JPS63300804A - Throw away tip - Google Patents

Abstract

PURPOSE:To promote the cost down and to eliminate the necessity for repolishing by providing a recessed part in the upper surface corner of a polygonal bed metal consisting of cemented carbides or the like and interposing an active metal, having chemical affinity with diamond, between the diamond and a brazing material. CONSTITUTION:A single crystal diamond cutting edge 3 is chemically connected to a recessed part 2 in a polygonal bed metal 1. This connection is performed by any of the active metals Ti, Ta, Nb, Fe, Hf, having chemical affinity with diamond, or by a Cu-Ag system brazing material under the interposition of their alloy. And the inactive atmosphere of vacuum and argon or the like is required for connecting the active metal to the diamond, but work by the Cu-Ag system brazing material can be performed in the air. While it is preferable to provide at Au layer between the active metal and the Cu-Ag system brazing material and to prevent oxidation. By the above described, promoting the cost down, the necessity for labor of repolishing in cutting is eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention aims to provide a throw-away tip for use in precision cutting of non-ferrous metals and non-metals such as aluminum, copper alloys, and plastics.

[Prior Art] This type of seed chip is made of various materials such as cemented carbide and ceramic for convenience in manufacturing and use. However, due to its ultra-hardness and high price, diamond has not become popular, and only some tools with cutting edges made of sintered diamond are used.

[Problems to be solved by the invention] Compared to sintered diamond and cemented carbide, single-crystal diamond cutting edges are less likely to weld the workpiece and are extremely sharp.
Extremely good at precision cutting.

However, because it has excellent properties and is mainly natural, its price is higher than sintered diamond, and because it is fixed by force/mechanism or powder metallurgy, it is not used in indexable types.

[Means to solve the problem] Regarding the price, it is possible to obtain indexable inserts that are sufficient for industrial production by researching and improving the size and shape of a practical diamond cutting blade and the brazing method for fixing. done.

Diamonds should be less than 1/10 carat, preferably! /20
ct or less cutting edge into the recess of the highly rigid cemented carbide base
Obtained by strong bonding using uAg-based brazing material.

[Function] Made of four parts of highly rigid alloy! Although the diamond cutting blade is as small as 1/20ct, it is superior in accuracy, performance, and durability compared to cutting tools with large diamond cutting blades that are fixed to the shank by conventional caulking or powder metallurgy. There was no place to take as a course. In addition, since the price is reduced, sufficient economy can be achieved as a throw away.

[Example] Figure 1A shows a front view and a side view of the chip of the present invention.
2 is a polygonal board base made of cemented carbide, 2 is a recess provided at the corner of the top surface, 3 is a cutting blade made of single crystal diamond, and FIG. 2 is a cutting blade showing four types of blade shapes of cutting blade 3. It is an enlarged view from the top. The cutting blade 3 is chemically bonded to the recess 2, and the scooping surface is finished by brazing so as to be formed by 100 or 0 faces of single crystal diamond. The finished size is approximately 1/20 ct.

Chemical bonding is performed using T++ Tap Nb+ Fe+ NI, an active metal that has chemical affinity with diamond.
+ Cu in the presence of either Hr or its alloy
-A This is done using a g-based brazing filler metal.

Bonding of an active metal and diamond requires a vacuum or an atmosphere rich in inert gas such as argon, but work using an N Cu-Ag brazing filler metal can be performed in air.

In addition, there is AuJ between the active metal and the Cu-Ag brazing filler metal.
It is preferable to provide ilffi to prevent oxidation.

A necessary metal coating may be applied prior to the Cu-Ag brazing filler metal.

The indexable insert shown in the drawing was attached to a special holder manufactured to fit the indexable insert, and a cutting test was conducted. The results are shown in the table below.

From the machined surface roughness record, feed amount o, os, o, os fin/r
The waveform of the surface roughness when using e-ma is Standard II+ correct.

This shows how sharp these bites are.

[Effects of the invention] We have realized an indexable cutting tool with a single crystal diamond cutting edge, which had not been economically or technically expected and was not put to practical use. By making it indexable, you can obtain the necessary cutting tools at a low price and in a short delivery time, and there is no need for regrinding or other trouble during cutting.

[Brief explanation of drawings]

1A and 1B are a front view and a side view of a tip according to an embodiment of the present invention, and FIG. 2 is a partially enlarged explanation showing the shape of a cutting edge of an embodiment of the present invention. 1... Polygonal plate base metal, 2... Concave portion, 3... Single crystal diamond cutting blade.

Claims (4)

[Claims] (1) A polygonal alloy made of cemented carbide or other rigid material is fixed by soldering to a recess provided at the corner of the upper surface of the alloy, with the scooping surface positioned on the 100 or 110 plane of a single crystal diamond. Throw-away insert featuring a sharp diamond cutting edge. (2) The tip according to claim 1, wherein the diamond cutting edge is formed to be 1/10 ct or less. (3) At least during brazing, one or more of active metals Ti, Ta, Nb, Hf, Fe, and Ni having chemical affinity with diamond are interposed between the diamond and the brazing material. A chip according to claim 1 or 2. (4) The chip according to claim 3, wherein the brazing material is Cu-Ag type, and the active metal and the brazing material are brazed with Au interposed between them.