Abstract: A general method of manufacturing high strength ultrafine grained nanostructured carbon and carbide materials that combines densification of nanoparticles with heat treatments or other means of supplying energy to cause fusion of structures that interlink and weld the nanoparticles together. Coatings films, nanopaper, nanopaper laminates, fibers, and extended objects can be manufactured by applying the disclosed methods. The nanomaterials are useful for additive manufacturing of rapid prototyped objects. A variety of nanoparticle starting materials are divulged including but not limited to double walled carbon nanotubes, fluorinated graphene nanosheets, silicon nanowires, and boron nanoplatelets. Articles can be manufactured with spark plasma synthesis, capacitive discharge sintering, hot press apparatus and green bodies can be processed in furnaces.