A process for producing ceramic, or ceramic composite, components having microfeatures by creating a chemical reaction in a castable slurry to bond nano-sized or submicron-sized ceramic powders. The bonding process that gives coherency and strength to the material creates a reaction product or gel-phase resulting from a chemical reaction between the ceramic powder and a reagent, such as an acid, alkali, or inorganic salt solution, that binds the ceramic powder. This gel-phase can be de-hydrated, cured, or crystallized by a higher-temperature firing step, but at a temperature lower than the temperature range at which sintering starts to occur in the ceramic (typically lower than 1,000°C.)