DOCSLIB.ORG

Design of Thermal Barrier Coatings Nicholas Curry Ii

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Design of Thermal Barrier Coatings Nicholas Curry Ii PhD Thesis Production Technology 2014 No.3 Design of Thermal Barrier Coatings nicholas curry ii University West SE-46186 Trollhättan Sweden +46 52022 30 00 www.hv.se © Nicholas Curry 2014 ISBN 978-91-977943-9-8 iii Acknowledgements It’s said that a PhD thesis is never really finished….only that time is called and the tools are put down…. So after five years, here is my unfinished work. I would first like to thank my supervisors at University West; Per Nylen and Nicolaie Markocsan. I’ve learned a great deal during the last few years and I really appreciate the huge degree of freedom at work. It’s been a pleasure to work with you both. To Stefan Björklund, I couldn’t have asked for a better guy to work with over the last few years. It’s been enlightening, entertaining and downright hilarious. Thank you! Thanks to Lars Östergren for all the support with the projects from Volvo/GKN and with arranging spraying and testing. To the people at the Production Technology Centre, past and present; a big thank you for keeping the office an entertaining place to work. You know who you are (again)! I’m grateful also to the staff at the GKN Thermal Spray Department for their work in all the projects and for providing a nice working environment during my time there. To my family, I couldn’t ask for more support over the years. That I’ve reached this point is thanks to you all. There are many people who have helped me get this far; too many to mention here. To them I can only say thank you. 17th of January 2014 iv v Populärvetenskaplig Sammanfattning Nyckelord: Kraftgenererande gasturbiner; Gasturbiner för flygmotorer; Termiska värmebarriärskikt; Plasmasprutning; Suspensionsplasmasprutning; Värmeledningsförmåga; Termisk utmattning; Termochock testning Termiska barriärbeläggningar (TBC s) används för att ge både värmeisolering och oxidationsskydd för olika gasturbinkomponenter som utsätts för höga temperaturer. Utvecklingen av gasturbiner både för kraftgenererings- och flygapplikationer har lett till konstruktioner där driftsförhållandena överskrider gränserna för de flesta konventionella konstruktionsmaterial. Det har därmed funnits en drivkraft att utveckla värmebarriärbeläggningar som möjliggöra en högre driftstemperatur. Fokus i denna avhandling har varit att skapa nya värmebarriärbeläggningar med lägre värmeledningsförmåga och längre livslängd än de beläggningar som används inom industrin idag. Arbetet har genomförts i två delar. Den första delen har ägnats åt värmebarriärbeläggningar för kraftgenererande applikationer. Beläggningarna har i denna del produceras med hjälp av atmosfärisk plasmasprutning (APS). Den andra delen av arbetet har dedikerats åt beläggningar både för industriella gasturbiner och för flygmotorkomponenter. Beläggningarna har i denna del skapats med suspensionsplasmasprutning (SPS). Rutten som vidtagits för att kunna uppnå målen avseende låg värmeisolering och livslängd hos beläggningarna har varit tvåfaldig. För det första har ett alternativt stabiliseringsmaterial valts för zirkoniumoxidsystemet i form av Dysprosiumoxid. För det andra har tillsatsmaterialets (pulvrets) morfologi inklusive processparametrar varierats för att skapa beläggningar med gynnsam porositet i sin mikrostruktur. Suspensionssprutning som har tillämpats i andra delen av arbetet är en ny teknik för vilken processparametrar och tillsatsmaterial ännu inte är kända. Fokus i arbetet har här därför varit att karakterisera beläggningarnas livslängd och termiska egenskaper som funktion av olika processparametrar och tillsatsmaterial. Resultaten från arbetet visar att dysprosiumoxid som alternativ stabilisator ger en minskad värmeledningsförmåga. Skillnaden i värmeledningsförmåga är liten vid rumstemperatur med bli signifikant vid höga temperaturer och vid längre driftstider. Dock tyder resultaten på att materialstabiliteten minskar vid mycket höga driftstemperaturer. Vägen där porositeten i det keramiska skikten förändrades, för t skapa signifikant lägre värmeledningsförmåga, visade sig ännu mer framgångsrik. vi När det gäller beläggningarnas livslängd, visade det sig att, jämfört med dagens industristandard, kan en dubbelt så lång termisk utmattningslivslängd uppnås genom att optimera porositeten i beläggningen. Den önskvärda porositeten kunde dels åstadkommas genom att tillsätta en polymer till tillsatsmaterialet. Polymeren skapar här globulära porer i kombination med delamineringar, en mikrostruktur som visade sig mycket motståndskraftig mot termisk utmattning. Suspensionsprutade beläggningar visade sig ha signifikant bättre egenskaper både avseende värmeledningsförmåga och termisk utmattning. Kolumnära mikrostrukturer kunde åstadkommas med hjälp av denna sprutteknik. Denna typ av mikrostruktur kan möjliggöra sprutning av töjningsresistenta beläggningar i framtidens i gasturbinmotorer. vii Abstract Title: Design of Thermal Barrier Coatings Keywords: Industrial Gas Turbine; Aero Turbine; Thermal Barrier Coating; Atmospheric Plasma Spraying; Suspension Plasma Spraying; Thermal Conductivity; Thermo-cyclic fatigue; Thermal Shock ISBN: 978-91-977943-9-8 Thermal barrier coatings (TBC’s) are used to provide both thermal insulation and oxidation protection to high temperature components within gas turbines. The development of turbines for power generation and aviation has led to designs where the operation conditions exceed the upper limits of most conventional engineering materials. As a result there has been a drive to improve thermal barrier coatings to allow the turbine to operate at higher temperatures for longer. The focus of this thesis has been to design thermal barrier coatings with lower conductivity and longer lifetime than those coatings used in industry today. The work has been divided between the development of new generation air plasma spray (APS) TBC coatings for industrial gas turbines and the development of suspension plasma spray (SPS) TBC systems. The route taken to achieve these goals with APS TBC’s has been twofold. Firstly an alternative stabiliser has been chosen for the zirconium oxide system in the form of dysprosia. Secondly, control of the powder morphology and spray parameters has been used to generate coating microstructures with favourable levels of porosity. In terms of development of SPS TBC systems, these coatings are relatively new with many of the critical coating parameters not yet known. The focus of the work has therefore been to characterise their lifetime and thermal properties when produced in a complete TBC system. Results demonstrate that dysprosia as an alternative stabiliser gives a reduction in thermal conductivity. While small at room temperature and in the as produced state; the influence becomes more pronounced at high temperatures and with longer thermal exposure time. The trade-off for this lowered thermal conductivity may be in the loss of high temperature stability. Overall, the greatest sustained influence on thermal conductivity has been from creating coatings with high levels of porosity. viii In relation to lifetime, double the thermo-cyclic fatigue (TCF) life relative to the industrial standard was achieved using a coating with engineered porosity. Introducing a polymer to the spray powder helps to generate large globular pores within the coating together with a large number of delaminations. Such a structure was shown to be highly resistant to TCF testing. SPS TBC’s were shown to have much greater performance relative to their APS counterparts in thermal shock life, TCF life and thermal conductivity. Columnar SPS coatings are a prospective alternative for strain tolerant coatings in gas turbine engines. ix Preface The research presented in this thesis has been carried out at the Production Technology Centre as part of the Thermal Spray research group of University West. Additional experimental work has been carried out at GKN Aerospace Engine Systems at the Thermal Spray Department. The first part of the research work has been performed as part of a larger research project into the development of new thermal barrier coating systems for gas turbine applications. Partners in the project were: GKN Aerospace Engine Systems, who have been responsible for some elements of coating production and providing materials support. Sulzer Metco, who have provided powders for the spray process. Siemens Industrial Turbomachinery, who have been responsible for lifetime testing and are considered as the end user of a future coating. University West, who have acted as overall co-ordinator of the project and carried out the majority of the sample production and evaluation. The second part of the research work has been in the evaluation and development of Suspension Plasma Spray (SPS) as a game changing technology in the production of TBC coatings for aero engine and industrial gas turbine components. The project partners were: Progressive Surface - who were responsible for SPS coating production Northwest Mettech Corp- provided SPS coatings Treibacher Industrie AG, who supplied suspension for the project and some elements of testing University West, who have provided the bulk of the coating evaluation and produced substrate with bond coat. x List of Appended Publications Paper 1- Next Generation TBC’s for Gas Turbine Applications Nicholas Curry, Nicolaie Markocsan, Xin-Hai Li, Aurélien Tricoire, Mitch Dorfman Journal of Thermal Spray Technology, Vol. 20, no. 1–2, pp. 108–115, Nov. 2010. Paper 2- Evaluation of Thermal Properties and Lifetime of Dysprosia Stabilised Thermal Barrier Coatings Nicholas Curry,
Load more

Recommended publications
  • Biofuels and Thermal Barrier: a Review on Compression Ignition Engine Performance, Combustion and Exhaust Gas Emission
    Biofuels and thermal barrier: A review on compression ignition engine performance, combustion and exhaust gas emission K. Masera, A. K. Hossain* Sustainable Environment Research Group (SERG), School of Engineering and Applied Science, Aston University, Aston Triangle, Birmingham B4 7ET, UK Abstract The performance of an internal combustion engine is affected when renewable biofuels are used instead of fossil fuels in an unmodified engine. Various engine modifications were experimented by the researchers to optimise the biofuels operated engine performance. Thermal barrier coating is one of the techniques used to improve the biofuels operated engine performance and combustion characteristics by reducing the heat loss from the combustion chamber. In this study, engine tests results on performance, combustion and exhaust emission characteristics of the biofuels operated thermal barrier coated engines were collated and reviewed. The results found in the literature were reviewed in three scenarios: (i) uncoated versus coated engine for fossil diesel fuel application, (ii) uncoated versus coated engine for biofuels (and blends) application, and (iii) fossil diesel use on uncoated engine versus biofuel (and blends) use on coated engine. Effects of injection timing, injection pressure and fuel properties on thermal barrier coatings were also discussed. The material type, thickness and properties of the coating materials used by the research community were presented. The effectiveness and durability of the coating layer depends on two key properties:
    [Show full text]
  • Cyclic Durability of Thermal Barrier Coatings Subject to CMAS Attack Alan Harris University of Connecticut - Storrs, [email protected]
    University of Connecticut OpenCommons@UConn Doctoral Dissertations University of Connecticut Graduate School 4-20-2018 Cyclic Durability of Thermal Barrier Coatings Subject to CMAS Attack Alan Harris University of Connecticut - Storrs, [email protected] Follow this and additional works at: https://opencommons.uconn.edu/dissertations Recommended Citation Harris, Alan, "Cyclic Durability of Thermal Barrier Coatings Subject to CMAS Attack" (2018). Doctoral Dissertations. 1732. https://opencommons.uconn.edu/dissertations/1732 Cyclic Durability of Thermal Barrier Coatings Subject to CMAS Attack Alan Barkley Harris, PhD University of Connecticut, 2018 Thermal barrier coatings (TBCs) are critical in modern gas turbine engines, increasing operating temperature, efficiency, and component life. Engines have reached temperatures at which ingested debris (CMAS) forms silicate melts that chemically and mechanically attack TBCs, leading to premature failure. New, CMAS-resistant coatings must be validated under conditions that recreate real-world TBC-CMAS interactions. No standardized testing to perform these analyses currently exists. A cyclic thermal gradient rig with incremental CMAS deposition was developed based on modified literature designs. Tests performed using literature-based parameters showed TBC- CMAS interactions and failure morphology deemed not real-world representative by an engine manufacturer. The results were rationalized with the understanding that, in an engine, “cooling air” is relatively hot (~400 °C). Minimizing transient thermal gradients across the TBC coupon resulted in more representative test outcomes. A second generation thermal gradient rig was developed with higher heat flux and sample throughput. This rig incrementally deposits CMAS powder, a feature not found on existing rigs. Heterogeneous CMAS was deposited onto an EBPVD YSZ TBC coupon.
    [Show full text]
  • Thermal Barrier Coating System and Different Processes to Apply Them- a Review
    ISSN(Online) :2319-8753 ISSN (Print) : 2347-6710 International Journal of Innovative Research in Science, Engineering and Technology (An ISO 3297: 2007 Certified Organization) Vol. 4, Issue 9, September 2015 Thermal Barrier Coating System and Different Processes to apply them- A Review Shubham Barnwal1, B.C.Bissa2 Student Scholar, Dept. of Mechanical Engineering, RCOEM, Nagpur, Maharashtra, India1 Assistant Professor, Dept. of Mechanical Engineering, RCOEM, Nagpur, Maharashtra, India2 ABSTRACT: The depletion of fossil fuels and their increased cost has driven the attention towards energy security. The energy security can be moderately achieved by improving the efficiency of energy producing equipments. Thermal Barrier Coatings (TBCs) are refractory metal compounds deposited on substrate to reduce thermal loss and to protect components from high temperature. In this paper, a review about Thermal Barrier Coatings and different types of thermal spray processes involved for applying coatings is presented. (TBCs) are composite overlay of bond coat and ceramic topcoat on a substrate. Thermal sprayed coatings are extremely effective at increasing the component‟s life and value, further TBC decreases machinery down-time, and improve performance in a wide variety of applications. KEYWORDS: Thermal Barrier Coatings (TBCs), Thermal Spray Coating Techniques. I. INTRODUCTION The trend in mechanical engineering has long been depicted by conflicting requirements: on one hand, customers want increasingly compact and lightweight parts while on the other hand, more stringent requirements are being imposed on engineered parts in terms of performance, reliability, and service life. Moreover, customers insist on reducing energy consumption and the use of ecologically safer coolants, lubricants and similar consumables in the smallest possible quantities.
    [Show full text]
  • History of Thermal Barrier Coatings for Gas Turbine Engines Emphasizing NASA’S Role from 1942 to 1990
    NASA/TM—2009-215459 History of Thermal Barrier Coatings for Gas Turbine Engines Emphasizing NASA’s Role From 1942 to 1990 Robert A. Miller Glenn Research Center, Cleveland, Ohio March 2009 NASA STI Program . in Profi le Since its founding, NASA has been dedicated to the papers from scientifi c and technical advancement of aeronautics and space science. The conferences, symposia, seminars, or other NASA Scientifi c and Technical Information (STI) meetings sponsored or cosponsored by NASA. program plays a key part in helping NASA maintain this important role. • SPECIAL PUBLICATION. Scientifi c, technical, or historical information from The NASA STI Program operates under the auspices NASA programs, projects, and missions, often of the Agency Chief Information Offi cer. It collects, concerned with subjects having substantial organizes, provides for archiving, and disseminates public interest. NASA’s STI. The NASA STI program provides access to the NASA Aeronautics and Space Database and • TECHNICAL TRANSLATION. English- its public interface, the NASA Technical Reports language translations of foreign scientifi c and Server, thus providing one of the largest collections technical material pertinent to NASA’s mission. of aeronautical and space science STI in the world. Results are published in both non-NASA channels Specialized services also include creating custom and by NASA in the NASA STI Report Series, which thesauri, building customized databases, organizing includes the following report types: and publishing research results. • TECHNICAL PUBLICATION. Reports of For more information about the NASA STI completed research or a major signifi cant phase program, see the following: of research that present the results of NASA programs and include extensive data or theoretical • Access the NASA STI program home page at analysis.
    [Show full text]
  • Thermal Stress Analysis of Environmental Barrier Coatings Considering Interfacial Roughness
    coatings Article Thermal Stress Analysis of Environmental Barrier Coatings Considering Interfacial Roughness Guangwu Fang 1,* , Jiacheng Ren 1, Jian Shi 2, Xiguang Gao 3 and Yingdong Song 3 1 School of Mechanical Engineering, Anhui University of Technology, Ma’anshan 243002, China; [email protected] 2 Laboratory of Strength, AECC Sichuan Gas Turbine Establishment, Chengdu 610500, China; [email protected] 3 Key Laboratory of Aero-engine Thermal Environment and Structure, Ministry of Industry and Information Technology, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China; [email protected] (X.G.); [email protected] (Y.S.) * Correspondence: [email protected] Received: 10 August 2020; Accepted: 22 September 2020; Published: 30 September 2020 Abstract: A numerical analysis of the effect of roughness interface on the thermal stress in the environmental barrier coatings for ceramic matrix composites was performed. Based on the concept of representative volume elements, a micromechanical finite element model of the coated composites was established. The rough interfaces between the coating layers were described using sine curves. The cooling process after preparation and the typical service conditions for the CMCs component were simulated, respectively. The results show that the rough interface has little effect on the temperature distribution along the depth direction for the studied T/EBC coatings for SiC/SiC composites. The stress concentration occurs at the rough EBC/BC interface, which is prone to cause delamination cracking. Under typical service conditions, the high temperature can eliminate part of the thermal residual stress. Meanwhile, the thermal gradient will cause large thermal stress in the TBC layer and the stress will result in surface cracks.
    [Show full text]
  • Thermal Shock Resistance and Thermal Insulation Capability Of
    materials Article Thermal Shock Resistance and Thermal Insulation Capability of Laser-Glazed Functionally Graded Lanthanum Magnesium Hexaluminate/Yttria-Stabilised Zirconia Thermal Barrier Coating Muhammed Anaz Khan 1, Annakodi Vivek Anand 2, Muthukannan Duraiselvam 3, Koppula Srinivas Rao 4, Ramachandra Arvind Singh 5,* and Subramanian Jayalakshmi 5,* 1 Department of Mechanical Engineering, MLR Institute of Technology, Hyderabad 500043, India; [email protected] 2 Department of Aeronautical Engineering, MLR Institute of Technology, Hyderabad 500043, India; [email protected] 3 Department of Production Engineering, National Institute of Technology, Tiruchirappalli 620015, India; [email protected] 4 Department of Computer Science and Engineering, MLR Institute of Technology, Hyderabad 500043, India; [email protected] 5 Institute of Laser Optoelectronics and Intelligent Manufacturing, College of Mechanical and Electrical Engineering, Wenzhou University, Wenzhou 325035, China * Correspondence: [email protected] (R.A.S.); [email protected] (S.J.) Citation: Anaz Khan, M.; Vivek Anand, A.; Duraiselvam, M.; Srinivas Abstract: In this work, functionally graded lanthanum magnesium hexaluminate (LaMgAl11O19)/yttria- Rao, K.; Arvind Singh, R.; stabilised zirconia (YSZ) thermal barrier coating (FG-TBC), in as-sprayed and laser-glazed conditions, Jayalakshmi, S. Thermal Shock Resistance and Thermal Insulation were investigated for their thermal shock resistance and thermal insulation properties. Results were Capability of Laser-Glazed compared with those of a dual-layered coating of LaMgAl11O19 and YSZ (DC-TBC). Thermal shock ◦ Functionally Graded Lanthanum tests at 1100 C revealed that the as-sprayed FG-TBC had improved thermal stability, i.e., higher Magnesium cycle lifetime than the as-sprayed DC-TBC due to its gradient architecture, which minimised stress Hexaluminate/Yttria-Stabilised concentration across its thickness.
    [Show full text]
  • Durability Modeling Review of Thermal- and Environmental-Barrier-Coated Fiber-Reinforced Ceramic Matrix Composites Part I
    materials Review Durability Modeling Review of Thermal- and Environmental-Barrier-Coated Fiber-Reinforced Ceramic Matrix Composites Part I Ali Abdul-Aziz ID Department of Aerospace Engineering, College of Aeronautics and Engineering, Kent State University, Kent, OH 44242, USA; [email protected] Received: 16 April 2018; Accepted: 13 July 2018; Published: 20 July 2018 Abstract: This paper is a Part I of a literature review documentation describing the currently available and used techniques that are being explored by material scientists and researchers in the field of materials characterizations and testing for both thermal and environmental barrier coatings (TBCs and EBCs, respectively). This review contains relevant information regarding the most common coating applications and their impact on the durability and life of both the coatings and the substrate materials. It also includes a description of the methodologies of coating applications and their pros and cons. A discussion of the applicability, failure modes and modeling approaches that are presently available and utilized by active researchers in the field is also included. Part II will illustrate an in-depth assessment of various aspects of the available and developing life prediction models for both TBC and EBC and the influence of intrinsic and extrinsic factors on their thermal and mechanical stability. Keywords: composites; ceramics; EBC; TBC; failure modes; modeling; coatings; materials testing; processing 1. Introduction Thermal barrier coatings (TBCs) were developed about three decades ago to be used by engine manufacturers for improving engine performance and fuel efficiency to allow for higher operating temperatures while reducing emissions and costs, increasing the life-time of an engine and reducing maintenance costs.
    [Show full text]
  • Thermal Barrier Coatings: Characteristics of Microstructure and Properties, Generation and Directions of Development of Bond
    VOLUME 37 ISSUE 2 of Achievements in Materials December and Manufacturing Engineering 2009 Thermal barrier coatings: characteristics of microstructure and properties, generation and directions of development of bond G. Moskal* Department of Materials Science, Silesian University of Technology, ul. Krasińskiego 8, 40-019 Katowice, Poland * Corresponding author: E-mail address: [email protected] Received 28.08.2009; published in revised form 01.12.2009 Materials ABSTRACT Purpose: The goal of the paper is to present the review of characterisation of microstructure, properties as well as technology of receiving the heat resistance layers used as bond coats in thermal barrier coatings. Design/methodology/approach: General structure characterisation of the final influence of individual TBC`s sublayers was described. Especially the detailed characterisation of bond coats such as MeCrAlY and aluminides diffusion coatings was showed (used for EB-PVD obtained TBC`s). Findings: The influence of modification of chemical composition was described on microstructure and property of bond coats as well. It defines reactive elements such as Hf and the noble metals - Pt influence on increasing of heat resistance of bond coats, and, as a consequence, the growth of durability of coating thermal barriers. Different methods of modification of basic layers, for example the additional aluminizing process of MCrAlY coating was described as well. Practical implications: Additionally, the other types of bond coats were characterised, typically used for energy conversion systems and in case of Diesel engines and especially bond coats for titanium and titanium aluminides alloys. Originality/value: In the last part of the paper, new concepts such as „smart coatings” and diffusion barriers were shown.
    [Show full text]
  • Thermal Shock and Cycling Behavior of Thermal Barrier Coatings (Tbcs) Used in Gas Turbines
    Chapter 10 Thermal Shock and Cycling Behavior of Thermal Barrier Coatings (TBCs) Used in Gas Turbines Abdullah Cahit Karaoglanli, Kazuhiro Ogawa, Ahmet Türk and Ismail Ozdemir Additional information is available at the end of the chapter http://dx.doi.org/10.5772/54412 1. Introduction Gas turbine engines work as a power generating facility and are used in aviation industry to provide thrust by converting combustion products into kinetic energy [1-3]. Basic concerns regarding the improvements in modern gas turbine engines are higher efficiency and per‐ formance. Increase in power and efficiency of gas turbine engines can be achieved through increase in turbine inlet temperatures [1,4]. For this purpose, the materials used should have perfect mechanical strength and corrosion resistance and thus be able to work under aggressive environments and high temperatures [2]. The temperatures that turbine blades are exposed to can be close to the melting point of the superalloys. For this reason, internal cooling by cooling channels and insulation by thermal barrier coatings (TBCs) is used in order to lower the temperature of turbine blades and prevent the failure of superalloy substrates [1-4]. By utilizing TBCs in gas turbines, higher turbine inlet temperatures are allowed and as a result an increase in turbine efficiency is obtained [5]. TBCs are employed in a variety of areas such as power plants, advanced turbo engine combustion chambers, turbine blades, vanes and are often used under high thermal loads [6-11]. Various thermal shock tests are conducted by aerospace and land gas turbine manufacturers in order to develop TBCs and investigate the quality control characteristics.
    [Show full text]
  • The Influence of Thermal Barrier Coating on the Combustion and Exhaust Emission in Turpentine Oil Powered Di Diesel Engine
    VOL. 10, NO 22, DECEMBER, 2015 ISSN 1819-6608 ARPN Journal of Engineering and Applied Sciences ©2006-2015 Asian Research Publishing Network (ARPN). All rights reserved. www.arpnjournals.com THE INFLUENCE OF THERMAL BARRIER COATING ON THE COMBUSTION AND EXHAUST EMISSION IN TURPENTINE OIL POWERED DI DIESEL ENGINE S. Sivaganesan and M. Chandrasekaran Department of Mechanical Engineering, Vels University, Chennai, India E-Mail: [email protected] ABSTRACT Several methods of coatings are used to protect various structural engineering materials from corrosion, wear, and erosion, and to provide lubrication and thermal insulation. Of these, Thermal barrier coatings (TBC) play the most important role in coating of internal combustion engines particular to the combustion chamber. Insulation of the combustion chamber components of low heat rejection (LHR) engines can reduce the heat transfer between the gases in the cylinder and the cylinder wall and thus increase the combustion temperature. This study concentrates on low heat rejection (LHR) engine in which yttria stabilized zirconia (YSZ) are coated to acquire the thermal barrier for the piston crown, cylinder head and valves which will vary depends upon the functional graded material (FGM). A layer of aluminum oxide coating is used to conduct extensive experiments in a single-cylinder Kirloskar TV 1 engine with every piston crown, cylinder head and valves are coated with a layer of ceramic, which consists of zirconia and yttria with varying of thick compositions. This study comprises about diesel blended with turpentine oil which is used in Engine performance measurements. Therefore the characteristics of emissions and combustion were analysed before and after the application of FGM coatings onto the piston crown of cylinder head and valves.
    [Show full text]
  • Thermal-Barrier Coatings for More Efficient Gas-Turbine Engines
    Vol. 37, No. 10, 873–976 Vol. October 2012 Vol. 37 No. 10 www.mrs.org/bulletin MRS BULLETIN Thermal-barrier coatings for more efficient gas-turbine engines Thermal-barrier coatings for more efficient gas-turbine engines efficient Thermal-barrier coatings for more ALSO IN THIS ISSUE Scanning transmission electron microscopy: Seeing the atoms more clearly October 2012 Thermal-barrier coatings for more effi cient gas-turbine engines David R. Clarke , Matthias Oechsner , and Nitin P. Padture , Guest Editors Gas-turbine engines used in transportation, energy, and defense sectors rely on high-temperature thermal-barrier coatings (TBCs) for improved effi ciencies and power. The promise of still higher effi ciencies and other benefi ts is driving TBCs research and development worldwide. An introduction to TBCs—complex, multi-layer evolving systems—is presented, where these fascinating systems touch on several known phenomena in materials science and engineering. Critical elements identifi ed as being important to the development of future TBCs form the basis for the fi ve articles in this issue of MRS Bulletin . These articles are introduced, together with a discussion of the major challenges to improved coating development and the rich opportunities for materials research they provide. Introduction pollution produced by jet engine exhausts.12 Together, these Thermal-barrier coatings (TBCs) are refractory-oxide ceramic developments will require continued innovation in gas turbine coatings applied to the surfaces of metallic parts in the hottest technology and high-temperature engine materials, including part of gas-turbine engines ( Figures 1 and 2 ), enabling mod- TBCs and associated technologies. ern engines to operate at signifi cantly higher gas temperatures Many engineering design factors infl uence the overall than their predecessors (see recent reviews 1–6 ).
    [Show full text]
  • Non-Destructive Evaluation and Maintenance of Thermal Barrier Coatings Martin P
    University of Connecticut OpenCommons@UConn Master's Theses University of Connecticut Graduate School 8-5-2014 Non-Destructive Evaluation and Maintenance of Thermal Barrier Coatings Martin P. Hawron University of Connecticut - Storrs, [email protected] Recommended Citation Hawron, Martin P., "Non-Destructive Evaluation and Maintenance of Thermal Barrier Coatings" (2014). Master's Theses. 648. https://opencommons.uconn.edu/gs_theses/648 This work is brought to you for free and open access by the University of Connecticut Graduate School at OpenCommons@UConn. It has been accepted for inclusion in Master's Theses by an authorized administrator of OpenCommons@UConn. For more information, please contact [email protected]. Non-Destructive Evaluation and Maintenance of Thermal Barrier Coatings Martin Per Hawron B.S. B.S., Southern Arkansas University 2011 A Thesis Submitted in Partial Fulfillment of the Requirements for the Degree of Master of Science at the University of Connecticut 2014 APPROVAL PAGE Master of Science Thesis Non-Destructive Evaluation and Maintenance of Thermal Barrier Coatings Presented by: Martin Per Hawron B.S. Major Advisor:_________________________________________________________ Michael W. Renfro Associate Advisor:______________________________________________________ Eric H. Jordan Associate Advisor:______________________________________________________ Maury Gell University of Connecticut 2014 Acknowledgements Everywhere life has taken me, many have gone out of their way to help me along, and this university has been no exception. I am grateful to Mike Renfro for guiding my academic growth over the past two years, being an ever-approachable laser guru, and for convincing me to come to UConn in the first place. I am much indebted to Eric Jordan for the conversations in which he would communicate more knowledge about TBC’s than you could look up in a week.
    [Show full text]