Methods and compositions for fabricating composite parts including at least one structural material and at least one protective material that are integrally bonded without the use of secondary bonding operations. One or more of the materials forming the layers of the composite parts may be a ceramic composition with or without porosity and one or more of the materials may be a polymer composition. Methods including co-injection processes also are provided for fabricating multi-layered structures in which each layer serves a desired function while still being integrated into the overall structure.