Damage based model to study the effect of notch introduction technique on the J-integral value of PolyOxyMethylene

Experimental data on a CT specimen made of PolyOxyMethylene were enriched by in situ laminographic observations in 3D. The observed micro-mechanisms of crack initiation and growth have been simulated by using a damage based model. A critical value of J-integral was determined. The same model was utilized to simulate an initially heterogeneous porosity in the CT specimen to mimic the state of the material after a cutting process. A notch tip touching tool led to a less compliant specimen and a higher value of critical Jcr whereas non touching conditions, induced a damaged layer around the notch tip leading to a decrease in Jcr.