锆合金表面磁控溅射制备SiC/Cr复合涂层的研究

Synthesis and Property Characterization of Magnetron Sputtered SiC/Cr Coatings on Zr-Based Alloy

通过直流磁控溅射方法在锆合金基体表面沉积Cr涂层,再在Cr层上射频磁控溅射制备Si C涂层,探索了基体预处理方式、射频溅射功率对涂层结合力、厚度和表面质量的影响。采用扫描电镜及能谱仪,红外光谱和X射线衍射仪对Si C/Cr复合涂层样品进行成分分析,结果表明所制备的涂层Cr层为晶态,Si C层为非晶态。高温水蒸汽氧化实验表明Cr作为锆合金与Si C涂层之间的过渡层,不仅能够缓解Si C层和锆合金基体的热膨胀系数差异,提高涂层结合力,还能增加涂层的延展性,减少基体在高温水蒸气环境下的氧化和断裂。

The SiC/Cr coatings were consecutively deposited by DC and RF magnetron sputtering on Zr-based alloy substrate. The influence of the Cr transition layer and RF sputtering power on the interracial adhesion, film thickness and surface properties was investigated with X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy and energy dispersive spectroscopy. The results show that the cubic crystalline Cr-transition layer strongly improved the surface and interfacial properties of the amorphous SiC coatings. To be specific, the Cr-layer increased the interfacial adhesion and ductility of the SiC coating and decreased the thermal-expansion coefficient difference between the SiC layer and substrate in high temperature steam oxidation. The SiC/Cr coatings significantly enhanced the surface oxidation resistance and fracture resistance in an environment of high temperature steam.