Preface for the International Thermal Spray Conference 2017.

Listings of the organizing committees for the United Thermal Spray Conference 1999.

Listings of the organizing committees for the International Thermal Spray Conference 2002.

Many CFD software packages are commonly used for the modeling of thermal plasma jets. Unfortunately, according to some recent results reported in the literature, one may notice that two different software products do not always provide similar results for a similar case. For example, PHOENICS and FLUENT were recently used in a single study and some abnormal differences were observed in the numerical predictions [1]. After some intensive search, the reasons were identified and are explained in the present paper: it appears that all Fluent built-in k-å type turbulence models have to be modified especially for high temperature flows. Since Fluent is now extensively used for the modeling of plasma jets, it was considered useful to report the required correction to the scientific thermal spray community and this is the purpose of the present paper.

Preface for the International Thermal Spray Conference 2014.

Preface for the International Thermal Spray Conference 2011.

Preface for the International Thermal Spray Conference 2010.

In line with the industrial trend of additive manufacturing, cold spray as a non-laser-based process is becoming increasingly important for many fields of application. For the evaluation of additive manufacturing of winding components made of copper for large electrical high-voltage machines, material and component properties such as electrical conductivity, mechanical load capacity and the component size that can be produced are of particular importance. In this context, the cold spray process offers advantages over laser-based additive manufacturing processes such as laser powder bed fusion (LPBF) or laser cladding by using the kinetic energy of the copper powder particles to generate particle bonding. To investigate the electrical conductivity as well as the mechanical load capacity of cold spray parts, specimens were machined out of cold sprayed bulk copper deposits. The characteristic values were obtained with regard to the direction of deposition, which is defined by the direction of the robot’s movement. Thus, for the investigation of the component properties, specimens were provided that had been produced both aligned lengthwise and crosswise as well as vertically to the direction of deposition. The results of the investigations show that both the electrical conductivity and the mechanical load capacity of the specimen have a strong dependency of the specimen orientation with respect to the direction of deposition. Furthermore, it could be shown that by increasing the deposition height, there is an increasing oxygen content in the sample material, combined with increasingly significant defect networks. These effects have a negative impact on the electrical conductivity as well as on the mechanical load capacity. As a conclusion, further need for investigation is identified in the optimization of the process parameters as well as in the deposition strategy for the additive manufacturing of large-volume components with cold spray.

Preface (in German and in English) for the United Thermal Spray Conference 1999.

In the present work, APS and HVOF processes have been used to prepare alumina (Al 2 O 3 ) and magnesium aluminate spinel (MgAl 2 O 4 ) coatings designed for electrical insulating applications. The microstructures and the phase compositions of the sprayed coatings were evaluated by microscopic and XRD analysis. The electrical characteristics electrical resistance, electrical resistivity and dielectric breakdown strength were investigated using different methods: direct current (DC) measurements, electrochemical impedance spectroscopy (EIS) and dielectric breakdown testing. The electrical resistance was measured at room temperature at different humidity levels. Differences in the insulating properties due to the different natures of the coating materials, microstructures and the measurement methods used for electrical characterisation are discussed.

Preface for the United Thermal Spray Conference 1997. Includes a publishing history for proceedings from previous thermal spray conference events.

The HVOF sprayed wear resistant hardmetal coatings with favourable sliding properties are suitable for increasing the lifetime of sliding applications, such as pistons of combustion engines, pumps and other hydraulic devices. In practice, the coatings face the problem of their interaction with other media, in the case of sliding wear usually lubricants. In the paper, the friction properties of five different HVOF sprayed coatings are evaluated by pin-on-disk test according to ASTM G-99 under dry and lubricated conditions and lubricated block-of-ring test according to ASTM G77. Several types of lubricants designed for combustion engines were used to compare their influence on coatings sliding wear behavior. Based on the results, the suitability of coatings for the application on the engines parts is discussed and the effect of counterpart material and different types of lubricants on the coefficient of friction and coatings wear rate is analyzed. It was confirmed, that the CrC-based coating are more suitable for the application under the condition corresponding to combustion engines, e.g. elevated temperature and steel counterpart, than the WC-based coatings. From the group of CrC-based coatings, the superior behavior was observed at the CrC-CoNiCrAlY coating, the matrix material of which offers further enhancement of the sliding wear behavior.

Preface for the International Thermal Spray Conference 2022.

Boiler tube failure is the number one source of forced outages in all coal-fired and biomass-fired power generation plants. It is estimated that plants lose approximately 6% of their power generation annually, due to boiler tube leaks. The major causes for premature tube failure are excessive fireside boiler tube erosion and corrosion caused by impact, abrasive wear, oxidation and molten corrosion of low eutectic alloys.

Listings of authors for the United Thermal Spray Conference 1999. The list includes affiliation information for each author.

To use the manifold possibilities that the arc spraying offers to deposit carbide layers, the knowledge of the particle characteristics are necessary. This work is focused on understanding the particle formation during arc spraying with cored wires. The influence of primary and secondary atomization gas on the particle formation as well as on the particle shape, particle dimension and grain size are analyzed. Melting behaviors of different cored wires under various spraying parameters are investigated. Correlations between coating properties and particle characteristics are established. Experimental approaches to determine the in-flight properties of the sprayed particles in combination with metallographic analyses were employed to establish these correlations.

Well known that high temperature corrosion resistance of thermal barrier coatings (TBC) may depend not only on chemical composition, thickness, the rate of formation of TGO layer, but also on the presence of post treatment. In this work we studied the influence of presence of post treatment on properties of TBC particularly on high temperature corrosion. TBC system were sprayed on Ni-based substrate and consists of HVOF NiCo-based bond coat (BC) and APS yttria-stabilized zirconia (YSZ) top coat. Thermal cycling test in the presence of corrosive environment was used to determine effect of post treatment presence. Before and after Thermal cycling test cross-section of specimens were studied by SEM and EDX analyzes. Preliminary results demonstrated that high temperature corrosion resistance of TBC with APS-top layer and HVOF-bond layer can be improved by applying post treatment.

This paper shows how in-flight particle diagnostics can be used to optimize parameter sets for new layer materials and to detect drift in the control of thermal spraying lines. It describes the equipment and methods used to measure the temperature, velocity, and diameter of spray particles in a plasma jet and explains how torch current, plasma gas composition, carrier and total gas flow, and stand-off distance are varied according to a statistical design plan to determine their effect. The results are presented in the form of process maps and data plots, from which several conclusions are drawn. Paper includes a German-language abstract.

Preface for the International Thermal Spray Conference 2004.

The practical application of bulk metallic glasses (BMGs) as structural materials is still restricted due to the intrinsic brittleness of BMGs although they have high hardness and strength and even pretty good toughness. As an alternative form of metallic glasses, amorphous coatings based on BMG systems can exactly overcome the drawback of BMGs, but carry forward the superiority in corrosion and wear resistance, thus exhibiting promising applications in surface engineering. However, the monolithic amorphous coatings faces new challenges, such as low adhesion strength and impact toughness. In this presentation, we present some new findings on the design of novel Fe-based amorphous composite coatings by HVOF technique. These include the add stainless steel ductile phase, hard ceramic particles and in-situ carbon phases into the amorphous coating, in addition to form laminar structural coatings. It will be shown that the second phase and their interface structure with amorphous matrix play important role in the resultant mechanical properties of the coatings. The combination of the good mechanical, physical and chemical properties warrants amorphous composite coatings to have extensive applications in industry in near future.