熱障涂層高溫氧化和熱沖擊失效研究.pdf

1、V8《880學校代碼10699分類號TB323密級學號026160554西北工業(yè)大學NORTHWESTERNPOLYTECHNICALUNIVERSITY碩士學位論文熱障涂層高溫氧化和熱沖擊失效研究作者：張勇導師：刊曜會學科：舊體力學中困西安2005年8月ABSTRACTAsOReofadvancedhightemperatureprotectivecoatingtechniquesforworkingoRthehotsectionco

2、mponents，thermalbarriercoatings(TBCs)cannotonlyincreaseworkingtemperature，butalsoimproveservicelifeofthecomponentsInthefutureTBCshavepromisingattractiveapplicationsandresearchesInenergy、ships、aviationandspacelightSoitisv

3、eryimportanttostudythefailuremechanismofthethermalbarriercoatingsandthedevelopmentofstructureInthispaper，thethermalstressinthedoublelayerthermalbarriercoatingspecimensandthefailuremechanismofthecoatingwereanalyzedFirstth

4、epJasnlasprayingmethodwasusedtomanufactureasetofdoublelayerthermalbarrierspecimensThen，theoxidationtestathightemperatureandthermalshockexperimentwereperformedwiththesespecimensonthehightemperaturetestmachineThesampleswer

5、eobservedandtheexperimentalresultswereanalyzedItwasfoundthataxialcrackappearedonthecylindricalsample’sTBCsunderthethermalshock，thiscrackwascausedbythecircumferentialstress；Spallingeventsinthedisksamplewasdetected，thiswas

6、causedbythehighstressgradientinbondcoatSecond，MARCasafiniteelementmethod(FEM)’sanalyzedsoftareusedtoestablishamodalforsomeanalyticsimulation，andtoinvestigatetemperatureandstressdistributionintheTBCsunderthethermalshockIt

7、wasanalyzedindetailwhenthemiddlecoatingsfailed，suchasbiaxialstressandshearingstress，discussedtheirroleinthecourseofthefailuremechanismComparedthestressdistributionunderexternalappliedloadwiththestressdistributionoffreelo

8、ad，wecanfindtheeffectofthefailureontheTBCsbytensionstressandcompressionstressAtthesametimethestressdistributionwasalsocomparedwiththedifferentcoatingsthicknessFinally，weuseanewnon—destructivetestingtoolPhotoluminescencet