Issue 48

O. A. Mocian et alii, Frattura ed Integrità Strutturale, 48 (2019) 230-241; DOI: 10.3221/IGF-ESIS.48.24 233 sandwich panel with composite facesheets type A and polyurethane foam core impacted at 3 m/s. Figure 1 : INSTRON Ceast 9340 drop tower impact system. Impact velocity [m/s] Impact energy [J] Drop height [mm] 3 59.17 460 3.5 80.54 625 4 105.2 815 Table 1 : Impact characteristics of the drop weight tests: impact velocity, impact energy and drop height. R ESULTS AND DISCUSSIONS uring an impact test, the variation of the impact force in time is recorded by the drop tower impact system. Using these data, the software calculates other variations such as impact energy in time and impact force as a function of impactor displacement. It also determines some impact parameters such as peak force, corresponding to the maximum value on the force-time curve, and absorbed energy, calculated as the area under the force-displacement curve. The average values of mass, maximum impact force and absorbed energy of the impacted sandwich panels are listed in Tab. 2. Sandwich panel Mass [g] F max [N] E abs [J] Sandwich panel Mass [g] F max [N] E abs [J] PUR PS PUR PS PUR PS PUR PS PUR PS PUR PS SPA_3 162 137 5563 4336 57.97 57.88 SPC_3 172 173 5804 4847 59.47 58.25 SPA_3.5 163 138 5705 4442 76.02 66.54 SPC_3.5 163 165 5463 5185 76.63 83.03 SPA_4 161 144 6151 4825 84.82 80.30 SPC_4 172 174 5839 6015 86.26 92.66 SPB_3 175 168 5850 4669 57.78 57.18 SPAl_3 198 184 10981 6985 50.84 58.03 SPB_3.5 165 160 5555 5025 81.11 78.35 SPAl_3.5 199 185 11789 8261 78.45 76.62 SPB_4 170 164 6045 4935 85.00 78.14 SPAl_4 193 184 11061 10030 99.20 100.30 Table 2 : Parameters of impacted sandwich panels. D