Issue 57

R. Andreotti et alii, Frattura ed Integrità Strutturale, 57 (2021) 223-245; DOI: 10.3221/IGF-ESIS.57.17

85-degree impact Similarly, the simulation results of the 85-degree impact show an equivalent plastic strain show two peaks of plastic deformation at around 2 millimeters from the epicenter. The calculated equivalent plastic strain field (Fig. 30 and Fig. 31 ) compared to the plastic strain values extrapolated from the experimental micro-hardness profile shows good adherence of the results with an overestimation of the peaks and a slight underestimation of the plastic strain field in the peripherical area. The residual displacement of the plate (Fig. 29) is estimated as 3.5 millimeters, about 13% underestimated with respect to the average value of the displacements measured on the two experimental replicates (Fig. 10).

Figure 28: Dynamic interaction between bullet and plate. From left to right four frames showing the progressive deformation of the impactor and target from initial contact time at 0.005 milliseconds to the stabilization of the plate at 0.2 milliseconds (time scale in seconds).

Figure 29: Field of residual resultant displacement of the plate at the end of the 85-degree impact.

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