DEVELOPMENT OF COST EFFECTIVE NANOSTRUCTURAL REINFORCEMENTS FOR ADVANCED COMPOSITES
Okonkwo, Anderson O
MetadataShow full item record
The purpose of this work is to develop cost effective structural composites reinforced with complex carbon nanostructures for multiple applications. The main process in this study is mechanical milling which induce the in-situ transformation of carbon in the form of soot into complex nanostructures that behave as effective reinforcements. The soot mainly composed of amorphous particles with a high density of defects having a majority of sp2 bonding. During mechanical milling, this soot transforms in-situ into diamond, graphene and graphitic carbon. Milling media have two fundamental roles: welding and fracturing. A further contribution of milling in metal contamination is in some cases welcomed due to the presence of transition metals (e.g. Fe) with catalytic nature that sponsor further in-situ synthesis of carbon nanoreinforcements during sintering. The in-situ synthesized nanoreinforcements have demonstrated to be effective in improving mechanical properties in composites with various matrices including: ceramics, metallic and polymer (bio, organic and inorganic). Further, in this work is presented a novel sintering method involving induction heating at a high and low temperature. The induction sintering is pressure less. Novel processing technologies were demonstrated through the mechanical and characterization test results. In this study, we innovated a sintering process where induction heating is used and compared to Spark Plasma Sintering (SPS). The results will be supported by mechanical testing and characterization by means of x-ray diffraction, Raman spectroscopy, x-ray photoelectron spectroscopy, scanning and transmission electron microscopy.