BEHAVIOR OF PLATINUM REINFORCED WITH CARBON NANOTUBES UNDER COMPRESSIVE LOAD

10.25712/ASTU.1811-1416.2022.03.002

Abstract

In this work, using atomistic modeling by the method of molecular dynamics, the authors reveal the elastic properties of a composite based on Pt and CNTs in the case of external action in the crystal orientation <001> (uniaxial observation) at four different strain rates. The simulation results are compared with a Pt single crystal. A cube containing over 5,000 atoms has been discovered. To form a Pt-CNT nanocomposite, a single-layer carbon nanotube of the “zigzag” type with chiral indices (8.0) containing 320 atoms was placed in a single-crystal metal matrix. Thus, the volume fraction of CNTs in the Pt-CNT composite is 5.8 %. The interaction potential of all particles of the nanocomposite was represented by a multipart potential obtained by a modified atom immersion method. Mechanical stresses are calculated from the virial stress. The results of molecular dynamics simulation in this work using the LAMMPS software package. In the work, an increased Young pressure and a decrease in the compressive density of the Pt-CNT nanocomposite compared to platinum were found. It is assumed that the Young's modulus increases due to the high rigidity of CNTs; the decrease in rigidity is probably associated with the shortening of atomic bonds at the interface between Pt and CNT.