Evaluation of Carbon/Epoxy Delamination Fracture Toughness

Effect of Elevated Temperature and Loading Rate on Delamination Fracture Toughness

The effects of temperature and loading rate on delamination growth were studied. The delamination fracture toughness of IM7/K3B was measured at 149°C, 177°C, and 204°C. At each temperature the tests were performed with a variety of loading rates so that the delamination initiated over the range of time from 0.5 sec to 24 hrs. The double cantilever beam (DCB) test was used to measure fracture to...

Fracture toughness of graphene.

Perfect graphene is believed to be the strongest material. However, the useful strength of large-area graphene with engineering relevance is usually determined by its fracture toughness, rather than the intrinsic strength that governs a uniform breaking of atomic bonds in perfect graphene. To date, the fracture toughness of graphene has not been measured. Here we report an in situ tensile testi...

Fracture Toughness of Metal Castings

MULTI FRACTURE/DELAMINATION ANALYSIS OF COMPOSITES SUBJECTED TO IMPACT LOADINGS

A combined finite/ discrete element method is presented for modelling of composite specimens subjected to dynamic/impact loadings. The main task is set on developing an algorithm for simulation of potential bonding and debonding/delamination phenomena during impact or general dynamic loading conditions. In addition, full fracture analysis can also be performed. The proposed approach adopts a ge...

Mode Dependent Toughness and the Delamination of Compressed Thin Films

We consider the buckle-driven delamination of compressed thin lms. For a wide class of patterns of delamination, it is shown that the loading on the delamination front progressively goes from mode I to mode II during growth of the blister. As a result, the mode dependence of the lm/substrate interface excludes widespread delamination. This explains the observations of blisters of nite extent, w...