پديد آورنده :
لقمان استركي، محمدرضا
عنوان :
توليد و شناسايي پودر نانو ساختار زير كونياي پايدار شده با اسكانديا- ايتريا براي ايجاد پوشش هاي سد حرارتي
محل تحصيل :
اصفهان: دانشگاه صنعتي اصفهان، دانشكده مواد
صفحه شمار :
[نه]،120ص: مصور،جدول،نمودار
يادداشت :
ص.ع.به فارسي و انگليسي
استاد راهنما :
حسين ادريس، رضا شجاع رضوي
توصيفگر ها :
پوشش سد حرارتي نانو ساختار , روش پچيني , پاشش پلاسمايي , پاشش خشك , نانو گرانول , سل-ژل
تاريخ نمايه سازي :
29/2/93
استاد داور :
فخرالدين اشرفي زاده، محمدحسين حبيبي، حسن حدادزاده
كد ايرانداك :
ID620 دكتري
چكيده انگليسي :
Synthesis and characterization of nanostructured scandia yttria stabilized zirconia powder for thermal barrier coatings Mohammad Reza Loghman Estarki mr loghman@ma iut ac ir Date of Submission March 12 2014 Department of Materials Engineering Isfahan University of Technology Isfahan 84156 83111 Iran1st supervisor Hossein Edris Professor h edris@cc iut ac ir2nd supervisor Reza Shoja Razavi Associate professor r shoja@yahoo comDepartment Graduate Program Coordinator Dr Keyvan Raeissi Department of Materials Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Department of Material Engineering Malek Ashtar University of Technology Isfahan Shahin shahr IranAbstractNanostructured scandia yttria doped zirconia 5SYSZ thermal barrier coatings TBCs wereproduced by plasma spraying method The microstructure adhesion strength hightemperature phase stability thermal insulation capacity thermal diffusitivity hot corrosionand thermal shock resistance were evaluated and compared with conventional YSZcoatings The results indicated that the hot corrosion resistance and thermal cycling lifetime ofnanostructured SYSZ TBCs was longer than the conventional YSZ TBCs due to the moreacidic nature of Sc2O3 than Y2O3 and lower thermal mismatch stress between the ceramiclayer and the metallic layer at high temperature respectively Moreover the nanostructured5SYSZ coating had higher thermal stability and thermal insulation capacity than 7YSZ TBC Keywords Thermal barrier coatings Atmospheric plasma spraying Nanogranule Hotcorrosion Sol gel 1 IntroductionThermally sprayed thermal barrier coatings TBCs have been used successfully in gasturbine components to protect the metal parts from hot burner gases This had led to furtherincrease in operating temperature and some decrease in the amount of cooling air Nowadays state of the art 7wt yttria stabilized zirconia 7YSZ is widely used as standard TBCtopcoat material However the most critical issue for YSZ is the limited operationtemperature 1 523 K for long term applications At higher temperature phasetransformations and porous coating sintering result in the formation of cracks in the coatingand higher thermal conductivity and accelerate the spallation failure of TBCs Therefore investigation of novel TBC materials with ultra high temperature capability low thermalconductivity and long term life time is a key problem for the next generation turbine engines Some ceramic materials such as La2O3 Y2O3 ZrO2 Gd2O3 Y2O3 ZrO2 La2Zr2O7 La2Ce2O7 LaMgAl11O19 and other kinds of rare earth doped zirconia have been investigated as potentialTBC materials In recent years nanostructured zirconia based TBCs deposited byatmospheric plasma spraying have been the focus of attention It was reported thatnanostructured thermal barrier coatings had high bonding strength low thermal conductivityand prolonged thermal cycling lifetime 1 Accordingly nanostructured TBCs are expectedto provide better performance than the conventional TBCs Recently codoping YSZ with Al2O3 Sc2O3 Y2O3 Bi2O3 Sm2O3 Yb2O3 CeO2 etc hasattracted researchers to improve thermal and electrical properties of this ceramic The YSZ
استاد راهنما :
حسين ادريس، رضا شجاع رضوي
استاد داور :
فخرالدين اشرفي زاده، محمدحسين حبيبي، حسن حدادزاده
