In Situ Generated β‐Yb ₂ Si ₂ O ₇ Containing Coatings for Steel Protection in Extreme Combustion Environments

The rapid permeation and degradation of silazane-based coatings by water vapor limit their application in combustion environments. Hence, this work reports on the reaction oligosilazane Durazane 1800 with an appropriate Yb-complex a molecular approach its as protective thin (1.2 µm) for AISI 304 comparison benchmark 2250 combustion-like Fourier transform infrared- nuclear magnetic resonance-spectroscopy elucidate mechanism chemical structure resulting Yb-modified silazanes, whereas elemental X-ray diffractometry analyses confirm formation crystalline β-Yb2Si2O7 SiO2 after pyrolysis at 1000 °C air. Energy dispersive spectroscopy photoelectron profile show enhanced diffusion Fe, Cr, Mn from substrate into Yb50 coating, which is responsible better adhesion (23.7 MPa), scratch tolerance (38 N), decreased coefficient thermal expansion-mismatch to substrate, resisting 9 cycles between 20 °C. Despite low Yb-silicate content (6.8 wt%), only minor damage caused coating wet oxidation moist flowing air (1000 15 h), spalled-off. This clear indication potential Yb2Si2O7-containing protect metals ceramics extreme