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Full-Text Articles in Engineering
Performance Of Columnar 7-8 Wt% Ysz Coatings On Platinum Aluminide Bondcoats, Christopher Petorak
Performance Of Columnar 7-8 Wt% Ysz Coatings On Platinum Aluminide Bondcoats, Christopher Petorak
Thermal Barrier Coatings IV
No abstract provided.
High Temperature Thermodynamic, Mechanical And Kinetic Properties From First Principles, Anton Van Der Ven
High Temperature Thermodynamic, Mechanical And Kinetic Properties From First Principles, Anton Van Der Ven
Thermal Barrier Coatings IV
No abstract provided.
Demonstration Of Two Novel Methods For Residual Stress Management On Nial Bond Coats, Markus Krottenthaler, Karsten Durst, Mathias Goken
Demonstration Of Two Novel Methods For Residual Stress Management On Nial Bond Coats, Markus Krottenthaler, Karsten Durst, Mathias Goken
Thermal Barrier Coatings IV
No abstract provided.
Prediction Of The Cyclic Durability As A Function Of Cycle Duration And Temperature Of An Air Plasma Sprayed Coating Using Inelastic Strain, Eric H. Jordan, Shayan Ahmadian, Maurice Gell
Prediction Of The Cyclic Durability As A Function Of Cycle Duration And Temperature Of An Air Plasma Sprayed Coating Using Inelastic Strain, Eric H. Jordan, Shayan Ahmadian, Maurice Gell
Thermal Barrier Coatings IV
A detailed study of the failure mechanisms in an APS TBC was carried out involving over 1000 micrographs. As a result the kinetics of oxidation and rumpling were characterized. In addition it was found that the failure was always within the ceramic caused by progressive cracking. At approximately half the spallation life, crack linking became the dominant growth mode for cracks. This pattern of damage remained constants over the temperature range of 1066 °C to 1149 °C and for cycle durations of 0.5 hours to 50 hours. The change in temperature resulted in a variation in spallation life of a …
Manufacture Of Silicide Coatings For The Protection Of Niobium Alloys Against High Temperature Oxidation, M. Vilasi, S. Matheieu, S. Knittel, L. Portebois, T. Katrina, C. Rapin, C. Petitjean, P. J. Panteix, S. Drawin
Manufacture Of Silicide Coatings For The Protection Of Niobium Alloys Against High Temperature Oxidation, M. Vilasi, S. Matheieu, S. Knittel, L. Portebois, T. Katrina, C. Rapin, C. Petitjean, P. J. Panteix, S. Drawin
Thermal Barrier Coatings IV
At the moment, silicide coatings provide the best protection against high temperature oxidation for niobium alloys. These are envisaged for replacing nickel base alloys currently used in the hot section of turbo-engines. Silicides confer higher protectiveness to Nb base system when compared to the environmental resistance presented by Nb alloys coated with aluminides. One major advantage of silicides is probably the great number of possibilities for modifying their composition as well as their crystallographic structure. Thus, many elemental substitutions were performed over the past 20 years in order to optimize their performances in terms of oxidation resistance. The works performed …
Ceramic Matrix Composite Environmental Protection Strategies, Bradley Richards, Hengbei Zhao, Haydn Wadley
Ceramic Matrix Composite Environmental Protection Strategies, Bradley Richards, Hengbei Zhao, Haydn Wadley
Thermal Barrier Coatings IV
No abstract provided.
Lifetime Of Environmental/Thermal Barrier Coatings Deposited On An Nb/Nb5si3- Based Alloy With Feb-Modified M7si6-Based Bond Coat, Reinhold Braun, Annika Lange, Uwe Schulz, Leo Portebois, Stephane Mathieu, Michael Vilasi, Stefan Drawin
Lifetime Of Environmental/Thermal Barrier Coatings Deposited On An Nb/Nb5si3- Based Alloy With Feb-Modified M7si6-Based Bond Coat, Reinhold Braun, Annika Lange, Uwe Schulz, Leo Portebois, Stephane Mathieu, Michael Vilasi, Stefan Drawin
Thermal Barrier Coatings IV
To enhance the performance of aircraft engines, high temperature materials are required being capable to operate at temperatures significantly higher than the temperature limit of about 1150°C approached for Ni-based superalloys currently employed. Nb/Nb5Si3-based composites are promising candidates for turbine engine applications at temperatures up to 1300°C, exhibiting balanced mechanical properties and reduced density compared to Ni-based superalloys [1]. To use these composites in gas turbine combustion atmosphere, environmental/thermal barrier coatings (E/TBCs) are required to protect them against heat, degradation in flowing water vapour and chemical attack of calcium-magnesium-alumino-silicate (CMAS).
Simulations Of Fracture In Coatings With Complex Microstructures, Mathew R. Begley, William Pro, Rone Kwei Lim, Linda Petzold
Simulations Of Fracture In Coatings With Complex Microstructures, Mathew R. Begley, William Pro, Rone Kwei Lim, Linda Petzold
Thermal Barrier Coatings IV
No abstract provided.
Lifetime Assessment Tools For Thermal Barrier Systems, Jean Louis Chaboche, Frederic Feyel, Martine Poulain, Noemie Rakotamalala, Arjen Roos, Jean Roch Vaunois, Arnaud Longuet, Pascale Kanaoute
Lifetime Assessment Tools For Thermal Barrier Systems, Jean Louis Chaboche, Frederic Feyel, Martine Poulain, Noemie Rakotamalala, Arjen Roos, Jean Roch Vaunois, Arnaud Longuet, Pascale Kanaoute
Thermal Barrier Coatings IV
No abstract provided.
Reliable Measurement Of Mechanical Tbc Properties For Quality Control And Life Prediction, Peter Wittig, Stefan Lampenscherf, Uwe Rettig, Matthias Oechsner
Reliable Measurement Of Mechanical Tbc Properties For Quality Control And Life Prediction, Peter Wittig, Stefan Lampenscherf, Uwe Rettig, Matthias Oechsner
Thermal Barrier Coatings IV
No abstract provided.
High Temperature Environmental Resistance Of Mo-Si-B Alloys And Coatings, John H. Perepezko
High Temperature Environmental Resistance Of Mo-Si-B Alloys And Coatings, John H. Perepezko
Thermal Barrier Coatings IV
No abstract provided.
Mechanical Stability Limits Of Bi-Layer Thermal Barrier Coatings, Mario Rudolphi, Mathias Galetz, Michael Schutze, Martin Frommherz, Alfred Scholz, Mathias Oechsner, Emine Bakan, Robert Vassen, Werner Stamn
Mechanical Stability Limits Of Bi-Layer Thermal Barrier Coatings, Mario Rudolphi, Mathias Galetz, Michael Schutze, Martin Frommherz, Alfred Scholz, Mathias Oechsner, Emine Bakan, Robert Vassen, Werner Stamn
Thermal Barrier Coatings IV
Thermal barrier coatings based on yttria stabilized zirconia (YSZ) have reached a state in development, where a further increase in lifetime and/or maximum operating temperature has become more and more difficult. Nevertheless, the demand for even higher operating temperatures is persisting, and it is pushing the YSZ-based thermal barrier coatings to and beyond their limit. Especially phase instabilities of YSZ at temperatures above 1200°C lead to a fast deterioration of the ceramic top coating. Consequently, the search for new materials with low thermal conductivity, relatively low coefficient of thermal expansion and phase stability at temperatures well above 1200°C was started, …
Specific Failure Modes Of Ni-Base Superalloys And Tbcs Under A Simulated Combustion Gas Atmosphere, Mazaku Okazaki, Satoshi Yamagishi, Y. Hayashi
Specific Failure Modes Of Ni-Base Superalloys And Tbcs Under A Simulated Combustion Gas Atmosphere, Mazaku Okazaki, Satoshi Yamagishi, Y. Hayashi
Thermal Barrier Coatings IV
No abstract provided.
Nasa’S Advanced Environmental Barrier Coatings Development For Sic/Sic Ceramic Matrix Composites: Understanding Cmas Degradations And Resistance, Dongming Zhu
Thermal Barrier Coatings IV
No abstract provided.
Yttrium Oxide A Candidate Material For Environmental And Thermal Barrier Coatings, Peter Mechnich, Wolfgang Braue, Nadine K. Eils, Stefan Hackemann, Ravisankar Naraparaju
Yttrium Oxide A Candidate Material For Environmental And Thermal Barrier Coatings, Peter Mechnich, Wolfgang Braue, Nadine K. Eils, Stefan Hackemann, Ravisankar Naraparaju
Thermal Barrier Coatings IV
No abstract provided.
Cmas Degradation And Implications For Coating Design, Arlos Levi
Cmas Degradation And Implications For Coating Design, Arlos Levi
Thermal Barrier Coatings IV
No abstract provided.
Aps Tbc Life Prediction - Impact Of Manufacturing Variations, Stefan Lampenscherf, Ramesh Subramanian
Aps Tbc Life Prediction - Impact Of Manufacturing Variations, Stefan Lampenscherf, Ramesh Subramanian
Thermal Barrier Coatings IV
No abstract provided.
Solubility Of Oxides From Zro2-Y2o3 And Zro2-Nd2o3 Systems In A Molten Cas. Selection Of A Thermal Barrier Composition Resistant To Cas Infiltration, Marie-Helene Vidal-Setif, Catherine Rio, Odile Lavigne, Nezha Chellah, Michel Vilasi, Cristophe Rapin, Carine Petitjean, Pierre Jean Panteix
Solubility Of Oxides From Zro2-Y2o3 And Zro2-Nd2o3 Systems In A Molten Cas. Selection Of A Thermal Barrier Composition Resistant To Cas Infiltration, Marie-Helene Vidal-Setif, Catherine Rio, Odile Lavigne, Nezha Chellah, Michel Vilasi, Cristophe Rapin, Carine Petitjean, Pierre Jean Panteix
Thermal Barrier Coatings IV
No abstract provided.
Columnar Structured Thermal Barrier Coatings By Thermal Spray Methods, Robert Vassen, Nadine Schlegel, Stefan Rezanka, Georg Mauer, Emine Bakan, Daniel Mack
Columnar Structured Thermal Barrier Coatings By Thermal Spray Methods, Robert Vassen, Nadine Schlegel, Stefan Rezanka, Georg Mauer, Emine Bakan, Daniel Mack
Thermal Barrier Coatings IV
No abstract provided.
Stress And Crack Monitoring During Plasma Spraying Of Tbc, Seiji Kuroda, Xiancheng Zhang, Makoto Watanabe, Kaita Ito, Manabu Enoki
Stress And Crack Monitoring During Plasma Spraying Of Tbc, Seiji Kuroda, Xiancheng Zhang, Makoto Watanabe, Kaita Ito, Manabu Enoki
Thermal Barrier Coatings IV
Two types of process monitoring techniques are compared and discussed in this presentation. The first one is in-situ curvature monitoring, by which it was possible to evaluate the stress evolution during plasma spraying and separately identify the sources of stresses, i.e., the quenching stress and thermal stress as shown in Fig.1 (a). By changing the spraying parameters, it was possible to prepare specimens at largely different deposition temperatures, which resulted in significantly different levels of residual stresses. Also, it was found that the mechanical properties of the obtained YSZ coatings such as the elastic modulus are strongly dependent on the …
New Class Of Refractory Ceramics For Thermal Barrier Coatings, Wei Pan
New Class Of Refractory Ceramics For Thermal Barrier Coatings, Wei Pan
Thermal Barrier Coatings IV
No abstract provided.
Suspension Plasma Sprayed Thermal Barrier Coatings, Per Nylen, Nicholas Curry, Ashish Ganvir, Nicolaie Markocsan
Suspension Plasma Sprayed Thermal Barrier Coatings, Per Nylen, Nicholas Curry, Ashish Ganvir, Nicolaie Markocsan
Thermal Barrier Coatings IV
No abstract provided.
Effect Of Bondcoat Roughness On Lifetime Of Aps-Tbc Systems In Dry And Wet Gases, W.J. Quadakkers, D. Naumeko, P. Mor, W. Nowak, L. Singheiser
Effect Of Bondcoat Roughness On Lifetime Of Aps-Tbc Systems In Dry And Wet Gases, W.J. Quadakkers, D. Naumeko, P. Mor, W. Nowak, L. Singheiser
Thermal Barrier Coatings IV
Low pressure plasma spraying (LPPS) is a process commonly used for deposition of MCrAlY (M=Ni,Co) bondcoats for air plasma spray thermal barrier coatings (APS-TBCs). LPPS produces bondcoats with a high roughness and good oxidation resistance, which are known to play a key role for long lifetimes of APS-TBC’s. An alternative process for the bondcoat deposition is high velocity oxy-fuel (HVOF), which is substantially cheaper than LPPS but even with well optimized spraying parameters generates intrinsically lower bondcoat roughness. In the present work it is shown that a bi-layer MCrAlY-bondcoat consisting of an HVOF-base layer and an upper, thin APS-flashcoat of …
High-Temperature Ceramic Coatings Used In Aero Engine Environments, David Rickerby, Paul Morrell, Matthew Hancock
High-Temperature Ceramic Coatings Used In Aero Engine Environments, David Rickerby, Paul Morrell, Matthew Hancock
Thermal Barrier Coatings IV
This paper reviews the role of ceramic coatings technology in the hot sections of modern gas turbine engines by contrasting the role of surface engineering and coatings away from secondary reliance (i.e. the coating extending the life of the component and when the coating is lost or fails there is still an appreciable remnant life of the component) to prime reliance where the failure of the coating would result in a rapid failure of the component. To illustrate this change in design philosophy, the coating systems deployed in the HP turbine module in both shrouded and unshrouded configurations are discussed …
The Effect Of Exposure Variables On The Development Of Alumina Scales, Gerry Meier
The Effect Of Exposure Variables On The Development Of Alumina Scales, Gerry Meier
Thermal Barrier Coatings IV
The early development of an adherent, slowly-growing α-alumina film on the bond coat is a critical factor in the life of a thermal barrier coating system. This presentation will include results of recent experiments at the University of Pittsburgh and reanalysis of older data from the literature on the selective oxidation of aluminum from Ni-base alloys. The following aspects of alumina scale establishment will be addressed: • The manner by which alloy composition affects the kinetics and mechanism of the transition of alumina from the θ to the α polymorph. • The influence of the θ to α transition on …
Application Of Eq Bond Coat To Eb-Pvd Tbc Systems, Kazuhide Matsumoto, Kyoko Kawagishi, Yutaka Koizumi, Hiroshi Harada
Application Of Eq Bond Coat To Eb-Pvd Tbc Systems, Kazuhide Matsumoto, Kyoko Kawagishi, Yutaka Koizumi, Hiroshi Harada
Thermal Barrier Coatings IV
To prevent the formation of SRZ in the log-time high-temperature exposure of the turbine blades, thermodynamically equilibrium phase such as gamma-prime phase of the substrate is use as an oxidation-resistant bond coat. The previous study clarified that this EQ coating shows excellent interface stability and it does not degrade mechanical strength due to the SRZ formation. In this study, TBC life test of EB-PVD ceramics coated EQ coating is investigated with other conventional MCrAlY coatings. The 4th and 5th generation superalloys are used for substrates. About 150 μm thick of EQ coating, conventional NiCoCrAlY and CoNiCrAlY coating are deposited by …
Design Constraints And Higher Temperature Intermetallic Bond Coatings, T.M. Pollock, D. Jorgensen, R.W. Jackson, M. He, A. Suzuki, D. Lipkin
Design Constraints And Higher Temperature Intermetallic Bond Coatings, T.M. Pollock, D. Jorgensen, R.W. Jackson, M. He, A. Suzuki, D. Lipkin
Thermal Barrier Coatings IV
Bond coat interlayers in thermal barrier coating (TBC) systems must perform reliably in the complex thermal, chemical and mechanical environment of the turbine engine. To achieve higher temperatures and /or longer cyclic lives, a spectrum of intrinsic failure modes must be suppressed. Failure may occur at the bond coat – thermally grown oxide (TGO) interface, at the TGO-TBC interface or by oxidation-enhanced propagation of cracks from the coating into the substrate. Models for the failure processes suggest that bond coatings should possess improved high temperature strength (creep resistance), low oxide growth stresses and high interfacial toughnesses. Oxide growth stresses have …
A Recent History Of Thermal Barrier Coatings For Aero-Propulsion Applications, Brian Hazel, Michael J. Maloney
A Recent History Of Thermal Barrier Coatings For Aero-Propulsion Applications, Brian Hazel, Michael J. Maloney
Thermal Barrier Coatings IV
Thermal barrier coatings for aero-propulsion operation have been in use since the 1960s. These thermal barrier coatings are composed of an oxidation resistant metallic base layer and a thermally resistant ceramic top layer. The development and implementation of advances in both the metallic base and the ceramic top layer will be explored. The evolution has included performance and durability improvements, process advances, and understanding and evolution of failure modes. More recent efforts have focus on future challenges for thermal barrier coatings to meet ever increasing operating temperature demands of future applications.
Potential Impacts Of Alternative Fuels On The Evolution And Stability Of Turbine Hot- Section Materials, Daniel Mumm, Timothy Montalbano, Matthew Sullivan
Potential Impacts Of Alternative Fuels On The Evolution And Stability Of Turbine Hot- Section Materials, Daniel Mumm, Timothy Montalbano, Matthew Sullivan
Thermal Barrier Coatings IV
This talk will provide an overview of a research program focused on evaluating the potential impacts of alternative fuels (coal-derived syngas, high-hydrogen content fuels, bio-derived synthetics) on the degradation of hot-section materials through accelerated attack of protective thermally grown oxides (TGOs) and thermal barrier coating (TBC) systems. A primary focus is the role of elevated water vapor levels, volatility, and vapor phase transport processes on the evolution of TGO and TBC systems. Materials exposure studies will be described that demonstrate that differing simulated combustion environments affect both the growth rate and the stability of the resulting thermally grown oxides. In …
Cold Spray Bond Coats Structure And Oxidation Behavior, A. Barth, S. Kudapa, W. Wong, K. Onizawa
Cold Spray Bond Coats Structure And Oxidation Behavior, A. Barth, S. Kudapa, W. Wong, K. Onizawa
Thermal Barrier Coatings IV
No abstract provided.