JPH06504588A - Method for producing sintered carbonitride alloy for interrupted machining of difficult-to-work materials - Google Patents

Abstract

According to the invention there now is provided a method of producing a sintered titanium based carbonitride alloy with 3-25 weight-% binder phase with extremely good properties at intermittent machining of materials difficult to machine. The method relates to the use of a raw material comprising a complex cubic carbonitride containing the main part of the metals from groups IV and V of the periodic system and carbon and nitrogen to be found in the finished alloy whereby said alloy has the composition 0.86 </= XIV </= 0.97, 0.44 </= XC </= 0.55, where XIV is the molar ratio of the group IV elements of the alloy and XC is the molar ratio of carbon.

Description

[Detailed description of the invention] Method for producing sintered carbonitride alloy for interrupted machining of difficult-to-work materials The present invention is suitable for extremely detailed machining with high cutting speeds and low feeds for semi-finishing machining. A method for producing a sintered carbonitride alloy with titanium as a main component that has exceptional properties. do.

Titanium-based sintered carbonitride alloys are commonly referred to as cermets, or Due to the high cost of traditional cemented carbides, i.e. tungsten-based alloys, has rapidly come into use in recent years.

USP 3.971.656 grows a high content of Ti and N in the core, while the outer rim has a low content of Ti and N, and a supplementary high content of Vla group metals, also points. Tarasu. As raw materials, titanium and Vl group metal carbonitride are used.

By changing this raw material, the composition of the core rim can be changed. for example , Swedish patent 459.862 contains (Ti) as a raw material.

Using Ta)C, it has a high content of titanium and tantalum and a low content of livedenum. and has a higher content of nitrogen than that of tungsten and core. This is inside Improves resistance to plastic deformation.

Furthermore, Swedish patent application 8902306-3 describes different types of the same alloy. By incorporating a type of far rim structure, the optimum alloy can be obtained. A method is disclosed that balances its advantages and disadvantages.

εP-A-259192 contains titanium and other elements in the n, v and vl groups. The solid solution is heated with air to form a solid solution, and the solid solution is pulverized into nitrogen (arsenic) powder. It is manufactured by mixing Co and/or N+ with sintering.

The raw materials should be carbon, nitrogen, and added I as components of the final alloy. The majority of at least two, preferably at least three metals from group V and group V, preferably Preferably >90%, most preferably >95%. If a sintered carbonitride alloy is manufactured as a final product using nitride raw materials, a unique structure is required. As a result, unique characteristics were obtained. Preferably, all the nitrogen is carbonitrided as described above. Exist in raw materials.

Specifically speaking, all titanium and tantalum are used as raw materials for the present invention. Contain. Preferably further vanadium, niobium and suitably further zirconium. When aluminum and haunium are used as constituent parts of the final sintered alloy, they must be included. . Metal from group vI, Cr.

When Mo and W are contained, multi-charcoal materials, car type carbon materials, and /or it is added as a metal ten carbon, but if the raw material of the present invention is cubic system, It may be a constituent part of this raw material.

The raw materials related to the present invention are directly produced by carbonitriding of metal oxides or the metal itself. Manufactured in As a result, we have essentially equiaxed grains with a narrow grain size distribution. The carbonitride powder has an average grain size of 0.8-3 μm, preferably I-2 μm. obtained in the state.

In addition to slightly changing the composition of the raw material, it is crushed, then compressed and sintered. The method is preferably carried out under an inert atmosphere.

Figure 1 shows the group IV-group V-C-N expressed in molar ratio of the composite raw material exhibiting the above-mentioned advantages. This is an enlarged view showing Window J in the composition diagram of 2 is a diagram showing the position of this small region in the overall molar ratio diagram.

Group 1 metals are Ti, Zr and/or Hf, and group V metals are V, Nb and/or Or Ta.

As can be seen from FIG. 1, the window comprises the following compositional regions:

0.84≦X +v≦0.97 0.44≦Xc≦0.55 in particular, 0.86≦Xl? ≦0.95 0.46≦X1≦0.53 The latter limiting window is divided into two types, one of which contains other group V metals besides Ta. Without weighing, it is as follows.

0, 905≦X9,・≦0.95 0.46≦Xe≦0.53 And other types contain V group metals below Ta, that is, V and Nb, and the following That's right.

0.86≦X+v≦0.905 0.46≦X, ≦0.53 Specifically, good characteristics can be obtained with each of the following compositions.

0.91≦X　If≦0o95 0.46≦X, ≦0.50 as well as 0.86≦X +v≦0,90 0.49≦Xe　≦0.53 For titanium, apply XT+>0.7, preferably XAl>0.75. Ru.

In the above molar ratio of carbon and nitrogen, the amount of oxygen is <0.8%, preferably less than 0.5%. Although it is desirable to maintain a normal amount of oxygen, i.e. carbon may be replaced with nitrogen. The present invention applies to stoichiometric carbonitrides as well as conventional substoichiometric carbonitrides. Contains carbonitrides.

example Composite raw materials related to the present invention (Tio, *s+ Taa, os+ Nba, os) (Co, s++No, = s) and the simple raw materials TiN, Tic and VC. Titanium-based carbonitride with 17.5% Ni+Co binder phase using both raw materials An alloy was produced. In both cases, WC and Mote were added in addition to CO and Ni. . Compression pressure after crushing (milling) and porosity after sintering to achieve the same grain size The degree was obtained as follows.

Porosity compression Pressure N/mm” Alloy according to the present invention AOO154 Simple raw materials AO6-AO8206 O4 international search report international search report PC'r/SE 91100888

Claims (1)

[Claims] 1. With a binder phase of 3-25% by weight by grinding, pressing and sintering using known methods. In the method of producing a sintered titanium-based carbonitride alloy, the A complex cube containing most of the metals from groups IV and V of the periodic table, as well as carbon and nitrogen. A raw material containing crystalline carbonitrides is used, thereby making the alloy 0.86≦XIV≦0.97 0.44≦Xc≦0.55 However, XIV is the molar ratio of group IV elements in the alloy, and Xc is the molar ratio of carbon. , the composition of A manufacturing method characterized by having the following. 2. The carbonitride feedstock has essentially equiaxed grains with an average grain size of 0.8-3. with a narrow grain size distribution of 1-2 μm, preferably 1-2 μm. A method according to claim 1, characterized in that: 3. The composition of the composite raw material is: 0.86≦XIV≦0.95 0.46≦Xc≦0.53. The method according to claim 1 or 2. 4. The raw material is produced directly by carburizing and nitriding metal oxides or the metal itself. Method according to any one of the preceding claims, characterized in that: