【摘要】 采用电镀Pt+气相渗铝的方式,在IC21单晶表面分别制备了985℃/1h、870℃/2h渗铝的NiPtAl涂层,并通过1100℃/80MPa的蠕变中断实验,探究了高温拉应力下界面的组织演化与元素互扩散情况。结果表明,985℃/1h渗铝的样品100h后界面处存在β-NiAl、互扩散区(IDZ)、基体扩散区(SDZ)三层。其中,β-NiAl外层能够阻碍Mo元素从基体扩散进入涂层;SDZ大量析出了有害的TCP相,其厚度随时间的变化基本遵循抛物线规律。870℃/2h渗铝的样品100h后界面不存在SDZ。涂层中仅含有γ’-Ni3Al而无β-NiAl,外层Mo元素含量达到5at.%。更多还原

【Abstract】 In this paper, two NiPtAl coatings by electroplating Pt and following aluminizing(985℃/1 h and 870℃/2 h) were prepared on the surface of the single crystal superalloy IC21. Through creep interruptions at 1100℃/80 MPa, the microstructure evolution and elements interdiffusion of the interface under high temperature tensile load were investigated. After 100 h, the in-terface of the 985℃/1 h aluminized sample contains three layers, respectively β-NiAl, interdiffusion zone(IDZ) and substrate diffusion zone(SDZ). The β-NiAl layer can prevent the diffusion of Mo from the substrate into the coating. Large amounts of harmful TCP phases precipitated in the SDZ, whose thickness basically follows the parabolic law with oxidation time. For the870℃/2 h aluminized sample, no SDZ were observed at the interface after 100 h, the coating contains only γ’-Ni3 Al but no β-NiAl, and the Mo content of the outer layer reached 5 at.%.更多还原