Abstract
The main challenge in the production of metal matrix composites reinforced by carbon nanotubes (CNTs) is the development of a manufacturing process ensuring the dispersion of nanoparticles without damaging them, and the formation of a strong bond with the metallic matrix to achieve an effective load transfer, so that the maximum reinforcement effect of CNTs will be accomplished. This research focuses on the production by powder metallurgy of aluminum and nickel matrix composites reinforced by CNTs, using ultrasonication as the dispersion and mixture process. Microstructural characterization of nanocomposites was performed by optical microscopy (OM), scanning and transmission electron microscopy (SEM and TEM), electron backscattered diffraction (EBSD) and high-resolution transmission electron microscopy (HRTEM). Microstructural characterization revealed that the use of ultrasonication as the dispersion and mixture process in the production of Al/CNT and Ni/CNT nanocomposites promoted the dispersion and embedding of individual CNT in the metallic matrices. CNT clusters at grain boundary junctions were also observed. The strengthening effect of the CNTs is shown by the increase in hardness for all nanocomposites. The highest hardness values were observed for Al/CNT and Ni/CNT nanocomposites, with a 1.00 vol % CNTs.
Highlights
Metal matrix composites demonstrate a range of fascinating properties, especially high mechanical ones, including high strength and stiffness, a desirable coefficient of thermal expansion and good damping properties [1,2]
The main aim of this research is to extend the dispersion/mixture process already used on the Al/carbon nanotubes (CNTs) nanocomposites to nickel matrix nanocomposites
Al/CNT and Ni/CNT nanocomposites were produced by powder metallurgy using ultrasonication as the dispersion/mixture process
Summary
Metal matrix composites demonstrate a range of fascinating properties, especially high mechanical ones, including high strength and stiffness, a desirable coefficient of thermal expansion and good damping properties [1,2]. Several investigations have been conducted into the development of metal matrix composites with different types of nanometric reinforcing materials. CNTs have been used to reinforce several metallic matrices, such as aluminum [6,7], nickel [8,9], copper [10,11], titanium [12] and magnesium [13,14], due to their extraordinary mechanical properties and excellent electrical conductivity [15,16]. The successful development of a production process that promotes a uniform and dense dispersion of CNTs in the matrix, without damaging them, is essential for obtaining the expected strengthening of nanocomposites. An effective load transfer from the metallic matrices to the CNTs is the key for the successful production of these nanocomposites.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
