Fig. 3: Numerical simulation obtained acoustic wave propagation behaviors of the defective HEA sample compared with fully solid, additional damper layer, and hollow phononic crystal cases.
From: Laser-powder bed fusion printed CrMnFeCoNi high entropy alloys engineered for acoustic insulation
A1,A2,A3,A4 Models of fully solid case, with plastic damper layer, with hollow phononic crystal structure, and with random voids respectively. Noted that the solid regions in all cases have identical properties as Fig. 2F shows. B1,B2,B3,B4 Acoustic wave propagation progress at \({{{\rm{t}}}}_{1}\) when waves start to transmit into the samples from the transducers. C1,C2,C3,C4 Acoustic wave propagation progress at \({{{\rm{t}}}}_{2}\) when waves propagate around half-of-sample in fully solid case. Due to the void induced low effective sound velocity, hollow-PnC and random-voids cases show delays on the propagations. D1,D2,D3,D4 Acoustic wave propagation progress at \({{{\rm{t}}}}_{3}\) when waves about to arrive the receiver transducer in fully solid case. E1,E2,E3,E4 Acoustic wave propagation progress at \({{{\rm{t}}}}_{3}\) when waves about to arrive the receiver transducer in hollow PnC case.
