为了抑制浇注叶片时合金液与硅基陶瓷型芯的界面反应，从而提高叶片内腔的表面质量，本工作采用原位座滴法研究了多弧离子镀沉积Al₂O₃涂层对硅基陶瓷型芯与镍基单晶高温合金界面反应及润湿性的影响。利用光学轮廓测量仪、SEM和XRD分别对界面反应后合金与陶瓷的表面质量、形貌、元素分布、反应产物进行了分析。结果表明，施加Al₂O₃涂层的硅基陶瓷型芯与合金熔体在高温下接触后，只在合金底部少数区域形成了Al₂O₃及硅化物；而未表面改性的硅基陶瓷型芯与合金熔体接触后，在合金底部形成了连续、致密的Al₂O₃反应层，且基本覆盖合金底部。合金熔体在施加Al₂O₃涂层的硅基陶瓷型芯上的润湿角为89.1°，优于在未表面改性的硅基陶瓷型芯上的100.4°，润湿性显著提高。

Ni-based single-crystal superalloys weaken or even eliminate the influence of weak grain boundaries at high temperatures and contain \ge 60% (volume fraction) of L1₂-type coherent ordering γ'- Ni₃(Al, Ti) precipitation strengthening phase. These superalloys exhibit excellent properties at high temperatures such as, high resistance to oxidation, creep, and fatigue resistance, making them the preferred materials for manufacturing advanced aviation engine turbine blades. The inner cavity structure of engine turbine blades has become complex with the rapid development of the engine manufacturing industry, making investment casting technology as a key technology in blade production. Si-based ceramics are selected as core materials owing to their low thermal expansion coefficient, good dimensional stability, and easy solubility. However, during pouring, active elements such as Hf, Al, and Cr, in the superalloy liquid, undergo thermo-physicochemical and thermomechanical infiltration with the cores when they come in contact with Si-based ceramic cores for extended period at high temperatures. This results in interface reactions and sand formation on the casting surface, thereby reducing the quality of the blade's inner surface and increasing subsequent processes such as eliminating the reaction layer through certain chemical methods. To suppress the interface reaction between the superalloy liquid and Si-based ceramic cores during blade casting and improve the surface quality of the blade inner cavity, the effect of Al₂O₃ coating on the surface of Si-based ceramic cores were investigated using the multi-arc ion plating method. Furthermore, the effect of Al₂O₃ coating on the interface reaction and wettability between Si-based ceramic cores and the superalloy were explored using the in situ droplet method. The surface quality, morphology, element distribution, and reaction products of the interface reaction were analyzed via optical profilometry, SEM, and XRD, respectively. It has been found Al₂O₃ and silicides are generated in few areas at the bottom of the superalloy after high-temperature contact between the Al₂O₃-coated Si-based ceramic cores and superalloy melt. However, a continuous and dense Al₂O₃ reaction layer is formed at the bottom of the superalloy after contact between the unmodified Si-based ceramic cores and superalloy melt. The wetting angles of the superalloy melt on the Al₂O₃-coated and unmodified Si-based ceramic cores are 89.1° and 100.4°, respectively, indicating that the wettability is substantially improved by the Al₂O₃ coating. Results indicate that applying Al₂O₃ coating on Si-based ceramic cores can effectively suppress the interface reaction between Ni-based single-crystal superalloy and Si-based ceramic cores and improve the filling ability of the superalloy liquid during casting.