A　thermal　barrier　coating　(TBC)　of　MCrAlY/8YSZ　with　hybrid　microstructure　was　prepared　on　15CrMo　stainless　steel　by　means　of　HVOF　spraying　technique,　namely　the　coating　consists　of　a　hybrid　structured　YSZ　top-coat　made　of　mixture　of　agglomerated　and　fused　and　crushed　YSZ　powder　and　a　bond　coat　of　NiCoCrAlTaY,　while　an　intermediate　layer　of　NiCoCrAlTaY/YSZ　composite　was　inserted　in　between　the　above　two　coats.　The　bonding　strength　and　fracture　toughness　of　the　YSZ　coating　can　be　improved　by　these　two　strategies　to　enhance　the　spallation　resistance　of　the　TBC.　Two　individual　powder　feeders　were　used　to　feed　the　NiCoCrAlY　and　YSZ　powder　independently　into　the　plasma　plume　so　that　the　feeding　rate　and　heating　experience　of　both　powders　can　be　controlled　independently.　SEM　was　used　to　characterize　the　coating　microstructure.　Adhesion　of　the　TBC　coating　was　examined　according　to　ASTM　C633　Standard.　Elastic　modulus,　fracture　toughness　and　thermal　conductivity　of　the　YSZ　layer　were　measured.　Spallation　resistance　of　the　coating　was　assessed　by　water　quenching　test　from　750.　The　results　show　that　the　desired　coating　microstructure　was　achieved　by　HVOF　and　APS,　and　all　the　three　layers　bond　well　each　other　without　any　interfacial　cracks.　The　adhesion　strength　of　the　YSZ　coat　increases　from　25.8　MPa　to　38.6　MPa.　Evident　changes　in　elastic　modulus　and　thermal　conductivity　were　not　detected.　A　great　improvement　of　100%　in　fracture　toughness　of　the　YSZ　coating　was　achieved.　As　a　result　of　all　the　above　measures,　the　occurrence　of　30%　area　spallation　for　the　top　coat　could　be　rose　to　72.1　cycles　during　water　quenching　test,　in　comparison,　only　19.7　for　the　TBC　made　of　the　same　material　with　conventionally　desired　structure.　©　2021,　Editorial　Office　of　Chinese　Journal　of　Materials　Research.　All　right　reserved.