The world’s experience in using hafnium in two important parts of high-temperature thermal barrier coatings, such as the top thermal barrier layer and bond coat layer, was analyzed. In the top thermal barrier layer, hafnium is present as HfO₂ completely or partially stabilized by yttria (or other rare-earth oxides). Another approach is to use hafnium dioxide as an addition to conventional coatings based on ZrO₂ stabilized completely or partially. Electron-beam physical vapor deposition (EB-PVD) and air plasma spray process (APS) are most common techniques for applying thermal barrier coatings containing hafnium dioxide. Magnetron sputtering turned out to be successful as well. Compared to the 8YSZ coating, the 7.5YSH coating showed reduced Young’s modulus, 30% lower thermal conductivity (decreased to 0.5–1.1 W/(m · K)) at high temperatures for HfO₂ stabilized with 27 wt.% Y₂O₃, and higher sintering resistance and heat resistance. Doping of ZrO₂ and HfO₂ by several stabilizers proved to be promising: specifically, doping by a mixture of one trivalent ion larger than Y³⁺ and another trivalent ion smaller than Y³⁺, preserving the metastable structure of the t′ phase. The importance of phase diagrams for a correct choice of the top coat composition and doping elements for the bond coat is shown. Doping the bond coat with a small amount (up to 1 wt.%) of hafnium improved its cyclic oxidation resistance and increased the adhesion of the thermally grown oxide layer to the bond coat and strength of the latter.

分析了世界在高温热障涂层的两个重要部分，如顶部热障层和粘合涂层中使用铪的经验。在顶部热障层中，铪以被氧化钇（或其他稀土氧化物）完全或部分稳定的HfO ₂形式存在。另一种方法是使用二氧化铪作为基于 ZrO _{2 的}常规涂层的添加剂完全或部分稳定。电子束物理气相沉积 (EB-PVD) 和空气等离子喷涂工艺 (APS) 是应用含有二氧化铪的热障涂层的最常用技术。磁控溅射也证明是成功的。与 8YSZ 涂层相比，7.5YSH 涂层在高温下对于用 27 wt.% Y ₂ O ₃稳定的HfO ₂表现出降低的杨氏模量、低 30% 的热导率（降低至 0.5–1.1 W / (m·K)），以及更高的耐烧结性和耐热性。通过几种稳定剂掺杂 ZrO ₂和 HfO ₂被证明是有前途的：具体来说，通过一种比 Y ³⁺大的三价离子的混合物掺杂和另一个小于 Y ^{3+ 的}三价离子，保留了 t ' 相的亚稳态结构。显示了相图对于正确选择粘合涂层的面漆组合物和掺杂元素的重要性。用少量（最多 1 重量%）铪掺杂粘合涂层提高了其抗循环氧化性，并增加了热生长的氧化物层对粘合涂层的附着力和后者的强度。