Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Tantalum powder, method for preparing the same, and electrolytic capacitor anode made of the tantalum powder

a technology of tantalum powder and tantalum powder, which is applied in the field of tantalum powder and the preparation of the same, can solve the problems of high cost, difficult control, and poor tolerance of tantalum powder, and achieve excellent dc leakage performance and high specific capacitan

Inactive Publication Date: 2010-09-09
NINGXIA ORIENT TANTALUM IND
View PDF4 Cites 21 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

[0010]Still another object of the present invention is to provide tantalum powder with excellent performance on DC leakage.
[0012]In order to achieve said objects, the inventors find that, by changing the type of morphology of tantalum powder which is added as seed in the reducing process, the particle morphology of the product tantalum powder and the porosity of the anode can be improved, and thus the properties, including DC leakage and breakdown voltage could be improved, whereby the tantalum powder that can be used in the high voltage electrolytic capacitor is obtained.

Problems solved by technology

The tantalum powder having poor tolerance of high voltage can hardly be used for high voltage field.
WO 93 / 03,191, U.S. Pat. No. 4,740,238, U.S. Pat. No. 5,211,741, U.S. Pat. No. 5,261,942 disclosed improved flake tantalum powder and processes for producing flake tantalum powder, but the processes are complex, difficult to control, and the cost is high, thus the application of these technologies is limited.

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
  • Tantalum powder, method for preparing the same, and electrolytic capacitor anode made of the tantalum powder
  • Tantalum powder, method for preparing the same, and electrolytic capacitor anode made of the tantalum powder
  • Tantalum powder, method for preparing the same, and electrolytic capacitor anode made of the tantalum powder

Examples

Experimental program
Comparison scheme
Effect test

example 1

[0041]Sample A (not according to the present invention): obtained directly by sodium reduction;

[0042]Sample B (according to the present invention): obtained with addition of 10 mass % seed tantalum powder in the reduction;

[0043]Sample C (according to the present invention): obtained with addition of 20 mass % seed tantalum powder in the reduction.

TABLE 1Specific surface area, bulk density and Fishermean particle size of the samples A, B and CSpecific surfaceBulk densityFisher mean particleSamplearea (cm2 / g)(g / cm3)size (μm)A0.53281.843.05B0.51201.783.15C0.48751.763.12

TABLE 2The distribution of the particle size of the samples A, B andC (all percentages are expressed by vol. %, same hereinafter)Sample+60(%)−60 / +200(%)−200 / +325(%)−325 / +400(%)−400(%)A0.4627.5810.4215.8645.68B0.3628.1212.3213.4645.74C0.4830.2615.4613.8839.92

[0044]An amount of 0.5 g of the tantalum powder from Samples A, B and C were respectively pressed into pellets having a density of 5.0 g / cm3. The pellets were sintere...

example 2

[0045]Sample D (not according to the present invention): obtained directly by sodium reduction

[0046]Sample E (according to the present invention): obtained with addition of 30 mass % seed tantalum powder in the reduction

[0047]Sample F (according to the present invention): obtained with addition of 50 mass % seed tantalum powder in the reduction

TABLE 6The specific surface area, bulk density and Fishermean particle size of the samples D, E and F.Specific surface areabulk densityFisher mean particle sizeSample(cm2 / g)(g / cm3)(μm)D0.52381.822.90E0.46621.683.30F0.45841.633.35

TABLE 7The particle size distribution of the samples D, E and F.Sample+60(%)−60 / +200(%)−200 / +325(%)−325 / +400(%)−400(%)D0.5626.6210.8616.4245.54E0.6230.1222.3212.8034.14F0.3631.8621.4613.2033.12

[0048]An amount of 0.5 g of the tantalum powder from samples D, E and F were respectively pressed into pellets having density of 5.0 g / cm3. The pellets were sintered in a vacuum furnace at a pressure of 10−3 Pa, at different temp...

example 3

[0050]Sample H (not according to the present invention): obtained directly by sodium reduction

[0051]Sample I (according to present invention): obtained with addition of 50 mass % seed tantalum powder in the reduction

[0052]Sample J (according to present invention): obtained with addition of 70 mass % seed tantalum powder in the reduction

TABLE 14The specific surface area, apparent density and Fishermean particle size of the samples H, I and J.surface areabulk densityFisher mean particle sizeSample(cm2 / g)(g / cm3)(μm)H0.53481.802.98I0.45681.663.28J0.45321.603.30

TABLE 15The particle size distributions of the samples H, I and J (vol. %).Sample+60−60 / +200−200 / +325−325 / +400−400H0.5625.5211.3814.9847.56I0.3630.9824.6611.8832.12J0.5232.8627.5210.2428.86

[0053]An amount of 0.5 g of said powder samples H, I and J were respectively pressed into pellets having density of 5.0 g / cm3. The pellets were sintered in a vacuum furnace at a pressure of 10−3 Pa, at different temperatures of 1450° C., 1500° C...

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
Temperatureaaaaaaaaaa
Timeaaaaaaaaaa
Timeaaaaaaaaaa
Login to View More

Abstract

The present invention relates to the tantalum powder and the process for preparing the same, and also relates to the electrolytic capacitor anode made of the tantalum powder. More particularly, the present invention relates to the tantalum powder having a BET surface area not more than 0.530 m2 / g, Fisher mean particle size not less than 3.00 μm. The present invention relates to the process for preparing the tantalum powder, wherein the tantalum powder is prepared through reducing tantalum compound with a reducing agent, wherein the tantalum powder as seed is added during reduction, and said tantalum powder as seed is the tantalum powder that has been milled.

Description

FIELD OF THE INVENTION[0001]The present invention relates to tantalum powder and the preparation of the same, and also relates to the electrolytic capacitor anode made of the tantalum powder. More particularly, the present invention relates to the improved powder for manufacturing sintered tantalum capacitor anode, and the method for preparing the same.BACKGROUND OF THE INVENTION[0002]Tantalum powder is usually prepared by means of making a tantalum metal compound reacting with a reducing agent, or hydrogenating and pulverizing the dense metal. Generally, the tantalum powder obtained by means of the former method is porous basic agglomerates having high specific surface area composed of many primary particles, and the tantalum powder obtained by the later method is of high purity, but with low specific surface area.[0003]Typically, sintered tantalum capacitor is made as following steps: compressing tantalum powder to form a pellet, sintering the pellet in a vacuum furnace to form a ...

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): H01G9/042C22C27/02B22F9/20B22F1/052
CPCB22F1/0014H01G9/0525H01G9/042B22F9/24B22F1/052
Inventor YANG, GUOQISHI, WENFENGBAO, XIFANGLI, YONGLI, ZHONGXIANGDONG, ZHANGONGYANG, XIAOYAN
Owner NINGXIA ORIENT TANTALUM IND
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com