【摘要】 大气等离子喷涂ZrO2-7%Y2O3(7YSZ,Y2O3为质量分数)热障涂层广泛用于航空发动机热端部件以提高金属基体的抗腐蚀、耐高温、抗冲蚀等性能。采用超音速火焰喷涂(HVOF)以NiCoCrAlYTa粉为原料在高温合金K4169基体上制备了粘结层,通过大气等离子喷涂(APS)分别以团聚、空心7YSZ粉为原料在粘结层上制备了陶瓷面层。使用扫描电镜(SEM)和工业电子计算机X射线断层扫描技术(ICT)对团聚、空心粉热障涂层的微观结构进行观察分析,然后再对以上2种热障涂层的抗氧化、热震、结合、隔热等热物性能进行对比分析。研究结果表明:空心粉热障涂层陶瓷层中存在大量的微孔和裂纹;热障涂层陶瓷层中不同孔隙率对粘结层高温抗氧化性能没有明显的影响,但它有助于提高热障涂层的热震性能和隔热性能;此外,高的涂层孔隙率会导致空心粉热障涂层的结合强度低于团聚粉热障涂层。更多还原

【Abstract】 Atmospheric plasma sprayed Zr O2-7wt%Y2O3(7YSZ),functioned as thermal barrier coatings(TBCs),are widely used in industrial gas turbine engines so as to protect the superalloy blades from failure.Using Ni Co Cr Al YTa powder as starting material a bond coating was prepared on K4169 superalloy substrate by high velocity oxygen flame(HVOF).Ceramic top coatings were prepared on the above mentioned bond coating by atmospheric plasma spray(APS) using agglomerated and sintered(referred to as "AS") powder and hollow spherical(referred to as "HS") powder,separately as starting materials.The microstructures of above two sorts of thermal barrier coatings(TBCs) were characterized by scanning electron microscope(SEM) and industrial computed tomography(ICT).Thermal oxidation resistance,thermal shock and adhesion strength,insulation property of both TBCs were compared.The results indicate that the TBCs made of HS have more pores and microcracks than the TBCs made of AS.Different porosities of TBCs have no obvious effect on thermal oxidation property.The TBCs made of HS have better thermal shock resistance and insulation property than the TBCs made of AS,but the formers adhesion strength is lower than the later’s.The former is 35 MPa,while the later is 54 MPa.更多还原