High Performance Piezoelectric and Magnetoelectric Textured Ceramics By Yongke Yan Background: Oriented relaxor-PT single crystals possess ultrahigh piezoelectric coefficient and electromechanical coupling factor k33 on the order of > 2000 pC/N and ~ 0.9 respectively, far outperforming the state-of-art Pb(Zr,Ti)O3 (PZT) polycrystalline ceramics. However, the application of single crystal has been limited due to the high production cost. To overcome the high production cost and limited size of single crystal, we have developed <001> textured relaxor-PT/PZT piezoelectric ceramics via templated grain growth (TGG) method, which show the property comparable to that of single crystal but the cost close to that of traditional ceramics. (a) (200) (210) (211) Highly Textured Ceramics: We have synthesized a series of highly textured ceramics, such as PMN-PT, PMN-PZT, and Mn doped PMN-PZT. (111) • (110) Texturing Process: A method called templated grain growth (TGG) was developed to fabricate textured ceramics. In order to obtain the textured ceramics, micro-sized template crystals are aligned in the ceramic matrix powders using tape-casting method. During high temperature sintering, epitaxial growth occurs on the template seeds giving rise to textured grains. This method is based on industrial well-established ceramic process, which guarantees low cost. (100) • (b) Intensity (a.u.) -5BT, f=0.99 <001>BT -0BT -1BT -3BT, f=0.98 111 (c) -1BT, f=0.98 001 101 -0BT, f=0 20 30 40 50 2 theta (deg.) 60 20 µm×20 µm 1 100 µm×100 µm June, 2014 High Energy Density Textured Ceramics: We have demonstrated the texture microstructure yielded a giant magnitude of d·g coefficient with value of 59000 × 10-15 m2 N-1 (comparable to that of the single crystal counterpart and 359% higher than that of the best commercial compositions). (a) 60 Company 1 Company 3 g33 (×10-3 Vm N-1) 50 (b) 6 Company 2 T-PMN-PZT 30 (ii) 20 (i) 10 BNT-based PMN-PT KNN-based T-PMN-PZT 5 (iii) 40 d33(T)/d33(R) • 4 3 2 1 0 0 200 400 600 800 1000 1200 0 300 d33 (pC N-1) • 600 900 1200 1500 1800 d33(T) (pC N-1) Radially Textured Ceramics: We have demonstrated PMN-PT cylinders with ~98% <100>C texture along the radial direction. A giant enhancement in the magnitude of electromechanical coupling factor (k31=kh=0.60, and kl=0.7) was obtained for textured cylinder, and d31×g31 was measured to be 6766×10-15 m2/N which is 3 to 6 times higher than that of commercial PZT compositions. Sample PZT-4a PZT-5Aa PZT-5Ha PZT-8a T-PMN-28PT-50%-Cb R-plate T-plate T-cylinder ε33T/ε0 1200 1700 3400 1000 2996 2781 2591 2820 tanδ 0.003 0.020 0.025 0.004 0.003 0.020 0.006 0.006 s11E 12.3 16.4 16.4 11.5 13.6 12.1 18.8 18.8 k31 0.33 0.34 0.39 0.30 0.43 0.35 0.57 0.60 2 kl 0.50 0.70 kp 0.56 0.60 0.65 0.51 0.66 0.92 d31 (pC/N) 122 171 274 97 259 208 371 411 g31 (10 Vm/N) 11.1 11.4 9.11 10.9 9.8 8.2 16.2 16.5 -3 d31×g31 (10-15 m2/N) 1354 1949 2496 1057 2538 1703 6003 6766 June, 2014 • Cofired Magnetoelectric Composite: We have demonstrated integration of textured piezoelectric with the cost-effective low-temperature co-fired layered structure to achieve strong magnetoelectric coupling. Using the co-fired composite, a strategy was developed based upon the hysteretic response of nickel-copper zinc ferrite magnetostrictive materials to achieve peak magnetoelectric response at zero DC bias, referred as self-biased magnetoelectric response. These features present significant advancement toward development of high sensitivity magnetic field sensors and energy harvesters. (a) (b) Pb Nb Ni Zn Ag Atomic percentage 100 80 60 Ag Mg Ti Cu Fe Ba Pb Fe 40 20 0 -20 0 10 20 30 (422) (511) (400) (211) (200) (210) T-PMN-PT (111) (100) Intensity (a.u.) 140 µm NCZF (222) (d) (110) (c) (220) (311) Distance (µm) R-PMN-PT Screen printing (a) 20 30 40 (b) 50 3 0.3 unit: mm 1.5 2 50 with cofired Enhanced magnetoelectric effect in longitudinal-longitudinal mode laminate green tape interdigitated electrodes: We demonstrated a low-temperature cofiring(c)technique to embed the interdigitated electrodes inside the piezoelectric ceramic layer to achieve longitudinally (L) poled magnetoelectric (ME) laminates. The ME voltage coefficient of this L-L mode composite was found to be 4.41 V cm-1 Oe-1 at 1 kHz, which is 340% higher than that of L-T (transversal) mode. IDE electrode cofired sample si gas flow in ga (d) n Aerosol jet printing sh ea th aerosol Screen printing (a) (b) 0.3 unit: mm 1.5 green tape 14 2 20 2 3 2 50 Pneumatic atomization (c) IDE electrode (e) focusd beam substrate x,y,z stage (f) cofired sample th aerosol ga si gas flow in ea (d) n Aerosol jet printing sh • 14 2 20 2 2 theta (degree) 60 3 June, 2014 • ME composite with different microstructures and connectivities: The 0–3 particulate composite can be achieved with ferrite particle well dispersed in the matrix of PZT. The αME of this composite can be obtained with the magnitude of 0.1 V/cm.Oe. By increasing the interphase contact area, this value can be further improved to ~0.2 V/cm.Oe via a core-shell structure. To minimize the leakage problem from the low resistivity ferrite phase, 2-2 ferrite/PMN-PT co-fired laminates was developed, with an significant improvement of the αME (0.8 V/cm.Oe) in compared with the 0-3 particulate ME composites. By optimizing the piezoelectric material via texturing, the αME of the cofired 2-2 laminates can be further improved to 1.3 V/cm.Oe. By utilizing longitudinal poling via the co-fired IDE, a large αME with the magnitude of 4.4 V/cm.Oe can be obtained from L-L mode. V/cm.Oe 0–3 composite 2–2 composite 4.4 (5) Cofired IDE Sintered composites only @1 kHz (4) Texturing ((3) Cofired M-P-M 1.3 (1) solid state t te sintering (2) maximized interphase contact 0.8 0.2 0.1 20nm 1 µm paticulate core-shell L-T mode L-L mode Selected Publications: l Y. Yan, Y. Zhou, and S. Priya, “Enhanced electromechanical coupling in Pb(Mg1/3Nb2/3)O3-PbTiO3 <001>C radially textured cylinders”, Applied Physics Letters, 104, 012910 (2014). l Y. Yan, K.-H. Cho, D. Maurya, et al., “Giant energy density in [001]-textured Pb(Mg1/3Nb2/3)PbZrO3-PbTiO3 piezoelectric ceramics”, Applied Physics Letters, 102, 042903 (2013). l Y. Yan, Y. Wang, S. Priya, “Electromechanical behavior of [001]-textured Pb(Mg1/3Nb2/3)O3-PbTiO3 ceramics”, Applied Physics Letters, 100, 192905 (2012) l Y. Yan, K.-H. Cho, S. Priya, “Piezoelectric properties and temperature stability of Mn-doped Pb(Mg1/3Nb2/3)-PbZrO3-PbTiO3 textured ceramics”, Applied Physics Letters, 100, 132908 (2012). l Y. Yan, K.-H. Cho, S. Priya, “Templated grain growth of <001>-textured 0.675Pb(Mg1/3Nb2/3)O3– 0.325PbTiO3 piezoelectric ceramics for magnetic field sensors”, Journal of the American Ceramic Society, 94 [6] 1784 – 179 3 (2011). l Y. Yan, Y. Zhou, and S. Priya, “Enhanced magnetoelectric effect in longitudinal-longitudinal mode laminate with cofired interdigitated electrodes”, Applied Physics Letters, 104, 032911 (2014). l Y. Yan, Y. Zhou, and S. Priya, “Giant self-biased magnetoelectric coupling in cofired textured layered composites”, Applied Physics Letters, 102, 052907 (2013). 4 June, 2014