Polycrystalline diamond composite sheet having continuous gradient transition layer and preparation method thereof

Patent metadata

Field	Value
Publication number	US-12508650-B2
Application number	US-202418604434-A
Country	US
Kind code	B2
Filing date	Mar 13, 2024
Priority date	Sep 25, 2023
Publication date	Dec 30, 2025
Grant date	Dec 30, 2025

Abstract

The disclosure discloses a polycrystalline diamond composite sheet having a continuous gradient transition layer and a 3D printing preparation method thereof. The polycrystalline diamond composite sheet consists of a polycrystalline diamond layer, a continuous gradient transition layer, and a cemented carbide substrate from top to bottom, in which the continuous gradient transition layer consists of diamond and cemented carbide. Along a direction from the cemented carbide substrate to the polycrystalline diamond layer, a content of the cemented carbide in the continuous gradient transition layer decreases from 100% to 0, and a content of the diamond increases from 0 to 100%. By designing and combining the continuous gradient transition layer with 3D printing technology, the disclosure realizes a continuous change in the two materials of diamond and cemented carbide, thereby eliminating the sudden change interface of the materials inside the diamond composite sheet.

First claim

What is claimed is:

1 . A preparation method of a polycrystalline diamond composite sheet having a continuous gradient transition layer, comprising:
mixing, granulating, and drawing sequentially a diamond micropowder and a binder A to obtain a diamond polymer composite filament material, wherein a particle size of the diamond micropowder is 1 to 100 μm; mixing, granulating, and drawing sequentially a WC powder, a Co powder, and a binder B to obtain a cemented carbide polymer composite filament material; putting the diamond polymer composite filament material and the cemented carbide polymer composite filament material into two feed inlets of a 3D printer respectively; controlling a feeding speed of the diamond polymer composite filament material and a feeding speed of the cemented carbide polymer composite filament material through a feeding system according to a model of the polycrystalline diamond composite sheet so that the diamond polymer composite filament material and the cemented carbide polymer composite filament material enter a mixing chamber individually or in different proportions; obtaining a polycrystalline diamond composite sheet green body after being extruded through a nozzle to perform deposition printing; and performing degreasing and synthesizing under a temperature of 1200° C. to 1800° C. and a pressure of 4 to 8 GPa on the polycrystalline diamond composite sheet green body to obtain the polycrystalline diamond composite sheet with a gradient structure, wherein the polycrystalline diamond composite sheet consists of a polycrystalline diamond layer, the continuous gradient transition layer, and a cemented carbide substrate from top to bottom, wherein the continuous gradient transition layer consists of diamond and cemented carbide, a content of the cemented carbide in the continuous gradient transition layer decreases from 100% to 0, and a content of the diamond increases from 0 to 100%, along a direction from the cemented carbide substrate to the polycrystalline diamond layer, wherein a mass ratio of the diamond micropowder and the binder A is 2:1 to 20:1; a composition of the binder A is, in terms of a mass percentage, as follows: 20 to 65% of ethylene-vinyl acetate copolymer, 5 to 35% of polystyrene, 5 to 35% of styrene-butadiene block copolymer, 3 to 10% of dodecyltrimethylammonium chloride, and 1 to 5% of oleic acid; and a diameter of the diamond polymer composite filament material is 1.65 to 1.85 mm.

2 . The preparation method of the polycrystalline diamond composite sheet having the continuous gradient transition layer as claimed in claim 1 , wherein
a mass ratio of a sum of masses of the WC powder and the Co powder to the binder B is 2:1 to 20:1; a composition of the binder B is, in terms of a mass percentage, as follows: 30 to 75% of styrene-butadiene block copolymer, 5 to 35% of polyurethane, 5 to 10% of polyvinyl butyral, 3 to 6% of acrylonitrile-butadiene-styrene copolymer, 3 to 6% of trimellitate, and 1 to 5% of stearic acid; a diameter of the cemented carbide polymer composite filament material is 1.65 to 1.85 mm.

3 . The preparation method of the polycrystalline diamond composite sheet having the continuous gradient transition layer as claimed in claim 1 , comprising:
setting a thickness end point of the cemented carbide substrate as a gradient starting point and setting a thickness end point of the continuous gradient transition layer as a gradient end point according to the model of the polycrystalline diamond composite sheet; controlling the feeding system first so that only the cemented carbide polymer composite filament material enters the mixing chamber, when reaching the gradient starting point, a proportion of the cemented carbide polymer composite filament material entering the mixing chamber decreases uniformly, and a proportion of the diamond polymer composite filament material entering the mixing chamber increases uniformly, according to a thickness of the continuous gradient transition layer; and after the gradient end point is reached, only the diamond polymer composite filament material enters the mixing chamber.

4 . The preparation method of the polycrystalline diamond composite sheet having the continuous gradient transition layer as claimed in claim 3 , wherein during the deposition printing, a position of the gradient starting point is 4 to 13 mm from a bottom of the cemented carbide substrate, a position of the gradient end point is 4.1 to 16 mm from the bottom of the cemented carbide substrate, a printing layer thickness is 0.05 to 0.3 mm, and a printing speed is 10 to 100 mm/s.

5 . The preparation method of the polycrystalline diamond composite sheet having the continuous gradient transition layer as claimed in claim 1 , wherein the degreasing is performed under a vacuum condition, and a vacuum degree is 2.0×10 −2 Pa to 8.0×10 −4 Pa; and a temperature rising process is as the following: first, raising a temperature from a room temperature to 80° C. to 100° C. at 5 to 15° C./min and maintaining for 0.5 to 1 hour; next, raising temperature to 180° C. to 230° C. at 3 to 10° C./min and maintaining for 1 to 2.5 hours; then, raising temperature to 300° C. to 330° C. at 1 to 5° C./min and maintaining for 0.5 to 1.5 hour; and then, raising temperature to 400° C. to 430° C. at 1 to 5° C./min and maintaining for 0.5 to 1.5 hour; and finally, raising temperature to 550° C. to 620° C. at 2 to 6° C./min and maintaining for 0.5 to 1 hour, and then finally cooling with a furnace.

6 . The preparation method of the polycrystalline diamond composite sheet having the continuous gradient transition layer as claimed in claim 1 , wherein during the synthesizing, a temperature and pressure maintaining time is 100 s to 900 s.

Assignees

• Univ Central South
• Sf Diamond Co Ltd

Inventors

• Zhang Shaohe
• Kong Xiangwang
• Zhao Dongpeng
• Li Yulu
• Rong Linglong
• Zhang Haoyang
• Fang Qingyuan
• Gao Hua
• Li Jincheng
• Wu Jingjing
• Shao Mengyao
• Geng Changjian

Classifications

• C04B35/56

  based on carbides {or oxycarbides (containing free metal binder C22C29/00)} · CPC title

• C04B2235/427

  Diamond · CPC title

• C04B35/52

  based on carbon, e.g. graphite · CPC title

• C04B2235/3847

  Tungsten carbides · CPC title

• C04B35/645

  Pressure sintering · CPC title