Method for sintering multiferroic bismuth ferrite-based electronic functional ceramics

A technology of functional ceramics and bismuth ferrite, which is applied in the field of functional ceramics, can solve the problems of high calcination temperature, easy mixing, and failure to obtain powder, and achieve low discharge plasma sintering temperature, good phase structure and compactness, and piezoelectricity. sex enhancing effect

Inactive Publication Date: 2014-08-27
HOHAI UNIV
View PDF4 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

But this method also has many unavoidable shortcomings: (1) each component in the raw material is difficult to mix to ideal homogeneous state; (2) calcining temperature is high; Sintered body with metering ratio; (4) It is easy to be mixed in the whole process, and powder with high purity cannot be obtained, which will eventually affect the performance of the material
Conventional sintering is currently the most commonly used sintering method in the production of ceramic materials, but the relative density of sintered ceramic sheets is relatively low, which cannot fully meet the needs of high-performance products; reaction sintering is limited to a few systems: silicon nitride, oxygen nitrogen Silicon carbide, silicon carbide, etc., it can produce products with complex shapes and precise dimensions, the process is simple, economical, and suitable for mass production, but the density of the sintered compact is low, and the mechanical properties of the material are not high; hot pressing sintering uses a special hot press machine, Single-phase or two-phase pressure is completed at high temperature, and products with almost no pores can be obtained, but only products with simple shapes can be produced. At the same time, the microstructure after hot pressing and sintering is anisotropic, resulting in anisotropic performance. Limits its scope of use, in addition, due to high hardness, subsequent processing of hot-pressed products is particularly difficult
[0007] The above sintering method has the disadvantages of low relative density and many impurity phases in the preparation of multiferroic ceramic materials, and it is difficult to guarantee the performance of sintered samples

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
  • Method for sintering multiferroic bismuth ferrite-based electronic functional ceramics
  • Method for sintering multiferroic bismuth ferrite-based electronic functional ceramics
  • Method for sintering multiferroic bismuth ferrite-based electronic functional ceramics

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0027] Will Fe 2 o 3 、 Bi 2 o 3 、BaCO 3 、TiO 2 and MnO 2 Mix and ball mill for 15 hours at a molar ratio of 39:39:22:22:0.4, dry, press into tablets, place the pressed columnar block in a sintering furnace for sintering, and pre-sinter at 850°C for 5 hours , cooled naturally; the pre-sintered ceramic sheets were crushed and ball-milled into powder, then pressed into tablets, and the pressed columnar block was sintered in a sintering furnace, solid-phase sintered at 950 ° C for 2 hours and then cooled naturally to obtain a solid Phase-sintered ceramic sheets; turn on the cooling water of the sintering furnace, crush the prepared solid-phase sintered ceramic sheets and put them into the sintering chamber, apply an axial pressure of 50 MPa at both ends, and vacuumize, and the air pressure of the sintering chamber is 80Pa Start heating when the vacuum degree is reached, and the heating rate is 100°C / min. When the temperature rises to 650°C, start discharge plasma sintering a...

Embodiment 2

[0030] Will Fe2 o 3 、Bi 2 o 3 、BaCO 3 、TiO 2 and MnO 2 Mix and ball mill at a molar ratio of 34:34:32:32:0.4 for 20 hours, dry, press into tablets, place the pressed columnar block in a sintering furnace for sintering, and pre-sinter at 880°C for 6 hours , natural cooling; the pre-sintered ceramic sheet is crushed and ball-milled into powder, then pressed into a tablet, the pressed columnar block is placed in a sintering furnace for sintering, solid-phase sintering at 960 ° C for 3 hours and then naturally cooled to obtain a solid Phase-sintered ceramic sheets; turn on the cooling water of the sintering furnace, crush the prepared solid-phase sintered ceramic sheets and put them into the sintering chamber, apply an axial pressure of 50 MPa at both ends, and vacuumize, and the air pressure of the sintering chamber is 80 Pa Start heating when the vacuum degree is reached, and the heating rate is 100°C / min. When the temperature rises to 660°C, start discharge plasma sinterin...

Embodiment 3

[0032] Will Fe 2 o 3 、Bi 2 o 3 、BaCO 3 、TiO 2 and MnO 2 Mix and ball mill for 10 hours at a molar ratio of 40:40:20:20:0.4, dry, press into tablets, place the pressed columnar block in a sintering furnace for sintering, and pre-sinter at 800°C for 3 hours , cooled naturally; the pre-sintered ceramic sheets were crushed and ball-milled into powder, then pressed into tablets, and the pressed columnar blocks were sintered in a sintering furnace, solid-phase sintered at 900°C for 2 hours, and then cooled naturally to obtain a solid Phase-sintered ceramic sheets; turn on the cooling water of the sintering furnace, crush the prepared solid-phase sintered ceramic sheets and put them into the sintering chamber, apply an axial pressure of 30MPa at both ends, and vacuumize, and the air pressure of the sintering chamber is 80Pa Start heating when the vacuum is high, and the heating rate is 50°C / min. When the temperature rises to 630°C, start discharge plasma sintering and keep it f...

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
Granularityaaaaaaaaaa
Piezoelectric coefficientaaaaaaaaaa
Login to view more

Abstract

The invention provides a method for sintering multiferroic bismuth ferrite-based electronic functional ceramics, which comprises the following steps: mixing Fe2O3, Bi2O3, BaCO3, TiO2, and MnO2 powder according to a mole ratio of 34-40:34-40:20-32:20-32:0.4, performing ball milling, drying, tabletting, and presintering in a sintering furnace; crushing the presintered ceramic chips, performing ball milling to obtain powder, and performing solid-phase sintering; crushing the ceramic chip after solid-phase sintering, and performing ball milling and spark plasma sintering. The multiferroic bismuth ferrite-based electronic functional ceramics prepared by the invention have very good phase structure and compactness, and have significantly improved ferroelectricity and piezoelectricity. The process is simple; the spark plasma sintering temperature is low; and the production is safer.

Description

technical field [0001] The invention belongs to the field of functional ceramics, in particular to a method for sintering multiferroic bismuth ferrite-based electronic functional ceramics. Background technique [0002] Electronic functional ceramics refer to ceramic materials whose main features are the detection, conversion, coupling, transmission and storage of electricity, magnetism, light, sound, heat, force, chemical and biological information, mainly including piezoelectric, dielectric, Superconducting and magnetic ceramics, etc. Electronic ceramics occupy a very important position in miniaturized and portable electronic products. Component manufacturers all over the world have invested heavily in new products, new technologies, new processes, new materials, and new equipment for electronic ceramics and their components. research and develop. Every year, a large number of new functional ceramic materials and components come out. [0003] The unique performance of el...

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
IPC IPC(8): C04B35/26C04B35/622
Inventor 戴中华周娟
Owner HOHAI 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