Simulation du comportement de la silice sous indentation Vickers par la méthode des elements discrets: densification et mécanismes de fissuration

Abstract

The indentation response of glasses can be classified into three classes : normal, anomalous and intermediate depending on the deformation mechanism and the cracking response. Silica glass, as a typical anomalous glass, deforms primarily by densification and has a strong tendency to form cone cracks that can accompany median, radial and lateral cracks when indented with a Vickers tip. This is due to its propensity to deform elastically by resisting plastic flow. Several investigations of this anomalous behavior can be found in the literature. The present paper serves to corroborate these results numerically using the discrete element method. A new pressure-densification model involving the discrete element method (DEM) is developed that allows for a quantitative estimate of the densification under very high pressure. This model is then used to simulate the Vickers indentation response of silica glass under various indentation forces. The numerical results obtained compare favorably with past experimental results.