Diamond composite sheet and its manufacturing method

Abstract

The invention provides a polycrystalline diamond clad sheet for drill teeth of a drill bit and a manufacturing method of the polycrystalline diamond clad sheet. The diamond clad sheet is prepared from, by weight, 5-9 parts of large-diameter high-strength diamond micro powder, 1-5 parts of small-diameter low-strength diamond micro powder, and 0-2 parts of sintering aids. The raw materials are assembled with a hard alloy matrix. The sintering pressure is 5000-6000 MPa, the sintering temperature is 1500-1600 DEG C, the sintering time is 30-600 seconds, and the diamond clad sheet is obtained through sintering. Through the design of the diamond micro powder formula, the low-strength fine-grained diamond micro powder can be selectively sacrificed in the synthesis and pressurization processes, and the purpose that high-strength coarse-gained diamond forming a polycrystalline diamond layer framework is protected and is intact is achieved. Crushing of the diamond micro powder is controllable, the diamond volume ratio of a polycrystalline diamond layer can be increased through advanced micro powder proportioning, and accordingly the abrasion resistance, impact resistance and heat resistance of the product are improved comprehensively. The diamond clad sheet can be widely used for manufacturing the diamond clad sheet drill bit drill teeth.

Description

technical field [0001] The invention relates to a diamond-tungsten carbide composite sheet (diamond composite sheet or PDC for short), which belongs to the field of superhard material manufacturing. Especially diamond compact drill bits. Background technique [0002] Diamond-tungsten carbide compact (abbreviated as diamond compact or PDC) is made by assembling the diamond powder mixed with a certain proportion of sintering aids and the cemented carbide substrate, and using a special press at 4-6GPa, 1400-1600℃. Sintered under ultra-high pressure and high temperature conditions. PDC is composed of polycrystalline diamond layer and cemented carbide matrix, which combines the high wear resistance of polycrystalline diamond layer and the good toughness and weldability of cemented carbide matrix. It is widely used in fields such as oil drilling, geological drilling and coal mining. The performance indicators of a good polycrystalline diamond composite sheet mainly include: hig...

AI Technical Summary

Problems solved by technology

[0003] In order to overcome the deficiencies of the existing technology and solve the uncontrollable fracture of the diamond in the pressurization stage of the ultra-high pressure and high temperature sintering process of the diamond powder, resulting in cracks in the diamond particles and the reduction of the coarse-grained diamond in the skeleton, which affects the wear resistance of the product And impact resistance; the cracking of diamond also changed the original design formula, the diamond particle size became smaller, resulting in an increase in the content of sintering aids in the polycrystalline diamond layer, and poor heat resistance of the product.

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