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

Method for mfg. large hole diamond coating drawing die

A diamond coating, drawing die technology, applied in metal material coating process, coating, wire drawing die and other directions, can solve the problems of increased recombination probability, decreased surface temperature, decreased coating quality and growth rate, etc., to achieve friction The effect of small coefficient and long service life

Inactive Publication Date: 2003-03-12
SHANGHAI JIAO TONG UNIV +1
View PDF2 Cites 17 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, due to the use of a single straight-drawing hot wire, when the hole diameter of the drawing die is large (> φ12 mm), the quality and deposition rate of the diamond deposited on the surface of the inner hole begin to decline significantly, further increasing the hole diameter > φ15 mm, The thickness, quality and coating adhesion of the coating will not meet the requirements of actual use
This is because, with the expansion of the pore diameter, the distance between the hot wire and the surface of the inner hole increases, and the probability of recombination of the dissociated active hydrogen atoms near the outer surface of the hot wire will greatly increase during the diffusion process to the inner hole surface, thus achieving The active hydrogen atoms on the surface of the inner pores will be greatly reduced, resulting in a decrease in the quality and growth rate of the diamond coating
In addition, since the surface of the inner hole is far away from the hot wire, its surface temperature drops, which also leads to a decrease in coating quality and growth rate

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 mfg. large hole diamond coating drawing die
  • Method for mfg. large hole diamond coating drawing die
  • Method for mfg. large hole diamond coating drawing die

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0015] In order to better understand the technical solution of the present invention, further detailed description will be given below in conjunction with the accompanying drawings and embodiments.

[0016] Such as figure 1 As shown, the squirrel-cage hot wire assembly is composed of a hot wire 1 and a round molybdenum sheet 2 for fixing the hot wire. There are 6 hot wires 1 and the round molybdenum sheet 2 is about 1.5-2 mm thick. Six small holes are evenly distributed on the edge to allow the hot wires to pass through and separate the hot wires evenly. The center of the circular molybdenum sheet 2 is fixed with a section of hot wire, and the two ports are twisted with other hot wires 1 to form a stranded hot wire 3.

[0017] The invention adopts a squirrel-cage hot wire assembly to replace the position of a single hot wire connected with the electrode, and makes the assembly axis coincide with the inner hole axis of the drawing die. In the CVD deposition process, the hot wire a...

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
surface smoothnessaaaaaaaaaa
Login to View More

Abstract

A process for preparing big-aperture draw die with plated diamond layer includes choosing the drawing hard alloy die as substrate with aperture greater than 15 mm, corroding the hole surface by diluted hydrochloric acid and H2O2, washing, and depositing diamond layer and nano diamond layer on the hole surface in a reaction chamber by electrothermal wire CVD method. In said CVD method, an electrothermal wire assembly composed of more electrothermal wires are used. Its advantages are high thickness and quality of plated layer, low friction coefficient and long service life.

Description

Technical field: [0001] The invention relates to a method for preparing a large-aperture diamond coating drawing die, which is a new method for preparing a diamond coating, relates to a chemical vapor deposition (CVD) diamond coating drawing die preparation technology, and belongs to metallurgical metals Material plating technology field. Background technique: [0002] Various large-aperture drawing dies are widely used in metal drawing, stranding and pressing of multi-strand wires, thinning of metal pipe walls, pipe wall butt welding, sizing and other purposes. This type of mold is made of cemented carbide in most occasions. In some special occasions (such as aluminum-plastic or other metal and plastic composite pipe production), fluoroplastics are used to reduce the coefficient of friction. Because the wear resistance of cemented carbide is not as good as diamond, and when there is no lubricant, the coefficient of friction with some metals (such as aluminum) is relatively large...

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): B21C3/02C23C16/27
Inventor 张志明沈荷生孙方宏郭松寿金卫国
Owner SHANGHAI JIAO TONG UNIV
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