Flame-retardant mechanism for platinum coating of nickel-based superalloy

This study presents a novel approach for enhancing combustion resistance of a nickel-based superalloy by the application of platinum coating. The combustion behaviors of Pt-coated samples were studied using the promoted-ignition combustion standard test at 7 -25 MPa ( >= 99.5 % oxygen). In contrast to uncoated samples, the Pt-coated samples exhibit notable improvements in resistance to burning, as demonstrated by reduced combustion length and rate. The underlying mechanism can be ascribed to two factors. One notable effect of the Pt coating is the influence on diffusion and distribution of combustion elements. In particular, it impedes the oxidation and combustion of Al with the highest combustion heat. The second one is the comparatively lower heat released by the Pt-coated samples throughout the combustion process, as well as the substantial capacity to reduce the temperature at which combustion ceases. The aforementioned discoveries offer new perspectives on enhancing the compatibility of metal materials with oxygen.