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

Secondary-emission rare earth-molybdenum material and its preparing process

An emissive material, secondary technology, applied in the direction of electrical components, exhaust connections/feeds, gas discharge tubes/containers, etc.

Inactive Publication Date: 2002-07-24
BEIJING UNIV OF TECH
View PDF0 Cites 19 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

There are no reports about rare earth molybdenum secondary emission materials

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
  • Secondary-emission rare earth-molybdenum material and its preparing process
  • Secondary-emission rare earth-molybdenum material and its preparing process
  • Secondary-emission rare earth-molybdenum material and its preparing process

Examples

Experimental program
Comparison scheme
Effect test

example 1

[0013] Example 1, 3.32 grams of lanthanum nitrate and 11.07 grams of yttrium nitrate were dissolved in water respectively, and added to 120.02 grams of powdered MoO 2 in (where La 2 o 3 Accounting for 2.5% by weight of molybdenum, Y 2 o 3 The weight ratio of molybdenum is 7.5%), the doped MoO 2 The powder is kept at 500°C under hydrogen for 2 hours to decompose rare earth nitrates into rare earth oxides, and then doped MoO in a multi-stage hydrogen furnace at 800-1000°C 2 Powder reduced to doped La 2 o 3 and Y 2 o 3 The composite rare earth aluminum powder is made into a rare earth molybdenum rod with a certain size after pressing and sintering. After machining, a rare earth molybdenum sheet of φ10×1mm is made. Then laser welding is used to weld the rare earth molybdenum sheet with the molybdenum cylinder and the metal tungsten wire used for heating, and after exhausting and activation treatment, the rare earth molybdenum experimental magnetron is made. The secondary...

example 2

[0014] Example 2, 4.98 grams of lanthanum nitrate and 16.60 grams of yttrium nitrate were dissolved in water respectively, and added to 113.35 grams of powdered MoO 2 in (where La 2 o 3 The weight ratio of molybdenum is 3.75%, Y 2 o 3 The weight ratio of molybdenum is 11.25%), the doped MoO 2 The powder is kept at 500°C under hydrogen for 2 hours to decompose rare earth nitrates into rare earth oxides, and then doped MoO in a multi-stage hydrogen furnace at 800-1000°C 2 Powder reduced to doped La 2 o 3 and Y 2 o 3 The composite rare earth molybdenum powder is made into a rare earth molybdenum rod with a certain size after pressing and sintering. After machining, a rare earth molybdenum sheet of φ10×1mm is made. Then laser welding is used to weld the rare earth molybdenum sheet with the molybdenum cylinder and the metal tungsten wire used for heating, and after exhausting and activation treatment, the rare earth molybdenum experimental magnetron is made. The secondary...

example 3

[0015] Example 3, 6.64 grams of lanthanum nitrate and 22.14 grams of yttrium nitrate were dissolved in water respectively, and added to 106.68 grams of powdered MoO 2 in (where La 2 o 3 Accounting for 5% by weight of molybdenum, Y 2 o 3 The weight ratio of molybdenum is 15%), the doped MoO 2 The powder is kept at 500°C under hydrogen for 2 hours to decompose rare earth nitrates into rare earth oxides, and then doped MoO in a multi-stage hydrogen furnace at 800-1000°C 2 Powder reduced to doped La 2 o 3 and Y 2 o 3 The composite rare earth molybdenum powder is made into a rare earth molybdenum rod with a certain size after pressing and sintering. After machining, a rare earth molybdenum sheet of φ10×1mm is made. Then laser welding is used to weld the rare earth aluminum sheet with the molybdenum cylinder and the metal tungsten wire used for heating, and after exhausting and activation treatment, the rare earth molybdenum experimental magnetron is made. The secondary em...

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

No PUM Login to View More

Abstract

A two-element rare-earth / molybdenum material as secondary emission material is characterized by that it contains La2O3 and Y2O3 in a weight ratio of 1:3, and is preapred through adding La2O3 and Y2O3in the form of aqueous solution of their nitrates to molybdenum oxide or Mo powder, treating in hydrogen at 500-550 deg.C for 1-5 hr, reducing at 800-1000 deg.C, and powder metallurgy to obtain said secondary emission material, which has advantages of high emission coefficient, stability and mechinability and high resistance to expose in atomosphere.

Description

1. Technical field [0001] A binary rare earth molybdenum secondary emission material and a preparation method thereof belong to the technical field of rare earth refractory metal cathode materials. 2. Background technology [0002] Traditional magnetron cathode materials use Ba-W cathodes, and a small amount of Th-W cathodes. The Ba-W cathode undergoes a variety of processes such as copper infiltration, processing, pre-firing, copper removal and salt infiltration, and the production process is cumbersome. Although the secondary emission coefficient of this type of cathode is above 2.0, because the cathode is a coating type thick film The cathode has poor bombardment resistance and therefore poor emission stability. Due to the high hardness of the metal tungsten matrix, it is impossible to machine the sintered body. Th-W cathode Since Th is a radioactive element, it will cause radioactive hazards to the human body in the process of material preparation, tube loading and dis...

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 Applications(China)
IPC IPC(8): C22C1/04C22C27/04C22C32/00H01J25/50
Inventor 王金淑周美玲张久兴聂祚仁左铁镛
Owner BEIJING UNIV OF TECH
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