Tailored Solutions for Off-Shore Applications by Plazjet Sprayed Coatings

1997 ◽  
Author(s):  
F. Ladru ◽  
E. Lugscheider ◽  
H. Jungklaus ◽  
C. Herbst ◽  
I. Kvernes
Keyword(s):  
Process Control ◽  
Thermal Spraying ◽  
Temperature Stability ◽  
Hard Coatings ◽  
High Temperature Stability ◽  
Coating Quality ◽  
Large Structures ◽  
Wide Range ◽  
Sprayed Coatings ◽  
Suitable Process

Abstract For very large structures and parts in critical environments, a materials solution often cannot be found by using one material. The specific desired properties for those structures, like stiffness, ductility, high temperature stability, corrosion resistance, etc. are difficult to fulfill with only one material. In this case a solution may be found by using coatings and design their specific properties to replenish each other by their combination. The Thermal Spraying processes offer the necessary flexibility of producing thin to thick, ductile, soft to hard coatings while due to the wide range of process temperatures it is possible to process a wide range of materials, both as coating and structure. In this paper the some recent and important developments in Thermal Spraying to produce coatings for technical demanding structures will be described. These developments consist of High Power Plasma Spraying, powder- and process control development. To ensure process consistency during long spraying times and to apply reproducible coating quality a suitable process control is of great importance and the development of temperature control by Pyrometry and Thermography will be presented. The example will be drawn according to the application of a coating on a ball valve for off-shore and ship diesel engine parts (piston and valve).

High-Temperature Spin-On Adhesives for Temporary Wafer Bonding

2007 ◽  
Vol 4 (3) ◽  
pp. 105-111 ◽  
Author(s):  
S. Pillalamarri ◽  
R. Puligadda ◽  
C. Brubaker ◽  
M. Wimplinger ◽  
S. Pargfrieder
Keyword(s):  
High Temperature ◽  
Wafer Bonding ◽  
Heat Dissipation ◽  
Temperature Stability ◽  
High Temperature Stability ◽  
Performance Requirements ◽  
Wide Range ◽  
Bonding Properties ◽  
Partial List ◽  
Wafer Thinning

Wafer thinning has been effectively used to improve heat dissipation in power devices and to fabricate flexible substrates, small chip packages, and multiple chips in a package. Wafer handling has become an important issue due to the tendency of thinned wafers to warp and fold. Thinned wafers need to be supported during the backgrinding process, lithography, deposition, etc. Temporary wafer bonding using removable adhesives provides a feasible route to wafer thinning. Existing adhesives meet only a partial list of performance requirements. They do not meet the requirements of high-temperature stability combined with ease of removal. This paper reports on the development of a wide range of temporary adhesives to be used in wafer thinning applications that use both novel and conventional bonding and debonding methods. We have developed a series of novel removable high-temperature spin-on adhesives with excellent bonding properties and a wide range of operating temperatures for bonding and/or debonding to achieve a better processing window.

Hexaaluminate Catalysts for Fuel Reforming

2008 ◽  
Author(s):  
Nicholas E. McGuire ◽  
Neal P. Sullivan ◽  
Robert J. Kee ◽  
Huayang Zhu ◽  
James A. Nabity ◽  
...  
Keyword(s):  
Flow Reactor ◽  
Exchange Process ◽  
Catalyst Support ◽  
Temperature Stability ◽  
Metal Exchange ◽  
High Temperature Stability ◽  
Fuel Reforming ◽  
Transmission Electron ◽  
Wide Range ◽  
Hexaaluminate Catalysts

Hexaaluminate catalysts offer excellent high-temperature stability compared to the equivalent metal-based catalysts. Their stability also lends well to use as a catalyst support. However, use of novel hexaaluminates is limited in fuel processing for fuel-cell applications. In this paper, we report on the performance of hexaaluminates as a catalyst support in the steam reforming of methane. The hexaaluminates are synthesized by a metal-exchange process using alumoxane precursors that enable a wide range of metal substitutions. Performance is evaluated using a unique stagnation-flow reactor that enables detailed probing of the boundary layer above the catalyst-impregnated stagnation surface. Experimental results are compared with models to understand fundamental reaction kinetics and optimize catalyst performance. RhSr-substituted hexaaluminates with a Rh impregnation are shown to yield the best performance. Scanning- and Transmission-Electron Microscopy are used to characterize the different types of hexaaluminates, and to examine the effect of aging on catalyst structure.

Stability of Nanometer-Thick Layers in Hard Coatings

MRS Bulletin ◽  
2003 ◽  
Vol 28 (3) ◽  
pp. 169-172 ◽  
Author(s):  
Scott A. Barnett ◽  
Anita Madan ◽  
Ilwon Kim ◽  
Keith Martin
Keyword(s):  
High Temperature ◽  
Elevated Temperatures ◽  
Temperature Stability ◽  
Hexagonal Wurtzite Structure ◽  
Thin Layers ◽  
Hard Coatings ◽  
High Temperature Stability ◽  
The Stability ◽  
Hardness Values ◽  
Thick Layers

AbstractThis article reviews two topics related to the stability of hard coatings composed of nanometer-thick layers: epitaxial stabilization and high-temperature stability. Early work on nanolayered hard coatings demonstrated large hardness increases as compared with monolithic coatings, but it was subsequently found that the layers interdiffused at elevated temperatures. More recently, it has been shown that nanolayers exhibit good stability at elevated temperatures if the layer materials are thermodynamically stable with respect to each other and are able to form low-energy coherent interfaces. This article discusses metal/nitride, nitride/nitride, and nitride/boride nanolayers that exhibit good high-temperature stability and hardness values that are maintained (or even increase) after high-temperature annealing. Epitaxial stabilization of nonequilibrium structuresin thin layers is a well-known phenomenon that has been applied to hard nitride materials. In particular, AlN, which crystallizes in the hexagonal wurtzite structure in bulk form, was stabilized in the rock-salt cubic structure in nitride/nitride nanolayers (e.g., AlN/TiN). These results and the current understanding of epitaxial stabilization in hard nanolayers are discussed.

scholarly journals Probing the Nanoscale Heterogeneous Mixing in a High-Performance Polymer Blend

Polymers ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 192
Author(s):  
Alexander Paul Fellows ◽  
Debashis Puhan ◽  
Janet S. S. Wong ◽  
Michael T. L. Casford ◽  
Paul B. Davies
Keyword(s):  
High Performance ◽  
Domain Boundary ◽  
Temperature Stability ◽  
Chemical Information ◽  
High Temperature Stability ◽  
Force Microscopy ◽  
Domain Structures ◽  
Wide Range ◽  
Physical Mixing ◽  
Cantilever Probes

The blend of polyetheretherketone (PEEK) and polybenzimidazole (PBI) produces a high-performance blend (PPB) that is a potential replacement material in several industries due to its high temperature stability and desirable tribological properties. Understanding the nanoscale structure and interface of the two domains of the blend is critical for elucidating the origin of these desirable properties. Whilst achieving the physical characterisation of the domain structures is relatively uncomplicated, the elucidation of structures at the interface presents a significant experimental challenge. In this work, we combine atomic force microscopy (AFM) with an IR laser (AFM-IR) and thermal cantilever probes (nanoTA) to gain insights into the chemical heterogeneity and extent of mixing within the blend structure for the first time. The AFM-IR and nanoTA measurements show that domains in the blend are compositionally different from those of the pure PEEK and PBI polymers, with significant variations observed in a transition region several microns wide in proximity to domain boundary. This strongly points to physical mixing of the two components on a molecular scale at the interface. The versatility intrinsic to the combined methodology employed in this work provides nano- and microscale chemical information that can be used to understand the link between properties of different length scales across a wide range of materials.

Hybrid Plasma Spraying —Discovering the Effects of Deposition Parameters

2021 ◽  
Author(s):  
Tomas Tesar ◽  
Radek Musalek ◽  
Jan Medricky ◽  
Jan Cizek ◽  
Frantisek Lukac ◽  
...  
Keyword(s):  
Plasma Spraying ◽  
Thermal Spraying ◽  
Hybrid Coatings ◽  
Deposition Parameters ◽  
Wide Range ◽  
Hybrid Plasma ◽  
Coating Formation ◽  
Liquid Feedstock ◽  
Multiple Case ◽  
Sprayed Coatings

Abstract Hybrid plasma spraying is emerging as the next potential technology leap in thermal spraying. The combination of high throughput and deposition rates of coatings sprayed from powders with the tailored functionality of liquid-feedstock sprayed coatings appears highly promising for a wide range of applications. Moreover, possible refined mixtures of different materials come readily with the utilization of multiple feedstocks with varying particle sizes. However, the practical aspects of hybrid coatings production are accompanied with several peculiarities not encountered when using distinct feedstocks. To deepen the understanding of this novel route, this paper presents fundamental hybrid coating formation principles and the effect of selected deposition parameters using multiple case-study material systems, such as Al2O3-YSZ, Al2O3-Cr2O3, and Al2O3-TiO2.

Tribological Requirements of Thermally Sprayed Coatings for Wear Resistant Applications

2000 ◽  
Author(s):  
S.D. Siegmann ◽  
O.C. Brandt ◽  
N.M. Margadant
Keyword(s):  
State Of The Art ◽  
Tribological Behavior ◽  
Thermal Spraying ◽  
Field Tests ◽  
Spray System ◽  
Wide Range ◽  
Thermally Sprayed Coatings ◽  
Chromium Replacement ◽  
Thermally Sprayed ◽  
Sprayed Coatings

Abstract During the last decades, improved understanding of tribological behavior of different material combinations led also to an intensified development of thermal spray applications. In the field of e.g. hard chromium replacement by thermal spraying, significant amount of work has been done and published world wide, however, the authors manly focused on only one tribological aspect like friction, abrasion, erosion, cavitation or corrosion, respectively. In real applications, often more than one of those factors influence the successful use of these coatings. Besides the bulk properties of the materials, the coating micro structure, which is strongly spray system dependent, needs to be considered and investigated. Higher functionality and reliability than conventional competitive coatings still has to be proved at laboratory scale and under field conditions for thermally sprayed coatings. This paper describes the state of the art of thermally sprayed coatings as alternatives for other coatings. Published literature data and a wide range of own tribological investigations and field tests, reveals the potential for other applications.

Evaluation and Application of Hard Coatings for Steam Turbine

2017 ◽  
Author(s):  
Liang Yan ◽  
Yujiro Nakatani ◽  
Masayuki Yamada ◽  
Toru Abe ◽  
Koichi Kitaguchi ◽  
...  
Keyword(s):  
High Temperature ◽  
Steam Turbine ◽  
Power Plants ◽  
Turbine Blades ◽  
Temperature Stability ◽  
Hard Coatings ◽  
High Temperature Stability ◽  
Creep Tests ◽  
Tialn Coating ◽  
Steam Turbine Blades

In order to improve solid particle erosion (SPE) resistance for steam turbine blades and nozzles, in corporation with Kobe Steel, Ltd., evaluation of hard coatings of TiN and TiAlN deposited by the Arc Ion Plating (AIP®) process was performed to verify applicability to an actual steam turbine. The results of high-temperature steam oxidation tests and room-temperature sand erosion tests showed that the TiAlN coating had high-temperature stability superior to that of the TiN coating, and erosion resistance far superior to that in the case of the conventional CrC thermal spray coating and boronizing treatment. High-temperature fatigue and creep tests showed that the characteristic strength of the blade material with the TiAlN coating was equal or superior to that of the base blade material. On the basis of the results of comprehensive evaluation, it was confirmed that the TiAlN hard coating has excellent applicability to an actual steam turbine and it was successfully applied to steam turbine blades of power plants in Japan.

scholarly journals High-Performance Temporary Adhesives for Wafer Bonding Applications

2006 ◽  
Vol 970 ◽  
Author(s):  
Rama Puligadda ◽  
Sunil Pillalamarri ◽  
Wenbin Hong ◽  
Chad Brubaker ◽  
Markus Wimplinger ◽  
...  
Keyword(s):  
High Performance ◽  
Heat Dissipation ◽  
Driving Forces ◽  
Three Dimensional ◽  
Temperature Stability ◽  
Thickness Variation ◽  
High Temperature Stability ◽  
Process Step ◽  
Wide Range ◽  
Wafer Thinning

ABSTRACTMyriad structures for stacking chips, power devices, smart cards, and thin substrates for processors have one thing in common: thin silicon. Wafer thinning will soon be an essential process step for most of the devices fabricated and packaged henceforth. The key driving forces for thinned wafers are improved heat dissipation, three-dimensional stacking, reduced electrical resistance, and substrate flexibility. Handling of thin and ultrathin substrates however is not trivial because of their fragility and tendency to warp and fold. The thinned substrates need to be supported during the backside grinding process and through the subsequent processes such as lithography, deposition, etc. Using temporary adhesives to attach the processed device wafer to a rigid carrier wafer offers an efficient solution. The key requirements for such materials are ease of application, coating uniformity with minimal thickness variation across the wafer, good adhesion to a wide variety of surfaces, thermal stability in processes such as dielectric deposition and metallization, and ease of removal to allow high throughput. An additional requirement for these materials is stability in harsh chemical environments posed by processes such as etching and electroplating. Currently available materials meet only a subset of these requirements. None of them meet the requirement of high-temperature stability combined with ease of removal. We have developed adhesives that meet a wide range of post-thinning operating temperatures. Additionally, the materials are soluble in industry-accepted safe solvents and can be spin-applied to required thicknesses and uniformity. Above all, the coatings can be removed easily without leaving any residue. This paper reports on the development of a wide range of temporary adhesives that can be used in wafer thinning applications while applying both novel and conventional bonding and debonding methods.

Binary and Ternary Nitrate Solar Heat Transfer Fluids

2013 ◽  
Vol 135 (2) ◽  
Author(s):  
Kevin Coscia ◽  
Tucker Elliott ◽  
Satish Mohapatra ◽  
Alparslan Oztekin ◽  
Sudhakar Neti
Keyword(s):  
Heat Transfer ◽  
Power Systems ◽  
Thermal Power ◽  
Temperature Stability ◽  
Ternary Mixtures ◽  
Heat Transfer Fluid ◽  
High Temperature Stability ◽  
Solar Heat ◽  
Heat Transfer Fluids ◽  
Wide Range

Current heat transfer fluids for concentrated solar power applications are limited by their high temperature stability. Other fluids that are capable of operating at high temperatures have very high melting points. The present work is aimed at characterizing potential solar heat transfer fluid candidates that are likely to be thermally stable (up to 500 °C) with a lower melting point (∼100 °C). Binary and ternary mixtures of nitrates have the potential for being such heat transfer fluids. To characterize such eutectic media, both experimental measurements and analytical methods resulting in phase diagrams and other properties of the fluids are essential. Solidus and liquidus data have been determined using a differential scanning calorimeter over the range the compositions for each salt system and mathematical models have been derived using Gibbs Energy minimization. The Gibbs models presented in this paper sufficiently fit the experimental results as well as providing accurate predictions of the eutectic compositions and temperatures for each system. The methods developed here are expected to have broader implications in the identification of optimizing new heat transfer fluids for a wide range of applications, including solar thermal power systems.

Phosphonitrilic Fluoroelastomers—A New Class of Solvent Resistant Polymers with Exceptional Flexibility at Low Temperature

1974 ◽  
Vol 47 (1) ◽  
pp. 32-47 ◽  
Author(s):  
G. S. Kyker ◽  
T. A. Antkowiak
Keyword(s):  
Low Temperature ◽  
Temperature Stability ◽  
High Temperature Stability ◽  
Solvent Resistance ◽  
Physical Strength ◽  
New Class ◽  
Wide Range ◽  
Lip Seals ◽  
Dry Mixing ◽  
Low Temperature Flexibility

Abstract Many commercial elastomers exhibit good solvent resistance and high temperature stability but have limited use at low temperature. Fluorosilicone, which exhibits good low temperature properties, is limited in many dynamic applications by its poor physical strength. Phosphonitrilic fluoroelastomers are being developed for applications which require solvent resistance, low temperature flexibility, and good physical strength over a broad range of service conditions. A brief description of the synthesis and characterization of these new polymers has been presented in the forms of chemical, chromatographical, spectroscopical, physical testing, and rheological studies. The main object of this paper has been to provide an introduction to the art of processing, vulcanization, and reinforcement of these elastomers to produce useful commercial items. These fluoroelastomers can be processed on conventional equipment for dry-mixing rubber. Vulcanization can be effected with either organic peroxides or sulfur-accelerator cure systems. These vulcanizates can be reinforced with silicas, carbon blacks, or silane-treated clays to give stocks with a wide range of modulus, strength, hardness, and service temperatures (−80 to 400° F) in many service fluids and atmospheres. The exceptional solvent resistance, low temperature flexibility, and wide temperature service range indicate that phosphonitrilic fluoroelastomers should find use in items such as O-rings, Arctic fuel hose, lip seals, gaskets, and vibration damping services.

Sign in / Sign up

Export Citation Format

Share Document