Simulations On Electrons Scattering In Alloy-plies And Mechanical Characters Of Fullerenes & Fullerene Polymeric Molecules

The thesis has two parts, i.e., Part 1: Simulations on electrons scattering in Al,Ti alloy-plies; Part 2: Mechanical characters of fullerene & fullerene polymeric molecules.Part 1: Simulations on electrons scattering in Al,Ti alloy-plies.Due to the radiant belt, solar wind particles and cosmic rays of galaxy, there are abundant electriferous particles in astrospace, whose energy is from hundreds to millions of eV. The electriferous particles can make radiate damage to alloy-plies of exterior-space aircraft, instruments and astronauts inside the space aircraft. So it is very necessary to simulate middle-energy electrons scattering in the aeronautics & astronautics alloys. In the first part of the thesis, Monte Carlo simulations were performed to investigate the energy and space distributions of electrons scattering in the Ti,Al alloy under the action of middle energy electrons(incident electron energy E0≥500KeV). Further the depth and surface distributions of scattering electrons (SEs) and backscattering electrons (BSEs), energy distributions of BSEs and transmission electrons (TEs), and the energy aggradation in the alloy plies were analyzed. Finally, we get a series of valuable results about electrons scattering in the Ti,Al alloy under the action of middle energy electrons.Part 2: Study on mechanical characters of fullerene & fullerene polymeric.With the improvement of computer software and hardware as well calculation technique, Molecular dynamics(MD),Quantum dynamics(QD) methods have been widely used to study the mechanical & electronic characters of carton fullerenes. Otherwise, the L-J (12-6) potential and the REBO potential are specially used in studying carton systems. first,by the REBO and L-J potential based MD method, the compressive properties of C32, C60, C180 and C60@C180 fullerene molecules under the action of double graphite layers were investigated. According to the obtained results. Second,the REBO potential based MD method was applied to simulate the tension and fracture of the C60 fullerene polymeric layers with no defect, single-edge and center defect, as well as the 7C60 fullerene polymeric chain,respectively. The effects of different defect and tensile velocity on the fracture behaviors and tensile mechanical properties of the C60 fullerene polymeric layers/chain were discussed.