STUDIES OF PROCESSES OF THE PRECURSOR FORMATION FOR PRODUCTION OF CuAlO NANOCERAMICS AT THE EFFECT OF DOUBLE LASER PULSES ON AD1 AND M2 ALLOYS IN THE AIR ATMOSPHERE

Проведено исследование процессов образования смешанных нанопорошков Al, оксидов меди и алюминия, прекурсоров для получения нанокерамик типа CuAlO и CuAlO при воздействии сдвоенных лазерных импульсов энергией 53 мДж и между импульсным интервалом 10 мкс на мишень, состоящую из пластинок алюминия марки АД1 и меди марки М2, склеенных между собой и помещенную в закрытую стеклянную прямоугольную кювету. Установлено, что последовательное воздействие серий сдвоенных лазерных на мишень из алюминия, а затем на мишень из меди приводит к многократному увеличению выхода субоксидов AlO, ионов и атомов алюминия и меди в лазерном факеле, направляемом на подложку, при напылении пленок, по сравнению с воздействием одиночными лазерными импульсами. Изучены процессы, происходящие на поверхности подложки при напылении пленок. Показана возможность получения прекурсоров для получения нанокерамик типа CuAlO и CuAlO. A study of formation of mixed Al nanopowders, copper and aluminum oxides, and precursors for production of CuAlO and CuAlO nanoceramics under the influence of double laser pulses with energy of 53 mJ and the interpulse interval of 10 microseconds on a target consisting of plates of aluminum grade AD1 and copper grade M2, 0,4 mm thick, glued together and placed in a closed rectangular glass cuvette. It is found that the successive exposure of a series of double laser beams to an aluminum target and then to a copper target leads to a multiple increase in the yield of AlO suboxides, aluminum and copper ions and atoms in the laser torch, compared with the exposure to single laser pulses. To better understand the hidden mechanisms of this dependence, we study the processes occurring both on the surface and in the near-surface laser plasma inside the resulting microchannel when the target is broken by a series of single and double laser pulses. The possibility of obtaining precursors for the production of nanoceramics such as CuAlO, CuAlO is shown.

RESEARCH OF AlO и Al NANOPOWDER FORMATION PROCESSES IN PLASMA UNDER THE INFLUENCE OF DEFOCUSED DUAL LASER PULSES ON ALUMINUM IN THE AIR ATMOSPHERE

Изучено влияние величины и типа расфокусировки сдвоенных лазерных импульсов на целенаправленное формирование компонентного и зарядового состава лазерной плазмы при воздействии сдвоенных лазерных импульсов на мишень из алюминиевого сплава АД1 (спектрометр LSS-1). Показано, что при расфокусировке более +1 мм интенсивность линии ионов Al III увеличивается в несколько раз в сравнении с нулевой расфокусировкой, интенсивность линий ионов Al II, N II также более менее монотонно увеличивается. Одновременно с этим интенсивность полос AlO практически становится равным нулю. При значении величины расфокусировки 1 мм проведены исследование процессов образования смешанных нанопорошков AlO и Al при воздействии последовательных серий сдвоенных лазерных импульсов энергией 53 мДж и меж-импульсным интервалом 10 мкс на алюминиевую мишень, помещенную в закрытую стеклянную прямоугольную кювету. Размер первичных частиц AlOоцененный с помощью электронной микроскопии высокого разрешения, преимущественно составил 30 - 40 нм, а Al - 45 - 60 нм. Частицы собраны в агломераты. The influence of the magnitude and type of defocusing of twin laser pulses on the purposeful formation of the component and charge composition of laser plasma under the influence of twin laser pulses on a target made of aluminum alloy AD1 (LSS-1 spectrometer) has been studied. It is shown that when defocusing is more than 1 mm, the intensity of the ion line Al III increases several times in comparison with zero defocusing, the intensity of the ion lines Al II, N II also increases more or less monotonously. At the same time, the intensity of the bands AlO practically becomes zero. At the 1 mm defocusing value, the processes of formation of mixed nanopowders were studied and, under the influence of successive series of double laser pulses with the energy of 53 mJ and the inter-pulse interval of the iss on an aluminum target placed in a closed rectangular glass cuvette, the size of primary Al Oparticles estimated using high-resolution electron microscopy was mainly 30 - 40 nm, and Al -45 - 60 nm. The particles are collected into agglomerates.

Simulation of a Group Impact on a Heterogeneous Target of Finite Thickness

Numerical simulation of the processes of high-speed loading of homogeneous and heteroge- neous targets by single projectiles, as well as by a group of projectiles with the same parameters in mass and momentum, has been carried out. Based on a comparison of the numerical simulation results for loading targets with different sets of projectiles, it is found that a projectile in the form of a ring knocks out the maximum hole in the target in terms of geometric dimensions, while a set of seven small disks removes the maximum mass from the target. The ring impact forms a continuous spall plate, which outruns the cloud of fragments of the destroyed material. Adding more than 5% of ceramics to the aluminum target volume does not allow the projectiles to penetrate through

Ion current optimization in a magnetron with tunable magnetic field configuration

The response of the ion current in the substrate region to the magnetic system configuration of a circular magnetron was studied during direct current sputtering of aluminum target. The unbalancing degree induced by changing of magnets’ positions was modelled with finite element methods. The ion saturation current in the substrate region showed more than twofold variation with unbalancing degree in the range 0.6–1.2. The dependence was non-monotonic, and the system was optimized to maximize the substrate ion current. The Langmuir probe diagnostics showed plasma density ~ 1016 m−3 in the optimized magnetic configuration.

Study on impulse and ablation of aluminum irradiated by millimeter spot of short pulse laser

Aluminum is a high performance working medium for laser ablation micro propulsion. In order to study the propulsion performance and ablation of aluminum under millimeter light spot irradiation, a short pulse Nd: YAG laser with wavelength of 1064nm and pulse width of 8NS was used to irradiate aluminum target in atmosphere. The impulse, the impulse coupling coefficient and the ablation morphology of the aluminum target produced by 6 kinds of millimeter-level light spots are measured. The experimental results show that when the spot diameter reaches 6-7mm, the increasing trend of impulse and impulse coupling coefficient of aluminum target with the increase of laser energy slows down; A large number of ablation products began to accumulate on the surface of the target pit.

3-D aluminum nanostructure with microhole array synthesized by femtosecond laser radiation for enhanced light extinction

This article presents 3-D aluminum micro-nanostructures for enhanced light absorption. Periodic microhole arrays were created by firing a train of femtosecond laser pulses at megahertz pulse frequency onto the surface of an aluminum target at ambient conditions. The laser trains ablated the target surface and created microholes leading to the generation of deposited nanostructures inside and around the microholes. These micro-nanostructures showed enhanced light absorption, which is attributed to surface plasmonics induced by the generation of both nano- and microstructures. These micro-nanostructures may be promising for solar cell applications.

3-D aluminum nanostructure with microhole array synthesized by femtosecond laser radiation for enhanced light extinction

This article presents 3-D aluminum micro-nanostructures for enhanced light absorption. Periodic microhole arrays were created by firing a train of femtosecond laser pulses at megahertz pulse frequency onto the surface of an aluminum target at ambient conditions. The laser trains ablated the target surface and created microholes leading to the generation of deposited nanostructures inside and around the microholes. These micro-nanostructures showed enhanced light absorption, which is attributed to surface plasmonics induced by the generation of both nano- and microstructures. These micro-nanostructures may be promising for solar cell applications.

Modeling of shock-wave processes in aluminum under the action of a short laser pulse

A hydrodynamic model of shock-wave processes in a material under the action of a short high-intensity laser pulse is considered. The simulation is carried out for the case of an aluminum target 90 μm thick, irradiated by a laser pulse with a duration of 70 ps and a maximum intensity of 14.7 TW/cm2. In the corresponding laboratory experiment, on the rear side of the target after irradiation, a spall of a part of the material is recorded at a depth of 10±1 μm. Calculation of the time dependence of the pressure and density of aluminum in the spall plane makes it possible to determine the tensile strength of aluminum at a high strain rate.