Polycrystalline diamond compact, manufacturing method thereof, PDC bearing assembly and cutting tool

Abstract

The invention provides a polycrystalline diamond compact, a manufacturing method thereof, a PDC bearing assembly and a cutting tool. The polycrystalline diamond compact comprises an alloy matrix layer and a diamond layer, wherein the diamond layer is combined with the alloy matrix layer through high-temperature sintering; the polycrystalline diamond compact further comprises an alloy steel layer; and the diamond layer, the alloy matrix layer and the alloy steel layer are sequentially arranged in the first direction, and the alloy matrix layer and the alloy steel layer are combined with each other through diffusion welding. The manufacturing method comprises the steps that powder raw materials of the diamond layer, the alloy matrix layer and the alloy steel layer are all placed into high-temperature and high-pressure equipment for synthesis. The PDC bearing assembly comprises the polycrystalline diamond compact. The cutting tool comprises the polycrystalline diamond compact. The alloy matrix layer and the alloy steel layer are combined through diffusion welding, the shear strength of a welding seam of the two material layers is effectively improved, and the overall strength of the polycrystalline diamond compact of a three-layer structure is improved. In addition, secondary welding is not needed, the production efficiency is improved, and the diamond layer is prevented from being damaged by secondary high temperature.

Description

technical field [0001] The invention relates to the technical field of superhard composite materials, in particular to a polycrystalline diamond composite sheet, a manufacturing method thereof, a PDC bearing assembly and a cutting tool. Background technique [0002] The diamond composite sheet is sintered together with diamond powder and cemented carbide matrix (alloy matrix layer) under high temperature and high pressure, and the diamond powder is sintered into a polycrystalline diamond layer, so that the composite sheet has the ultra-high hardness and wear resistance of diamond. Diamond compacts can be used in various working environments, such as diamond compacts can be used on PDC drill bits and PDC bearings. [0003] Taking the PDC bearing as an example, the diamond compact needs to be installed and welded to the support ring of the PDC bearing. There is an installation position on the support ring, and after the diamond composite sheet is placed in the installation po...

AI Technical Summary

Problems solved by technology

[0005] The problem existing in the existing polycrystalline diamond compact is that if the cemented carbide substrate and the support ring are welded by brazing, the weld strength between the cemented carbide substrate and the support ring is low, and the impact resistance is poor; The polycrystalline diamond composite sheet is provided with a connecting layer. Due to the brazing and welding between the connecting layer and the cemented carbide substrate, the shear strength is low, and the weld between the connecting layer and the cemented carbide substrate is prone to fracture.

In addition, during the secondary high-temperature welding of the connecting layer and the cemented carbide substrate, there is a possibility of damaging the diamond layer, and the production efficiency is reduced

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