Fabrication of Carbon nanotubes reinforced Aluminum nanocomposite with extra adhesion of nanotubes to the matrix

Carbon nanotubes reinforced Aluminum nanocomposites were prepared by ball milling route. CNTs were separately mixed with mechanically activated graphite to encourage carbide formation. Specimens were analyzed by Xray diffractometery and Raman spectroscopy. Crystallite size and dislocation density were calculated by the modified Warren-Averbach. Carbide phase formation was investigated from Raman spectra and it was believed that a band in 950cm-1 is corresponded to Al4C3. In order to evaluate semi-quantitatively of carbide phase, intensity ratio of 950cm-1band versus G band of CNTs were compared. Samples with activated graphite revealed considerable amount of carbide in comparison with samples which were prepared with as-received CNTs. Vickers micro-hardness of the samples was measured. The strengthening contribution of crystallite size, dislocation density and particle dispersion were modeled to evaluate interfacial bonding between CNTs and the matrix. In specimens, included activated graphite, hardening was due to both work hardening and second phase strengthening while for specimens, excluded activated graphite, only hardening due to work hardening was observed. It was deducted addition of activated graphite will lead toimprovement of interface bonding by initiating carbide phase formation at the interface which consequently increase wettability of CNTs by Aluminum

کلیدواژه ها:

Carbon nanotubes ، Aluminum ، Interface bonding ، Amorphized graphite ، Carbide ، Strengthening contribution