10^{-6}$ Torr. Obtained metal films were studied by using TM4000 Plus scanning electron microscope (Hitachi, Japan). Investigated structure contained imperfections, such as droplects and pores. The reasons which can help to understand and explain their occurrence are given. A small literature review was made to underline the ways of droplet reduction.

ntroduction. Diagnosis and determination of treatment tactics in patients with urolithiasis are based on determining the causes of lithogenesis. At the moment, the standard of examination in patients at high risk of recurrence of urolithiasis is the detection of metabolic disorders based on the results of a biochemical analysis of blood and daily urine, as well as an assessment of the chemical composition of the urinary stone. The violations determined using this approach are a manifestation of the physico-chemical processes of stone formation, the assessment of which is currently practically not performed by urologists, due to the lack of simple diagnostic methods and tools. Materials and methods. The review was conducted on the basis of data published in PubMed databases (https://www.ncbi.nlm.nih.gov/pubmed) and Scientific Electronic Library еLibrary.ru (https://elibrary.ru/), and was limited only to articles in scientific peer-reviewed journals. The search was devoted to the study of the crystal-forming activity of urine, factors affecting the lithogenic properties of urine, as well as methods for assessing the risk of stone formation in the most common metabolic types of urolithiasis. We found 189 sources no older than 10 years (published after 2012) that were relevant to the topic of the review. Conference abstracts, short messages, duplicate publications wereexcluded from them. After that, based on the relevance of the data, reliability of sources, impact factors of journals and the sequence of presentation of the material in the manuscript, 41 articles were selected directly for citation in the review. Also, when writing the review, original articles published before 2012 were used. Results. The analyzed literature sources demonstrated a large number of methods for determining the crystallization properties of urine. However, none of them, in view of the complexity, as well as the ambiguity of the results obtained, have not been widely introduced into clinical practice. In view of this, it is required to develop a simple and informative method for diagnosing the crystal-forming properties of urine, which will increase the percentage of non-reactive urolithiasis. Conclusions. The methods available to doctors for determining the crystal-forming properties of urine are extremely laborious. The development of an easy-to-use and sufficiently accurate real-time determination of the crystallization and anti-crystallization properties of urine, will significantly improve the diagnosis, treatment and metaphylaxis of urolithiasis.

Films based on molybdenum disulfide deposited on ceramic substrates are of practical interest as optical coatings. Such coatings can be used in different instruments for measuring optical radiation energy parameters. The promise of the MoS 2 -based films on AlN substrates is based on their special optical properties and radiation resistance. In this paper is used an excimer KrF laser with a pulse duration of 30 ns, the wavelength of 248 nm and the target incidence angle of 45° to fabricate thin films. The experiments were carried out by varying the substrate temperature and chamber pressure. For the coatings deposited on textured substrates, the spectral reflectivity characteristic and the resistance to laser radiation under variable power density were measured. The study results revealed the main effects of the PLD method process parameters and parameters of the ceramic substrates on the optical properties and radiation resistance of the obtained coatings. The study determined the wavelength ranges of minimum reflection and threshold power density values.

In this article, we report on experimental studies of the influence of several laser radiation parameters, such as the duration of the laser pulse, the radiation wavelength, and the pulse energy, on the efficiency of the destruction of urinary calculi. The study used a laser lithotripter based on a fiber Tm laser generating at a wavelength of 1940 nm with pulses with a duration of about 1800 μs and pulse energy of up to 6 J, as well as a femtosecond solid-state Yb laser generating at a wavelength of 1032 nm with a pulse duration of about 250 fs and pulse energy of up to 400 μJ. A comparative analysis was carried out according to such criteria as the productivity of lasers when removing a unit mass of images and the amount of sample displacement resulting from the retropulsion effect. The results obtained in this work demonstrated that the femtosecond laser loses approximately two times its efficiency in terms of sample material removal. However, this shows the absolute advantage of the photoionization mechanism of femtosecond laser ablation in the study of retropulsion and thermal heating, which were completely absent in this case.

Thermoelectric materials in the form of thin films are used to create a wide variety of sensors and devices. The efficiency of these devices depends on the quality and efficiency of the thermoelectric materials obtained in the form of thin films. Earlier, we demonstrated that it is possible to obtain high-performance Bi2Te3Sb1.5 films less than 1 μm thick on polyimide substrates by using the PLD method, and determined optimal growth conditions. In the current work, the relationship between growth conditions and droplet fraction on the surface, microstructure, grain size, film thickness and chemical composition was studied. A power factor of 5.25 μW/cm×K2 was achieved with the reduction of droplet fraction on the film surface to 0.57%. The dependencies of the film thickness were studied, and the effect of the thickness on the efficiency of the material is shown. The general trend in the growth dynamics for Bi2Te3Sb1.5 films we obtained is the reduction of crystalline size with Pressure-Temperature (PT) criterion. The results of our work also show the possibility of a significant reduction of droplet phase with simultaneous management of crystalline features and thermoelectric efficiency of Bi2Te3Sb1.5 films grown on polyimide substrates by varying growth conditions.

The influence of the growth conditions of diamond-like coatings formed by pulsed laser deposition on their tribological properties is studied. A relatively low (about 15%) content of sp3 phases is found to cause a 20% reduction in the surface wettability and a simultaneous 15% increase in the friction wear resistance. These results can be used to increase the efficiency of brazed plate heat exchangers.

Diamond-like carbon coatings are used for surface hardening, reducing friction coefficient, biological passivation, and reducing sublimation in cosmic environments. Current work describes technological peculiarities of diamond-like films growth obtained with pulsed laser deposition method and their influence on the morphology and sp2/sp3 carbon phase ratio.

The peculiarities of obtaining p -Bi 0.5 Sb 1.5 Te 3 and n -Bi 2 Te 2.7 Se 0.3 thin thermoelectric films with a thickness of about 300 nm grown on a polyimide substrate by the pulsed-laser-deposition method are reported. The influence of the growth temperature, pressure and target-to-substrate distance on the film’s thermoelectric properties is investigated. Thermoelectric p - and n -type films exhibit a high Seebeck coefficient of 220 and –200 μV/K and low electrical power factors of 9.7 and 5.0 μW/(cm K 2 ) respectively due to the relatively high electrical resistances of the films.

Abstract The peculiarities of obtaining p -Bi_0.5Sb_1.5Te_3 and n -Bi_2Te_2.7Se_0.3 thin thermoelectric films with a thickness of about 300 nm grown on a polyimide substrate by the pulsed-laser-deposition method are reported. The influence of the growth temperature, pressure and target-to-substrate distance on the film’s thermoelectric properties is investigated. Thermoelectric p - and n -type films exhibit a high Seebeck coefficient of 220 and –200 μV/K and low electrical power factors of 9.7 and 5.0 μW/(cm K^2) respectively due to the relatively high electrical resistances of the films.

The deposition of contaminants onto spacecraft surfaces may have a negative impact and deposition rate is related to insolation cycles. The present work is focused on the development of a hybrid sensor of the deposited mass based on the piezoelectric effect and the energy parameters of radiation using thermoelectric principles. The design calculation of the thermoelectric part showed the possibility of providing the required responsivity with a diameter of the absorption area of 10 mm and 35 thermopiles using the combination of p-Bi0.5Sb1.5Te3 and n-Bi2Te2.7Se0.3 thin films prepared by pulsed laser deposition method.

Correlation between hardness and optical properties of diamond-like carbon (DLC) coatings is considered. Various methods for the characterization of mechanical, chemical and optical properties of DLC coatings are used; however, some of these methods are destructive, and others are non-destructive. It was found that optical properties of DLC coatings are proportional to their hardness. The mathematical expression that allows to calculate the hardness of a DLC coating according to its refractive index is proposed. Therefore, it is possible to avoid the use of destructive methods (such as nano-indentation technique) to characterize DLC coatings.

Thin film technologies are widely used in science and industry and have a critical value for optics and electronics. Special properties of thin films are related to their thickness, usually ranging between 1 nm and 1 um. Measuring such a thickness is a challenging task, always concomitant with the stage of technology development. When using witness samples and specimen control groups, destructive methods can be employed to measure the thickness of the deposited layers. An analysis of the most commonly used destructive methods of measuring the thickness of thin films is conducted, the results of which can be used for selecting a suitable method when planning corresponding experiments. This work describes theoretical and practical considerations of using bevel cut method, spherical cut method, atomic force microscopy and stylus profilometry for measuring thin film thickness.

Radiation thermopiles are basic structures for sensors used for measuring energy parameters of different radiation with wavelength from 0.1 to 100 mcm. Current work describes features of using p-Bi0.5Sb1.5Te3 and n-Bi2Te2.7Se0.3 thin film thermopiles obtained with pulsed laser deposition method on different substrates. Thermal modeling and experimental research reveal the possibility of achieving responsivity of 1 V/W and time constant of 10 seconds with the use of polyimide substrates and absorption zone of 16 mm in diameter

The thickness of thin films determines the films’ unique properties, due to which they are widely used in optics and electronics. To measure the thickness of films in the range of 1 nm — 1 mcm during film deposition or on a finished product, it is important that non-destructive measurement methods should be used. An analysis of the most commonly used non-destructive methods for measuring and controlling the thickness of thin films is performed, with a possibility of in situ control of the technological process as well as for testing of finished products. This work describes theoretical and practical considerations of using reflection high-energy electron diffraction, piezoelectricity, interferometry and gravimetric methods for thin film thickness measurements. The results of the study can be used for selecting an optimal method of obtaining thin films when conducting theoretical and applied research.

Radiation thermopiles are structural units of sensors used for measuring the energetic parameters of  radiation  in  the wavelength range from 0.1 to 100 µm. The question of the application potential of p-Bi0.5Sb1.5Te3 and n-Bi2Te2.7Se0.3 films prepared by pulsed laser deposition in radiation thermopiles on different substrates was studied. It is shown by thermophysical calculation and the experimental studies of prototypes that the use of polyimide substrates may provide a responsivity of about 1 V/W for an absorption area 16 mm in diameter (the time constant is about 10 s).