Recent Progress on Additive Manufacturing of Piezoelectric Ceramics

doi:10.15541/jim20210358

Abstract

Abstract:

Piezoelectric ceramic is a type of functional ceramic, which is able to convert the mechanical signal and the electronic signal mutually. Composed of piezoelectric ceramics and organic phase, piezoelectric composites have different kinds of connectivities, which not only determine the diverse applications of piezoelectric devices, but also promote the development of various shaping techniques in manufacturing piezoelectric materials and devices. In comparison with the traditional shaping methods, the most distinguishable advantage of additive manufacturing lies in its ability of quickly shaping a small batch of samples into geometrically complex designs without a mould, which makes it a highly suitable technique for investigating piezoelectric ceramics and its derivative devices in different kinds of connectivities. Meanwhile, the final additively manufactured samples require only tiny post-processing, have a high rate of utilization of the raw material and do not need cutting fluid during manufacturing. Due to the above-mentioned advantages, it attracts the widespread concerns from both academic and industrial communities. When focusing in the field of additive manufacturing ceramics, the data of scientific reports in additive manufacturing functional ceramics and devices prove that it is still in a growing period. In the perspective of different additive manufacturing techniques, this article discusses and compares additive manufacturing of both lead-free and lead-based piezoelectric ceramics in the aspects of their historical development of each technique, preparation of the raw materials, geometrical designs, measurement of functional properties, and applications of the printed samples, and forecasts the future development based on the current benefits and drawbacks of each additive manufacturing technique.

Key words: additive manufacturing, lead-based piezoceramics, lead-free piezoceramics, functional property, review

CLC Number:

TM282

NAN Bo, ZANG Jiadong, LU Wenlong, YANG Tingwang, ZHANG Shengwei, ZHANG Haibo. Recent Progress on Additive Manufacturing of Piezoelectric Ceramics[J]. Journal of Inorganic Materials, 2022, 37(6): 585-595.

Figures/Tables 8

Fig. 1 Connectivities of piezoelectric ceramics and schematic pictures of common AM techniques applied for preparing piezoelectric ceramics (a) 10 types of connectivitities in bi-phase composites[10]; (b) Vat photopolymerization[18]; (c) Direct ink writing[21]; (d) Inkjet printing[23]; (e) Fused deposition modelling[26]; (f) Binder jetting[29]

Table 1 Comparison of advantages and disadvantages and composition of the feedstocks among several AM techniques applied in ceramics

AM techniques	Advantages	Disadvantages	Ingredients of raw materials	Binder system	Ref.
Vat photo- polymerization (VP)	Low surface roughness, high printing accuracy	High cost of ceramic paste and machine, low degree of open source	Photosensitive polymer + ceramic powder/ceramic precursor	Photosensitive polymer	[18-20]
Direct ink writing (DIW)	Open source, multi-materials printing	Clogging of nozzles, high surface roughness	Powder + polymer solution (high viscosity)/ceramic precursor	Water/oil based	[21-22]
Inkjet printing (IP)	Open source, high printing accuracy	Low solids loading, easy precipitation of the particles	Powder + polymer solution (low viscosity)/ceramic precursor	Water/oil based	[23-25]
Fused deposition modelling (FDM)	Open source, low cost of the machine	Low relative density, low accuracy	Ceramic powder + polymer (filament)	Thermal plastic polymers	[26-28]
Binder jetting (BJ)	High quality, gradient materials	High cost of machine, reuse of the powder bed	Powder bed + polymer solution	Water/oil based	[29]

Fig. 2 Piezoelectric BT arrays with different shapes[39] (a) Dot array; (b-c) Square arrays with different sized void spaces; (d) Honeycomb array

Fig. 3 Design of piezoelectric metamaterials for tailorable piezoelectric charge constants[44] (a-g): Node unit designs from 3-, 4-, 5- and 8-strut identical projection patterns, respectively; (h) Node unit with dissimilar projection patterns showing decoupled $\bar{d}_{31}$, $\bar{d}_{32}$; (i) Dimensionless piezoelectric anisotropy design space accommodating different 3D node unit designs with distinct d3M distributions

Fig. 4 Macrostructure, microstructure and application of piezoelectric ceramics prepared by direct ink writing (a-c) PZT in 3-3, 3-2 and 3-1 connectivity (upper and lower pictures show the surface and cross-section of the sample, respectively)[56]; (d) Linear and annular samples with a size bar of 5 mm; (e) Cross-section of LA-2 in (d)[57]; (f) Captured image of 12 LEDs driven by the capacitor charged by KNN/PDMS[59]; (g) Alizarin Red staining of BST/40% β-TCP composite, indicating the maximum mineral deposition with a good biomineralization activity[65]

Fig. 5 Different heights of pillar arrays made by ink-jet printing[71] (a) Sample printed in 1000 layers; (b) Sample printed in 4000 layers

Fig. 6 Macrostructures and microstructures of samples prepared by fused deposition modelling (a) 3-3 porous ladder sample[85]; (b) Wax mould[85]; (c) 1-3 pillar arrays made by lost mould process (mould in (b))[85]; (d) 2-2 linear sample[86]; (e) Left showing 2-2 annular ring and right showing 3-3 ladder structures[85]

Table 2 Functional properties of piezoelectric ceramics made by AM

Material	AM techniques	Connectivities	ε_r	tanδ	Poling conditions	d₃₃/(pC·N^-1)	k_t	Ref.
BT	VP	1-3	1350	-	30 kV·cm^-1, 100 ℃ 30 min	160	0.474	[40]
BT	VP	1-3	920	0.07	2 V·μm^-1, 120 ℃ 30 min	87	0.3	[19]
PZT	VP	1-3	1040	0.020	30-40 kV·cm^-1, 70 ℃ 15 min, silicone oil	345	0.53	[45]
PZT	DIW	Concentric ring	1081	-	25 kV·cm^-1, room temperature 30 min	496	-	[57]
KNN	DIW	3-3	1775	-	2.5 kV·mm^-1, 100 ℃ 20 min, silicone oil	280	-	[58]
BT	DIW	Bulk	4730	0.033	0.66 MV·m^-1, 80 ℃ 15 h, silicon oil	200	-	[60]
BCZT	DIW	3-3	1046	0.021	3 kV·mm^-1, room temperature 30 min, silicon oil	(100±4)	-	[63]
Nb-PZT	IP	2-2	~700	~0.04	4 kV·mm^-1, 120 ℃ 40 min, silicon oil	-	0.46	[77]
PZT	FDM	3-3	700	-	25 kV, 70 ℃ 15-20 min, Corona technique	(290±10)	0.5	[85]
PZT	FDM	2-2	627	0.023	26 kV, 60 ℃ 15 min, Corona technique	(397±16)	0.68, 0.32(k_p)	[86]

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