Investigation of the mechanical properties of the Ni–P–CNTs coated copper composite materials: Experiments and modeling

Recent studies on the mechanical properties of nickel–phosphorous–carbon nanotubes (Ni–P–CNTs) coated copper composite materials have shown surprising results. Their Young’s modulus and tensile strength cannot reach the theoretical values, even falling below those of copper, and the Young’s modulus decreases with the increment of CNT concentrations. Materials used in those studies were prepared through electroless composite plating process, with the Ni–P–CNTs composite electrolessly deposited on the copper substrate. In the present study, however, it is shown that the Young’s modulus and the tensile strength do increase significantly with the increment of the CNT concentrations without activating the CNTs. A composite method of Voigt model and a random distributed discontinuous fiber model is applied to obtain the equivalent Young’s modulus of the composite, which agrees very well with the experimental data.