JPH02274405A - Polycrystal diamond tool for cutting - Google Patents

Abstract

PURPOSE:To facilitate work so as to make it possible to manufacture a rotary tool and reinforce its edge point by connecting sintered diamond of 0.05 to 0.2mm thickness to an alloy of cemented carbide or the like and reducing a diamond area when a flank is ground by a diamond glindstone. CONSTITUTION:Polycrystal diamond of 0.2mm or less and 0.05mm or more thickness, which is sintered diamond manufactured by the gas phase synthesizing method or under a condition of super high pressure and high temperature, is connected to cemented carbide or steel. A thin film of Ti or Ti compound and iron group metal or the like adheres to a polycrystal diamond surface connected to the cemented carbide or the steel by silver brazing and palladium brazing or a Ni steel material and the like. A rotary tool of diameter less than 6mm can be also manufactured by setting a wedge angle in the tool edge point to 40 deg. to 75 deg., and a polycrystal diamond tool for cutting excellent in its wear resistance and defect resistance and with a low cost is manufactured, showing performance excellent in non-metal cutting, facilitating edging and easily obtaining also dimensional accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION November 11, 111 The present invention relates to a polycrystalline diamond tool for cutting which has excellent wear resistance and chipping resistance and is inexpensive.

Due to its hardness and high thermal conductivity, diamond is used as cutting tools and wear-resistant tools. However, single-crystal diamond has the disadvantage of inter-wall formation, so in order to suppress this disadvantage, sintered diamond is made by crystallizing diamond tools using ultra-high pressure sintering technology, as described in Japanese Patent Publication No. 52-12126. developed and commercially available.

These sintered diamonds are generally made by bonding a sintered diamond layer with a thickness of 0.5 to 1.0 mm on a cemented carbide base material, and the cemented carbide base material improves the strength of the sintered diamond. It is joined together with diamond particles during ultra-high pressure sintering to enable brazing, and can be used as a tool for cutting non-ferrous metals, a tool for cutting wood and inorganic materials, or a bit for rock drilling. This shows excellent performance.

In addition, in recent years, special public
No. 27753 and Japanese Patent Publication No. 59-27754, research on the vapor phase diamond synthesis method is being enthusiastically carried out. This polycrystalline diamond is a sintered diamond produced under ultra-high pressure. As it does not contain iron group metals as solvents, it has excellent heat resistance, and also shows excellent performance in cutting non-ferrous metals.

Hikari 31" 1 Kaishi λ Utomo 4 Section 1 When using sintered diamond manufactured using conventional ultra-high pressure sintering technology as the cutting edge material of a cutting tool, the surface of the sintered diamond is smoothed by lapping and then cemented carbide is used. Yaf
The sintered diamond and cemented carbide base material that form the flanks of the Il alloy are brazed and machined using a diamond grindstone to sharpen the blade and provide dimensional accuracy. In this case, since the sintered diamond is cut by co-cutting with a diamond grindstone, there are problems with low efficiency and high processing costs. Furthermore, since conventional sintered diamond is made by bonding cemented carbide to sintered diamond of 0.5 m or more, it is difficult to manufacture small-diameter rotary tools such as end mills and reamers. Furthermore, as mentioned above, sintered diamond is bonded to improve its strength, but when used as a cutting tool, it often requires finishing, and the wedge angle of the cutting edge is reduced to increase sharpness (this results in intermittent During cutting, only the cutting edge chimed, indicating that the strength was improved by joining the cemented carbide.

Means for solving the problem The inventors of the present invention have conducted extensive research in order to improve the above-mentioned drawbacks of the sintered diamond tool. As a result, if a sintered diamond with a thickness of 0.2 - 0.05 - 1 or more is bonded to a cemented carbide or steel alloy, the area of the sintered diamond will be reduced when machining the flank surface with a diamond grindstone. In addition to saving time, it is also possible to create small-diameter rotary tools such as end mills and reamers, and since the tool edge is similar to high-strength cemented carbide or steel alloy, the edge can be reinforced in one minute. I discovered something.

That is, the present invention is characterized in that polycrystalline diamond with a thickness of 0.2 mm or less and 0.05 mm or more, preferably 15 m5 or less and 0.08 mm or more, is bonded to cemented carbide or steel. A polycrystalline diamond layer for cutting is provided.

The polycrystalline diamond cutting tool of the present invention is generally manufactured as follows. First, it is manufactured by sintering polycrystalline diamond under ultra-high pressure and high temperature, or by a vapor phase synthesis method such as a microwave CVD method or a filament method. That is,
In the case of the ultra-high pressure sintering method, first 0.05
After cutting a plate with a thickness of ~0.21 mm, Ti and N are applied to the surfaces to be joined by sputtering or ion blating.
After coating with iron group metal such as i, it is joined to the alloy by brazing. In addition, when using a vapor-phase synthetic diamond film as the cutting edge material, Si, M.

etc.), the diamond film grown on the plate is dissolved by acid treatment, and then the surfaces to be joined are coated with Ti and iron group metals in the same manner as above and brazed to the alloy. Sintered diamond cannot be brazed, so when brazing it to a base metal, an F4 film of Ti or a Ti compound is attached to the surface of the sintered diamond to be joined, and then an iron group metal thin film is formed. If oxidation of the material is prevented, brazing becomes possible.

The characteristics of the tool of the present invention can be most utilized in the first case where the sharpness of the tool is required, and in this case,
A wedge angle of 40° to 75° for the tool cutting edge shows good performance. If the wedge angle is less than 45°, the strength of the cutting edge is insufficient and the cutting edge will break, and if it exceeds 75°, the cutting quality will deteriorate, which is undesirable. .

As mentioned above, the second tool is a rotary tool such as a small-diameter end mill or leaf, and the diameter is 6 mm using ordinary sintered diamond.
If the diameter is less than 1111, it is difficult to create a tool. In particular, since the tool of the present invention is made of thin polycrystalline diamond, it is easy to manufacture a small-diameter rotary tool having multiple cutting edges. In the polycrystalline diamond tool of the present invention, the thickness of the polycrystalline diamond serving as the cutting edge is 0.2 to 0.05 m.Generally, when cutting non-ferrous metals etc. with a polycrystalline diamond film shell, the number 14 flank When the wear width is about 0.05 m5, the cutting quality becomes poor and the life of the diamond is reached, so the thickness of the polycrystalline diamond should be at least 0.05 m.
If the thickness of the polycrystalline diamond exceeds 0.2 mm, it will take time to process the cutting edge, and the reinforcement of the cutting edge will be insufficient. Furthermore, it becomes difficult to manufacture small-diameter rotary tools, which is undesirable.

FIG. 1 shows an example of a tool corresponding to the first tool, which is a reamer formed by brazing a vapor-phase synthetic diamond film 11.14 to a cemented carbide base metal 13.15 with a brazing material 12.

α indicates the wedge angle of the tool cutting edge.

Figure 2 shows an example corresponding to the second tool described above, in which the sintered diamond film 1.2.3 is applied to the cemented carbide base 4 by brazing materials 5 and 6.
This is an end mill joined to.

FIG. 3 shows an example of a conventional sintered diamond end mill, in which 7 is sintered diamond, 8 is a cemented carbide base material, 9 is a brazing material, and 11 is a cemented carbide base metal.

The tool of the present invention is particularly suitable as a tool for cutting non-ferrous metals. In particular, polycrystalline diamond cutting tools with a cutting edge wedge angle of 40° to 75° have good sharpness and can be machined with almost no deformation of the workpiece.
Demonstrates excellent performance in machining thin-walled parts such as alloys. In addition, polycrystalline diamond has excellent adhesion resistance with non-ferrous metals, so it is possible to obtain a good machined surface.

Additionally, when cutting non-ferrous metals using the small-diameter rotary tool of the present invention, conventional high-speed steel or cemented carbide end mills have poor wear resistance and welding, whereas the tool of the present invention has no welding and has a long service life. Therefore, a stable and good machined surface can be obtained.

Actual tS Example 1 A sintered diamond with a grain size of 5 μ-, which was sintered using an ultra-high pressure and high temperature device, was cut using wire electrical discharge machining to obtain a 1.6*
An F4 k with a right triangle shape of m x 4 ms and a thickness of 0.12 m5 was prepared, and both sides of the F4 k were wrapped. 0.58 m of Ti was deposited on one side of these thin plates using the sputtering method.
After adhering, 3μl of Ni was deposited and brazed to the cemented carbide base metal as shown in Fig. 2 using silver brazing material, and the cutting edge was ground from the flank surface with a diamond grindstone to obtain a diameter of two teeth. A 3s ■ end mill was manufactured. For comparison, the same sintered diamond with a thickness of 0.7 mm and the same shape as the sintered diamond described above was joined to a cemented carbide base metal with a thickness of Is-, and the top surface was rough-finned. After silver brazing on a cemented carbide base metal as shown in Figure 3, a diamond grindstone was used to sharpen the flank from the flank to produce a single-flute aid mill with a diameter of 8 mm. Eight. It was possible to process the blade in a time of .

With these sintered diamond films and a 3mm diameter carbide end mill! -12r, After machining the end face of the Si alloy for 2 hours at a cutting speed of 50 m for 7 minutes, a feed of 0.03 mm/tooth, a vertical cutting depth of 0.2 mm, and an axial cutting depth of 3.
The flank wear width was measured. As a result, the width of flank wear of the product of the present invention, the comparison sintered diamond core, and the carbide end mold increased by 0.015, 0.017, and 0.15, respectively.

Example 2 Particle size 1OllI was deposited on a Si substrate by microwave plasma CvD method (No. 1) and filament method (No. 2).
1 of diamond was synthesized to a thickness of 0.130 mm.

Next, these synthetic films were acid-treated with aqua regia to remove the Si substrate, leaving only the synthetic diamond film, and cut out into a right-angled isosceles triangle with - sides of 5 - ■.TiCO, Ni- by 8 μ cabinet and subverting method
2 μm of Co was deposited, and as shown in FIG. 1, it was joined to the cemented carbide using a Ni brazing material, and the wedge angle of the cutting edge was machined as shown in Table 1. For comparison, 0.5ml thick sintered diamond (particle size 10μ) No. 3 has a thickness of 2ms.
The chips shown in Table 1 were also prototyped, in which a right isosceles triangle with a side of 5-1 was bonded to a cemented carbide base material and silver brazed to a cemented carbide alloy.

These blades were sharpened by machining the flank face with a diamond grindstone, but the machining time for a polycrystalline diamond tool with a thick film of 0.131 carbonate was the same as the machining time for a sintered diamond tool with a thickness of 0.5-fat. It was 18 to -8. One tip of these tools was attached to a 4100-ken cutter with a rake face settable to 18 degrees, and the cutting speed was 500 m for 7 minutes.
Al18 with cutting depth 0.5s+m and feed rate 0.1 liter/blade
After cutting the ZSi alloy for 60 minutes, flank wear width and work surface roughness were measured. The results are shown in Table 1.

Table 1 A No. 1 80° 4.5
um 0.031B No, 1
75@3.1 μm 0.02
5CNo, 2 65” 3.0 #
@0.028D No, 2 60
@2.8 μII O,02
6ENo, 1 50° 2-5 tt-0,0
27D No, 2 40” 3.1 8-fold 0.025F No, 1 35 @ 15 minutes processing and missing #IC No., 3 80 @ 5.2
μII O, 035II No. 3
75" Defected after processing for 20 minutes Example 3 The sintered diamond produced in Example 1 was 0.5X 3
X O, 2 ■■ was made by cutting with a wire electrical discharge machine, the lower surface of E was lapped, and then acid treated with aqua regia.
The Til# and Ni3II layers were deposited by the sputtering method. This surface was bonded to a platinum cemented carbide with palladium brazing and sharpened with a diamond grindstone to produce a four-blade reamer with a diameter of 31 mm. Using this tool, cut Al-18ZSi at a speed of 80 m/min and feed.
Reamed with 0.11/blade. For comparison, cemented carbide glue was also tested, and the tool of the present invention had a lifespan 30 times longer than that of the comparative material.

As explained above, the polycrystalline diamond cutting wheel of the present invention exhibits excellent performance in the field of cutting non-ferrous metals, and the blade is easy to process and provides dimensional accuracy as a tool. Since it is easy to use, it is effective when used in such fields.

[Brief explanation of drawings]

FIGS. 1(a) and (c) are a side view and a front view showing a tip which is an embodiment of the polycrystalline diamond tool for cutting according to the present invention, and FIGS. 2(a) and (b) are FIG. 3 is a front view and a side view showing an end mill that is another embodiment of a polycrystalline diamond cutting tool according to the present invention, and FIGS. 3(a) and 3(b) are a front view and a side view of a conventional sintered diamond end mill. be. Figure 1 (b) /

Claims (6)

[Claims] (1) A polycrystalline diamond tool for cutting, characterized in that polycrystalline diamond with a thickness of 0.2 mm or less and 0.05 mm or more is bonded to cemented carbide or steel. (2) The polycrystalline diamond cutting tool according to claim 1, wherein the polycrystalline diamond is sintered diamond produced under ultra-high pressure and high temperature. (3) The polycrystalline diamond cutting tool according to claim 1, wherein the polycrystalline diamond is sintered diamond produced by a vapor phase synthesis method. (4) A thin film of Ti or a Ti compound and an iron group metal is attached to the polycrystalline diamond surface bonded to the cemented carbide or steel, and the surface and the cemented carbide surface are bonded with silver solder, palladium solder, or Ni steel material to harden the polycrystalline diamond. The polycrystalline diamond tool for cutting according to claim 2) or 3), characterized in that it is joined to an alloy or steel. (5) The polycrystalline diamond tool for cutting according to claim 4, wherein the wedge angle of the cutting edge of the tool is 40° to 75°. (6) The polycrystalline diamond cutting tool according to claim 4, which is a rotating tool having a diameter of less than 6 mm.