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We review the studies on the thermophysical properties of undercooled metals and alloys by molecular simulations in recent years. The simulation methods of melting temperature, enthalpy, specific heat, surface tension, diffusion coefficient and viscosity are introduced and the simulated results are summarized. By comparing the experimental results and various theoretical models, the temperature and the composition dependences of the thermophysical properties in undercooled regime are discussed.

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This paper describes the delayed effect on the motion characteristics of the slider in the S&A mechanism resulting from the micro-zigzag slot used in OICW (Objective Individual Combat Weapon) and studies its influence on the ability of filtering transient acceleration signals. Firstly, we established the mathematic model of the slider when the S&A mechanism was loaded by the rectangular pulse acceleration according to the Rigid Dynamic Mechanics Theory and got its analytical solution by using MATLAB. Secondly, to verify the feasibility of this micro-zigzag slot mechanism, we adopted two different kinds of acceleration loading curves, after the non-linear dynamic mechanics simulation on it by using ANSYS/LS-DYNA, displacement and velocity curves of the slider were calculated. Then, to find which structural parameter playing more important role in affecting the characteristics of micro-zigzag slot, we adopted Single-variable Method to study its structural parameter under the same simulation condition. The simulation results we got were almost consistent with the theoretical results. The parametric research of the micro-zigzag slot lays certain a foundation on the research of MEMS system.

A novel latch mechanism of centrifugal system in the MEMS fuze S&A mechanism was mechanically analyzed by FEA. By the analysis, the equation of resistance was determined, the same as the equation about the angular velocity of centrifugal system and the reliability of the slider inserting, which were validated by FEA. Setting different parameters in the analysis and comparing the speed curves of sliders inserting into the latches, one method was determined to reduce the vibrating of speed curve. According to the characteristic of MEMS fabrication technology and design requirement for latch mechanism, one of higher reliability and smaller amplitude oscillation of speed curve was selected to simulate when it was imposed by reverse force.