KR20150122153A - Cvi bonded and coated pcbn to wc tool body - Google Patents

Abstract

A cutting tool (10) and a method of manufacturing a cutting tool are provided. The cutting tool 10 includes a sintered superabrasive tip 12 having a plurality of polycrystalline boron carbide grains, a tool body 14, and an unbraided material 24. [ The non-braze material 24 fills the gaps 15, 16 between the superabrasive tip 12 and the tool body 14. A method of manufacturing a cutting tool includes the steps of providing a superabrasive tip (12); Providing a tool body (14); Filling the gaps (15, 16) between the superabrasive tip (12) and the tool body (14) with the non-braze material (24); And depositing a first coating (22) on the non-braze material (24).

Description

CVI bonded and coated PCBN (CVI BONDED AND COATED PCB TO TOC TOOL BODY)

This application is a continuation-in-part of U.S. Provisional Application, filed on February 28, 2013 entitled " CVI BONDED AND COATED PCB TO TOC TOOL BODY ". 61 / 770,419. ≪ / RTI >

The present invention relates to a cutting tool for metal machining, said cutting tool comprising at least one body comprising polycrystalline cubic boron nitride (PCBN) with or without a back side of a cemented carbide, and a hard and wear resistant refractory (CVI) or chemical vapor deposition (CVD) with a porous or microgranular medium to fill gaps between the PCBN tool tip and the WC tool body, and more particularly, .

Polycrystalline cubic boron nitride (PCBN), polycrystalline diamond and polycrystalline diamond composite materials are commonly used to provide a carbide cutting edge for cutting tools such as cutting tools used in metal machining.

Cutting tools with cutting edges formed of a carbide abrasive such as cubic boron nitride (CBN) based material are manufactured by powder metallurgy techniques and are mainly used for machining of cast iron and hardened steel. Several types of CBN cutting tools are known, and most cutting tools consist of a PCBN tip that is soldered to a cemented carbide insert. Other cutting tools have a PCBN-bearing body that is directly sintered to the back of the cemented alloy thick enough to make the insert, while the further other cutting tools are made of a PCBN-containing body that has no cemented alloy backing.

Applying a sintered PCBN body at temperatures above 1000 ° C may result in undesirable structural changes in the material. In addition, in the case of soldered inserts, the solder joints will be destroyed.

Therefore, it can be seen that there is a need for a cutting tool having a hot junction between the PcBN tool tip and the tool body WC / Co.

In one embodiment, the cutting tool comprises: a sintered superabrasive tip having a plurality of carbide particles; A tool body for holding the super abrasive tip; And a non-braze material filling the gaps between the super abrasive tip and the tool body.

In another embodiment, the method includes providing a sintered superabrasive tip; Providing a tool body; Filling the gap between the superabrasive tip and the tool body with a non-braze material; And depositing a first coating on the non-braze material, wherein the first coating is a deposit coating for bonding the tip, body, and non-braze materials together.

In a further alternative embodiment, the cutting tool comprises: a sintered superabrasive tip having a plurality of carbide particles; A tool body for holding the super abrasive tip; A deposition bond coat between the superabrasive tip and the tool body; And sintered superabrasive tips and high temperature coatings attached to the tool body.

The foregoing summary and the following detailed description of the embodiments will be better understood when read in conjunction with the appended drawings. It is to be understood that the embodiments depicted are not limited to the exact arrangements and arrangements shown.

1 is a perspective view of a super abrasive tip attached to a tool body according to an exemplary embodiment;
2 is an optical image of a cross-sectional view of a superabrasive tip attached to a tool body according to another exemplary embodiment;
3 is a partially enlarged optical image of a cross-sectional view of an ultra abrasive tip attached to a tool body as shown in Fig.
4 is a flowchart showing a method of manufacturing an ultra abrasive tip attached to a tool body according to an exemplary embodiment.

As used herein, the term "cutting tip" relates to a body for grinding or cutting a workpiece produced by manufacturing processes including mixing ultra abrasive particles with a bond.

As used herein, the term "tool body" refers to a rigid body that rigidly holds the cutting tip (s) in place, the cutting tips being utilized in turning, milling, boring, cutting, or drilling applications .

In an exemplary embodiment, the cutting tip may be comprised of ultra abrasive particles attached to a suitable tool body such as a cemented carbide light metal. Exemplary embodiments utilize chemical vapor deposition (CVI) or chemical vapor deposition (CVD) with a porous or microgranular medium to fill gaps between the superabrasive tool tip and the tool body. Deposition by CVI or CVD may bond the porous or fine granular media to one another and to the cutting tip and the tool body. A sequence of high temperature coating or multilayer coatings such as Al ₂ O ₃ may be subsequently coated as part of the same process to provide enhanced abrasion resistance.

More specifically, the porous or fine granular media used may withstand CVI or CVD processes. Alternatively, fine granules such as diamond or cubic boron nitride may be consumed by the process. The sequence of the intrinsic coating or multilayer coatings may be deposited to provide additional abrasion resistance to the cutting tool during machining, which may or may not affect the strength of the already-bonded joint (as opposed to metallic brazing).

1, the cutting tool 10 may include a tool body 14 that includes a sintered superabrasive tip 12 and an aperture 19. The tool body 14 may be made from a number of materials including cobalt cemented tungsten carbide. The tool body 14 may be designed to hold the superabrasive tip 12. The sintered superabrasive tip 12 may have a plurality of carbide grains that may be selected from the group of cubic boron nitride, diamond, diamond composite, and ceramic materials. There may be a gap or seam between the super abrasive tip and the tool body, such as bottom clearance 15 and sidewall clearance 16, for example. The superabrasive tip 12 may or may not have a back support. The rear support portion may be a carbide support portion such as a tungsten carbide support portion.

2, the cutting tool 10 may include an ultra abrasive tip 12 having a tungsten carbide support 20. The superabrasive tip 12 may have polycrystalline cubic boron nitride (PcBN) particles. The cutting tool 10 may further include a tool body 14 for holding the superabrasive tip 12. The non-braze material 24, which may have a melting point of at least 1000 캜, may be deposited to fill the sidewall gap 16 and the bottom gap 15. The non-abrasive material 24 may be at least one of, for example, zeolite, ceramic, cubic boron nitride, and diamond. The cutting tool 10 may further include coatings such as an infiltrant bond coating 22 on the non-braze material 24 between the superabrasive tip and the tool body. The deposition bond coatings 22 may cover the sintered superabrasive tip 12, the back support 20, and the tool body 14. The deposition bond coatings may comprise at least one of Group IVB compounds including, for example, TiN, TiC, and C, N, O, B, such as TiCN, ZrN, ZrC, ZrCN, HfN, HfC, HfCN.

The magnified optical image shown in FIG. 3 shows that coatings 22, such as TiN, may cover all of the cubic boron nitride crystallites 24. The coatings 22 may additionally provide a bond between the non-braze material, such as cBN, diamond or zeolite, the superabrasive tip 20, and the tool body 14.

Since the non-braze material has a melting point of at least 1000 캜, a high temperature resistant coating such as Al ₂ O ₃ (not shown) may be applied to the sintered super abrasive tip 12, the tool body 14, and the sintered super abrasive tip 12 And the tool body 14, as shown in FIG.

Fig. 4 shows an exemplary method 400 of a cutting tool manufacturing process. The process may include providing a superabrasive tip (step 401); Providing a tool body (step 402); Filling the gap between the super abrasive tip and the tool body with the non-braze material (step 403); And depositing a first coating on the non-braze material (step 404).

The sintered superabrasive tip may be attached to the tool body by several methods. The cutting tool may then be placed in a CVD (chemical vapor deposition) reaction vessel, so that the air is removed and replaced by gases containing inert and reactive species. Metallic deposition may use gases including metal carbonyl or metal-acetal-acetonates, such as iron pentacarbonyl. Ceramic deposition precursors may also represent N, C, and O, including compounds that crack at temperatures below < RTI ID = 0.0 > 1000 C. < / RTI > In some exemplary embodiments, the ceramic deposition bulb waters, for example _{TiCl 4, NH 3, CH 4} , AlCl 3, (Me) 3 Al, N 2, CH 3 CN, H 2, CO, CO 2 or a And mixtures thereof. The gases penetrate the gaps, shims, contact slots through diffusion, and are deposited on heated solid surfaces that are gas accessible, either externally or internally in the apparatus. Upon condensation at the surface, the condensed phases react chemically to form a new solid phase as the first coating. The first coating may be a deposition coating for bonding together the superabrasive tip, the tool body, and the non-braze materials. For example, TiCl ₄ + CH ₄ → TiC solid + gaseous 4HCL. These solid phases are adhesively bonded to solid surfaces according to chemical affinity. The quality of the solid phase (crystal completion, density) depends on the affinity and temperature for the solid surface (s) when condensing on solid surfaces. The deposition, condensation, and reaction processes to form the new solid phase continue as long as the temperature is high and reactants are present. Once the holes are filled, a straight-forward coating may then occur on the surfaces of the superabrasive tip and toolholding material.

Gas accessibility is determined by temperature and pressure dependent gas diffusion. The lower pressure allows deeper diffusion of the reaction gases into the shims and gaps in the tool assembly. The gas deposition, reaction, and solidification rates that form the solid should be controlled to prevent premature "plugging" of narrow gaps and shims, thus reducing film contact area and bond strength. This typically requires that the temperature be lowered or that the gas phase partial pressures of the reactants be controlled. Finally, the quality of the formed film, its crystallinity, and the crystal orientation are temperature and time dependent. If the film is formed and quenched too quickly, the film may have inferior qualities and cracks within the film or at the film-tip or film-tool interface.

It is important that the gaseous precursors react to solid surfaces without disruption regardless of the orientation in the reactor. Called " line-of-sight "deposition processes, such as physical vapor deposition (PVD), may not be as effective as gaseous precursors and may not penetrate gaps and shims, The adhesive strength may be considerably reduced.

In addition, nonvisual CVD coatings do not want the tools to be flipped over to be processed multiple times to form a uniform coating. CVD coats all gas accessible surfaces within a furnace cycle.

Gaseous reactants, which may also be considered by CVD, include any gas-solid reactions such as oxidation, hydration, or carbonization. The solid components may first be absorbed into the surfaces, then reacted and crystallized, or formed on the surface and deposited by solid-surface tensile forces prior to reaction and crystallization.

CVD subsequent processing, such as annealing, may be performed to improve the quality of film or film-tip / film-tool adhesion.

One or more steps may be inserted between each of the above-described steps 401-404 without departing from the scope of the present disclosure, or may be substituted for each of the above-described steps.

Although specific embodiments have been referred to, it will be appreciated that other embodiments and modifications may be devised by those skilled in the art without departing from the spirit and scope of the invention. The appended claims are intended to be construed as including all such embodiments and equivalent modifications.

Claims (28)

A sintered superabrasive tip having a plurality of carbide grains;
A tool body for holding the super abrasive tip; And
And a non-brazing material filling the gap between the super abrasive tip and the tool body. The method according to claim 1,
Wherein the carbide grains are selected from the group of cubic boron nitride, diamond, diamond composite, and ceramic materials. The method according to claim 1,
Wherein the non-braze material is at least one of zeolite, cubic boron nitride, diamond, and ceramic. The method according to claim 1,
Further comprising coatings on the non-braze material. The method according to claim 1,
Wherein said non-braze material has a melting point of at least < RTI ID = 0.0 > 1000 C. < / RTI > 5. The method of claim 4,
Wherein said coatings comprise at least one of Group IVB compounds including C, N, O, < RTI ID = 0.0 > B. < / RTI > The method according to claim 1,
Wherein the tool body comprises at least one of tungsten carbide, ceramic, or cermet. 5. The method of claim 4,
Wherein the coatings cover the sintered superabrasive tip and the tool body. Providing an ultra abrasive tip;
Providing a tool body;
Filling the clearance between the super abrasive tip and the tool body with a non-braze material; And
Depositing a first coating on the non-braze material. 10. The method of claim 9,
Further comprising depositing the first coating, wherein the first coating is an infiltrant coating for bonding the superabrasive tip, the tool body, and the non-braze materials together. 11. The method of claim 10,
Wherein said first coatings comprise at least one of Group IVB compounds comprising C, N, O, 10. The method of claim 9,
Further comprising depositing a sequence of second coating or multilayer coatings on the sintered super abrasive tip, the tool body, and the non-braze material. 13. The method of claim 12,
Wherein the second coating or sequence of multilayer coatings comprises at least one layer of a thermosetting oxide coating. 13. The method of claim 12,
Wherein the high temperature resistant oxide coating is an aluminum oxide coating. 12. The method of claim 11,
Further comprising bonding the non-braze material, the sintered super abrasive tip, and the tool body. 10. The method of claim 9,
Wherein the deposition of the first coating is through chemical vapor deposition. 10. The method of claim 9,
Wherein the deposition of the first coating is through chemical vapor deposition. A sintered superabrasive tip having a plurality of carbide particles;
A tool body for holding the super abrasive tip;
A deposition bond coating between the superabrasive tip and the tool body; And
Wherein the sintered superabrasive tip and the thermosetting coatings deposited on the tool body. 19. The method of claim 18,
Further comprising a non-braze material disposed between said superabrasive tip and said tool body. 19. The method of claim 18,
Wherein the high temperature resistant coating is aluminum oxide. 20. The method of claim 19,
Wherein the non-braze material is bonded to the superabrasive tip and the tool body. 19. The method of claim 18,
Wherein the superabrasive tip has cemented carbide particles and the superabrasive particles are selected from the group of cubic boron nitride, diamond, diamond composite, and ceramic materials. 20. The method of claim 19,
Wherein the non-braze material comprises at least one of zeolite, cubic boron nitride, diamond, and a ceramic material. 24. The method of claim 23,
Wherein said non-braze material is bonded by a hot coating (s). 19. The method of claim 18,
Wherein the high temperature coating is selected from at least one of Group IVB compounds including C, N, O, 19. The method of claim 18,
Wherein the sintered super abrasive tip has a back support. 27. The method of claim 26,
Wherein the rear support portion is a carbide support portion. 28. The method of claim 27,
Wherein the carbide support is tungsten carbide.

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