[SY-E7] Metal-coated carbon nanotube reinforced aluminum composites
Carbon nanotubes (CNT) possess excellent mechanical properties in terms of axial elastic stiffness and rupture strength. It is therefore an obvious question whether these properties can be harnessed for structural applications by using such nanoparticles as fillers in low-melting lightweight metals such as Al or Mg nanocomposite. To this end, homogeneous dispersion of CNT in the metal matrix and strong interfacial bonding are essential factors since agglomerated nanoparticles with weak bonding into the surrounding metal matrix might act as flaws which actually deteriorate, rather than improve, the mechanical properties of composites. However, good dispersion and strong interfacial bonding are hindered by the low affinity of CNT to Al or Mg. To overcome this problem, interface engineering approaches such as coating CNT with an appropriate metal such as Nitweight , or by decorating them with metal nanoparticiles, may offer a promising approach towards the efficient fabrication of lightweight metal-CNT nanocomposites.
In this work we study how metal coated or metal decorated carbon nanotubes affect the mechanical properties of aluminium/CNT composites. In particular we look at the pullout behaviour of pristine as well as Ni coated or Ni decorated CNT from an aluminium matrix. Our result shows that Ni coating produces an extended interface (“intephase”) where a significant amount of energy is dissipated during CNT pull-out, leading to a high pull-out force. We then investigate the interaction of embedded CNT with and without coating/decoration with cracks and with dislocations during simulated tensile tests. We discuss the results in view of promising approaches for engineering CNT-metal interfaces such as to achieve high strength and high toughness of the metal-CNT composites.
In this work we study how metal coated or metal decorated carbon nanotubes affect the mechanical properties of aluminium/CNT composites. In particular we look at the pullout behaviour of pristine as well as Ni coated or Ni decorated CNT from an aluminium matrix. Our result shows that Ni coating produces an extended interface (“intephase”) where a significant amount of energy is dissipated during CNT pull-out, leading to a high pull-out force. We then investigate the interaction of embedded CNT with and without coating/decoration with cracks and with dislocations during simulated tensile tests. We discuss the results in view of promising approaches for engineering CNT-metal interfaces such as to achieve high strength and high toughness of the metal-CNT composites.