Al_(2)O_(3)/Ni-P-SiC复合涂层组织与性能的研究

Micro-structure and Properties of Al_(2)O_(3)/Ni-P-SiC Composite Coatings

目的 采用化学复合镀技术对微弧氧化进行封孔,进而得到抗烧蚀性能优良的 Al_(2)O_(3)/Ni-P-Si C 复合涂层。方法 通过采用扫描电镜(SEM)、光学金相显微镜(OM)、显微硬度仪(Microhardness Tester)、X 射线衍射仪(XRD)、氧–乙炔烧蚀试验(Oxy-Acetylene Ablation Test)等方法,对复合涂层的表面形貌、截面形貌、厚度、显微硬度、物相和抗烧蚀性能等进行分析。结果 陶瓷层原始表面完全被化学镀层覆盖,所制得的复合涂层厚度均匀,化学镀层与陶瓷层紧密嵌合。镀液中的 SiC 浓度对镀覆的速度、镀层中 SiC 粒子的共沉积量有着较大的影响。当粒子质量浓度为 16~20 g/L 时,颗粒的共沉积量较大。化学复合镀 60 min可以得到厚度 20 μm 左右的 Ni-P-SiC 镀层,SiC 颗粒分布均匀。当镀液中 SiC 质量浓度为 16 g/L 时,镀层具有最高的硬度。对比未处理、仅微弧氧化和Al_(2)O_(3)/Ni-P-SiC 复合涂层试样,Al_(2)O_(3)/Ni-P-SiC 复合涂层试样具有最佳的抗烧蚀性能。结论 Al_(2)O_(3)/Ni-P-SiC 复合涂层均匀、致密,具有良好的抗烧蚀。

The work aims to seal the holes of micro-arc oxidation (MAO) through the chemical composite plating technique to obtain Al_(2)O_(3)/Ni-P-SiC composite coatings with excellent anti-ablation performance. Scanning electron microscope (SEM), optical metallographic microscope (OM), microhardness tester, X-ray diffraction (XRD), microhardness tester and Oxy-acetylene ablation test were adopted to analyze the surface morphology, section morphlogy, thickness,microhardness, phase and anti-ablative performance. The results of this thesis showed that the original surface of the ceramic layer was completely covered by chemical plating. The prepared composite coating was uniform in thickness. The chemical plating was closely embedded with the ceramic layer. The concentration of SiC in the plating bath had a great influence on the plating speed and the co-deposition rate of SiC particles in the plating. When the mass concentration of particles was 16-20 g/L, the co-deposition rate of particles was large. Ni-P-SiC coating with a thickness of about 20 μm could be obtained by composite electroless plating for 60 min, and the SiC particles were evenly distributed. The plating had the maximum harness when the mass concentration of SiC in the plating bath was 16 g/L. Compared with the untreated, micro-arc oxidation and Al2O3/Ni-P-SiC composite coating samples,Al_(2)O_(3)/Ni-P-SiC composite coating had the best ablative resistance. The Al_(2)O_(3)/Ni-P-SiC composite coating is uniform and dense, and has excellent anti-ablation performance.