bluuebunny/crossref_metadata_2025_split huggingface dataset:
Change in Graphite Carbon Structure of Cast Iron Coatings through Different Spray Flame Situations
Authors: Tsunekawa Y. , Ueno T. , Kozaki T. , Okumiya M. , Ozdemir I. 
Published: September 2022

Abstract
Graphitization behavior of water-atomized cast iron powder at each thermal spraying step, such as droplet flight, droplet impingement and splat layering, was successively examined. Both as-atomized cast iron powder and coatings sprayed with the powder contain no graphite structure owing to their rapid solidification. A short period of pre-annealing at 1173 K allows the formation of graphite structure in the cast iron powder, in which there exist precipitated graphite of 3.58 mass%. The microstructure observation exhibits that pre-existed pores in the as-atomized powder strongly affect the precipitating sites of graphite, that is, mainly inside the individual powder instead of the surface. However, marked reduction in graphite structure occurs to coatings sprayed with the pre-annealed powder because of in-flight burning and dissolution into molten iron. In-process post-annealing at 773 K for 60 s reveals the formation of graphite structure resulted from the decomposition of iron based metastable carbide in splats and coatings sprayed with the as-atomized powder. Chemical analysis demonstrates that graphitization level of post-annealed cast iron coatings is higher than that of coatings sprayed with the pre-annealed powder. Precipitated intersplat graphite structure of 1.68 mass% appears in cast iron coatings when introducing methane as a powder feeding carrier gas which is liable to decompose in plasma flame. The resultant coatings with graphite structure embedded in hard matrix are anticipated to offer superior wear resistance in comparison to centrifugally cast iron containing flaky graphite of 1.76 mass%.
Increase of Process Robustness through Offline Process Control and Noise Factor Influence Reduction
Authors: Bobzin K. , Ernst F. , Zwick J. , Richardt K. , Schmitt R. , Doeren J. 
Published: September 2022

Abstract
After having established an offline process control based on the optical process diagnostic system PFI (Particle Flux Imaging) the process robustness has been increased by experimental identification of the impact of the noise factors „electrode wear“ and „injector wear“ in the APS process. Neural networks were used for implementing a process controller into a GTV APS process control center. In combination with the PFI system a tool was installed in the process center that is able to predict coating quality by analyzing some characteristics of the plasma and the particle plume. The neural network can be trained for all applications and all feedstock materials. An offline controller is instructing the operator through a desktop in order to train the network. The training, that means the monitoring of the process through different parameter setups and its reactions, is generated and executed automatically. Due to the fact that controlling the process parameters cannot influence every aspect of the coating quality, noise factors have to be regarded. For the APS process the electrode wear and the injector wear were identified as the most influencing noise factors. Both were analyzed by means of Design of Experiment (DOE) and long-term monitoring (200 hrs). The samples were characterized by light microscopy and different coating test methods that were chosen with respect to the coatings functions (e.g. wear resistance). The result of this work is a set of parameters that are as robust against both noise factors as possible and that are adapted to certain changes by a neural network process control.
Excellence in Robot Programming for Coating Applications
Authors: Moody D.R. 
Published: September 2022

Abstract
Impressive gains have been made in thermal spray coatings through material development and coating parameter selection. However, it is usually up to shop personnel to develop a robot program to achieve the final coating. Coating programs are often developed using trial and error. Some motion and deposit analysis programs are available. However, they can be costly and require a level of expertise that is generally not available to the typical coating shop. This paper discusses how Microsoft Excel 2003 software can be used as an aid for off-line development of a robot program for coating applications. It starts with a discussion of the Normal Distribution characteristic of thermal spray patterns. It then goes through development of an example using standard Excel function and chart tools for interactive feedback of the coating layers. Also included is a discussion on the use of the program for sensitivity analysis regarding changes to the spray pattern.
A Novel Intelligent Adaptive Temperature Control Approach of Sprayed Coating for APS Process
Authors: Xia W.S. , Zhang H.O. , Wang G.L. 
Published: September 2022

Abstract
Coating damages, such as cracks and spallation, always occur under high temperature gradient and its resulting residual stress level. This is why it is important and necessary to monitor and control the coating temperature during atmospheric plasma spray process. In this paper, a novel measurement approach for substrate and coating temperatures is presented. It is based on IR pyrometery combined to specific robot scanning trajectories in order to avoid harsh environment of spray workshops. The temperature-time evolution was continually detected and recorded during preheating, spraying and cooling stages and the two specific factors, periodic average temperature and standard deviation were adopted to evaluate the temperature variation and the fluctuation of the thermal cycle relevant to one robot scanning cycle based on the statistical method. These two factors were successful in describing the temperature variation during experimental processing sets. Finally, on the basis of experimental results of the influence of Z typed robot spray trajectory parameters, including spray distance, spray velocity and scanning step on coating temperature characterized by the two factors, an intelligent adaptive control of sprayed coating temperature was developed to obtain constant temperature cycles by means of adjusting robot trajectories, cooling, among other considered operating parameters. Excellent control performance is observed.
High Temperature Mechanical Properties of Plasma Sprayed Thin YSZ Deposits
Authors: Syed A.A. , Antou G. , Denoirjean A. 
Published: September 2022

Abstract
Elastic properties of 20 and 40 µm thick deposits of yttria fully stabilized zirconia (YSZ), fabricated by vacuum plasma spraying (VPS) and air plasma spraying (APS) with modified injection system were investigated at room temperature by nanoindentation, and 4 point flexion test and at 800°C by 4 point bend test. The data was correlated with structural analysis of different YSZ deposits. At room temperature, E values of VPS YSZ deposit decreased from 237 ± 6 to 105 ± 5 GPa on increasing nanoindentation load from 1 mN to 450 mN. The results indicated change from intrinsic to defect-dependent E values with increasing load. Despite lower porosity of VPS deposit (6 ± 1%) compared to that of APS (24 ± 1%), E values, measured by flexion test at room temperature and at 800°C, of former were 35 ± 1 and 16 ± 1 and of latter were 55 ± 1 and 18 ± 1 GPa respectively. The interlamellar sliding, parallel to applied load, was considered as prime reason of lower rigidity of deposits.
Effects of Substrate Temperature During Thermal Spray Deposition on Mechanical Properties of Ceramic Coating
Authors: Yamano H. , Takabatake T. , Tani K. 
Published: September 2022

Abstract
Mechanical properties of thermal-sprayed ceramic coatings were investigated. Al2O3 and Y2O3-stabilized ZrO2 (YSZ) coatings were deposited on plate substrates. Stainless steel plates and aluminum plates, of different thermal expansion coefficients, were used as substrates. The coatings were prepared at two different thicknesses. During deposition of each sample, the history of substrate temperature was recorded. Four-point bending tests were carried out, while strains at the coating surface and the substrate surface were measured with strain gages. The apparent Young's modulus of the coating was determined using the composite beam theory. In addition, the rupture strain of the coating was measured by three-point bending test. The relationship between the results of these tests and the temperature of each substrate during deposition is discussed.
Microstructure Control of Thermally Sprayed Co-based Self-fluxing Alloy Coatings by Diffusion Treatment
Authors: Sakata K. , Nakano K. , Miyahara H. , Matsubara Y. , Ogi K. 
Published: September 2022

Abstract
This paper describes microstructure control aimed for wear-resistance improvement of Co-based (Co-Cr-W-B-Si) self-fluxing alloy coating by diffusion treatment. The diffusion treatments of thermally sprayed Co-based self-fluxing alloy coating on steel substrate were carried out at 1370K to 1450K for 600s to 6000s under an Ar gas atmosphere. Microstructural variations of the coating and the interface between the substrate and the coating were investigated in detail. A proper diffusion treatment precipitates two kinds of fine compounds in Co-based matrix. XRD and EPMA analysis revealed these precipitates to be a chromium boride dissolving cobalt and a wolfram boride containing cobalt and chromium. The size of each precipitate became larger with increasing treatment temperature and time. A coating with the proper size borides showed a superior wear-resistance.
Plasma Electrolytic Oxidation of Arc Sprayed Aluminium Coatings
Authors: Pokhmurskii V. , Nykyforchyn G. , Student M. , Klapkiv M. , Karpenko G.V. , Pokhmurska H. , Wielage B. , Grund T. , Wank A. 
Published: September 2022

Abstract
Different post treatment methods such as heat treatment, mechanical processing, sealing, etc. are known to be capable to improve microstructure and exploitation properties of thermal spray coatings. In this work a plasma electrolytic oxidation of aluminium coatings obtained by arc spraying on aluminium and carbon steel substrates is carried out. Microstructure and properties of oxidised layers formed on sprayed coating as well as on bulk material are investigated. Oxidation is performed in electrolyte containing KOH and liquid glass under different process parameters. It is shown that thick uniform oxidised layers can be formed on arc sprayed aluminium coatings as well as on solid material. Distribution of alloying elements and phase composition of obtained layers are investigated. A significant improvement of wear resistance of treated layers in two types of abrasive wear conditions is observed.
Modeling and Experimental Study of the High Pressure Gas Atomization of Liquid Metals
Authors: Allimant A. , Planche M.-P. , Dembinski L. , Coddet C. 
Published: September 2022

Abstract
Liquid metal atomization using a De Laval nozzle has proven its efficiency in producing fine and narrow sized powder. The modeling work of gas dynamics related to nozzle geometry has led to a better understanding of the effects of the processing parameters. During the emptying of the crucible, the decrease in the static height of the melt acts on the metal mass flow rate. An experimental study on the particle size distribution in the cross-section of the spray and its evolution during the process has confirmed the unsteadiness of the process. By establishing a model to fit the gas pressure to the mass flow rate evolution, an almost steady state can be reached for the process. This has brought us to reduce the mean particle size and to improve the narrowness of the as-atomized particle size distribution.
Effect of Laser Irradiation on Micro Structure of Carbide Coatings
Authors: Kuwashima T. , Saitoh T. , Sonoda T. , Suzuki K. , Fujiwara M. 
Published: September 2022

Abstract
In the thermal spraying technique, the process includes some problems such as insufficient cohesive strength between particles in the coating. It is considered that the laser treatment of thermal spray coating will be effective method to improve the coating properties. In this study, an yttrium aluminum garnet (YAG) laser treatment was carried out on the sprayed coating in order to examine the effect of laser beam on the coating properties and post laser treatment method and hybrid spraying method were carried out. Irradiation laser power conditions were 1.5kW, 2.0kW and 2.5kW, and defocus distance conditions were ±0mm, +30mm, +60mm, +90mm, changing the energy density and the traverse speed conditions were 100mm/s, 200mm/s, 300mm/s. In post treatment method the affected region in the Cr3C2-Ni-Cr coating is smaller with increasing traverse speed. Laser energy density affected the microstructure. In the case of defocus distance ±0mm and traverse speed is 100mmm/s there are three different regions, melted region, heat affected region and no affected region in the coating. The micro Vickers hardness of melted region of coatings was lower and heat affected region of coatings was higher than no laser treatment coating. It was considered that with post laser treatment method it was very difficult to treat the coating uniformly. In the blast erosion test, the wear-out rate of hybrid spray coating was lower than that of the HVOF spray coating. It is considered that the improvement of micro Vickers hardness of Cr3C2-Ni-Cr hybrid sprayed coating resulted from the precipitation of fine chrome carbide in the matrix and their strengthening affect cohesive strength between lamella in the coating. In WC-Co hybrid sprayed coating, the improvement of micro Vickers hardness resulted from the porosity decrease. The coating structure was different even in the identical processing condition by the place. The micro Vickers hardness of melted area of coatings was lower and heat affected area of coatings was higher than no laser treatment coating.
Phase Assemblage of Al-Cu-Cr Quasicrystalline Coatings Sprayed by Low Power Plasma
Authors: Fu Y.Q. , Zhou F. , Gao Y. 
Published: September 2022

Abstract
Al-Cu-Cr quasicrystalline (QC) coatings were deposited onto mild steel Q235A substrate by low power plasma spraying. The plasma torch was designed such that the powders can be injected axially (parallel to the axis of the plasma arc) into the region between the anode and cathode, and the carrier gases were transferred to the plasma flame, so the heating efficiency of the powders is greatly increased and the velocity of particles is much higher than an externally-fed powder system. The Al-Cu-Cr QC coatings were sprayed via this new technique at different plasma power (3~7kW) by controlling the secondary plasma gases (H2 and N2) flow or changing the arc current. The results show that, the original powder was mainly composed of a dominant icosahedral quasicrystalline phase I-Al65Cu24Cr11 and a minor monoclinic θ-Al13Cr2. However, besides these two phases, body-centered cubic α- Al69Cu18Cr13, the approximant to quasicrystal I-Al65Cu24Cr11, has been detected in as-sprayed coatings. On the other hand, peak intensity of QC phase I-Al65Cu24Cr11 decreased and that of crystalline phases (θ-Al13Cr2 or α-Al69Cu18Cr13) increased as the plasma power was increased.
Study on Iron Based Arc Spraying Cored Wire with TiC Ceramic Powders
Authors: He D.-Y. , Zhang F.-Y. , Jiang J.-M. , Fu B.-Y. , Li X.-Y. 
Published: September 2022

Abstract
Iron base composite coatings were deposited on mild steel substrates by arc spraying and cored wire with TiC ceramic powders. The abrasive wear resistance properties were examined on the MLS-225 wet sand/rubber wheel tester. The microstructure, phase compositions and worn surface morphologies of the coatings were observed by means of optical, scanning electron microscopy and X-ray diffraction. The results showed that composite coatings with TiC ceramic hard phases were reinforced by the TiC hard particles distributed in the iron-based coating. The average micro hardness of the coatings is about 1137 HV0.1. The coatings have the excellent abrasive wear resistance which is 6 times higher than that of the Q235 mild steel. Wear mechanisms of coatings was mainly micro-ploughing and brittle fracture.
Characterization of ZrO2-based Coatings by Low Pressure Plasma Spraying Under Different Pressures
Authors: Ye Y. , Liu M. , Zhou K.-S. , Yi D.-Q. , Kuang Z.-Q. , Deng C.-G. 
Published: September 2022

Abstract
Low pressure plasma spray (LPPS) technology has exhibited its advantage in deposition of yttria stabilized zirconia (YSZ) coating. The YSZ coatings deposited under different chamber pressures were characterized by XRD and SEM in this paper. Preliminary results showed that as-sprayed coatings contained partially-melted zone, and increased chamber pressure was beneficial to the melting of particle. It was revealed that as-sprayed coatings were mainly composed of metastable tetragonal phase except for minor content of cubic phase analyzed by XRD. Compared to air plasma spray (APS) coating, the microhardness and toughness of well-flatten LPPS coating are respectively high and excellent.
СКАРБ ДРІБНИХ МОНЕТ ПАНТІКАПЕЮ ТА ГЕРМОНАССИ КІНЦЯ VI – ПОЧАТКУ V СТ. ДО РХ З ПІВНІЧНО-СХІДНОЇ КІРОВОГРАДЩИНИ
Authors: Орлик Василь 
Published: September 2022

АНОТАЦІЯ
Контакти населення скіфської доби, як осілого, так і кочового, із греками Північного Причорномор’я залишили корпус різноманітних знахідок, у тому числі й античних монет. Серед корпусу знахідок давньогрецьких монет на території Північно-Східної Кіровоградщини – межі Лісостепу та Степу, особливе місце належить раннім монетам давньогрецьких полісів Керченської протоки.
Комплекс дрібних монет Пантікапею та Гермонаси кінця VІ – початку V ст. до РХ, як і цілий корпус інших знахідок давньогрецьких монет, свідчать про економічні, зокрема торгові зв’язки населення Степової та Лісостепової зони скіфської доби з античним світом. Знахідка скарбу дрібних срібних монет Пантікапею та Гермонаси на межі Лісостепової зони поряд із іншими відомими одиничними знахідками монет Боспору в цьому регіоні вказують на використання цих дрібних срібних монет у торгівельних операціях представниками грецьких апойкій Північного Причорномор’я із населенням навколишніх територій у період скіфської доби.
ТЕОРЕТИЧНІ ПІДХОДИ ДО ВИВЧЕННЯ МІГРАЦІЙНИХ ПРОЦЕСІВ В СРСР У ДРУГІЙ ПОЛОВИНІ ХХ СТОЛІТТЯ
Authors: Шихов Петро 
Published: September 2022

У статті зроблено спробу узагальнити теоретичні основи досліджень міграційних процесів у розвідках радянських дослідників другої половини ХХ ст.
Визначено, що поняття «міграція населення» має багато визначень. З’ясовано, що причиною різноманітності трактувань даного терміну є наукова спеціалізація конкретного дослідника, адже дослідженням міграції населення займалися фахівці з різних наук. Встановлено, що напрацювання за даного напрямку проводили дослідники з таких наук, як географія, економіка, соціологія, демографія.
З’ясовано, що розвідки зазначеного періоду умовно поділяються на три періоди. Перший період – це період відновлення, коли після сталінських часів було знято заборону на дослідження, і характеризується початком формування теоретичної бази за допомогою набутого досвіду у 1920-1930-х рр. Другий період (1960-1970-ті рр.) стосується емпіричних методів шляхом спостережень, щоб на основі отриманих даних покращити теоретичну основу майбутніх досліджень. Третій період (1970-1990-ті рр.) – час формування окремої науки «міграціології» та узагальнення в ній усього набутого практичного досвіду.
Виокремлено, що період відновлення досліджень з області міграції припадає на кінець 1950-х рр. Початок поновлення вивчення міграційних процесів відбувається у Сибірському відділенні АН СРСР. Визначено чому саме Сибір став базою для практичних розвідок в області міграції.
Зазначено низку науковців, які займалися формуванням теоретичної, а згодом і практичної бази досліджень. Описано сферу їх інтересів у цій царині. Визначено вклад, який зробили науковці задля формування єдиного теоретичного апарату, що потім трансформувався у окрему науку. З’ясовано, що вчені у своїх розвідках спираються лише на радянський досвід і формування теоретичної основи досліджень відбувається в ізоляції від міжнародного досвіду з даної галузі. Зауважено і про математичні спроби опису міграційних процесів на основі статистичних даних. Визначено мету досліджень з даної проблеми, адже вивчення міграції дозволяло ефективніше розробляти державну політику міграції населення, а також покращити промислову та містобудівну політику.
ДОКУМЕНТАЛЬНІ АРХІВНІ ІНФОРМАЦІЙНІ СИСТЕМИ З ПРОБЛЕМ МАТЕРІАЛЬНОГО ЗАБЕЗПЕЧЕННЯ НАСЕЛЕННЯ КИЇВЩИНИ В ХІХ – НА ПОЧАТКУ ХХ СТ. В СУЧАСНОМУ ІНТЕРНЕТ-ПРОСТОРІ УКРАЇНИ
Authors: Павленко Вікторія 
Published: September 2022

Процес введення документів НАФ України до наукового обігу (доступу), як відомо, має дві складові: фізичний доступ до первинних документів та доступ до інформації про первинний документ та його зміст. Останнє передбачає отримання необхідної довідкової інформації через документи вторинного рівня. Документальні архівні інформаційні системи мають забезпечувати інтелектуальний доступ до інформації, тобто реалізовувати другу складову доступу до первинної інформації.
У сучасних умовах розвитку цифрових технологій цифровізація всіх процесів архівної справи та діловодства є першочерговим пріоритетом роботи Державної архівної служби України. Сучасні дослідження проблем документальних архівних інформаційних систем тісно пов’язані з розвитком вивчення «інформаційного суспільства», зокрема «мережевого».
Проведений нами аналіз інформативності передачі вторинної інформації НАФ України з проблем історії повсякденності мешканців Київщини в ХІХ – на початку ХХ ст. електронними засобами та її доступності на офіційних сайтах трьох державних архівних установах: Центрального державного історичного архіву України в м. Києві, Державного архіву Київської області та Державного архіву міста Києва засвідчив, що сайти указаних архівних установ дають дослідникам доступну і досить повну вторинну інформацію з досліджуваної нами проблеми. У той же час, нині первинні документи НАФ України, на жаль, ще не представлені електронними засобами і з ними необхідно працювати безпосередньо в самій архівній установі.
Investigation and prediction of the extensional viscosity of okra mucilage using the Giesekus model
Authors: Minh Nguyen Ngoc 
Published: September 2022

BACKGROUND: Okra is a vegetable that is widely grown around the world. Okra mucilage contains a high mucus concentration that can be useful for supporting the swallowing process. Although the extensional rheology of okra mucilage is essential to its flow, its extensional viscosity has not received much attention. OBJECTIVE: Using a filament stretching rheometer, the extensional viscosity of the mucilage in okra was examined. The Giesekus model was used to predict this parameter. METHODS: The okra mucilage with different concentrations was extracted from fresh okra. The extensional viscosity was measured using a filament breakup apparatus. The diameter of the liquid bridge was measured by a laser micrometer and it was also observed by a high-speed camera. A rotational rheometer was used to measure the shear viscosity. In addition, the master curves for the shear viscosity were plotted to eliminate the influence of solvent and shear rate and evaluate the influence of concentration on the elasticity of okra mucilage. The okra mucilage shear and extensional viscosity were predicted using the Giesekus model. RESULTS: Every sample of okra mucilage exhibited shear thinning behavior. In addition to having a high extensional viscosity that is hundreds of times higher than its shear viscosity, okra mucilage also exhibited stretching phenomena. The master curves demonstrated that the pseudoplasticity of the okra mucilage increased along with the concentration. The rheological behavior of the mucilage in okra can be explained by the Giesekus model. CONCLUSIONS: Okra mucilage’s shear viscosity exhibited shear thinning behavior and a strong extensional viscosity that was significantly higher than its shear viscosity. The shear and extensional viscosity of okra mucilage can be described and predicted using the Giesekus model.