Oxide-Addition Design and Ni–P Post-Plating of Mo–Mn Metallized Al2O3 Ceramics for RSOC Integration

Ceramic metallization provides an effective insulation strategy for reversible solid oxide cell (RSOC) pipeline connections that are prone to side short-circuiting. In this work, 95 wt.% Al 2 O 3 ceramics were metallized by the activated Mo–Mn method, and 15 metallization formulations with different Mo, MnO, Al 2 O 3 , and SiO 2 contents were designed to optimize the microstructure, phase composition, and bonding strength of the metallized layer. The results show that, after sintering at 1400°C for 1 h, the optimal formulation consists of 70 wt.% Mo, 9 wt.% MnO, 6.3 wt.% Al 2 O 3 , and 14.7 wt.% SiO 2 . Under this condition, the Mo skeleton is continuous, the activator melt forms a glassy phase, and a reliable transition layer is developed at the ceramic/metallization interface, yielding a shear strength of 146.3 MPa. Electroless Ni–P post-plating on the optimized metallized surface produces a dense and continuous coating with typical nodular morphology and an average thickness of about 15–17 µm. The plated layer exhibits a relatively uniform hardness of 382.84 HV and maintains good structural integrity after 300 thermal-shock cycles, demonstrating promising potential for RSOC-related ceramic-to-metal insulating connection components.