bluuebunny/crossref_metadata_2025_split huggingface dataset:
Plasma Spraying of Thick Stainless Steel Coating of a Stereolithography Resin
Authors: Hédacq S. , Borit F. , Guipont V. , Jeandin M. , Guyen F.N. , Gibert R. , Guilhot B. , Medard C. 
Published: July 2021

Abstract
The use of plasma spraying can be very beneficial in a rapid prototyping/manufacturing route for producing industrial metallic parts, e.g. tools and molds. Compared to the most recent and advanced laser-based or flame/arc spray-based methods, plasma spray basically shows a higher efficiency and process control in addition to a wider range of coating materials and better coating properties. This work deals with plasma spraying of AISI 316 stainless steel onto conventional MVA 200 acrylate resin as the second stage of a rapid prototyping route involving stereolithography plus plasma spray. This resulted in a 3 key issues : - Achieving a good coating/substrate adhesion, notwithstanding the preventing from previous grit blasting of the resin and poor physico-chemical bonding between the organic substrate and stainless steel ; - Good building-up of the sprayed particles up to a rather high thickness (i.e. of a few mm) through adequate plasma spray conditions, which limits the residual stress level; - Coating conforming closely to the substrate geometry, which precludes from surface damaging under spraying. The work showed that the process can meet all the previously-mentioned requirements combined with the achievement of high-quality coatings (i.e. with a low porosity in particular). A major part consisted in optimizing the plasma spray conditions using a CAPSATC ("Controlled Atmosphere/Temperature Plasma Spraying") unit. This included the development of an original thermal pre-treatment of the substrate (patented), namely "PINPRO", to promote coating/substrate adhesion. SEM, EDS, EPMA, FTIR, QIA (Quantitative Image Analysis), ... were particularly employed to study microstructures and interfaces. Phenomenological approaches to the involved adhesion mechanisms and coating build-up are discussed. For the latter, the first steps in the application of Lattice-Gas Modeling (LGM) of stainless steel layer build-up were made. LGM is a new and powerful simulation tool for the spray operator or user.
Preliminary Investigation on the Potential of VC-WC-Co HP/HVOF Powders and Coatings
Authors: de Villiers-Lovelock H.L. , Luyckx S. 
Published: July 2021

Abstract
It has been observed that VC-WC-Co hardmetals have a better wear resistance than conventional WC-Co hardmetals. This work represents a first attempt to add VC to thermal spray powders in order to determine whether this would increase the wear resistance of HVOF hardmetal coatings. Standard WC-Co and WC-CoCr thermal spray powders were compared to two experimental VC-WC-Co powders in terms of size distribution, morphology and phase composition. Coatings were produced from the powders using the TAFA JP-5000 High Pressure High Velocity Oxy-Fuel (HP/HVOF) process. The microstructure, phase composition, hardness, dry solid particle erosion and three body abrasion of the coatings were compared. It was found that due to the non-homogeneous dispersion of VC particles in the powders, the experimental coatings were not optimised. Nevertheless they showed some advantage over the conventional coatings, particularly in low angle erosion tests. This result is regarded as promising, and it is believed that a homogeneous dispersion of VC particles in the coatings would result in a significant increase in wear resistance. In order to test this, the manufacture of improved powders and optimised coating microstructures would be necessary as a next step.
Enhanced Copper Coating Properties Obtained by Electric Wire Arc Spraying Process
Authors: Gourlaouen V. , Verna E. , Beaubien P. 
Published: July 2021

Abstract
Among the different wires used in arc spraying, copper is a material of choice in some applications. Its malleability is used to allow an easy machining procedure after spraying. This article focuses on the limitations of the oxidation of copper during arc spraying and its influence on coating process and properties. The aim of this series of experiments was to improve coating properties of copper sprayed with the electrical wire arc spraying process by substituting compressed air with nitrogen. These experiments show that coating properties, as well as electric wire arc spraying process, are strongly influenced by the gas employed as the atomising element.
Investigations of Arc Behavior and Particle Formation in the Wire Arc Spray Process Using High Speed Photography
Authors: Hussary N.A. , Heberlein J. 
Published: July 2021

Abstract
The wire arc spraying process, one of several thermal spray processes, gained a sizable part of the thermal spray market, however, more control is needed for this process to be used for high precision coatings. This study is aimed at investigating the liquid metal droplet formation process in order to identify methods for droplet trajectory control. A high speed Kodak imaging system has been used to observe the droplet formation for different operating conditions. Decreasing the upstream pressure and the current levels lead to the reduction in the asymmetric melting of both anode and cathode. By decreasing the interactions of the large eddy structures with the formed metal agglomerates one can achieve better control of the particle trajectories and jet divergence. Thus, coatings can be obtained with higher definition and improved reliability.
Visualization of Particle Impact in Thermal Spray
Authors: Escure C. , Vardelle M. , Fauchais P. , Grimaud A. 
Published: July 2021

Abstract
Many studies have been devoted to particle flattening and resulting splat cooling. However, if recent models allow to compute the particle flattening time evolution, very few experiments in spraying conditions have been achieved to back such calculations. The aim of this paper is to describe an imaging device allowing the visualization of particle impacts on cold and hot surfaces. This technique makes it possible : • to investigate the "impact mode" : splashing, deposition or rebound, • to link the particle parameters at impact and the substrate parameters to the observed impact mode, • and therefore, to have a better understanding of coating formation. It consists in a controlled atmosphere chamber where is followed the impact of a single particle on a substrate which can be inclined. The particle parameters prior to its impact are measured : its surface temperature by fast (100 ns) two-color pyrometry, its velocity and diameter by Phase Doppler Anenometry (PDA). The particle image during flattening, splashing or rebounding is given by a fast camera (exposure/delay time 100ns to 1ms) with possible multi exposures. The camera is triggered by the PDA and/or the pyrometer. It is then possible to calculate for each molten particle its Sommerfeld parameter characterizing its impact mode (rebounding, deposition or splashing) when no solidification occurs during flattening. The substrate are made of stainless steel 304L rapidly covered by alumina splats resulting in a Ra~5-6µm. They are kept at 300°C, temperature at which splats are disk shaped on smooth substrate (Ra&lt;0.05µm). The very preliminary results obtained show that unmolten or partially molten particles rebound in all directions but not elastically : the rebounding particle velocity is 3 to 5 times lower than that of the impacting one. For fully molten particles, splashing occurs in all cases even for low Sommerfeld numbers. It thus seems that the substrate roughness plays a key role in splashing.
Splat Formation in Off-Normal Angle Spray
Authors: Fukanuma H. , Huang Y. 
Published: July 2021

Abstract
This article examines the splat shape at off-normal angles in plasma spray and investigates the relationship between the splat elongation ratio and the spray angle on various spray materials and particle sizes. The applicability of the model to the experimental results is investigated. In this study, six powders of aluminum, copper, and nickel as metal spray materials and of alumina, titania, and zirconia as oxide materials were sprayed. It was observed that the model agreed well with the elongation ratio of the experimental results in the range between 90 and 30 degree. The model values were over-estimated than the practical results at spray angles less than 15 degree.
Thermally Sprayed Quasicrystal Composite Coatings for Bearings and Other Friction Threaded Applications
Authors: Lugscheider E. , Herbst-Dederichs C. , Reimann A. 
Published: July 2021

Abstract
Quasicrystalline phases improve many alloy properties such as thermomechanical stability, thermal and electrical conductivity, and tribological performance. High hardness, however, is accompanied by brittleness, an undesired property in many applications. Reduced brittleness can be achieved by embedding quasicrystalline phases in a more ductile material, forming a metal-matrix composite that retains some quasicrystalline properties. This study evaluates thermally sprayed coatings made from different compositions of such composites. The coatings assessed were produced by arc-wire, HVOF, and atmospheric plasma spraying using various forms of feed material, including blended, agglomerated, chemical encased, and attrition-milled powders and filled wires. The investigation involved metallurgical analysis, proving the existence of quasicrystal content and assessing the matrix phase, and tests showing how sliding wear is influenced by the composition of quasicrystalline phases.
Plasma Arc Spraying of Cu-Ti-Zr-Ni Amorphous Alloys
Authors: Sordelet D.J. , Huang P. , Besser M.F. , Lepecheva E. 
Published: July 2021

Abstract
A brief feasibility study was performed to produce thermal spray coatings using gas atomized powders of Cu47Ti34-xZr11Ni8Six, where x=0 and 1. These alloys have previously been shown to be capable of forming metallic glasses having thick (1-2 cm) cross sections because they can be cooled from the melt at relatively low cooling rates (e.g., 100-102Ks-1). The properties of these metallic glasses include high strength, high elasticity and high fracture toughness. Amorphous plasma arc sprayed coatings were produced which were close in composition to the starting powders, and exhibited comparable glass transition and crystallization behavior. The amorphous structure of the as-sprayed coatings was used as a source for forming a range of partially devitrified and fully crystallized structures. The average hardness of the coatings increased from around 6 GPa to near 10 GPa as the degree of crystallization increased.
An Electromagnetic Acceleration Plasma Generator for Titanium Nitride Reactive Spray Coatings
Authors: Shibata T. , Tahara H. , Yasui T. , Kagaya Y. , Yoshikawa T. 
Published: July 2021

Abstract
Electromagnetic acceleration plasma generators, which are called Magneto-Plasma-Dynamic (MPD) arcjet generators, can produce higher-velocity, higher-temperature and higher-density plasmas than those of conventional thermal plasma torches, because MPD arcjet plasma is efficiently accelerated by electromagnetic body forces in MW-class input power operation. These properties are effective for deposition of rigid coatings adhering strongly to substrate surfaces. In the present study, we newly developed an ablation type MPD arcjet generator for titanium nitride (TiN) reactive spray coatings. The coatings were deposited onto steel substrate. The phase structure and the composition of the coatings were analyzed by means of scanning electron microscopy (SEM) and X-ray diffraction (XRD), and their Vickers hardness were measured. These analyses showed that the MPD spray process could successfully form dense and uniform titanium nitride coatings. The properties of the titanium nitride coatings were highly sensitive to the titanium cathode diameter and discharge current.
The Optimizing of the Superficial Cold-Burst Hardening Process of the Inner Cylindrical Metallic Surfaces by Knocking with Centrifuged Balls
Authors: Bulancea D. , Bulancea V. , Alexandru I. , Condurache D. 
Published: July 2021

Abstract
The metallic interior surfaces with cylindrical symmetry have been processed by knocking them with centrifuged balls. The first author has designed the used processing tool and it has been carried out under his instructions. There have been processed cast iron and carbon steel samples, using 80 different combinations for the process parameters: axial advance S, tangential rotation speed of the processed piece V, and the impact force F between the balls and the processed surface. Using the measured values of roughness Ra, Vickers microhardness HV and of the depths of cold-hardening h, we have achieved and used an optimizing computer program for the qualitative parameters of the cold-hardening process, i.e. Ra, HV and h. Also, we found optimal solutions for the processing regime. The study establishes the ability to increase the mechanical characteristics of the turned out metallic surfaces, thus taking out any further mechanical, thermal and/or chemical superficial processing. The results of the current study allow a correct choice of the processing regimes for different materials with similar bulk properties.
Performance of HVOF-Sprayed Carbide Coatings in Aqueous Corrosive Environments
Authors: Simard S. , Arsenault B. , Laul K. , Dorfman M.R. 
Published: July 2021

Abstract
The HVOF technology is well known to provide a wide variety of coating materials having excellent performance characteristics under different aggressive conditions such as wear, erosion by impact of particle and corrosion. Carbides, as a family, constitute a big segment of materials used by the thermal spray industry. Although their material properties may be well known since they are often used in wear or corrosive-wear industrial applications, aqueous corrosion of such coatings are not well characterized. Moreover, thermal spray process technology being in constant evolution, past literature on these coatings may not be directly applicable as newer produced coatings have higher adhesive and cohesive strength. Recent technology allows a better control on density and oxides content that are important parameters to consider for corrosion applications. The success of a coating is related to judicious material selection for various applications. However, the choice of the starting materials for producing a coating is often difficult since there is a lack of data on the corrosion performance of thermal spray coatings. The present paper addresses the performance of various carbide HVOF coatings in terms of corrosion rate and degradation mode in two corrosive environments — HCl and HNO3. Behavior of the coatings is compared using bulk SS316 and SS316 HVOF coating as a benchmark.
Arc Spraying for the Production of Multi-Component Zinc Anodes for Corrosion Protection of Concrete Structures
Authors: Knepper M. , Melzer A. , Spriestersbach J. , Wisniewski J. , Winkels A. 
Published: July 2021

Abstract
Structural damage in concrete structures caused by corrosion is widespread and demand comprehensive repair work. The additional installation of an active corrosion protective systems for structures being located in unfavourable conditions is imperative. Thermally sprayed coatings serving as anode have been adapted from the cathodic protection of steel. These systems have gained attention as they offer advantages in efficiency and lower cost. Thermally sprayed zinc coatings are applied to new steel reinforced concrete structures or those which are subject to re-structuring. In this contribution, the capability of various systems is examined by field tests in a marine structure and in different laboratory tests under natural and under accelerated conditions.
Near Net Shape Spray Forming—Metals
Authors: McKechnie T. 
Published: July 2021

Abstract
Near net shape spray forming technologies have matured into viable manufacturing techniques. Spray forming can be accomplished with many different thermal spray technologies yielding a range of materials with different properties. Monolithic materials, composite materials, and multi-layer materials have all been made. Mechanical properties comparable to cast versions of the parent material are achievable for some materials and processes. Tailored properties can also be achieved for such characteristics as high hermeticity, thermal protection, electrical isolation, wear resistance, etc. A review of materials and properties is presented.
Characteristics and Potential Application of Thermally Sprayed Thin Film Coatings
Authors: Loch M. , Barbezat G. 
Published: July 2021

Abstract
LPPS Thin Film is a new technology for the production of thin functional coatings. The coatings produced can fill the well known gap of coating thickness between conventional thin films (PVD, CVD and others) and conventional thermally sprayed coatings (Plasma, HVOF and others). The application is successful, if the advantages of the new technology (large areas can be dense coated within a very short time) are combined with the specific properties of thermally sprayed coatings to the benefit of the intended application. Beside the technology of LPPS Thin Film and it's characteristics the paper will summarise important properties of Alumina described in the literature and present some corresponding properties of Aluminium oxide coatings produced by LPPS Thin Film.
Hard Chrome Replacement and Other Thermal Spray Applications in the Chilean Navy
Authors: Streeter J. , Sampson E.R. 
Published: July 2021

Abstract
Naval ship components are subject to extreme operating conditions while at sea, either during regular sailing periods and/or during training exercises. The Chilean Navy has employed thermal spray technology since the early 1960 decade. By setting up a joint cooperative program between the Chilean Navy industry and suppliers, it has been possible to start regaining confidence in thermal spraying and positioning the same as a "must" technology in regular naval maintenance work. This article presents a description of the Naval Components Reclamation Program and discusses the processes involved in hard chrome plating replacement in naval components. It provides a review of characteristic thermal spray applications developed by the Joint Naval Components Reclamation Program.
Evaluation of CeSZ Thermal Barrier Coatings for Diesels
Authors: Huang P.J. , Swab J.J. , Patel P.J. , Chu W.S. 
Published: July 2021

Abstract
The development of thermal barrier coatings (TBCs) for diesel engines has been driven by the potential improvements in engine power and fuel efficiency that TBCs represent. TBCs have been employed for many years to reduce corrosion of valves and pistons because of their high temperature durability and thermal insulative properties. There are research programs to improve TBCs wear resistance to allow for its use in tribologically intensive areas of the engine. This paper will present results from tribological tests of ceria stabilized zirconia (CeSZ). The CeSZ was applied by atmospheric plasma spray process. Various mechanical and thermal properties were measured including wear, coefficient of thermal expansion, thermal conductivity, and microhardness. The results show the potential use of CeSZ in wear sensitive applications in diesel applications. Keywords: Thermal Barrier Coating, Diesel Engine, Wear, Thermal Conductivity, and Thermal Expansion
The Effect of HFPD Thermally Sprayed WC-Co Coatings on the Fatigue Behavior and Deformation of Al 2024-T4
Authors: Ibrahim A. , Berndt C.C. 
Published: July 2021

Abstract
The effect of high frequency pulse detonation (HFPD) and HVOF thermally sprayed WC-Co coatings on the high cycle fatigue (HCF) behavior of 2024-T4 aluminum was investigated. The fatigue life distributions of specimens in the polished and coated conditions are presented as a function of the probability of failure. The monotonic and cyclic deformation behaviors of the as-received and as-coated specimens were investigated. The conclusions show that, (i) the HFPD sprayed specimens exhibited slightly higher fatigue lives compared to the uncoated specimens, (ii) the HVOF sprayed specimens exhibited significantly higher fatigue lives compared to the uncoated specimens, and (iii) the as-coated specimen was cyclically stable.
Development and Performance Evaluation of Thick Air Plasma Sprayed Thermal Barrier Coatings
Authors: Mutasim Z.Z. , Nava Y.L. 
Published: July 2021

Abstract
Air plasma sprayed thermal barrier coatings have been widely used to reduce metal wall temperatures of industrial gas turbine combustor liners. Thermal barrier coatings provide thermal gradients, with the goal of reducing the liner wall temperature to acceptable levels as a result of their low thermal conductivity. A typical thermal barrier coating consists of a 0.1-0.2 mm MCrAlY bond coating and a 0.25-0.35 mm thick 8 wt.% yttria stabilized zirconia ceramic top coating. A method to increase thermal barrier coating effectiveness is the application of thicker ceramic coatings. Development and performance testing of 0.5-0.8 mm thick ceramic coatings are discussed in this paper. Cyclic oxidation tests that simulate industrial gas turbine environments were conducted. Thermal barrier coating degradation-mechanisms were determined from microstructural evaluation of thermally exposed samples.
X-Rays and TEM Characterization of Nanocrystalline Iron Aluminide Coatings Prepared by HVOF Thermal Spraying
Authors: Grosdidier T. , Liao H.L. , Tidu A. 
Published: July 2021

Abstract
FeAl iron-aluminide based materials with the ordered B2 structure are excellent candidates for use in high temperature applications because of the combination of good mechanical properties, low density, low cost and availability of raw materials, and improved oxidation resistance. The aim of this article is to produce an ultra-fine grained FeAl coating by HVOF thermal spraying of milled powders and characterize the fine scale features of its microstructure. Comparison is made with a more conventional coating obtained by projection of powders obtained by atomization. Starting powders and coatings were investigated using X-ray diffraction and transmission electron microscopy. It was observed that the coating obtained from milled powders had a microstructure essentially characterised by a nanometer grain size and the presence of a disordered FeAl phase.
Gdzie kończy się norma (…) a zaczyna patologia . Kilka uwag o niepoczytalności na gruncie wielomodelowego definiowania „zdrowia psychicznego” w świetle rozważań Georga E. Vaillant’a
Authors: Żywucka - Kozłowska Elżbieta Agata 
Published: July 2021

Powszechne rozumienie normalności sprowadza się do tego, że nic nie jest odmienne, inne i mieści się w ramach zwyczajności. Patologia w tym układzie znajduje się poza obszarem owej normalności, utożsamianej ze zwyczajnością. W niniejszym opracowaniu podjęto próbę ustalenia determinantów patologii jak i normy w perspektywie prawa karnego materialnego, psychologii jak i psychiatrii. Wydawać się może, że w tym obszarze przedstawiono już wszystkie argumenty „ za i przeciw”, oparte na przepisach prawa jak i poglądach doktryny. Pomiędzy jednym a drugim pojęciem ( poczytalności i niepoczytalności jak też normy i patologii) , nie ma próżni. Są bowiem stany , których istotą jest brak stałości w szerokim tego określenia rozumieniu, jak i też stany takie, które z jednej strony mieszczą się w obszarze patologii z punktu widzenia psychiatrii i psychologii, zaś w perspektywie prawa nie stanowią przesłanki niepoczytalności czy poczytalności ograniczonej