| 초록 |
Crack layer (CL) theory is an excellent method to explain the slow crack growth and stability of engineering materials by bridging material science studies (the hierarchy of microdefects, their nucleation, interaction and development) and continuum mechanics studies. Especially, the flexibility of CL theory enables the analysis of slow crack growth behavior of polymeric materials for which the conventional fracture mechanics may not applicable. Process zone (PZ) that surrounds and precedes crack is a common feature of fracture in engineering polymers. Depending on material, specimen geometry, temperature, and loading conditions various types of microdefects such as crazes, shearbands, microcracks, etc, constitute PZ. Some significant examples of the slow crack growth behavior of polymeric materials will be discussed, and the methodology of modeling the slow crack growth behavior of polyethylene (PE) will be provided with some experimental observations. |
