A nanostructured ablative bulk molding compound: Development and characterization

Glass and silica fiber phenolic composite ablators are effectively used in the production of passively cooled rocket combustion chambers. To improve the performance of these composites as well as to decrease their costs, the use of micron sized silicon dioxide particles has been widely adopted. In this work, the possibility of producing glass phenolic composites with nanosized silica as an alternative to micron-scaled silicon dioxide was investigated. The ablative properties of the produced materials were studied using an oxy-acetylene torch. In depth temperature profiles taken through the thickness of the samples, loss of mass data and an optical analysis of the post-test surfaces were used to evaluate the effects of nanosilica. Furthermore, to investigate the material post-test microstructure, a detailed morphological characterization was carried out using Scanning Electron Microscopy (SEM). In comparison to neat glass/phenolic composites, the introduction of nanosized silica particles embedded in the matrix significantly improved the ablative properties in terms of mass loss and erosion rate.