Dynamic vs. quasi-static shear failure of high strength metallic alloys: Experimental issues

Analysis of ASB assisted failure in a high strength steel under high loading rate

“…9a tends to remain unchanged, while the y-component DU notch y starts growing). This succession of events is the consequence of wave interactions, as suggested in [19]. Displacements are then derived with respect to time to estimate notch tip velocities involved during the impact loading.…”

“…The relative shearing velocity DV x reaches a maximal value of 40 m/s at t = 22 ls. Before this velocity peak, a smaller one is observed at t = 12 ls, which can be interpreted as an oscillation resulting from transient effects in the plate [19]. In the sequel, we are focusing on the predominant shear loading mode operating in the time range 0-50 ls.…”

Void collapse/growth in solid materials under overall shear loading

“…(2009), Geffroy et al (2011, and Wang and Wei (2013). As voiding mostly forms within bands of localised deformation, in the form of void sheets as shown in Morgeneyer et al (2014) or adiabatic shear bands as shown in Odeshi et al (2006) and Longère and Dragon (2015), the geometrical configuration retained in the present paper is a layer of periodic cells subject to simple shearing. While Tvergaard, see Tvergaard (2008Tvergaard ( , 2012, focused on shear-loaded unit cells with an empty, single void, we are here conducting numerical simulations on unit cells with one or several, empty or particle-containing voids submitted to overall shear loading.…”

“…However, one can observe the ultimate failure of high strength structural materials under shear-pressure loading (involving consequently negative stress triaxiality) as a consequence of void accumulation and growth within zones of intense shearing (adiabatic shear bands in case of high strain rate loading), see e.g. Longère and Dragon (2015) and Fig.1. Material failure may thus ultimately result from void growth, even under overall, zero or low negative stress triaxiality.…”

“…Evidence of strain localisation within an adiabatic shear band (ASB) and further void growth induced damage in the ASB wake. AfterLongère and Dragon (2015) …”