等离子喷涂常规和纳米ZrO_2-7%Y_2O_3热障涂层的热腐蚀性能.pdfVIP

HotWorkingTechnology2014，Vo1．43，No．8

等离子喷涂常规和纳米Zro2-7％Y2O3

热障涂层的热腐蚀性能

王东生‘田宗军。沈理达，黄因慧

(1．南京航空航天大学机电学院，江苏南京210016；2．铜陵学院机械工程学院，安徽铜陵244000)

摘要：采用等离子喷涂技术制备了常规和纳米MCrA1YZ／rO2．7％Y：O，(质量分数)双层系统热障涂层。比较了两种

涂层的微观结构和850℃下75％N~SO+25％NaCl(质量分数)混合熔盐中耐热腐蚀性能，并探讨了涂层的热腐蚀破坏

机理。结果表明，等离子喷涂常规和纳米热障涂层都为典型的层状堆积结构，但与常规涂层相比，纳米团聚体粉末喷涂

过程中熔化充分。其涂层孑L隙率低，组织更致密。两种涂层的热腐蚀破坏都是稳定剂Y20，的消耗而引起的部分四方相

转化为单斜相的马氏体相变．但总体上纳米热障涂层本身的热腐蚀程度要小于常规涂层，其对金属粘结层及基体的保

护也更好。

关键词：等离子喷涂；热障涂层；纳米涂层；热腐蚀性能

中图分类号：TGl74_44文献标识码：A文章编号：1001—3814(2014)08-0156·05

HotCorrosionResistanceofPlasma．sprayedConvenfionaland

Nano-structuredZr02-7％Y2o3ThermalBarrierCoating

WANGDongshengL2，TIANZongjun，SHENLida，HUANGYinhui

(1．CollegeofMechanicalandElectricalEngineering，NanjingUniversityofAeronauticsandAstronautics，Nanjing210016，

China；2．CollegeofMechanicalEngineering，TonglingUniversiyt，Tongling244000，China)

Abstract：Conventionalandnano-structuredMCrA1YZ／rO2-7％Y203(massfraction)double—layersystemthermalbarrier

coatingwerefabricatedbyplasmasprayingprocess．Themicrostructureandhotcorrosionresistanceofhtetwokindsof

coatingin5％Na2SO4+25％NaC1(massfraction)moltensaltat850℃werecompared．Meanwhile，htehotcorrosionfailure

mechanismsofthecoatingwerediscussed．Theresultsshowthathteplasma—sprayedconventionalandnano-strucutredthemral

barriercoatinghavetypicallamellarsatckingcharacteristic．Duetofullymeltedofnano—strucutredagglomeratedpowders

duringplasmaspraying,htenano—strucutredcoatingshowslowerporsiytandhighercompactnesshtnaconventionalone．Owing

othteconsumptionofsatbilizerY2O3，htehotcorrosionfailureofhtecoatingisdominatedbymartensiticrtansformation，

wherepartiallytetragonalZrO2rtansformsintomonoclinicZrO》Thenano-stmctIlredcoaintghasabetterhotcorrosi