JPH01183304A - Tip for cutting covering - Google Patents

Abstract

PURPOSE:To improve fixation and stability for a fitting seat to prevent generation of chatter or vibration and to prevent lowering of the service life and the roughness of a finished face for the tip in the caption by forming the seat of the tip for cutting a covering flatter than the surface of a covering film and the roughness of the surface good. CONSTITUTION:A tip 10 is made by forming a covering film consisting of carbide, nitride, oxide of the metal of 4a, 5a, 6a groups in the element periodic table and these compounds, one kind or more than two kinds in Al2O3, ZrO2 on the surface of a square plate like cemented carbide made tip base material 12. Top and bottom surfaces are polished at about 20-100mum by a surface grinder, etc., the exposed portion of the tip base material 12 by removing the covering film 13 is a seating surface 14, a sectional circular tip breaker 16 is formed annularly on an outer circumference and a cutting edge is formed on the ridgeline portion of the side 17. The seating surface 14 is formed at 0.1-3mu of roughness, 0.2-0.4a of flatness and +0.02 of parallel so that the stability for the fitting seat surface of a tip holder becomes better.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a coated cutting tip with excellent fracture resistance and wear resistance.

``Prior Art'' Conventionally, as a coated cutting tip, as shown in FIGS. 5 and 6, on the surface of a tip base material l made of cemented carbide,
Carbides, nitrides, oxides of metals of group 4 as S as 6 a of the periodic table of elements, and their compounds, AhO
A coating film 2 made of one or more of s, ZrO* and coated by a CVD%PVD method is available for use.

``Problem to be solved by the invention'' By the way, in the above-mentioned coated cutting tip,
Due to the unevenness of the film thickness of the coating film 2 formed on the surface and the roughness of the surface of the coating l1i2, the flatness, surface roughness, parallelism, etc. of the seating surface 3.3 are different from those of the polished normal It is inferior to a hard metal tip, and as a result, the fixation of the tip holder to the mounting seat surface and stability are poor, and as a result, chattering vibration occurs while cutting the workpiece, and the cutting edge 4. There was a disadvantage that chipping and abrasion were likely to occur, shortening the service life and making the machine unstable, and that the roughness of the finished surface of the workpiece material was reduced due to the chatter vibrations mentioned above. .

This invention aims to solve the above-mentioned drawbacks.

"Means for Solving the Problems" The coated cutting tip of the present invention has at least 48 elements in the periodic table on the surface of the tip base material other than the portion that becomes the seating surface.
．． The seated surface is coated with a single layer or multiple layers of a coating film consisting of one or more of carbides, nitrides, oxides of metals of groups 5a and 6a, and compounds thereof, A(bO-1ZrO). It is characterized in that the surface is flatter and has better surface roughness than the surface of the above-mentioned coating film.

"Function" In the coated cutting tip of the present invention, the seating surface is flatter and has better surface roughness than the surface of the coating film, so it can be fixed to the mounting seat surface of the tip holder etc. and is stable. Therefore, chattering and vibration are less likely to occur while cutting the workpiece, and this prevents chipping and wear of the cutting edge, which shortens the service life and reduces the finished surface roughness of the workpiece. can be prevented.

"Example" Examples of the present invention will be described in detail below.

FIGS. 1 and 2 show the cutting tip of the present invention (
This figure shows a first embodiment of a chip (hereinafter referred to as a chip).

The chip IO shown in these figures has a surface portion of a cemented carbide chip base material 12 in the shape of a rectangular plate, and corresponds to 4 of the periodic table of elements.
After forming the coating film 13 made of one or more of carbides, nitrides, oxides, and compounds of metals in Groups a, 5a, and 6a, AQvOs, and ZrO*, the upper and lower surfaces are surface ground. 20~ depending on the board etc.! The coating film 13 in this portion was removed by polishing by 00 μl, and the exposed portion of the chip base material 12 after the coating film 13 was removed was used as a seating surface 14.14.

A chip breaker 16.16 having an arcuate cross section is formed in an annular shape on the outer peripheral side of this seating surface 14.14, and these chip breakers 16.16 and side surfaces (flank surfaces) 17...
Cutting blades 18 are formed at the ridgeline portions.

Further, since the seating surface 14.14 is formed by polishing, its surface roughness is 0.1μ to 3μ, which is the seating surface 3°3 (coated film) of the conventional chip shown in FIGS. 5 and 6. The surface roughness (4 μ to 12 μ) of the surface of No. 2) is superior to that of the seating surface 3.3 (0.20 a to 0.40 a), and the flatness is superior to the flatness of the seating surface 3.3 (0.80 a to 3.2 a). Furthermore, the parallelism is ±0.02 and the parallelism of the seating surface 3.3 (±0.05)
Better.

According to the coated cutting tip with the above configuration, the surface roughness, flatness and parallelism of the seating surface 14.14 are superior to the seating surface 3.3 of the conventional tip, so that the mounting of the tip holder is easy. The fixation to the seat surface and stability are better than before. Therefore, it is possible to prevent chattering vibrations from occurring while cutting the workpiece material, thereby suppressing chipping and wear of the cutting edge caused by chattering vibrations and improving the service life. At the same time, it is possible to improve the finished surface roughness of the workpiece.

Further, in the above-mentioned coated cutting tip 10, the coating film 2, which is coated on the seating surface 3.3 of the conventional chip in which a coating film is formed on the entire surface, is removed by polishing with an existing surface grinder or the like. Therefore, the manufacturing cost is relatively low.

3 and 4 show a second embodiment. In the insert 20 shown in these figures, compared to the insert 10 shown in Figs. 1 and 2, the part that becomes the seating surface is only slightly (20μ shoulder) higher than the cutting edge, making it easier to use with existing surface grinders. Because it is difficult to polish only this part, we use a special grinder to locally grind this part into a circular shape with 20~100
The coating film 13 in this portion is removed by micro-polishing, and the exposed portion of the chip base material 21 with the coating film 13 removed serves as a seating surface 22.22.

The surface roughness, flatness, and parallelism of this seating surface 22.22 are set similarly to those of the seating surface 14.14.

Also in the chip 20 having the above configuration, the same effects as in the chip IO of the first embodiment can be obtained.

In the first and second embodiments described above, the seating surface 14.22 of the chip 10° 20 is the portion that becomes the seating surface 14.22 of the chip base material 12, 21 on which the coating film 13 is formed on the entire surface. Formed by polishing.

However, the seating surface 14 may be polished in advance.
．． The coating film 13 may be formed by applying a photomask or the like to a portion other than the area 22, and then peeling off the photomask or the like.

"Experimental Example" Next, an experimental example will be given to clarify the effects of the present invention.

■Experimental Example 1: Three types of chips according to the first embodiment of this invention were prepared, and these chips were used to perform continuous cutting and interrupted cutting on the workpiece, and the results are shown in Table 1. In continuous cutting, it is expressed by the magnitude of flank wear (the magnitude of wear that occurs on the flank face) and the magnitude of crater wear (the magnitude of wear that occurs on the rake face), and in interrupted cutting, it is indicated by the number of teeth on the insert. Indicates the number of usable cutting edges for (8).

■Comparative Example 1: Two types of conventional tips, which have the same shape as the tip in Experimental Example 1 above, but have a coating film formed on the entire surface, were prepared and used as the workpiece material in the same manner as above. Continuous cutting and intermittent cutting were performed using the same method, and the results are shown in Table 1.

In addition, the above experimental example 1 and a comparative example! The cutting conditions are as follows.

Continuous cutting workpiece material: SNCM-8, cutting speed: 25-Ox/wi
ns feed: 0, 35 xj+/rev, cut:
l, 5 mm.

Cutting time: 15s+in.

Chip shape: JIS, SNMG432 interrupted cutting Work material: SNCM-8, Cutting speed: 100 x/mi
n.

Feed: 0, 20 Rm/rev, depth of cut: 1
, OxR.

Cutting time: 5m1n (impact 200 times/5in), depth shape: JIS, SNMG432 Furthermore, ■ Experimental example 2...Five types of chips of the second embodiment of this invention were prepared, and these chips were used. The work material was subjected to continuous cutting and interrupted cutting, and the results are shown in Table 2.

■Comparative Example 2: Two types of conventional tips, which have the same shape as the tip in Experimental Example 2 above, but have a coating film formed on the entire surface, were prepared and used as the workpiece material in the same way as above. Continuous cutting and intermittent cutting were performed using the same method, and the results are shown in Table 2.

The cutting conditions for Experimental Example 2 and Comparative Example 2 are as follows.

Continuous cutting work material: SNCM-8, cutting speed: 180 g+/s
in.

Feed: 0, 4 mz/rev, depth of cut: 1.5i
+i.

Cutting time: 15m1n.

Chip shape: JIS, 5NP432 Intermittent cutting Work material: SNCM-8, Cutting speed: l 00 x/l
l1in, Feed: 0, 25xx/rev, Cut: 3xm.

Cutting time: 5m1n (impact 200 times/lll1n), Chip shape: JIS, 5NP432 or less Margin As is clear from Tables 1 and 2, the coated cutting tip of the present invention is superior to conventional tips. In comparison, it can be seen that the wear resistance and chipping resistance are excellent.

"Effects of the Invention" As explained above, according to the coated cutting tip of the present invention, the surface roughness and flatness of the seating surface are superior to the surface of the coating film, so that Improves fixation and stability compared to conventional methods.

Therefore, it is possible to prevent chattering vibrations from occurring while cutting the workpiece material, thereby suppressing chipping and wear of the cutting edge caused by chattering vibrations and improving the service life. At the same time, it is possible to improve the finished surface roughness of the workpiece.

[Brief explanation of the drawing]

1 and 2 show a first embodiment of the coated cutting tip of the present invention, and FIG. 1 is a perspective view of the tip;
FIG. 2 is a sectional view of the same, FIGS. 3 and 4 show the second embodiment, FIG. 3 is a perspective view of the chip, FIG. 4 is a sectional view, and FIGS. FIG. 6 shows an example of a conventional chip, FIG. 5 is a perspective view of the chip, and FIG. 6 is a sectional view thereof. 10.20... Chip, 12.21... Chip base material, 13...
Coating film, 14.22... Seating surface.

Claims (1)

[Claims] At least on the surface of the chip base material other than the part that becomes the seating surface, a carbide of a metal of group 4a, 5a, or 6a of the periodic table of elements,
Nitride, oxide and their compounds, Al_2O_3
, ZrO_2, characterized in that the seating surface is flatter and has superior surface roughness than the surface of the coating film. coated cutting tip.