RESEARCH

1. Theoretical and Experimental Fracture Mechanics and Failure Analysis

Crack layer (CL) theory is a very unique theory of coupled crack and process zone (PZ) based on thermodynamics and mechanics. CL theory addresses the crack propagation problem by the constitutive relations for a crack and accompanying process zone growth as a nonlinear system of equations (driving forces for crack and process zone). CL theory is a generalized theory but it is especially the best theory to explain the discontinuous crack propagation behavior of polymers. Professor Alexander Chudnovsky proposed CL theory, and there are a lot of opportunities to apply this generalized theory to practical crack problems. To apply CL theory to various cases, the characteristics of process zone should be investigated by experiment.

2. Investigation of Mechano-Chemical Degradation of Engineering Materials

Stress corrosion cracking (SCC), one of major mechano-chemical degradation-induced-failures, of polymers is an important issue for portable water transportation as a long term property (mainly due to Chlorine attacks). Due to the complexity and high cost of SCC test in polymer, researches on SCC of pipe are limited to the case studies. Based on the theoretical prediction models for both of SCC initiation and propagation which were proposed by Choi et al., polymer pipes under aggressive environment can be designed in cheaper and more effective ways for various applications.

3. Investigation of Structure-Property-Process Relationship of Engineering Polymers

The unique material properties of polymers and versatility of processing methods are attributed to their molecular structures. Because of the versatility of polymers, many parts and components, which have been made of wood, metal, ceramic or glass are redesigned with polymers. So, there are a lot of opportunities of studying mechanical and physical properties of polymers considering molecular structure and thermo-mechanical properties of polymers. Some major opportunities: Understanding of tear mechanism of thin films (blown films, extruded films, compression molded films), understanding of creep properties (tensile creep, flexural creep, compression creep and so on), investigation of slow crack growth properties and dynamic crack growth properties, investigation of wear and scratch etc.

4. Development and Characterization New Engineering Materials

Due to the continuous demand of engineering materials with improved physical properties, various new materials have been developed. By using proper functional fillers or developing sophisticated fabrication processes, new materials satisfying required physical properties can be developed. In many cases, the characterization method of required properties such materials should be developed or modified together to confirm whether the developed material can be launched into the market based on the fundamental understanding of required physical properties and the developed material.

5.Multiphysics Analysis of Battery

Multiphysics analysis of battery is important to observe safety. To define battery behavior, the integrative perspectives needs. By considering mechanical, electro-chemical and thermal behavior of battery, the safety issue of battery such as internal/external short will be considered. Our lab will conduct mechanical test of battery. Then, Multiphysics analysis of battery will be conducted. Commercial Finite Element Program will be used for describing internal/external short of battery. Also, the module`s Multiphysics analysis will also be considered. Main sponsor of this research theme is Hyundai Motors, etc.