bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ambient and High Temperature Thermal Conductivity of Thermal Sprayed Coatings
Authors: Chi W. , Sampath S. , Wang H. 
Published: September 2022

Abstract
Aside from its importance as a design parameter for thermal barrier coatings, measuring thermal conductivity of thermal sprayed coatings itself provides a unique method to critically characterize the nature, quantity and anisotropy of the defect morphologies in these splat-based coatings. In this paper, we present a systematic assessment of thermal conductivity of wide range of thermal sprayed coatings using the flash diffusivity technique. For the case of plasma sprayed yttria-stabilized zirconia (YSZ), coatings obtained from wide ranging initial powder morphologies as well as those fabricated under different particle states were characterized. Both in-plane and through-thickness properties were obtained. Other material systems that were considered include: metallic alloys, semiconductors and other oxides of interests. Issues such as reproducibility and reliability in measurements were also considered and assessed. Finally, working in collaboration with the Oak Ridge National Laboratory (ORNL) for alternate approaches to characterization of thermal conductivity as well as high temperature measurements was performed.
PTA Hardfacing Material for Earthmoving Equipment Applications
Authors: Jiang X. , Beardsley M.B. 
Published: September 2022

Abstract
Plasma transferred arc welding (PTA) is used to produce coating for wear resistance application in earth moving equipment. The coating is designed to have balanced toughness and hardness, optimal microstructure to perform in the wear modes the components are subject to. 4~ 6 times improvement in wear life compared with hardened steel was achieved as demonstrated in dry sand/rubber wheel test and Caterpillar proprietary abrasion wear test
Laser and PTA Surfacing with TiC-based Materials
Authors: Techel A. , Berger L.-M. , Bretschneider J. , Thiele S. 
Published: September 2022

Abstract
The specific advantages of TiC as a hard material are its low density, high hardness and the high alloyability of the hard phase - binder metal composite. Currently developed agglomerated and sintered core-rim structured TiC-based powders were intensively studied in the last few years for thermal spray coating solutions. In the work described in this paper two different powders with cubic (Ti,Mo)C and (Ti,Mo)(C,N) hard phases and Ni/Co binder, representing the first and second alloying step for the binary TiC-Ni/Co composite, were used together with mechanically mixed NiBSi powder to produce wear resistant coatings by plasma-transferred arc welding (PTA) and laser cladding. Basic process parameters, coating microstructures and properties are described. Coatings with fine grained hard particles were obtained by both processes, while the coating prepared from the nitrogen-containing powder by laser cladding shows a significant smaller hard particle grain size and increased hardness.
Deposition of Thick Wear and Corrosion Resistant Coatings by High Power Diode Laser
Authors: Tuominen J. , Latokartano J. , Vihinen J. , Vuoristo P. , Mäntylä T. , Naumann T. , Scharek S. , Berger L-M. , Nowotny S. 
Published: September 2022

Abstract
High power diode lasers (HPDL) at the level of ? 6 kW are efficient cladding tools in heavy engineering applications where thick (up to 5 mm) wear and corrosion resistant coating layers are required. Large beam geometry makes possible the overlap of thick 20 mm wide cladding tracks side by side without coating defects. Compact size and closed cooling water circulation enable HPDL cladding process to take place also at a site of new or worn high-value machine parts, which have worn in operation or been damaged already during overseas transportation. Instead of moving parts of several tons’ weight, it would be perhaps more cost efficient to transport HPDL cladding unit.
Optimisation of Laser Cladding Process Using Taguchi and EM Methods for MMC Coating Production
Authors: Dubourg L. , St-Georges L. 
Published: September 2022

Abstract
This study investigates the influence of laser cladding parameters on the geometry and composition of metal-matrix composite (MMC) coatings. Composite coatings are made of a Ni-Cr-B-Si metallic matrix and of WC reinforcement with a volume fraction of 50 %. Optical microscopy is used to characterize the coating geometry (height, width and penetration depth) and to determine the real volumetric content of WC. Laser cladding on low carbon steel substrate is carried out using a cw Nd:YAG laser, a coaxial powder injection system and a combination of Taguchi and EM methods to design the experiments. This combination explores efficiently the multidimensional volume of laser cladding parameters. The results, which express the interrelationship between laser cladding parameters and the characteristics of the clad produced, can be used to find optimum laser parameters, to predict the responses and to improve the understanding of laser cladding process.
Scientific, Technological and Economic Aspects of Rapid Tooling by Electric Arc Spray Forming
Authors: Grant P.S. , Duncan S.R. , Roche A. , Johnson C.F. 
Published: September 2022

Abstract
For the last seven years, Oxford University and the Ford Motor Co. have been researching jointly the development of the large-scale spray forming of steel tooling capable for use in mass production, particularly for the pressing of sheet metal in automotive applications. These investigations have involved: comprehensive microstructure and property studies, modelling of shape evolution and heat flow, real-time feedback control of tool temperature to eliminate tool distortion, high speed imaging and particle image velocimetry of droplet deposition on 3D shapes, the testing of full-scale tools for different applications in the production environment, and detailed studies of the cost and time savings realised for different tooling applications. This paper will provide an overview of the scientific and technical progress to date, present latest results, and describe the current state-of-the-art. Many of the insights described have relevance and applicability across the family of thermal spray processes and applications.
Nozzle Modification for Property Improvement of Arc Spray-formed Steel Tools
Authors: Kim J.-H. , Seong B.-G. , Ahn J.-H. , Baik K.-H. 
Published: September 2022

Abstract
Modification of the nozzle of the arc spray equipment was attempted in order to reduce microstructural defects of the spray-formed steel shells since these defects mainly degrade the overall properties of the spray-formed tools. Based on the in-flight particle analysis, a new nozzle design of a gas shrouding concept was proposed. Effects of design factors such as nozzle dimensions and process conditions was investigated by using statistical analysis methods. The results demonstrated that the oxidation of the spray-formed steel shells can be reduced to the one-third levels of the original ones with an optimized design.
Functionally Graded Net-shape Component Fabrication by Hybrid Spray Process
Authors: Kosikowski D. , Ostrom T. , Mohanty P.S. 
Published: September 2022

Abstract
Functionally graded material (FGM) designs aim to combat challenges posed by harsh and conflicting operational requirements. There is a great demand for manufacturing technologies that can fabricate net-shape components incorporating the FGM design concepts. The focus of this paper is on the development of net-shape components incorporating functionally gradient material designs. This novel manufacturing scheme combines the use of re-useable mandrels to generate complex shapes with a unique thermal spray process called “hybrid spray” that can deposit functionally designed materials. This generic hybrid spray process combines arc spraying with either high velocity oxy-fuel (HVOF) or plasma spraying (APS). The resulting benefits are; ability to achieve continuous composition variation, high deposition rates combined with the high coating densities. The multi-material component designs aim to provide cost as well as performance advantages. The geometric resolution and dimensional accuracy of these functional components are presented. This paper also reports results on material compatibility and process parameter development tests. Functional properties such as high temperature resistance and thermal fatigue performance are also reported.
Aspects of Thermal Spray Molding of Micro Components
Authors: Wilden J. , Bergmann J.P. , Luhn T. 
Published: September 2022

Abstract
In this paper the principle of “Thermal Spray Molding” and some application are presented. Micro technology is a very fast growing market nowadays. Metallic micro devices can be produced for example by means of stereo lithography and selective etching. Unfortunately the material range for these processes is limited. The new manufacturing concept of thermal spray molding uses powder or wire as base material, so that an extended material choice for micro parts, for example micro components made of super hard or corrosion resistant steel is possible.
Ni-Cr Coatings Deposited on a Magnesium Alloy Substrate Using the PROTAL Process
Authors: Li H. , Costil S. , Deng S-H. , Coddet C. , Liao H-L. , Richardt K. , Lugscheider E. , Bobzin K. 
Published: September 2022

Abstract
Being the 7th most abundant element on the earth, magnesium and its alloys have become very promising in numerous industrial applications because of some of their distinguished properties, including high thermal conductivity, high strength/weight ratio, good machinability etc. However, some inferior properties especially the poor wear and corrosion resistance have obstructed a widespread use. As one of the most effective solutions, thermal spraying can deposit an adequate protective coating on the substrate, but the necessary grit-blasting operation before spraying leads to high grit-residues on the magnesium surface therefore degrading the deposit performance. The PROTAL® process, combining a laser surface preparation with the deposition stage, can avoid this kind of disadvantage. This paper presents the possibility of employing PROTAL® to prepare a resistant Ni-Cr coating on a magnesium substrate. The coating adhesion and interface microstructure were especially investigated.
Heat Treatment Effects on the Tribological Performance of HVOF-Sprayed Co-Mo-Cr-Si Coatings
Authors: Bolelli G. , Lusvarghi L. 
Published: September 2022

Abstract
The tribological behaviour of HVOF-sprayed Co-28%Mo- 17%Cr-3%Si coatings, both as-sprayed and after heat treatments at 200°C, 400°C, 600°C for 1h, has been studied. Microstructural and micromechanical properties were characterized by SEM, XRD, depth-sensing indentation (microhardness, elastic modulus, indentation fracture toughness); pin-on-disk dry sliding wear tests were performed against 100Cr6 and sintered alumina spherical pins. The as-sprayed coating contains splat boundary oxide stringers and is mostly amorphous (splat quenching). It has low hardness (≈6.7GPa) and toughness (≈1MPa*m1/2); thus, much adhesive wear occurs against 100Cr6 steel. The friction coefficient increases up to ≈0.9, raising the contact point temperature up to a critical coating oxidation value; then, it decreases, increases again and finally settles. Much of the adhesive wear occurs in the first stage of the test. Abrasive wear prevails with the alumina pin: the coating wear rate is lower because the metallic alloy possesses intrinsically good plasticity. Adhesive phenomena still occur, leading to the same thermal effects. After the 200°C and 400°C heat treatments, no major changes occur. The 600°C treatment causes the formation of some submicrometric crystals. The hardness increases (≈8.8GPa), adhesion to steel pin is prevented, and the friction coefficient soon settles at ≈0.8 with no peaks. The coating undergoes no wear loss and the pin wear rate largely decreases. With the alumina pin, coating and pin wear rates remain quite low. However, adhesion is reduced, so that the friction coefficient has no peaks and its final value is lowered (from 0.84 to 0.75).
Effects of Blasting Parameters on Removability of Residual Grit
Authors: Maruyama T. , Akagi K. , Kobayashi T. 
Published: September 2022

Abstract
A carbon steel was blasted by white alumina, and removability of residual grit was investigated. Blasting parameters such as grit particle size were varied. Residual grit was removed from substrate surface by dissolving the substrate in mixed acid solution, and the amount of residual grit was measured. Removal of residual grit was carried out by ultrasonic cleaning. The amount of residual grit was 7-17 g/m2, and penetration depth of embedded grit of most residual grit was 25-40 µm. The amount of residual grit increased with decreasing the grit size. However, the minimum amount of the substrate dissolution required for the grit removal increased with increasing the grit size.
Influence of Substrate Surface Roughness on Adhesive Strength
Authors: Yang H. , Wang H.G. , Cao X.P. , Wang L. 
Published: September 2022

Abstract
The adhesive strength between substrate and sprayed coatings seems to be mainly due to the mechanical interlocking effect. The physical bonding of spray particles to the substrate is the second factor. In this paper, the bonding mechanisms of sprayed coatings were studied on basis of experiments with the substrate at different surface roughness. The substrate surface roughness was quantitatively evaluated using a surface roughness tester. The tensile adhesion strength test method was used to evaluate the adhesive properties. The relationship between surface roughness and adhesive strength was investigated. The adhesive strength of plasma sprayed coating decreased with an increase in substrate surface roughness, as the size of the grit particles for roughening increased. On the contrary, the adhesive strength of arc sprayed coating increased.
Choosing the Right Coating Technology for the Application
Authors: Legg K. 
Published: September 2022

Abstract
With the vast array of coating technologies and materials available in the marketplace, matching the best coating to an application is far from a trivial task. There is a tendency on the part of vendors, for example, to put forward any hard coating as a chrome replacement or any corrosion-resistant coating as an alternative to cadmium. At the same time users often attempt to shoehorn the coatings with which they are most familiar into applications for which they are not well-suited. This paper will discuss how best to match the application to the best technology and material, considering all the critical requirements of fit, form and function, with particular reference to alternatives for chrome and cadmium plating.
Hybrid Plasma Spray – PVD Coatings in Triple Torch Plasma Reactor
Authors: Heberlein J. , Kolman D. , Chen' H. 
Published: September 2022

Abstract
A reactor and process are described that allow the variation of the plasma deposition conditions such that a wide range of coating properties can be obtained. The reactor consists of three plasma torches mounted such that the deposition precursors can be injected centrally into the merging jets. This reactor has been used to deposit the different layers of a solid oxide fuel cell, including the very dense (99.5% density) zirconia electrolyte layer. Investigation of the zirconia layer showed a microstructure which has characteristics of both plasma sprayed coatings and vapor deposited coatings. The region of particle heating and acceleration has been characterized with enthalpy probes resulting in velocity and temperature fields. Calculations have been performed to describe the particle heating histories. The results show that a significant fraction of the particles evaporate and condense at the surface thus contributing to the formation of the dense layer. This hybrid process combines the possibility of obtaining high density coatings as with a PVD process with the rapid deposition rate of a plasma spray process.
Environmentally Safe Alternative Chrome Application Technology for the Automotive Industry
Authors: Sunthankar M. 
Published: September 2022

Abstract
Conventional decorative chrome plating operations are known to be environmentally and occupationally hazardous because of the use of hexavalent chromium and other toxic chemicals. An alternative ArcBright™ chrome technology has been developed to eliminate these hazards and simultaneously simplify manufacturing methods in this industry. The application method presented here uses an organic base coat and a physically vapor deposited (PVD) chrome to replace electroplated copper-nickel-chrome structure. An advanced rapid cycle, high rate PVD chrome coating method has been developed for this application to be able to increase throughput to the levels required in the automotive sector and to minimize application cost. The technology is applicable to many metals, plastics, composites and other solid materials that are not possible by conventional electroplating providing a wider choice of substrates. The PVD chrome process has been characterized and the ArcBright chrome has been qualified to automotive specifications.
Thermal Sprayed Coatings in High-Performance Agricultural Machinery: Properties and Wear-Behaviour Test Routine
Authors: Lugbauer M. , Kroll A. , Badisch E. , Polak R. , Franek F. 
Published: September 2022

Abstract
Cutting tools in agricultural machines have to withstand high wear demands. Longer maintenance cycle intervals of these tools can be achieved using coatings reinforced with hard particles, applied onto tool substrates. This work was done to establish the qualified test procedure to characterize carbide containing spray & fuse coatings for agricultural demands under abrasion and impact. Simulating these field conditions in lab-scale, tests were performed with a standard ASTM G65 dry-sand rubber-wheel tester (3-body abrasion) and a special impeller-tumbler apparatus (combined impact and abrasion wear). The interaction of hardphase content and matrix composition was investigated to assess their response varying impact energy effects. The test procedure described is suited to optimize coatings by combining quantitative mass loss measurement with results of surface profilometry. It is shown, that crucial material criteria of carbide coatings, such as edge stability and wear progress, can be characterized in a way which is able to tailor coatings for targeted wear regimes in agriculture.
Fretting Wear Behavior of Plasma Sprayed Cu-Ni-In Coating and Cu-Ni-In+MoS2 Composite Coatings
Authors: Paul S.N. , More N.S. , Murthy J.K.N. , Roy M. , Venkataraman B. 
Published: September 2022

Abstract
In many aeronautical applications such as in the fan blade / disk dovetail notch, two parts made up of a titanium alloy are in contact and relative motion between them can occur. Titanium alloys like Ti-6Al-4V are promising candidates for tribological application because of their low weight and high specific strength. However, because of the poor tribological behavior of Ti-6Al-4V under self-mating conditions, modification of the surface has become imperative. In this work, we report on the fretting wear of plasma sprayed Cu-Ni- In along with MoS2 solid bonded lubricant and Ti-6Al-4V. Substrate coated pins were tested against a flat plate of Ti- 6Al-4V alloy. The effect of temperature and frequency on fretting wear of Cu-Ni-In, the composite coating and Ti-6Al- 4V was investigated. Wear properties of the coatings and substrate were evaluated. The morphologies of the worn surfaces and surfaces beneath the worn surfaces were characterized with the help of an optical microscope, scanning electron microscope, electron probe micro analyzer and energy dispersive spectroscopy. Results showed that the composite coating exhibited better fretting resistance than the Cu-Ni-In plasma sprayed coating with no additive. It also exhibited lower surface roughness and a lower coefficient of friction than Cu-Ni-In or Ti-6Al-4V under the same testing condition. Therefore, the use of MoS2 solid bonded coating scan be considered as one of the possible simple and cheap approaches for reducing fretting wear.
Frictional Properties of M3B2 Boride Cermet Coating
Authors: Hamashima K. , Tomita N. 
Published: September 2022

Abstract
The boride cermets composed of M3B2 (M: metal)-system complex borides and metals, have attained superiority over carbide cermets in various mechanical properties. However, their sintered materials have been put into only limited use due to the cost. Therefore, thermal spray coating of the boride cermets was investigated. The powders for thermal spray were prepared by low temperature sintering, and the spraying was performed by HVOF. Microstructure of the sprayed layer was finer, and its hardness was superior to that of a body sintered in vacuum having the same composition. It is clarified that these boride cermet coated layers have outstanding sliding properties. Instantly frictional stress between this boride cermet layer and glass at high temperature is extremely low compared to other materials.
Development of Self-Lubricating Coatings for Ti-6Al-4V Dovetails using a High- Velocity-Particle-Consolidation (HVPC) Process
Authors: Aggarwal G. , Walia P. , Segall A.E. , Smid I. , Eden T. 
Published: September 2022

Abstract
Because of their low density, high specific strength, and high stiffness, titanium alloys are one of the prime candidates for structural application often requiring specific tribological properties. However, their relatively high friction coefficients and low wear resistance are limiting their application over a wider range of temperature. Various coating technologies are currently available to enhance the surface by improving wear and friction characteristics. While the most widely used methods (High-Velocity Oxy-Flame (HVOF), Detonation-Gun (D-Gun), Electron-Beam Physical Vapor Deposition (EB-PVD), etc.) can improve wear performance and decrease corrosion damage, the required higher temperatures usually preclude the integration of thermally vulnerable lubricants. In this research, a low temperature, High-Velocity-Particle Consolidation process (HVPC) was investigated for coating Ti-6Al-4V due to its various advantages over conventional thermal spray processes. The optimum feedstock (nickel + solid-lube) for self-lubricating coating has been developed and compared with respect to different particle sizes and particulate composites. The coating characteristics and its microstructural homogeneity were assessed at various operating parameters and feedstock compositions.
Thermal Spray Coatings from WC-Co Powders Produced by Mechanically Activated Synthesis
Authors: Zimakov S. , Peetsalu P. , Pirso J. , Kulu P. , Mikli V. 
Published: September 2022

Abstract
In the present study WC-Co feedstock powder was produced by the process termed mechanically activated synthesis (MAS). The main characteristics of the powder (particle/granules size, size distribution, morphology, chemical composition and granules microstructure) were determined. The material was sprayed by the HVOF process to investigate the properties of the coatings in comparison to standard materials. The microstructure, phase structure, porosity and microhardness values of the coatings were studied. The abrasion wear resistance of the coatings was evaluated by rubber wheel abrasion tests. Results of abrasive wear tests show that the new material has superior properties compared to conventional WC-Co coatings.