| Abstract Scope |
Polymer derived ceramics(PDCs) are being studied as coating materials to prevent corrosion of nuclear fuel storage made from stainless steel. Polymer coatings can be applied to the stainless surface by solution processes such as spin coating. However, the coatings often undergo volume shrinkage of 50% or more during the polymer conversion to ceramics. As the coating thicker, cracks form and compromise its role as a protective layer. In this study, a SiOCN coating system has been developed using a mixture of polysilazane(PHPS) and polysiloxane(PSO), sealed by a pure SiON layer. When the two precursors are mixed in an appropriate ratio to form a film, a crack-free film greater than 1μm forms. This allows us to increase the coating thickness from ~400nm to more than 1µm. Furthermore, the hardness and Young’s modulus of the film were 10.8GPa and 100GPa, respectively, showing enhanced mechanical properties compared to the single layer SiON film. |