Acoustic and electrical properties of 1–3 connectivity bismuth sodium titanate–Portland cement composites

• New smart composites for structural health monitoring were developed.
• Acoustic impedance of the composites was calculated and shows to match concrete.
• These composites are environmental friendly piezoelectric sensors.
• These composites were fabricated with 1–3 connectivity to improve properties.
• High piezoelectric voltage coefficient (g33) values were found.

In this study, bismuth sodium titanate (BNT)–Portland cement (PC) composites with 1–3 connectivity pattern were fabricated by the dice-and-fill technique with different BNT ceramic content ranging from 30 to 70 vol%. The acoustic impedance (Zc) and electrical properties of the composites were studied. When the BNT content varies from 30 to 70 vol%, Zc value increases from 8.95 to 14.79 × 106 kg/m2 s. At BNT ceramic content of 70 vol%, dielectric constant (ϵr), electromechanical coupling coefficients (Kt) and piezoelectric coefficient (d33) are 346, 21.28% and 70 pC/N, respectively. Interestingly, the piezoelectric voltage coefficient (g33) values exhibited an opposite trend, that is, the g33 value decreases as the BNT content increases. Therefore, 1–3 connectivity of bismuth sodium titanate–Portland cement composites can be tailored by adjusting the piezoelectric ceramic content in composite; the developed composites have potential to be used as sensors for structural health monitoring applications in smart structures.

Figure optionsDownload as PowerPoint slide