JPH08336704A - Diamond coated milling chip - Google Patents

Abstract

PURPOSE: To improve wearing resistance and loss resistance by forming a connection part between a main cutter edge and a chamfered corner cutter edge and a connection part between the chamfered corner cutter edge and a cleaning cutter edge so as to be respectively curved, providing round honing in the connection parts of these and coating the cutter tips with diamond films. CONSTITUTION: Parts 4 and 5 for connecting a main cutter edge 1 and a chamfered corner cutter edge 2, and the chamfered corner cutter edge 2 and a cleaning cutter edge 3 are respective formed to have curved shapes, and after round honing or chamfer honing is provided from the main cutter 1 to the cutting edge 6 of the chamfered corner 2, the cutter tips are coated with diamond films. In this case, the curved shapes between the cutters 1 and 2 and between the cutter 2 and the cleaning cutter 3 are preferably formed to have curvature radiuses of 0.2 to 0.8mm, and for work done from the main cutter 1 to the cutter edge 6, a vertical distance between a cleaned surface 7 and the upper end part of a cleared surface 8 is set to a range of 0.01 to 0.04mm.

Description

Detailed Description of the Invention

[0001]

This invention relates to wear resistance, fracture resistance,
The present invention relates to a diamond-coated milling chip having excellent welding resistance.

[0002]

2. Description of the Related Art Diamonds for milling chips having a diamond coating on the cutting edge include sintered diamonds and natural diamonds obtained by sintering diamond grains synthesized using ultrahigh pressure and high temperature using a binder. Was used. On the other hand, a diamond vapor phase synthesis (CVD) technology has been developed that decomposes hydrocarbons and synthesizes diamond on the surface of the chip, and the cost is low, and it is possible to cover the shape of the chip and to freely cover it. It is attracting attention because of its high degree. Regarding the vapor phase synthesis method of diamond film, hot filament method, microwave plasma CVD method, DC plasma CVD method
Method, high frequency plasma CDV method, combustion flame method, etc. have been devised.

[0003]

Since diamond tools have excellent wear resistance and welding resistance, they are said to be the most suitable tools for cutting aluminum alloys. Therefore, when the inventors coated the diamond film on the surface of the high rake cemented carbide chip which was usually used in the milling of aluminum die cast (ADC12) by the vapor phase method and performed the cutting, it showed excellent wear resistance at the early stage of cutting. Although the welding resistance was obtained, the finished surface deteriorated rapidly in the latter stage, and finally the life was about the same as that of the cemented carbide tip. The cause was investigated, and before the diamond film coated on the chip was abraded and the cemented carbide substrate appeared, the diamond film's microdefects, peeling, and cemented carbide substrate defects progressed, and the diamond film coating effect was no longer utilized. It became clear.

This process will be described in detail. That is, with the progress of the cutting process of the aluminum alloy, first, the main cutting edge and the chamfering corner cutting edge, and the chamfering corner cutting edge and the flat edge are connected to the diamond film, where minute defects and peeling of the diamond film occur. The peeling area progresses to the chamfering corner cutting edge, the main cutting edge, and the flat cutting edge. And inclusions (eg Al ₂ O ₃ ) in the aluminum alloy
If the above is included, the above phenomenon develops rapidly. As the peeling of the diamond coating progresses, the chip base material also becomes defective. Therefore, in practical use, there is a strong demand for the development of a diamond-coated milling chip that is unlikely to cause such minute defects in the diamond coating, peeling or damage to the substrate itself and can be repeatedly used for a long time.

[0005]

The present inventors have completed the present invention as a result of research for the purpose of developing a diamond-coated milling chip that can meet demands. That is, in the present invention, the main cutting edge ridge and the chamfering corner cutting edge ridge, and the connecting portion of each of the chamfering corner cutting edge ridge and the smooth edge ridge is curved, and the main cutting edge ridge, the chamfering corner cutting edge ridge and both edges Round honing or chamfer honing is applied to the connection part of
The present invention relates to a diamond-coated milling tip whose cutting edge is coated with a diamond film.

The inventors of the present invention have made extensive studies on the above-mentioned conventional diamond-coated chip delamination phenomenon of the diamond coating and the process of chipping of the chip base material, and as a result, it has been found that the base material of a specific shape is coated with diamond. The present invention was completed after confirming that the purpose was achieved. The processed chip of the present invention will be described with reference to the drawings.

As shown in FIG. 1, the main cutting edge 1 and the chamfering corner cutting edge 2 and the portions 4 and 5 connecting the respective ridges of the chamfering corner cutting edge 2 and the flat cutting edge 3 have a curved shape, and the main cutting edge 1
From the above, it was revealed that the effect of the diamond coating is maximized by performing the round honing or the chamfer honing on the cutting edge 6 of the chamfering corner 2. Regarding the honing process performed here, FIG. 2 shows the cross-sectional shape of the cutting edge of the round honing, and FIG. 3 shows the cross-sectional shape of the cutting edge of the chamfer honing. In this figure, 9 is a round honing portion, 12 is a chamfer honing portion, 10 and 13 are side views of the rake face, and 11 and 14 are side views of the flank face.

Further optimization of the curved shape and the honing width shows that the curved shape R1 at the point where the main cutting edge and the chamfering corner cutting edge and the chamfering corner cutting edge and the flat cutting edge are connected is shown in FIG. Radius of curvature 0.2
Round honing or chamfer honing applied from the main cutting edge to the cutting edge ridge of the chamfering corner by forming it with a thickness of ~ 0.8 mm is the dimension seen from the flank side in Figs. 2 and 3, in other words, the rake surface after honing. And the vertical distances d1 and d2 from the upper end of the flank are 0.01 to 0.04 mm, and the chamfer honing angle α with respect to the rake face shown in FIG. 3 is 10 to 30 °. It has been revealed that the effect will be exhibited.

With the above cutting edge shape, the radius of curvature R1 is 0.2 m.
When it is smaller than m, the diamond film is likely to be damaged or peeled, and when it is larger than 0.8, the welding resistance is deteriorated. When the honing widths d1 and d2 are smaller than 0.01 mm, the diamond film is damaged. , Peeling and chipping of the cemented carbide tip are likely to occur, and when 0.04 mm or more, the cutting resistance during machining increases and the finished surface roughness deteriorates. Further, the angle α is less than 10 ° by chamfer honing. It was revealed that in this case, the diamond film and the cemented carbide chip were likely to be damaged, and when the angle was more than 30 °, the cutting resistance during processing was increased and the finished surface roughness was deteriorated.

[0010]

The diamond-coated milling chip of the present invention can be repeatedly used for a much longer time than the conventional diamond-coated milling chip.

[0011]

【Example】

<Examples and Comparative Examples> SE is a substrate having various shapes of cutting edges.
Carbide chips, EN1203, K10, diamond coated chips (thickness 8 μm by hot filament CVD method)
Was produced as shown in the table. 50m x 50mm x 300mm aluminum die cast block (ADC12) is used as the work material
The milling evaluation was carried out by cutting the m × 50 mm end face. Cutting was evaluated by how many times the end face of the aluminum die-cast block could be cut by attaching one chip to the face mill. The life of the tip was judged when the surface roughness of the work material reached 6S. The cutting condition is a cut of 0.
5 mm, feed rate 0.05 mm / blade, cutting speed 1000
Dry cutting was performed at m / min. The results of the evaluation conducted under the above conditions are shown in the table.

[0012]

[Table 1]

Experiment No. No. 1 compared to the unprocessed carbide tip of Comparative Example 1 (Comparative Example 1). The number of treatments of the diamond-coated chips of the present invention of 5 to 12 (Examples 1 to 8) was 4.5 to 8.
It is 1 time. In addition, an experiment No. in which a carbide tip was subjected to honing treatment 2 and 3 (Comparative Examples 2 and 3) have a lower cutting frequency than Comparative Example 1. This is because when the honing process is performed on the cemented carbide tip, the sharpness is lowered and the cutting resistance is increased, so that the aluminum is welded to the cutting edge and the finished surface roughness is deteriorated. The diamond-coated milling chip of the present invention does not cause the above-mentioned phenomenon because diamond is chemically stable, aluminum welding is unlikely to occur, abrasion resistance is high, and the blade edge is not easily blunted.

In Experimental Examples 13 and 14 (Comparative Examples 5 and 6), honing was also applied to the flat blade. In this case, the sharpness of the flat blade, which is important for finishing the surface to be cut, is extremely reduced, so that the finishing accuracy is deteriorated and it is apparent that the blade cannot be used. Experiment No. Although 15 to 20 (Examples 9 to 14) are within the scope of the present invention, some requirements are out of the preferable range, and therefore the number of cuttings is slightly less.

[Brief description of drawings]

FIG. 1 is a perspective view of a diamond-coated milling chip of the present invention (for a right-handed case).

FIG. 2 is a view showing a cross section of a cutting edge subjected to round honing.

FIG. 3 is a view showing a cross section of a cutting edge subjected to chamfer honing.

FIG. 4 is a view of the diamond-coated milling chip (for right hand cutting) of the present invention as seen from the rake face.

[Explanation of symbols]

1 Main cutting edge 2 Chamfering corner cutting edge 3 Flat blade 4 Point where main cutting edge and cutting edge of chamfering corner are connected 5 Point where chamfering corner cutting edge and cutting edge are connected 6 Cutting edge with honing 7 Rake face 8 flank face 9 round honing part 10 rake face 11 flank face 12 chamfer honing part 13 rake face 14 flank face 15 main cutting edge d1 rake face of diamond coated milling tip of the present invention with chamfer honing Vertical distance from upper end of flank d2 Vertical distance between rake face and upper end of flank of diamond-coated milling insert of the present invention with round honing R1 Curvature radius of curve at connection point of each cutting edge

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Norimichi Aoki 1 Soga, Shiojiri City, Nagano Prefecture Shiojiri Research Institute, Showa Denko KK

Claims (4)

[Claims] 1. The main cutting edge ridge, the chamfering corner cutting edge ridge, and the chamfering corner cutting edge ridge and the flat edge ridge are connected to each other in a curved shape, and the main cutting edge ridge, the chamfering corner cutting edge ridge, and both edges are connected. A diamond-coated milling tip with round honing or chamfer honing applied to the connection and the cutting edge covered with a diamond film. 2. The diamond-coated milling chip according to claim 1, wherein the radius of curvature of the curved shape of the connecting portion of each cutting edge is in the range of 0.2 to 0.8 mm. 3. The diamond-coated milling tip according to claim 1, wherein the vertical distance between the rake face and the upper end of the flank face after honing is in the range of 0.01 to 0.04 mm. 4. The diamond milling tip according to claim 1, wherein the honing is chamfer honing, and the angle of the chamfer honing with respect to the rake face is in the range of 10 to 30 °.