US-12624228-B2 - Piezoceramic pastes with high ceramic content and method for printing same

Abstract

The present disclosure is directed towards a formulation for piezoelectric materials. The formulation may be printed including 2D or 3D printing. The formulation contains ceramic particles, a sol-gel, a high boiling point solvent and a binder.

Inventors

• Chantal Paquet
• Silvio Elton Krüger
• Thomas Lacelle
• Derek ARANGUREN VAN EGMOND
• Claudie ROY

Assignees

• NATIONAL RESEARCH COUNCIL OF CANADA

Dates

Publication Date

20260512

Application Date

20210824

Claims (19)

1. 1 . A 3-D printable paste formulation comprising: ceramic particles; 10-20 wt. % of a sol-gel, based on total weight of the formulation; a high boiling point solvent having a boiling point of at least 100° C.; and, a binder, wherein the ceramic particles have an average particle diameter of 500 nm or greater, and wherein the formulation forms a self-supporting structure on printing and has a viscosity of 15,000 cP to 230,000 cP as measured when printing shear rates are in a range of 5-10 s −1 .
2. 2 . The formulation of claim 1 wherein, the binder is a polymer binder.
3. 3 . The formulation of claim 1 wherein the binder is polyvinylpyrrolidone, polyacrylic acid, polyvinyl alcohol, polyethyleneglycol or any combination thereof.
4. 4 . The formulation of claim 1 , wherein the binder is present in the formulation in an amount in a range of 0.05-5 wt. %, based on the total weight of the formulation.
5. 5 . The formulation of claim 1 , wherein the ceramic particles comprise lead zirconate titanate (PZT) particles or particles of materials having perovskite structures, or any combination thereof.
6. 6 . The formulation of claim 1 , wherein the ceramic particles comprise BaTiO 3 , KNbO 3 , ZnO, BiFO 3 , Bi 4 Ti 3 O 12 or any combination thereof.
7. 7 . The formulation of claim 1 , wherein the ceramic particles are PZT particles.
8. 8 . The formulation of claim 1 , wherein the ceramic particles are present in the formulation in an amount in a range of 40-80 wt. %, based on total weight of the formulation.
9. 9 . The formulation of claim 1 , wherein the sol-gel comprises nanoparticles of PZT, BaTiO 3 , KNbO 3 , ZnO, BiFO 3 , Bi 4 Ti 3 O 12 or any combination thereof.
10. 10 . The formulation of claim 1 , wherein the high boiling point solvent comprises an alcohol.
11. 11 . The formulation of claim 1 , wherein the high boiling point solvent has a boiling point in a range of 100° C. to 250° C.
12. 12 . The formulation of claim 1 , wherein the high boiling point solvent comprises 1-butanol, 2-methyl-2-propanol, 1-pentanol, 3-methyl-1-butanol, 2,2-dimethyl-1-propanol, cyclopentanol, 1-hexanol, cyclohexanol, 1-heptanol, 1-octanol, propylene carbonate, tetraglyme, 2-(2-methoxyethoxy) acetic acid or any combination thereof or any mixture thereof.
13. 13 . The formulation of claim 1 , wherein the solvent is present in the formulation in an amount in a range of 3.5-35 wt. %, based on total weight of the formulation.
14. 14 . The formulation of claim 1 having a viscosity of 15,000 cP to 200,000 cP as measured when printing shear rates are in a range of 5-10 s −1 .
15. 15 . The formulation of claim 1 , wherein the self-supporting structure has a yield stress 100 Pa or greater.
16. 16 . A process for producing a piezoelectric material comprising depositing the formulation of claim 1 onto a substrate.
17. 17 . The process of claim 16 , wherein said depositing comprises printing.
18. 18 . The process of claim 17 wherein said printing comprises 2D printing, 3D printing or a combination thereof.
19. 19 . The process of claim 16 , wherein the depositing comprises direct-write or extrusion 3D-printing.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a national entry of PCT/CA2021/051173 filed Aug. 24, 2021 and claims the benefit of U.S. Provisional Application 63/069,253 filed Aug. 24, 2020, the entire contents of both of which are herein incorporated by reference. FIELD This application relates to piezoceramic pastes. More particularly, the present application relates to piezoceramic pastes with high ceramic content and methods for printing same. BACKGROUND Piezoelectric materials are able to convert mechanical pressure into electric potential (e.g., pressure sensor) and by the inverse piezoelectric effect, electric potential to a mechanical distortion (FIG. 1). They are widely used as sensors, actuators and energy harvesters in sectors such as aerospace, mining, nuclear, oil and gas as well as biomedical applications. Despite their commercial success, broader application of piezoelectric ceramics is limited by two disadvantages. First, ceramic piezoelectric materials tend to be brittle and fragile resulting in poor device reliability and limitations in processability. Second, ceramic devices use expensive or complex manufacturing processes, such as sputtering, that require highly controlled heating and sintering at high temperatures (>250° C.), along with energy intensive steps such as cutting, milling, or grinding, rendering them cost prohibitive or impractical for many applications. There are emerging needs to manufacture high volume of embedded sensors to obtain more accurate sensing data. The current production methodologies of piezoelectric ceramics (e.g., lead zirconate titanate (PZT)) often entail numerous steps to their preparation processing, and are labor and time intensive with low freedom to modify design parameters. Commercial products that provide the manufacturing solutions, such as those based on PVDF polymers, do not meet the performance requirements needed for most sensing applications. Therefore, there is a need for material processing that is additive, allowing increased design freedom and ease of integration into parts. SUMMARY In an aspect of the present disclosure, there is provided a formulation comprising: a binder; ceramic particles and a sol-gel. In another aspect, the above formulation comprises a polymer binder. In another aspect, the binder is polyvinylpyrrolidone, polyacrylic acid, polyvinyl alcohol, polyethyleneglycol or any combination thereof. In another aspect, the ceramic particles are selected from the group consisting of PZT particles or particles of materials having perovskite structures, or any combination thereof. In another aspect, the ceramic particles are particles BaTiO3, KNbO3, ZnO, BiFO3, Bi4Ti3O12 or any combination thereof. In another aspect, the ceramic particles are PZT particles. In another aspect, the sol-gel comprises PZT, BaTiO3, KNbO3, ZnO, BiFO3, Bi4Ti3O12 or any combination thereof. In another aspect, the above formulation comprises 40-80 wt. % of the ceramic particles based on the total weight of the formulation. In another aspect, the above formulation comprises 0.05-5 wt. % of the binder based on the total weight of the formulation. In another aspect, the above formulation comprises 10-20 wt. % of the sol-gel, based on the total weight of the formulation. In another aspect, the above formulation is a printing paste In an aspect of the present disclosure, there is provided a formulation comprising: a high boiling point solvent; ceramic particles and a sol-gel. In another aspect, the above high boiling point solvent comprises 1-butanol, 2-methyl-2-propanol, 1-pentanol, 3-methyl-1-butanol, 2,2-dimethyl-1-propanol, cyclopentanol, 1-hexanol, cyclohexanol, 1-heptanol, 1-octanol, propylene carbonate, tetraglyme, 2-(2-methoxyethoxy)acetic acid or any combination thereof. In another aspect, the above formulation further comprises a binder. In another aspect, the above binder is a polymer binder. In another aspect, the above binder comprises polyvinylpyrrolidone, polyacrylic acid, polyvinyl alcohol, polyethyleneglycol or any combination thereof. In another aspect, the above formulation is a printing paste. In another aspect of the present disclosure, there is provided a formulation comprising: ceramic particles; a sol-gel; a high boiling point solvent; and, a polymer binder. In another aspect, there is provided a process for producing a piezoelectric material comprising providing the above formulation and depositing the above formulation onto a substrate. In another aspect, the above depositing comprises printing. In another aspect, the above printing comprises 2D printing, 3D printing or a combination thereof. In another aspect, the above depositing comprises 3D-printing using extrusion, direct writing or stereolithography. Further features will be described or will become apparent in the course of the following detailed description. It should be understood that each feature described herein may be utilized in any combination with any one o