Degradation of Polycarbonate Properties Under Thermal Aging

Journal of Failure Analysis and Prevention - The aim of this paper is to characterize the thermal aging effect near the glass transition temperature of polycarbonate (PC) at different hold time....     

Ductile Fracture Study of Stainless Steel AISI 304L Thin Sheets Using the EWF Method and Cohesive Zone Modeling

The purpose of this study is to model the ductile fracture phenomenon using experimental and numerical methods. The stainless steel AISI 304L thin sheets are studied including two thicknesses (0.8 and 1.5 mm). A mechanical characterization is firstly done in order to obtain the main mechanical properties useful for the numerical modeling. In order to determine the essential work of fracture (EWF), DENT specimens are used involving the two thicknesses. The results obtained in terms of EWF for the two thicknesses are close; we find that the essential work of fracture can be considered as an intrinsic criterion for thin sheets. A cohesive zone modeling (CZM) is used in the present study; the model is represented by a traction–separation law (TS). The cohesive elements are implemented in the finite element model, and the material parameters of the model are determined by the mechanical and fracture characterizations. A satisfactory reproduction of the experimental tests is obtained. A good correlation is also obtained between the essential work of fracture determined experimentally and the work of separation used as cohesive zone model parameter.