Research

• Development of nano-scale wiredrawing: Molecular Dynamics Analysis of defect behavior in iron and steel wire
• Atomistic Study on the Performance of Electrolytes in Lithium Ion Batteries(LIB): Evaluation of Li+ diffusion, viscosity and ionic conductivity
• Plastic Deformability and Strength Evaluation of Silicon Based Hard Brittle Material (SiC)
• Mechanical Transmission in Hierarchical Structure of Biological Fibrillar Materials (Collagen / Cellulose Nano-sized Fibers): Twisting Force and Its Energy Transmission from Micro to Macro
• Multi-scale Modeling and Analysis of Solid Materials: Collaboration between Molecular Dynamics and Macroscopic Particle Method (Peridynamics Theory)
• Nano-scale Tribology and Plastic Deformation: The Effect of Nano-sized texturing on Friction
• Computer Simulation Methodology for Dynamic behavior of Solid Materials
• Universality of Structures based on Mechanical Function: Development from Molecular Structures to the Concept of Tensegrity

Plastic Deformability and Strength Evaluation of Silicon Based Hard Brittle Material (SiC)

Due to the rapid progress of modern science and technology, problems about depletion of energy are concerned. To resolve these problems, there is an increasing need for energy conservation to obtain great economic and social effects with less energy. In promoting energy conservation, power electronics is trying to obtain an important role. Power electronics is a technology that freely controls voltage, current, frequency, power conversion using a power semiconductor and is used in a wide range of industrial equipment and automobiles. The performance limit of power electronics is said to be determined by the performance of semiconductors. Although much research has been conducted on silicon (Si), the mainstream of power semiconductors, it is said that no further performance can be expected. Therefore, great expectation is given to silicon carbide (SiC) having better physical properties than Si.

SiC is a compound semiconductor composed of Si and carbon (C). SiC is based on the bond Si - C and has different crystal structures (it shows polytype). In the polytype of SiC, the bond and coordination of Si and C do not change, but the probability of occurrence of stacking structure is different depending on the temperature. Among them, there are 3C-SiC, 4H-SiC, and 6H-SiC which are high in probability of occurrence and those are attracting stronger attention as materials for power semiconductors. In particular, we analyze lattice defects for nucleation and development process using molecular dynamics (MD) model of nanoindentation. Here, we are using 3C - SiC model which is relatively easy to conduct atomic simulation.