A kind of sodium potassium niobate-based lead-free piezoelectric ceramic and preparation method thereof

A technology based on lead-free piezoelectric and sodium potassium niobate, applied in the field of piezoelectric ceramic devices, can solve the problems of deviation of sintered ceramic components from the designed stoichiometric ratio, difficulty in obtaining high voltage, electromechanical properties, and difficulty in preparing KNN ceramics. , to achieve the effects of removing damage to human health and social environment, reducing porosity and increasing density

Active Publication Date: 2022-07-12
XI AN JIAOTONG UNIV
View PDF11 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Although KNN ceramics have excellent performance, it is difficult to prepare KNN ceramics. The structure of ceramic samples prepared by conventional sintering methods has high porosity and low density; in addition, K and Na are severely volatilized at high temperatures, which leads to serious deviation of the sintered ceramic components from the design. Stoichiometric ratio, difficult to obtain high voltage electrical, electromechanical properties

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • A kind of sodium potassium niobate-based lead-free piezoelectric ceramic and preparation method thereof
  • A kind of sodium potassium niobate-based lead-free piezoelectric ceramic and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0029] A high-performance sodium potassium niobate-based lead-free piezoelectric ceramic of the present invention has the chemical formula (1-x)(K 0.5 Na 0.5 )NbO 3 -xBi(Li 0.5 Sb 0.5 )O 3 , x represents the mole fraction, 0.01≤x≤0.20. Its preparation method comprises the following steps:

[0030] Step 1, pre-drying analytically pure raw materials of sodium carbonate, potassium carbonate, niobium pentoxide, bismuth oxide, lithium carbonate and antimony trioxide;

[0031] Step 2, according to (1-x)(K 0.5 Na 0.5 )NbO 3 -xBi(Li 0.5 Sb 0.5 )O 3 Each drying raw material is weighed in a stoichiometric ratio, mixed and ball-milled and dried to obtain a mixed material A;

[0032] Step 3, calcining the mixture A to obtain the calcined powder B;

[0033] Step 4, the powder synthesized after pre-sintering is ball-milled for a second time and dried to obtain a second ball-milling powder C;

[0034]Step 5, adding a binder to the secondary ball-milling powder C, granulating an...

Embodiment 1

[0049] In step 1, raw materials such as sodium carbonate, potassium carbonate, niobium pentoxide, bismuth oxide, lithium carbonate, and antimony trioxide are pre-dried in a 120° C. oven for 24 hours.

[0050] Step 2, according to the chemical formula 0.96 (K 0.5 Na 0.5 )NbO 3 -0.04Bi (Li 0.5 Sb 0.5 )O 3 The stoichiometric ratio is weighed, mixed and ball-milled, and dried after the ball-milling is completed to obtain the mixed material A. Among them, the mass ratio of raw materials to grinding balls was 1:1.5; the mass ratio of raw materials to absolute ethanol was 1:1.0, the ball milling time was 36h, and the drying temperature was 120°C.

[0051] In step 3, the drying mixture A is put into a crucible, and it is placed in a muffle furnace for calcination to obtain calcined powder B. The pre-sintering temperature is 800℃, and the holding time is 4h.

[0052] Step 4: The pre-sintered material is ball-milled for 48 hours for a second time, and granulated by adding a binde...

Embodiment 2

[0058] In step 1, raw materials such as sodium carbonate, potassium carbonate, niobium pentoxide, bismuth oxide, lithium carbonate, and antimony trioxide are pre-dried in a 100° C. oven for 5 hours.

[0059] Step 2, according to the chemical formula 0.99 (K 0.5 Na 0.5 )NbO 3 -0.01Bi (Li 0.5 Sb 0.5 )O 3 The stoichiometric ratio is weighed, mixed and ball-milled, and dried after the ball-milling is completed to obtain the mixed material A. Among them, the mass ratio of raw materials to grinding balls was 1:2.0; the mass ratio of raw materials to absolute ethanol was 1:0.5, the ball milling time was 24h, and the drying temperature was 100°C.

[0060] In step 3, the drying mixture A is put into a crucible, and it is placed in a muffle furnace for calcination to obtain calcined powder B. The pre-sintering temperature is 850℃, and the holding time is 3h.

[0061] Step 4: The pre-sintered material is ball-milled for 36 hours for a second time, and granulated by adding a binder...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
piezoelectric charge coefficientaaaaaaaaaa
piezoelectric charge coefficientaaaaaaaaaa
piezoelectric charge coefficientaaaaaaaaaa
Login to view more

Abstract

The invention discloses a sodium-potassium niobate-based lead-free piezoelectric ceramic and a preparation method thereof. The chemical formula of the potassium-sodium niobate-based piezoelectric ceramic is (1-x)(K 0.5 Na 0.5 )NbO 3 ‑xBi(Li 0.5 Sb 0.5 )O 3 , where 0.01≤x≤0.20. According to the stoichiometric ratio (1‑x) (K 0.5 Na 0.5 )NbO 3 ‑xBi(Li 0.5 Sb 0.5 )O 3 The weighed and dried raw materials are mixed and then ball-milled and dried to obtain a mixed material; the obtained mixed material in step 1 is pre-burned at a high temperature to obtain a pre-burned powder, and then ball-milled and dried for a second time to obtain a secondary ball-milled powder; Add binder to the powder for granulation, and then sieve and then press and shape to obtain a ceramic blank; remove the organic binder and then sinter at high temperature to obtain a sintered ceramic; the two surfaces of the sintered ceramic are polarized by silver and high pressure , the sodium potassium niobate-based lead-free piezoelectric ceramics were obtained. Through component design and process optimization, the sintering characteristics of sodium potassium niobate-based ceramics are effectively improved, the volatilization of sodium and potassium elements is inhibited, the porosity is reduced, the density of ceramics is improved, and the dielectric constant is increased, the loss is reduced, and the Comprehensive properties of KNN-based ceramics.

Description

technical field [0001] The invention belongs to the technical field of piezoelectric ceramic devices. In particular, a sodium potassium niobate-based lead-free piezoelectric ceramic and a preparation method thereof are provided. Background technique [0002] With the rapid development of electronic information technology, people have higher and higher requirements for the performance, appearance and convenience of electronic products such as mobile phones and personal computers. High-performance capacitors are important electronic components to meet market demand. Therefore, it is urgent to develop new ceramic capacitors with high dielectric constant, low loss and wide temperature range. [0003] At present, lead-based electronic ceramic materials represented by lead zirconate titanate (PZT for short) occupy most of the application market and are widely used in piezoelectric devices such as capacitors, sensors, actuators, transformers and ultrasonic transducers. However, t...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Patents(China)
IPC IPC(8): C04B35/495C04B35/622C04B35/638C04B35/64
CPCC04B35/495C04B35/622C04B35/638C04B35/64C04B2235/3201C04B2235/3203C04B2235/3298C04B2235/3294C04B2235/6562C04B2235/6567
Inventor 李景雷罗力晨王明文杨帅吴杰李飞
Owner XI AN JIAOTONG UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap