JPH10277949A - Method for grinding work piece in corrosive environment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the corrosion resistance by forming the diamond grinding molded body of the diamond polycrystalline lump having a second phases containing chromium and nickel, and setting the diamond content in the molded body to be not less than the prescribed value. SOLUTION: A diamond grinding molded body includes a second phase of chromium and nickel. A volumetric ratio of chromium metal and nickel metal is 10:90-25:75. In the second phase, chromium and nickel are present in the metal mode, the carbide mode and/or the intermetallic compound mode. A cutting point or a cutting edge provided on the molded body is advanced to a work piece through the grinding effect to perform the grinding work including the cutting, drilling and grinding. The diamond grinding molded body can thus demonstrate the excellent corrosion resistance under the environment where the binder and/or the corrosive cleaning chemical is present.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to grinding (or polishing).
Method, especially grinding (or polishing) in a corrosive environment
It is about the method.

[0002]

2. Description of the Related Art Abrasive compacts (consolidated compacts) are well known in the art and are widely used industrially for grinding various workpieces. Said compact is, in effect, 70 parts by volume of the compact.
%, Preferably 80-90%, of abrasive particles which are combined into hard polycrystalline agglomerates. The abrasive particles are diamond or cubic boron nitride.

[0003] The abrasive compact may be used as such,
It may be used by bonding to an appropriate substrate. Usually, the substrate is made of cemented carbide.

[0004] Diamond abrasive compacts are used in a wide range of grinding operations. These compacts can be made using a second phase, or binding matrix, which typically contains a solvent / catalyst suitable for synthesizing diamond. 1
One such shaped body is described in EP-0 198 653. The feature of the compact has a second phase or binding matrix comprising chromium and a second metal selected from the group consisting of nickel, iron and cobalt. The chromium is present in a metal form, chromium carbide and / or an intermetallic compound containing a second metal. The second metal is present in a metal form and / or in the form of an intermetallic compound as described above. In particular, the abrasive compact is useful for a dressing tool or a surface processing drill bit (blade). The abrasive compact is worn out,
Not supported by cemented carbide substrates.

[0005]

[0003] Diamond abrasive compacts are used, for example, in the grinding, eg, cutting of wood products. The hardness and wear resistance of the diamond compact
This is a very useful property in this application. Wood or wood products contain resins and all kinds of organic binders, which remain on the diamond pedestal and must be cleaned with a corrosive cleaning agent, which removes the diamond polished compacts by EDM (electric discharge machining). ), The cobalt binder is leached before the sharpening treatment. Loss of cobalt binder leads to undercut when the cutting edge is resharpened with EDM. This also means that the cutting edge is chipped.

[0006]

According to the present invention, the steps of grinding a workpiece in a corrosive environment include providing a diamond polished compact having a cutting edge or point, comprising: Providing a material, contacting a cutting edge or point of the diamond polished compact with a workpiece, and advancing the cutting edge or point relative to the workpiece in a grinding manner. .

The diamond-polished compact used in the present invention is a polycrystalline diamond mass having a second phase having chromium and nickel, wherein the diamond content of the compact occupies at least 70% of the compact volume. Preferably, said second phase is comprised of chromium and nickel, with only minor amounts of other components. Such diamond compacts have particularly good corrosion resistance in environments where binders and / or corrosive cleaning chemicals are present.

In the method of the present invention, a cutting point or a cutting edge (or a cutting edge) provided on a molded body is advanced with respect to a workpiece with a grinding action. As used herein, the term "grinding" means cutting (or cutting), drilling, polishing or any such grinding operation. Such work can take various forms as is well known in the art,
For example, it can take the form of rotation of the cutting edge or point, reciprocation of the cutting edge or point or the like. Of course, the grinding action is also achieved by keeping the cutting edge or point stationary and moving the workpiece.

In accordance with one aspect of the present invention, there is provided a use as a method for grinding a workpiece in a corrosive environment of a diamond polished compact as described above.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION

DETAILED DESCRIPTION OF THE INVENTION The diamond compact of the present invention is characterized by a second phase containing chromium and nickel. The quantitative ratio of chromium to nickel metal is typically 10:90
２５25: 75. In the second phase, both chromium and nickel will be present in metal form, carbide form and / or in the form of intermetallic compounds of chromium and nickel.

It has been found that the diamond polished compact exhibits excellent corrosion resistance in the presence of binders and / or corrosive cleaning chemicals.

The diamond polished compact can be bonded to a sintered carbide substrate or a metal layer substrate such as molybdenum, tantalum or tungsten.

Thus, the present invention has particular application in the grinding of products containing wood. Examples of wood products are soft or hard natural wood, laminated and laminated chipboard and fiberboard (this includes wood chips or fibers bonded by binders), hardboards that are compressed fibers and sawdust, and It is plywood. The wood product may be plastic or other coated. Some of these wood products may include resins and organic binders. Even in the presence of corrosive cleaning chemicals and / or binders, no significant undercuts occur at the cutting edges or points of the diamond abrasive compacts described above, and thus, much less chipping occurs. Has been found to be. The grinding operation can take the form of sawing, milling or profiling. The tools used for such applications are generally multi-tip rotating tools such as circular saws, profile cutters, end mills, milling cutters and routers.

Next, an example of a method for producing a diamond polished compact containing the nickel / chromium second phase will be described. A mass of diamond particles (16.0 g) was placed in a tantalum cup. Nickel / chromium alloy disc (2.6
g) was placed on this diamond mass. The quantitative ratio of nickel to chromium was 80:20. Nickel / chromium was 14% by volume of the filled tantalum cup.

[0015] The filled cup is placed in the reaction zone of a conventional high temperature / high pressure instrument, at a temperature of 1500 ° C and at 5.
Subjected to a pressure of 5 GPa, these conditions were maintained for 10 minutes. A disk-shaped abrasive compact body was recovered from the reaction zone, the body comprising a second phase containing chromium and nickel as metal and in various bonding forms, this being a diamond mass.
It consisted of aggregates of polycrystalline diamond particles uniformly distributed throughout.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Robert Fries South Africa Johannesburg, Saxonwold, Ristantold Road 11, The Cottage (72) Inventor Jurgen Dietrich Eckert South Africa Johannesburg, Bella Rio, San Juan Avenue 229

Claims (8)

[Claims] 1. A diamond polished compact having a cutting edge or a cutting point, said compact having a second phase comprising chromium and nickel, wherein the diamond content is at least 70% of the volume of the compact. Providing a compact that is a polycrystalline diamond mass; providing a workpiece; contacting a cutting edge or point of the diamond polished compact with the workpiece; and providing the cutting edge or Advancing the cutting point with respect to the workpiece in the form of grinding in a corrosive environment. 2. The method according to claim 1, wherein the second phase of the diamond abrasive compact comprises chromium and nickel. 3. The quantitative ratio of chromium to nickel is 10:
3. A method according to claim 1 or claim 2, wherein the method is in the range 90-25: 75. 4. The method according to claim 1, wherein the workpiece is a product containing wood. 5. The method according to claim 4, wherein the wood product is a wood product selected from natural wood, laminated and non-laminated chipboard and fiberboard, hardboard and plywood. 6. The method according to claim 4, wherein the wood product has a plastic or other coating applied thereto. 7. The method according to claim 4, wherein the wood product comprises a resin or an organic binder. 8. The grinding step includes cutting, drilling, and forming a groove (ro
8. The method according to claim 1, wherein the method is selected from the group consisting of utling) and polishing.