Method for preparing compact polycrystalline diamond and boron-doped polycrystalline diamond

A polycrystalline diamond and boron-doped technology, which is applied in the field of boron-doped polycrystalline diamond, can solve the problems of high price and unacceptable market, and achieve the effects of improving performance, reducing synthesis pressure, and reducing synthesis time

Active Publication Date: 2020-07-17
YANSHAN UNIV
View PDF11 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] Unfortunately, harsh synthesis conditions (≥15GPa and 2300°C) limit the industrial production of nano-polycrystalline diamond, and a small amount of production is also difficult to accept in the market due to the high cost of the price.

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 preparing compact polycrystalline diamond and boron-doped polycrystalline diamond
  • Method for preparing compact polycrystalline diamond and boron-doped polycrystalline diamond
  • Method for preparing compact polycrystalline diamond and boron-doped polycrystalline diamond

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0039] (1) Firstly, carbon nano-onions with diamond cores (particle size: 2-20nm) prepared from industrial detonation nano-diamonds by vacuum annealing (vacuum degree 1Pa, annealing temperature 1300°C, no heat preservation), mixed with mass The percentage is 3% (accounting for the sum of carbon nano-onions and elemental boron mass) elemental boron, which is uniformly mixed by ball milling under an inert environment;

[0040] (2) Utilize the hydraulic press to preliminarily pre-press the uniform mixture, with a pressure of 500 MPa and room temperature;

[0041] (3) The preliminary pre-pressed sample prepared in step (2) was pre-pressed twice under high pressure using a domestic six-sided top press, the molding pressure was 5GPa, and the temperature was 800°C to obtain a preform;

[0042] (4) Use the domestic six-sided roof to install the 6-8 multi-stage supercharging device to generate the preformed material obtained by high temperature and high pressure (8GPa and 1800°C); the ...

Embodiment 2

[0052] (1) First, the carbon nano-onions (the annealing conditions are the same as in Example 1, and the particle size is 2 to 20nm) prepared by industrial detonation nano-diamonds through vacuum annealing, the doping mass percentage is 1% ( Accounting for the sum of the mass of carbon nano-onions and elemental boron), the elemental boron is uniformly mixed by means of ball milling under an inert environment;

[0053] (2) Utilize the hydraulic press to preliminarily pre-press the uniform mixture, with a pressure of 500 MPa and room temperature;

[0054] (3) The preliminary pre-pressed sample prepared in step (2) was pre-pressed twice under high pressure using a domestic six-sided top press, and the molding pressure was 5GPa, and the temperature was 600°C to obtain a preform;

[0055] (4) Use the domestic six-sided roof to install the 6-8 multi-stage supercharging device to generate the preformed material obtained by high temperature and high pressure (10GPa and 2000°C); the hi...

Embodiment 3

[0063] (1) Firstly, the carbon nano-onions (the annealing conditions are the same as in Example 1, and the particle size is 2 to 20nm) prepared by industrial detonation nano-diamonds through vacuum annealing, the doping mass percentage is 10% ( Accounting for the sum of the mass of carbon nano-onions and elemental boron) elemental boron is uniformly mixed by means of ball milling under an inert environment;

[0064] (2) Utilize the hydraulic press to preliminarily pre-press the uniform mixture, with a pressure of 500 MPa and room temperature;

[0065] (3) The preliminary pre-pressed sample prepared in step (2) was pre-pressed twice under high pressure by using a domestic six-sided top press, with a molding pressure of 3GPa and a temperature of 600°C to obtain a preform;

[0066] (4) Preforms obtained by direct high-temperature and high-pressure treatment (5GPa and 1200°C) using domestic six-sided roof; Raise the temperature to 1200°C at a heating rate of 1,200°C, hold the tem...

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
particle diameteraaaaaaaaaa
sizeaaaaaaaaaa
hardnessaaaaaaaaaa
Login to view more

Abstract

The invention provides a method for preparing compact polycrystalline diamond and boron-doped polycrystalline diamond, and relates to the technical field of high-performance materials. The method comprises the steps: mixing carbon nano onion with a diamond core with a boron source to obtain a mixture, wherein the boron source is elemental boron or boron oxide; then carrying out primary prepressingforming and secondary high-pressure prepressing forming on the mixture in sequence, and thus obtaining a preformed material; and carrying out high-temperature and high-pressure sintering on the preformed material to obtain a compact boron-doped polycrystalline diamond block, wherein the conditions of high-temperature and high-pressure sintering comprise that the sintering temperature is 1200-2000DEG C, the sintering pressure is 5-10 GPa, and the heat and pressure maintaining time is 1-200 min. The carbon nano onion with the diamond core is used as a carbon raw material, and the boron elementis doped, so that the synthesis condition of the polycrystalline diamond can be greatly reduced, and the method is suitable for industrial production; and the performance of the polycrystalline diamond is improved.

Description

technical field [0001] The invention relates to the technical field of high-performance materials, in particular to a method for preparing dense polycrystalline diamond and a boron-doped polycrystalline diamond. Background technique [0002] Diamond is the hardest material known in the world. Since the artificial synthesis of diamond in the 1950s, diamond and its products have been widely used in the field of processing, such as cutting and grinding tools. However, synthetic diamond cannot be directly used as a cutting tool due to its fine particles, and isotropic polycrystalline diamond is usually obtained by sintering diamond micropowder through powder sintering. However, based on thermodynamic considerations, diamond is a metastable phase at atmospheric pressure, and a certain high temperature will promote its transformation into graphite. At the same time, diamond has a very high decomposition temperature, which means that it is not feasible to obtain polycrystalline d...

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): C04B35/52C04B35/622C04B35/645
CPCC04B35/52C04B35/622C04B35/645C04B2235/421C04B2235/6562C04B2235/6567C04B2235/6581C04B2235/662C04B2235/96
Inventor 王明智唐虎袁小红
Owner YANSHAN 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