JPH0271905A - Titanium compound base cermet made cutting tool excellent in anti-chipping - Google Patents

Abstract

PURPOSE:To enhance the anti-chipping so as to prevent the generation of chipping on the cutting edge even in the condition of intermittent cutting by providing a titanium carbide-nitride base cermet including 3 to 40wt.% of whisker. CONSTITUTION:A titanium compound base cermet includes 3 to 40wt.% of whisker composed of titanium carbide, titanium nitride and one or two kinds of titanium carbide-nitride. With this arrangement, it is possible to enhance anti-chipping and also improve the wear resistance.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention has excellent fracture resistance, and therefore, when used for interrupted cutting or milling cutting that requires fracture resistance, it can provide excellent cutting performance. This invention relates to a titanium compound-based cermet cutting tool that exhibits excellent wear resistance.

[Conventional technology]

Conventionally, in finishing cutting of steel, one or more of Co, Ni, and Fe (hereinafter referred to as iron group metals) as binder phase forming components = IO~2
096, Ta, Nb, W, and Mo as dispersed phase forming components
carbides, nitrides, and carbonitrides, and these two
A solid solution of more than one species (excluding nitrides and carbonitrides of W and Mo, hereinafter referred to as (Ta, Nb,
10 to 4096, and the remainder is titanium carbide (hereinafter referred to as TiC) or titanium carbonitride (hereinafter referred to as TiC) as a dispersed phase forming component. Cutting made of Tic(N)-based cermet with a composition consisting of a titanium compound (hereinafter referred to as Tic(N)) (hereinafter referred to as T1CN) and unavoidable impurities (the above is % by weight, below % is 96% by weight) (If necessary, please refer to Japanese Patent Publication No. 52-9403).

[Problem to be solved by the invention]

However, the above conventional TiC(N)! Although cermet cutting tools have high hardness, when they are used for interrupted cutting or milling, the cutting edge suffers from chipping and chipping due to insufficient fracture resistance, making them unsuitable for practical use. This is the current situation.

[Means to solve the problem]

Therefore, from the above-mentioned viewpoint, the present inventors focused on the conventional Tic(N)-based cermet cutting tool and conducted research to enable its application to interrupted cutting and milling. As a result, TiC1 titanium nitride (hereinafter T
iN), and TiCN (hereinafter referred to as T), and TiCN (hereinafter referred to as T
Whiskers made of one or more of the following (indicated by iC-N) account for 3 to 40% of the total cermet.
When the TiC(N)-based cermet is contained, it has excellent fracture resistance, and therefore, the resulting TiC(N)-based cermet cutting tool has = J ability to be applied to interrupted cutting and milling cutting, and also has its own high performance. They found that it exhibits excellent wear resistance as well as hardness.

This invention was made based on the above knowledge, and contains one or more iron group metals as a binder phase forming component: 5 to 30%, and as a dispersed phase forming component (Ta, Nb, W). ,Mo)C
A TiC(N)-based cermet containing one or more of -N = 5 to 40%, with the remainder consisting of Tic(N) as a dispersed phase forming component and inevitable impurities. , Similarly, a T1CN cermet with excellent fracture resistance, which is made of a T1CN cermet containing 3 to 40% of the total cermet whiskers consisting of one type of TiC-N or 2P1 or more as a dispersed phase forming component. This is a characteristic feature of a cutting tool made of Tic(N)-based cermet.

Next, in the cutting tool of the present invention, the reason why the component composition of the Tic(N)-based cermet constituting the cutting tool is limited as described above will be explained.

(a) Iron group metal These components have the effect of strongly bonding with the dispersed phase and improving strength and toughness, but if their content is less than 5%, the desired effect cannot be obtained. On the other hand, if the content exceeds 30%, the hardness decreases significantly and wear resistance decreases, so the content was set at 5 to 30%.

(b) (Ta, Nb, W, Mo)C-N These components have the effect of increasing the strength and hardness of cermet and improving wear resistance, but if their content is less than 5%, The desired effect of improving the above action cannot be obtained, and on the other hand, if the content exceeds 40%, the toughness will decrease and the fracture resistance will deteriorate, so the content should be reduced to 5 to 40%.
It was determined that

(c) TieφN Whisker These components have the effect of dramatically improving fracture resistance as described above, but if their content is less than 3%, the desired excellent fracture resistance cannot be secured. On the other hand, if the H content exceeds 40%, it becomes difficult to disperse and distribute it uniformly in the base material, causing local unevenness in the material, so the H content was set at 3 to 4096.

〔Example〕

Next, the Tic(N)-based cermet cutting tool of the present invention will be specifically described with reference to Examples.

As raw material powders, Tic powder, T1CN powder, and various (T
a, Nb, W, Mo) C-N powder, C.

Prepare powder, N1 powder, and Fe powder, and further
~[TiC whiskers, TiN whiskers, and T1CN whiskers having an aspect ratio (length/diameter) within the range of 00 are prepared, and these raw materials are blended into the composition shown in Table 1, and the nice force is removed. The raw material powder is mixed in a ball mill for 72 hours, then mixed lightly by applying voice force, dried, and then press-molded into a green compact at a pressure of 10Lon/cd. a) In a vacuum of I X IO'torr, temperature:
Vacuum sintering under the conditions of holding at 1420°C for 1.5 hours, (b) I X 1O-2 torr vacuum, temperature:
1400℃, pressure crab 200kg/cd, holding time: 0
．． Hot pressing for 5 hours, (c) in N2 atmosphere at 1 torr, temperature: 14
Sintering was performed in an N2 atmosphere under the conditions of holding at 70°C for 1.5 hours, sintering was performed under any of the conditions (a) to (C) above, and tl
By polishing to form the shape of S N G 432, the present invention TiC(N)-based cermet indexable chips 1 to 15 (hereinafter referred to as the present invention cermet chips) 1 to 15 and the conventional TiC(N) without whisker content are obtained. Throwaway chips made of base cermet (hereinafter referred to as conventional cermet chips) 1 to 15 were manufactured, respectively.

Next, regarding the various cermet chips obtained as a result, work material: SN CM439 (hardness: HB250)
Square timber, cutting speed: 130 rn/l1in.

A dry interrupted cutting test was conducted on steel under the following conditions: feed rate: 0.25 order/rev, depth of cut: 2 degrees, and the cutting time until the flank wear width of the cutting edge reached 0.3 mm was measured. The cutting edge condition was observed after the test. These results are shown in Table 1.

〔Effect of the invention〕

From the results shown in Table 1, the cermet chip 1 of the present invention
-15 all have excellent fracture resistance due to the inclusion of whiskers, so even if they are used for interrupted cutting, there will be no fracture or chipping on the cutting edge, and they are excellent due to their own high hardness. However, it is clear that conventional cermet chip loss and chipping occur, and that it cannot be used practically for interrupted cutting, which requires fracture resistance.

As mentioned above, the TiC(N))i cermet cutting tool of the present invention has excellent fracture resistance, so even when used for interrupted cutting or milling, there will be no damage or chipping on the cutting edge. It exhibits excellent wear resistance and excellent cutting performance over an extremely long period of time.

Claims (1)

[Claims] (1) One or more of Co, Ni, and Fe as binder phase forming components: 5 to 30% by weight; carbides, nitrides of Ta, Nb, W, and Mo as dispersed phase forming components; Contains 5 to 40% by weight of carbonitrides and one or more solid solutions of two or more of these (excluding nitrides and carbonitrides of W and Mo), with the remainder being dispersed. A titanium compound-based cermet having a composition consisting of titanium carbide or titanium carbonitride as a phase-forming component and inevitable impurities is also added with one of Ti carbides, nitrides, and carbonitrides as a dispersed phase-forming component.
Cutting made of titanium compound-based cermet with excellent fracture resistance, characterized in that it is made of titanium carbonitride-based cermet containing 3 to 40% by weight of whiskers consisting of a species or two or more species relative to the entire cermet. tool.