JP2621301B2 - Tungsten carbide based cemented carbide cutting tool - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention has high toughness and high hardness, and particularly, Al, Cu ₆ ,
When used for cutting non-ferrous metals such as alloys and non-metals such as wood, chipping and chipping due to insufficient toughness do not occur on the cutting edge, and excellent wear resistance over a long period of time. It relates to a tungsten carbide (hereinafter WC) based cemented carbide cutting tool that demonstrates its performance.

[Conventional technology]

Generally, in the above cutting of non-ferrous metals and non-metals, Co: 3 to 16% is contained as a binder phase forming component by weight% (hereinafter,% indicates weight%), and the rest consists of WC and unavoidable impurities It is well known that a cutting tool made of a WC-based cemented carbide having a composition is used.

[Problems to be solved by the invention]

However, in the above-mentioned conventional WC-based cemented carbide cutting tools, when the Co content is reduced due to the requirement of wear resistance, chipping and chipping are likely to occur on the cutting edge due to insufficient toughness, while ensuring high toughness At present, when the content of Co is increased for the purpose of improving the wear resistance, the abrasion resistance is remarkably reduced.

[Means for solving the problem]

In view of the above, the present inventors have developed a WC-based cemented carbide cutting tool having both toughness and abrasion resistance. As a result of focusing on the research and conducting research, when the B content is added to the WC-based cemented carbide with the Co content as a binder phase forming component relatively low, the B component reacts with the Co component. While sintering proceeds, sinterability is improved, low-temperature sintering becomes possible, and as a result, sintering is completed at low temperature, so that formation of WC-WC skeleton is significantly suppressed, The toughness of the alloy is dramatically improved, and furthermore, a part of the Co component forms a hard intermetallic compound with the B component, whereby the proportion of the free Co phase is substantially smaller than the Co content. It has been found that the wear resistance (hardness) is also improved because of the reduced amount.

The present invention has been made based on the above findings, and contains Co: 0.5 to 4.5%, B: 0.01 to 0.5% as a binder phase-forming component, and the remainder is WC as a hard dispersed phase-forming component. WC that has a composition consisting of unavoidable impurities and, especially when used for cutting non-ferrous metals and non-metals, exhibits excellent cutting performance due to its high toughness and excellent wear resistance over a long period of time It is characterized by a cutting tool made of a base cemented carbide.

In the WC-based cemented carbide cutting tool of the present invention,
The reason that the Co content is defined as 0.5 to 4.5% is that the content is 0.5%
If the content is less than 4.5%, the desired high toughness cannot be ensured. On the other hand, if the content exceeds 4.5%, the abrasion resistance is reduced. If the content is less than 0.01%, it is difficult to secure the desired toughness and wear resistance, whereas if the content exceeds 0.5%, the intermetallic compound of Co and B is Is too large and the toughness is reduced.

〔Example〕

Next, the cutting tool according to the present invention will be specifically described with reference to examples.

As raw material powder, WC powder with average particle size: 1 μm, 1.2 μ
m Co powder, 1.2 μm B powder, and 1.2 μm WB
Powders are prepared, and each of these raw material powders is blended in the composition shown in Table 1, crushed and mixed in a ball mill for 72 hours, pressed into a green compact, and is each shown in Table 1 in a vacuum. The cutting tools 1 to 8 of the present invention, the comparative cutting tools 1 to 6, and the conventional cutting tools 1 and 2 having substantially the same composition as the blended composition by sintering under the conditions and finally polishing to the shape of SNP432. Was manufactured respectively.

Each of the comparative cutting tools 1 to 6 has a component content of any one of Co and B (marked with * in Table 1) outside the scope of the present invention.

Next, various cutting tools obtained as a result are described. The work material: Al-14.5% Si alloy, Cutting speed: 500m / min, Feed: 0.1mm / rev., Depth of cut: 1mm, Cutting oil: None. Measure the cutting time until the blade wear reaches 0.2mm,
The wear resistance and toughness were evaluated by observing the damage state of the cutting edge after cutting. The results are shown in Table 1.

〔The invention's effect〕

From the results shown in Table 1, the cutting tools of the present invention 1 to 8
Have excellent wear resistance and toughness,
While excellent cutting performance is exhibited over a prolonged period, the content of at least one of Co and B falls outside the scope of the present invention, and comparative cutting tools 1 to 6, and conventional cutting tools 1, 2 is one of wear resistance and toughness,
Alternatively, it is clear that both exhibit inferior service life because both are inferior.

As described above, the cutting tool made of a WC-based cemented carbide according to the present invention has excellent toughness and wear resistance. It demonstrates.

Claims (1)

(57) [Claims] 1. A composition comprising at least 0.5% to 4.5% of Co and 0.01% to 0.5% of B as a binder phase-forming component, and the balance consisting of tungsten carbide as a hard dispersed phase-forming component and unavoidable impurities. A tungsten carbide-based cemented carbide cutting tool suitable for use in cutting non-ferrous metals and non-metals, characterized in that the cutting tool is made of a tungsten carbide-based cemented carbide having the formula (1).