OBTAINING WEAR-RESISTANT COATINGS ON COPPER ALLOYS UNDER SHS CONDITIONS

Obtaining wear-resistant coatings on copper alloys under shs conditions

INVESTIGATION OF THE FEATURES OF THE FORMATION OF ALUMINIZED COATINGS UNDER THE CONDITIONS OF SHS

Investigation of the features of formation of aluminized coatings under the conditions of SHS

Modification of the surface of copper alloys with aluminum in the conditions of self-propagating high-temperature synthesis

The influence of the technological parameters of the SHS process (temperature, holding time and alloying of B, Cr, Ti) on the corrosion resistance of brass with a surface alite layer, which effectively resists β-radiation, was studied. The research was carried out in 30% aqueous solutions of HNO₃, HCl, H₂SO₄. Aluminized coatings doped with silicon, which are obtained under optimal parameters, have 1.7-2.1 times higher corrosion resistance than doped B and Ti. Alloyed coatings have phases CuSi, CuAl, CuAl₂, CuTi, Ti₂Cu₃, CuCr, Cu₃Al, Cu₂Al, Al₃Si, and α-phase doped with Cr, Al, Si, B, Ti. When tested in a 30% aqueous solution of nitric acid, the coating doped with titanium and silicon shows a weight loss of 32 and 37 g/m², respectively.Досліджено вплив технологічних параметрів СВС-процесу (температури, часу витримки та легування B, Cr, Ті) на корозійну стійкість латуні з поверхневим алітованим шаром, який ефективно протистоїть β-випромінюванню. Дослідження проводили в 30% водяних розчинах HNO₃, HCl, H₂SO₄. Алітовані покриття, леговані кремнієм, які отримані при оптимальних параметрах, мають у 1,7–2,1 рази вищу корозійну стійкість, ніж леговані B та Ti. Алітовані покриття мають фази: CuSi, CuAl, CuAl₂, CuTi, Ti₂Cu₃, CuCr, Cu₃Al, Cu₂Al, Al₃Si та α-фазу, леговану Cr, Al, Si, B, Ti. При випробуванні у 30% водному розчині HNO3 покриття, леговані титаном та кремнієм, мають втрату ваги відповідно 32 та 37 г/м²

The role of energy management in the agricultural sector: key prerequisites and impacts

Received: January 30th, 2023 ; Accepted: April 8th, 2023 ; Published: May 3rd , 2023 ; Correspondence: [email protected] is one of the most energy-consuming sectors in the EU’s economy. Implementing sustainable agriculture to reduce GHG emissions and increase energy efficiency through energy management is a crucial strategy to tackle climate change. In this paper, the role of energy management in the agricultural sector is studied, and experiences from Europe and the world have been considered. Literature analysis regarding the chosen topic has been conducted, including the methodology of energy management plan development and its implementation in the case study of Latvia. Data from Latvia’s agricultural and other sectors have been analysed and compared. Latvia’s Inventory Report regarding GHG emissions in the agricultural sector was reviewed, and all emission sources in the agricultural sector were highlighted. The primary purpose of the study is to find out if energy management were introduced in an agricultural company, what would be the potential GHG emission, energy savings and additional advantages. Two companies working in Latvia were surveyed, and potential emission and energy consumption reduction measures in agriculture that would be applied to companies were developed. The research showed that by implementing the basic principles of energy management, it would be possible to reduce the average energy consumption by 17%. If measures are applied to reduce GHG emissions from agricultural companies, the average emissions would be reduced by 43%

Research of special limits during heat treatment of materials in the two-phase region under supercritical temperature influence

The results of the research on establishing the dependence of the coercive force (Нs) on special boundaries in a low-carbon alloy are given. Annealing at a temperature of 900 °С with a holding time of 1 to 3 h leads to an increase in the number of special boundaries from 22.7 to 37.17% and to an increase in magnetic permeability and, accordingly, a decrease in the coercive force from 1.60 to 1.24 A/cm. When the load is axially stretched, the coercive force changes. The initial stage of plastic deformation is most sensitive to the growth of coercive force, which allows us to identify areas in which local plastic deformation has occurred, which indicates a significant decrease in the operational characteristics of parts.Наведено результати дослідження по встановленню залежності величини коерцитивної сили (Нс) на спеціальні границі в низьковуглецевому сплаві. Відпал при температурі 900 °С з витримкою від 1 до 3 год призводить до збільшення кількості спеціальних границь з 22,7 до 37,17% та до збільшення магнітної проникності й відповідно зниження величини коерцитивної сили з 1,60 до 1,24 А/см. При осьовому розтягуванні навантаження змінюється коерцитивна сила. Початкова стадія пластичної деформації найбільш чутлива до зростання коерцитивної сили, що дозволяє виявити ділянки, в яких сталася локальна пластична деформація, що свідчить про значне зниження експлуатаційних характеристик деталей

Thermoelectric behavior of BaZr0.9Y0.1O3−d proton conducting electrolyte

BaZr0.9Y0.1O3-δ (BZY10), a promising proton conducting material, exhibits p-type conduction under oxidative conditions. Holes in BZY10 are of the small polaron type. However, there is no clear understanding at which places in the lattice they are localized. The main objectives of this work were, therefore, to discuss the nature of electronic defects in BZY10 on the basis of the combined measurements of the thermo-EMF and conductivity. Total electrical conductivity and Seebeck coefficient of BZY10 were simultaneously studied depending on partial pressures of oxygen (pO2), water (pH2O) and temperature (T). The model equation for total conductivity and Seebeck coefficient derived on the basis of the proposed defect chemical approach was successfully fitted to the experimental data. Transference numbers of all the charge carriers in BZY10 were calculated. The heat of transport of oxide ions was found to be about one half the activation energy of their mobility, while that of protons was almost equal to the activation energy of their mobility. The results of the Seebeck coefficient modeling indicate that cation impurities, rather than oxygen sites, should be considered as a place of hole localization. © 2019 by the authors. Licensee MDPI, Basel, Switzerland.Russian Science Foundation, RSF: 18-73-00022Funding: This work was supported by the Russian Science Foundation (project No. 18-73-00022

PrBaCo 2 O 6−δ -Ce 0.8 Sm 0.2 O 1.9 composite cathodes for intermediate-temperature solid oxide fuel cells: Stability and cation interdiffusion

The single-phase oxide PrBaCo 2 O 6−δ and composites (100 − y)PrBaCo 2 O 6−δ -yCe 0.8 Sm 0.2 O 1.9 (y = 10–30 wt.%) were investigated as cathode materials for intermediate-temperature solid oxide fuel cells. The chemical compatibility, cation interdiffusion, thermal expansion and dc conductivity were studied. As a result, strong interdiffusion of Pr and Sm was found between PrBaCo 2 O 6−δ and Ce 0.8 Sm 0.2 O 1.9 . This leads to only insignificantly decreasing thermal expansion coefficient of composite with increasing fraction of Ce 0.8 Sm 0.2 O 1.9 and, thus, mixing PrBaCo 2 O 6−δ with Ce 0.8 Sm 0.2 O 1.9 does not improve thermal expansion behavior of the cathode material. Moreover, formation of poorly-conducting BaCeO 3 , caused by chemical interaction between the double perovskite and doped ceria, was shown to lead to pronounced drop in the electrical conductivity of the composite cathode material with increasing Ce 0.8 Sm 0.2 O 1.9 content. © 2019 by the authors