PDF(Pubmed)
Abstract：
Hydrogen atoms can enter into metallic materials through penetration and diffusion, leading to the degradation of the mechanical properties of the materials, and the application of hydrogen barrier coatings is an effective means to alleviate this problem. Zirconia coatings (ZrO2) have been widely studied as a common hydrogen barrier coating, but zirconia undergoes a crystalline transition with temperature change, which can lead to volumetric changes in the coating and thus cause problems such as cracking and peeling of the coating. In this work, ZrO2 coating was prepared on a Q235 matrix using a sol-gel method, while yttria-stabilized zirconia (YSZ) coatings with different contents of rare earth elements were prepared in order to alleviate a series of problems caused by the crystal form transformation of ZrO2. The coating performances were evaluated by the electrochemical hydrogen penetration test, pencil hardness test, scratch test, and high-temperature oxidation test. The results show that yttrium can improve the stability of the high-temperature phase of ZrO2, alleviating the cracking problem of the coating due to the volume change triggered by the crystalline transition; improve the consistency of the coating; and refine the grain size of the oxide. The performance of YSZ coating was strongly influenced by the yttria doping mass, and the coating with 10 wt% yttria doping had the best hydrogen barrier performance, the best antioxidant performance, and the largest adhesion. Compared with the matrix, the steady-state hydrogen current density of the YSZ coating decreased by 72.3%, the antioxidant performance was improved by 65.8%, and the ZrO2 coating hardness and adhesion levels were B and 4B, respectively, while YSZ coating hardness and adhesion were upgraded to 2H and 5B. With the further increase in yttrium doping mass, the hardness of the coating continued to improve, but the defects of the coating increased, resulting in a decrease in the hydrogen barrier performance, antioxidant performance, and adhesion. In this work, the various performances of ZrO2 coating were significantly improved by doping with the rare earth element, which provides a reference for further development and application of oxide coatings.
摘要：
氢原子可以通过渗透和扩散进入金属材料，导致材料的机械性能下降，而氢阻隔涂料的应用是缓解这一问题的有效手段。氧化锆涂层(ZrO2)作为一种常见的氢阻隔涂层,但是氧化锆会随着温度的变化而经历结晶转变，这可能导致涂层的体积变化，从而导致涂层的破裂和剥离等问题。在这项工作中,采用溶胶-凝胶法在Q235基体上制备ZrO2涂层,同时制备了不同稀土元素含量的氧化钇稳定氧化锆（YSZ）涂层，以缓解ZrO2晶型转变带来的一系列问题。通过电化学氢渗透测试评估涂层性能，铅笔硬度测试，划痕试验,和高温氧化试验。结果表明，钇可以提高ZrO2高温相的稳定性，缓解由结晶转变引发的体积变化引起的涂层开裂问题；提高涂层的一致性；细化氧化物的晶粒尺寸。YSZ涂层的性能受到氧化钇掺杂质量的强烈影响，掺杂10wt％的氧化钇的涂层具有最佳的氢阻隔性能，最佳的抗氧化性能，和最大的附着力。与矩阵相比，YSZ涂层的稳态氢电流密度下降了72.3%，抗氧化性能提高了65.8%，ZrO2涂层的硬度和附着力分别为B和4B，分别,而YSZ涂层硬度和附着力分别提升至2H和5B。随着钇掺杂质量的进一步增加,涂层的硬度继续提高，但是涂层的缺陷增加了，导致氢阻隔性能下降，抗氧化性能，和附着力。在这项工作中,稀土元素的掺杂显著改善了ZrO2涂层的各种性能,为氧化物涂层的进一步开发和应用提供了参考。
