JPS605666B2 - Ultra-high pressure sintered material for cutting tools - Google Patents

Description

Detailed Description of the Invention The present invention has excellent wear resistance and toughness, and also has excellent welding resistance and thermal shock resistance. This invention relates to an ultra-high pressure bonded material suitable for use as a cutting tool in machining.

In recent years, cubic crystal nitride (hereinafter referred to as C
There is a tendency to use ultra-high pressure sintered materials (abbreviated as BN) as cutting tools. This CBN-based ultra-high pressure sintered material has excellent wear resistance and is roughly divided into two types depending on the binder phase of CBN particles forming the dispersed phase.

In other words, one of them is one in which the binder phase is composed of iron group metals or metals whose main components are iron group metals and AI, and the other is titanium nitride (hereinafter referred to as TIN) and titanium carbide (hereinafter referred to as TIC). The binder phase is composed of a ceramic compound whose main component is aluminum nitride (hereinafter referred to as NN), aluminum oxide, or the like. However, the former has high toughness because the binder phase is metal as mentioned above, but on the other hand, it easily softens at high temperatures.
Therefore, if this product is used under harsh cutting conditions that generate a large amount of heat, it will lack wear resistance and adhesion resistance, and sufficient cutting performance cannot be expected. It is something that cannot be done. On the other hand, in the latter case, as the binder phase is composed of a ceramic compound as mentioned above, it has excellent wear resistance and welding resistance, but on the other hand, it suffers from a lack of toughness. Therefore, chipping and chipping are likely to occur under cutting conditions where a large impact force is applied to the cutting edge, such as when milling high-hardness steel such as die steel. ``From the above-mentioned viewpoint, we conducted research to obtain a composite material with excellent wear resistance and toughness, as well as excellent welding resistance and thermal shock resistance. , and carbonitrides, as well as Ti and W double carbides and double carbonitrides (hereinafter referred to as TIC, TIN, TICN, (Ti
, W)C~ and (Ti" expressed as W)CN"and these are collectively referred to as T-ball (W) carbon/nitride): 20-70%, shelf Aluminum chloride (hereinafter referred to as AI&): 1 to 10% "ALFe"N
One or more of i and Co (hereinafter collectively referred to as bonded phase forming components): 0.5 to 10
%, and further contains 1 to 20% of aluminum nitride (hereinafter indicated by number N) as necessary, and the remainder is CBN and unavoidable impurities (However, CBN: 40 to 80% by volume).
The ultra-high pressure sintered material with a composition of They obtained the knowledge that it exhibits excellent cutting performance when used as a cutting tool.

This invention was made based on the above findings, and the reason why the component composition was appropriately limited as described above will be explained below.

'a} Ti(W) carbon/nitride These components have a uniform effect of improving the rutting and welding resistance of the L material, but if their content is less than 20%, the desired effect will not be achieved. However, if the content exceeds 70%, the wear resistance will decrease.
Its content was set at 20-70%.

Note that the best properties are obtained when the content is 30 to 50%. 'b} MB2 AI & component has the effect of improving the thermal shock resistance of the material, but if its content is less than 1%, the desired thermal shock resistance cannot be secured, and as a result, for example, during milling, the heat Cracks tend to occur, and if the content exceeds 10%, the material becomes brittle, so the content was set at 1 to 10%.

{c} Bonded phase-forming components These components include CBN particles that form a hard dispersed phase;
Ti(W) charcoal.

Nitride particles, NB2 particles, and if necessary, mountain N particles contained therein have a uniform effect of further improving silk-sintering properties and improving balling properties, but when the content is 0. If the content is less than 5%, the desired effect cannot be obtained, while if the content exceeds 10%, it not only reduces the hardness of the material and deteriorates the abrasion resistance, but also makes the face resistant. Since the concentration also decreases, its content is reduced to 0.
It was set at 5-10%.

'd} Mountain N The mountain N component has the effect of further improving the thermal shock resistance and welding resistance of the material.It is included as necessary when these properties are required, but its content is 1%
If it is less than 2, the desired effect of improving the action cannot be obtained.
If the content exceeds 0%, the silk-sintering property deteriorates and microvoids are likely to occur in the material, so the content was set at 1 to 20%.

[e- CBN capacity% If the proportion of CBN in the total capacity is less than 40%, CBN
However, if the ratio exceeds 8% by volume, the contact ratio between CBN particles becomes too high. As a result, CBN particles tend to fall off during cutting, leading to deterioration of wear resistance.
It was set at 80%.

When used as a cutting tool, the material of the present invention can be used as an indexable tip, either alone or in combination with a high-rigidity material such as tungsten carbide-based cemented carbide or cermet. Furthermore, these tips can also be used in a state where they are attached by brazing to the tip of a holder made of tungsten carbide-based cemented carbide, hardened steel, or the like.

Next, the ultra-high pressure bonding material of the present invention will be explained using examples and comparing with comparative examples.

Examples of raw material powders include CBN powder with an average particle size of 6 mm, TIC powder, TIN powder, and TIC powder (Tio.6WM), each of which has an average particle size of lAw.
C powder, and (Ti.

．． 55Wo. 45) CO. 7NO. 3 powder, average grain mugwort:
Prepare 1-mu kite AI&powder, 2-mu kite Nonoyama N powder, 2-mu skin AI powder, Co powder, Fe powder, and Nj powder, and mix these raw material powders into the formulations shown in Table 1. After mixing in a ball mill under normal conditions, it was milled with a diameter of 313 ribs ◇× under a pressure of 2 mm.
Thickness: Formed into a disc-shaped compact with dimensions of 1.5 fences,
These green compacts were then molded into a base material having a blending composition of Co: 16%, tungsten carbide: the remainder, and having the dimensions of diameter: 13 fence 0 x thickness 3 side under a pressure of 20 n' flow. The disc-shaped powder compacts as shown in FIG.
Ultra-high-pressure bonded materials 1 to 20 of the present invention and comparative ultra-high-pressure bonded materials that have substantially the same composition as the blended composition by ultra-high pressure sintering under the conditions of , temperature: 1300 qo, holding time: 5 minutes. 1 to 12 were produced, respectively. Comparative ultra-high pressure sintered materials 1 to 12 all have compositions in which the content of one of the constituent components (marked with * in Table 1) is outside the scope of this invention. It is.

Next, the super local pressure annealing materials 1 to 2 of the present invention obtained as a result
0 and comparative ultra-high pressure sintered materials 1 to 12, the work material: SKD-
11 (hardness: HRC62), depth: 0.2 fence, feed:
A cutting test was performed under the conditions of 0.1 cut/time, cutting speed: 60 cuts/min, and without cutting oil (hereinafter referred to as cutting test A). Round bar (hardness: HRC48), depth of cut change, feed: 0.
Intermittent cutting test (hereinafter referred to as cutting test B) was carried out under the conditions of 1x/cut and cutting speed: 60 kites/min.Work material: SKD-61 (hardness: HRC) was conducted for the purpose of evaluating thermal shock resistance.
48) A cutting test (hereinafter referred to as cutting test C) was conducted under the conditions of depth of cut: 10 ribs, feed per tooth: variation, and cutting speed: 160 min. The cutting time until the surface wear reached 0.2 ribs was measured, and the depth of cut at which chipping was observed on the cutting edge was checked in the cutting test B, and the depth of cut at which chipping was observed on the cutting edge was checked in the cutting test C. The feed rate where the occurrence was observed was checked.

These test results are also shown in Table 1. From the results shown in Table 1 of Satoshifune, the ultra-high pressure bonding materials 1 to 1 of the present invention
No. 20 showed excellent cutting performance in all cutting tests, whereas Comparative ultra-high pressure Akio material No. 1 to No. It is clear that the material exhibits inferior cutting performance in at least one of the cutting tests A to C described above.

As mentioned above, the ultra-high pressure lathered material of the present invention has excellent abrasion resistance, toughness, sagging resistance, and thermal shock resistance, so it can be used for Ni-based or Co-based superstructures that require these properties. It exhibits extremely excellent cutting performance when used as a cutting tool for cutting difficult-to-cut materials such as alloys and high-hardness steels such as die steel.

Claims (1)

[Claims] 1 Carbides, nitrides, and carbonitrides of Ti, and further T
One or more of the double carbides and double carbonitrides of i and W: 20 to 70% by weight, aluminum boride: 1 to
10% by weight, one of Al, Fe, Ni, and Co
Species or two or more species: 0.5 to 10% by weight, with the remainder consisting of cubic boron nitride and unavoidable impurities (however, cubic boron nitride: 40 to 80% by volume). Ultra-high pressure sintered material for cutting tools. 2 Ti carbides, nitrides, and carbonitrides, as well as T
One or more of the double carbides and double carbonitrides of i and W: 20 to 70% by weight, aluminum boride: 1 to
10% by weight, one of Al, Fe, Ni, and Co
A composition containing 0.5 to 10% by weight of a species or two or more, further containing 1 to 20% by weight of aluminum nitride, and the remainder consisting of cubic boron nitride and unavoidable impurities (however, cubic boron nitride: 40% by weight) 80% by volume).