bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparative Study of the Melting and Atomization Properties of Iron-Based High-Carbide Alloys
Authors: Wielage B. , Schuberth S. 
Published: November 2022

Abstract
Thermally sprayed cermet powder coatings as well as bulk cermet materials sintered of carbide/metal powder blends are widely used in applications with severe abrasive wear conditions. A cost-saving alternative can be provided by using iron-based melt-atomised hard alloy powder feedstocks. Among them, commercial alloys containing high amounts of vanadium and carbon obtain outstanding wear resistance due to their high volume fraction of finely dispersed, hard vanadium carbides. However, their performance is still exceeded by cemented carbides. A further improvement of the wear properties of hard alloys basically can be attained by increasing their carbide content, concurrently considering the limitations of the melting and atomisation process regarding the melting temperature. A possible solution can be provided by alloying the basic system Fe-V-C with an additional strong carbide former like niobium. Subject of this work is the comparing investigation of the technologically important melting equilibria in the systems Fe-V-C and Fe-V-C-Nb.
Effect of Vacuum Heat Treatment on Tensile Strength and Fracture Performance of Cold-Sprayed Cu-4Cr-2Nb Coatings
Authors: Yu M. , Li W.-Y. , Zhang C. , Liao H. L. 
Published: November 2022

Abstract
A previous study indicated that dense thick Cu-4Cr-2Nb coatings could be formed by cold spraying, and the post-spray heat treatment could significantly influence the microstructure and microhardness of the as-sprayed Cu- 4Cr-2Nb coatings. In this study, the tensile strength and fracture performance of the Cu-4Cr-2Nb coatings after annealing were investigated. The vacuum heat treatment was conducted under 10-2 Pa at 850°C for 4 h. Results showed that the heat treatment had a great contribution to the healing-up of the incompleteness of the interfaces between the deposited particles. In addition, the coating microhardness decreased from 156.8±4.6 Hv0.2 for the as-sprayed coatings to 101.7±4.5 Hv0.2 for the annealed ones. The mean tensile strength of the annealed coatings was approximately 298.8±31.5 MPa compared to that of 45±10.5 MPa for the as-sprayed ones, which results from the partially metallurgically bonded zones between the deposited particles inducing by the heat treatment process.
Characterization of Mechanical Properties by Nanoindentation of Bimodal WC-VC-Co Coatings Processed by HVOF Thermal Spraying
Authors: Poblano-Salas C. A. , Cabral-Miramontes J. A. , Espinoza-Beltrán F. , Botello-De Jesús R. 
Published: November 2022

Abstract
The present investigation shows the fabrication procedure of bimodal WC-VC-Co coatings processed by the HVOF thermal spray process. The effects of nanostructured phase contents on the microstructure and wear resistance of the coatings are included. Special attention is drawn to the mapping of elastic properties within the cobalt matrix, which were measured by nanoindentation. Finally, the influence of VC additions on the size, morphology and stability of the WC phase is also discussed.
Mechanical Property of Multi-Pass Cold Sprayed Aluminium Alloy Coatings for Repair Application
Authors: Rech S. , Trentin A. , Vezzù S. , Legoux J.-G. , Irissou E. 
Published: November 2022

Abstract
The cold spray, for its peculiarity, is becoming increasingly in the reconstruction or repair of damage aluminium alloy components, especially in the aviation industry. Both thin (&lt;0.5mm) and thick (up to centimeters) coatings are necessary in order to achieve dimensional recovery of the components. Contrary to thin, thick coatings can be deposited in single-pass or in multi-pass giving different thermal and stress contribution to the components and coatings itself. The thermal input, the amount and the type of residual stresses (compressive or tensile) confer appreciable or depreciable characteristics to the coatings adhesion, the crack propagation and the coating mechanical property. In this study two sets, single and multi-pass aluminium alloy coatings of different thickness are deposited into Al6061 substrate. The metallographic analysis by electronic and optical microscopes, the four-point bending test and the Vickers microhardness are performed; also the multi-pass coatings were characterized by fractographic analysis. Finally the different coating adhesions to substrate and cohesions are compared by standard ASTM C633 adhesion and cohesion tests.
Milling and Cryo-Milling Affecting MCrAlY High Temperature Oxidation Mechanism
Authors: Giolli C. , Giorgetti A. , Scrivani A. , Bonferroni B. , Bolelli G. , Bozza F. , Lusvarghi L. , Fossati A. , DiFerdinando M. , Kim G. E. 
Published: November 2022

Abstract
This research aims to investigate the effects of employing cryo-milled and milled MCrAlY feedstock powders on the oxidation behaviour of low-pressure plasma sprayed (LPPS) and HVOF-sprayed coatings deposited onto a Ni-based superalloy substrate. Commercially-available powders with three different chemical compositions were selected and sprayed both in standard condition and after milling and cryo-milling processes. The LPPS and HVOF coatings, deposited onto an Inconel substrate, were diffusion-treated at 1080 °C (according to the industrial standard) and subjected to isothermal and cyclic oxidation tests. The outcomes of these tests show that transient oxidation is suppressed in the coatings obtained from milled MCrAlY systems, whose overall resistance to cyclic oxidation (number of cycles to failure) is approximately two times greater than that of standard coatings. This difference is not related to the nanostructural features induced on the powder particles by the milling process, because, after the diffusion treatment, all coatings exhibit identical γ-β two-phase microstructure, with no trace of the original nanostructure. The improvement is ascribed to the fine dispersion of nanometric Al2O3 grains within the milled powder particles: in the sprayed coatings, these nanometric oxides act as nuclei and favour the direct formation of an Al2O3 oxide scale.
Effect of Nitrogen Flow Rate on Mechanical Properties of Metallic Coatings by Warm Spray Deposition
Authors: Watanabe M. , Brauns C. , Komatsu M. , Kuroda S. , Katanoda H. , Gärtner F. , Klassen T. 
Published: November 2022

Abstract
In Warm Spraying (WS), the temperature of the combustion flame is reduced and controlled by injecting nitrogen gas into the combustion flame before the injection of spray powders. Thus, temperatures of spray particles are kept under their melting points with moderately heated and thermally softened states. As compared to HVOF-spraying, the oxidation of particles can be significantly suppressed due to lower deposition temperatures, whereas, as compared to cold spraying, the degree of particle deformation upon impact can be enhanced by attaining higher particle temperatures. In the present study, Ti, Cu, and Al coatings were fabricated by WS under various nitrogen flow rates. The mechanical properties of the coatings were evaluated by tubular coating tensile (TCT) and micro flat tensile (MFT) tests. For the lower impact temperature regime, the coatings became denser and the ultimate strengths of Ti or Cu coatings increased reaching a maximum by decreasing the nitrogen flow rates. A further decrease of nitrogen flow rates and reaching the upper temperature regime reduced the coating strength. These results clearly demonstrate how particle temperatures affect the microstructures and mechanical properties of WS coatings and that optimum spray conditions have to be balanced between softening and oxidation by adjusting particle temperatures.
Portable High Pressure Cold Sprayed Aluminum Alloy Coatings
Authors: Karthikeyan J. , Kay C. M. , Rininger M. W. , Brown E. C. , Steele M. S. , Porter J. , Eden T. J. 
Published: November 2022

Abstract
Superior characteristics of the cold sprayed coating have led to many high-tech applications. Until recently, all these applications were carried out using ‘stationary’ systems only, while some applications such as in-situ repair of aircraft body/engine parts require a portable system. Recently a ‘Portable High Pressure Cold Spray System’ called KINETIKS 2000-2 has been developed. This system is capable of 400 C/20 bars nitrogen/helium jet, and produces dense coatings with clean interfaces of many materials. In order to establish the suitability of this process for producing aluminum alloy coatings for aerospace and other high tech industries, various aluminum alloys (CP-Al, HP-Al, 6061 Al, 7005 Al) coatings were produced over many substrate materials (2024 Al, 7005 Al, 4041 Steel, ZE41A Mg). Coatings were characterized using microstructure, bond strength, bend test, corrosion studies, etc. Microstructural study showed that dense coatings with about 2-4% porosity values were produced with clean and well bonded interfaces. Bond strength of these coatings varied between 20 to 35 MPa, Bend test results showed that the coatings have adequate strengths and could withstand severe strain conditions. Salt fog corrosion studies (ASTM B 117) showed that the coatings impart corrosion resistance to the substrates.
Structural and Mechanical Properties Analysis of Si/Mullite/BSAS Environmental Barrier Coatings Exposed to Thermal Cycling in Water Vapour Environment
Authors: Cojocaru C. V. , Levesque D. , Moreau C. , Lima R. S. 
Published: November 2022

Abstract
The ongoing development of environmental barrier coatings (EBCs) offers the prospect to implement the full potential of silicon-based ceramics for high temperature structural applications. The current state-of-the-art EBC system comprises a Si bond coat, a mullite (3Al2O3·2SiO2) interlayer and a (1-x)BaO·xSrO·Al2O3·2SiO2, 0 ≤ x ≤ 1 (BSAS) crack-resistant and water vapour attack resistant top coat. In this study, the influence of water vapour corrosion on the structural and mechanical properties of plasma-sprayed Si/Mullite/BSAS architectures was assessed by furnace thermal cycle testing (e.g., 100 cycles, 2h/cycle at 1300°C). Commercially available mullite and BSAS powders were used to produce crystalline coatings by air plasma spraying. Fully crystalline mullite and celsian BSAS coatings were engineered under controlled conditions on silicon coated, sintered α-SiC Hexoloy substrates. The overall performance at high-temperature of these functionally graded EBCs is discussed and correlated to their microstructural characteristics.
Nano Modified NiCrAlY Coatings for Bond Coat for Gas Turbine Blades
Authors: Sahu S. , Khanna A. S. 
Published: November 2022

Abstract
Oxidation behavior of NiCrAlY powder, blended with nano and micro sized Al2O3 and Y2O3 was studied to understand the effect of nano/micro oxide powder dispersion. The blended powders were applied on the IN 718 substrates by HVOF technique. The present work compares the oxidation behavior of IN 718 superalloy, coated with NiCrAlY powders, dispersed with nano and micro Y2O3, Al2O3 oxide. Coated samples were characterized by XRD, SEM/EDAX in terms of surface composition, scale cross section and the identification of different phases. The oxidation tests were carried out at 1223K, 1323K, 1423K in air. Oxidation kinetics infer that at 1223 K and 1323 K, nano yittria addition, in fact, resulted in higher oxidation rate, while nano alumina addition resulted in lower oxidation rate. The effect was more pronounced at 1423 K, where the nano and micro size alumina, yttria addition, resulted in bringing down the oxidation rate considerably.
Deposition Behavior and Adhesion Strength of Cold-Sprayed TiO2 Particles
Authors: Yamada M. , Dickinson M. E. , Shima K. , Tjitra Salim N. , Nakano H. , Fukumoto M. 
Published: November 2022

Abstract
Cold-spraying has been developed as a high-quality metallic coating process. Recently, it became possible to fabricate a brittle ceramic coating using a particular nano-structured powder. In order to improve and control the process, the bonding mechanism should be understood. In this study, the bonding mechanism between cold-sprayed TiO2 particle and stainless steel substrate was investigated by cross-section observation and quantitative adhesion strength measurement for the individual particles. The adhesion strength was measured by the combination using of scanning probe microscope (SPM) imaging and nano scratch test. The result clearly revealed a correlation in adhesion strength with splat diameter. The smaller splat diameter exhibited higher adhesion strength, though it is generally difficult to penetrate the cold-sprayed small particles through a shock wave formed in front of the substrate. The cross-section microstructure of the splats prepared by focused ion beam (FIB) showed the particular deposition behavior of the TiO2 particle. The collided particle didn’t deform the substrate surface and deformed the particle itself. The bottom center of the splat is densified by the deformation and the other parts maintain the porous structure or broke up. Hence the higher adhesion strength of smaller splat was caused by this typical TiO2 deposition behavior.
Abnormal Intermetallic Compound Formation of Cold Sprayed Cu-Sn Coatings
Authors: Ko K. H. , Choi J. O. , Lee H. 
Published: November 2022

Abstract
Cu-Sn composites coatings by cold spray with wide ranges of particle size and shape (round to flake) were investigated regarding their intermetallic compound (IMC) formation. It was found when certain size and shape combination of Cu-Sn composite raw materials were employed, the embedded Cu-Sn IMCs such as Cu6Sn5 and Cu3Sn were observed even in as-sprayed states without additional heat treatments. These results implied that the impact energy of colliding particles of the cold spraying could be enough to activate IMC compounding process. It seems that this can be also true in several composite systems that have relatively low activation energy of IMC compounding. After post annealing, the Cu6Sn5 formed in as-coated state were transformed into the Cu3Sn phase and the residue of unreacted Sn particles were fully changed into the Cu3Sn phase (Cu6Sn5 →Cu3Sn). These conversion processes also depended strongly on the choices of the shape and size combinations of Cu and Sn particles.
B4C-Ni Composite Coatings Prepared by Cold Spray of Blended or CVD-Coated Powders
Authors: Feng C. , Guipont V. , Jeandin M. , Amsellem O. , Pauchet F. , Saenger R. , Bucher S. , Iacob C. 
Published: November 2022

Abstract
In the oil industry, logging systems involving geological sensors are designed to operate under increasing severe service conditions of deep and horizontal boreholes. Under these conditions, metal matrix composites (MMCs) with ceramic reinforcement are applied on components to achieve wear and corrosion resistant systems. The ‘cold spray’ could be described as a cold and inert process to form coating layers through severe plastic deformation of a ductile metal. Ceramic/metal MMC coating could be achieved by co-deposition of a ceramic with a ductile material. In this work, it was it was investigated the use of MMC B4C-Ni coating from both mechanically milled blends or B4CNi CVD coated batches. Powder blends involving Ni powder with fine or coarse B4C powders were prepared by mechanical milling. Three CVD coated B4C-Ni powder batches were synthesized with 30, 40 and 50 Ni wt% respectively. Cold spray coatings were achieved with 1 pass and 5 passes to investigate the building-up mechanisms and interfaces with AISI316L. Powders and cold sprayed coatings microstructures were observed by optical and scanning electron microscopies and further quantitative image analysis were carried out to determine the content of B4C embedded in the Ni matrix of B4C-Ni cold spray coatings. The highest B4C vol.%, up to 45%, could be reached in the case of B4C-Ni coated powder. Micro-hardness values of such MMC coatings were also determined through Vickers micro-indentation. The beneficial role of the Ni surrounding layer on coating formation is discussed in relation to the unique features of the microstructures obtained by cold spray of B4C-Ni coated powders.
What are the Benefits of an Association Such as GTS for a Thermal Spray Company?
Authors: Krömmer W. , Heinrich P. 
Published: November 2022

Abstract
GTS is now almost 20 years old and has nearly 200 members from all thermal spray sectors. In this time, a great deal has been accomplished and GTS members are already using those tools GTS has made available to them and which are important for them. Here, the original idea of enhancing the quality of our technology and maintaining it at a high level continues to be an essential building block. In addition, many areas have been accessed in which an association can make more effective progress than each company on its own. With respect to issues such as further education and training, safety, environment, REACH and the compilation of guidelines, to name but a few, this idea has been successfully applied. The work of many in our organization has yielded many fruits and continues to make a difference. However, the benefits for each of us only become visible if we all actively work together. What is central to all the advantages which GTS offers is the candid discussion among its members and the opportunity for each member to quickly find his place in the group and to put these benefits to good use. The fundamental idea which GTS represents has therefore not changed in all this time: a high quality standard, cooperation, education and training, public relations all combined within the association’s guidelines and many working papers which are available to its members.
Ultra-Small Angle X-Ray Scattering (USAXS) in-situ Quantification of Void Network Evolution During Annealing of Nanometer-Sized YSZ Plasma-Sprayed Coatings
Authors: Montavon G. , Ilavsky J. , Denoirjean A. , Fauchais P. , Bacciochini A. , Wittmann-Teneze K. 
Published: November 2022

Abstract
Suspension plasma spraying (SPS) is able to process a stabilized suspension of nanometer-sized feedstock particles to form thin (from 20 to 100 µm) coatings with unique microstructures. The void network architecture of these ceramic coatings is a challenge to be characterized and quantified using commonly used techniques due to small sizes involved. Nevertheless, the discrimination of these pore architectures in terms of size and shape distribution, anisotropy, specific surface area, etc., is critical for the understanding of processing, microstructure, and properties relationships. USAXS (Ultra-Small Angle X-Rays Scattering) appeared as a suitable measurement technique allowing discriminating the void size distribution over a large range (up to four orders of magnitude). Results indicate that as-sprayed SPS coatings exhibit unusual porous architecture: 1) average void size is about the same than the feedstock one; i.e., nanometer sizes with multimodal void size distribution; 2) about 80% of the voids exhibit characteristic dimensions smaller than 30 nm; 3) the total void content varies between 13 to 20% depending upon considered operating parameters. In-situ annealing measurements were performed as they proved to deliver more relevant results compared to ex-situ measurements: even at temperatures as low as 800°C, the microstructure transforms - while the total void content does not change significantly. Indeed, it has been demonstrated that the smallest voids (equivalent diameters smaller than 50 nm) coalescence was the predominant mechanism and that it was more sensitive to temperature than time.
Localized Zinc Coatings on Automotive Steel Sheets by Cold Spray Technology
Authors: Ducos M. , Gay B. , Verbiest P. , Verschave Ch. , Hoel H. , Vanden Eynde X. 
Published: November 2022

Abstract
Zn coatings have been applied on steel substrates used by Renault for the manufacturing of car bodies. We had the task to make these on-line thin coatings on smooth and non de-oiled surfaces with a translation speed of 1 m/s. Furthermore, in certain cases, these coatings were situated on a visible surface of the car body and on a precise position. The coating process must be adapted to the clean conditions of the current automotive industry. The development of this application has been focused mainly on the study of a new zinc powder grade as well as on the projection procedure which had to adapt to the constraints and to the productivity of an automotive manufacturing line. Cold Spray addresses all these requirements. Positive results obtained on the mechanical examinations, the accelerated corrosion tests and chippings tests demonstrate that such new coatings meet the specifications of the customer for this kind of processes.
Sliding Wear Behavior of HVOF Sprayed Metal Matrix Carbides
Authors: Altuncu E. , Ustel F. , Turk A. , Uzun A. 
Published: November 2022

Abstract
WC-CoCr coatings are deposited by HVOF process for improving surface resistance of low alloyed steels. In this study we examined the wear characteristics of WC-CoCr coatings on low alloyed steel substrate under different test conditions, using a sliding wear test unit with abrasive ball. In experimental studies discussed the effects of test load, temperature, work medium and sliding distance on the wear characteristics of coatings. Weight loss, wear track depth and width were observed . It was found that the weight loss of coatings increased in dry medium conditions. Wear weight loss was significantly reduced in lubricated condition due to decreasing friction. The wear track surface profile changed with lubrication and increasing temperature in test conditions. Under the base oil lubricated conditions the WC-CoCr coating performed well.
Analysis of Ni-Al Coatings In-situ Processed by Plasma Transferred Arc
Authors: Brunetti C. , Mendes F. H. , Pintaude G. , D’Oliveira A. S. C. M. 
Published: November 2022

Abstract
Ni-Al intermetallic alloys are known for exhibiting superior high temperature properties. Processes such as thermal spray, combustion synthesis, physical vapor deposition and laser have been used to produce these coatings. However, the deposition of these alloys by means of plasma transferred arc (PTA) has not been widely studied. This study evaluated Ni-Al coatings processed in-situ by PTA. Coatings were processed with Ni and Al elemental powders (65%atNi-35%atAl) onto an AISI 1020 steel substrate. Different current intensities were used (70 to 120 A) to produce different dilution levels and thus different Fe contents in the coatings. The stand torch off was 10.0 mm. The plasma gas, shield gas and powder carrier gas flows were 2.0, 15.0 and 1.0 l.min-1, respectively. The powder feed rate was 5.8 g.min-1 and a travel speed of 100 mm. min-1 was used. The coatings were characterized by X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, optical microscopy and instrument indentation tests. The development of Ni aluminides was confirmed by X-ray diffraction for all current intensities. It was verified that the microstructure, hardness and the elastic modulus were influenced by current intensity and by the Fe content in the coatings.