JPH0317791B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Application Field) The present invention is an ultra-hard material suitable for firmly joining an ultra-hard material such as diamond or cubic boron nitride to a metal material such as tool steel that serves as its shank. This invention relates to a method for joining materials and metal materials.

(Prior art) Au-Ta, Au-
A common method is to use a brazing agent made of an alloy such as Nb, Ag-Cu-Ti, or Ag-Ti (for example,
French Patent No. 1332423, US Patent No.
3192620, Japanese Patent Publication No. 58-44635). However, in order to join an ultra-hard material and a metal material using the above-mentioned brazing agent, the joining part must be heated to a high temperature of 800°C or higher, which means that heat is absorbed into the ultra-hard material, which is a brittle material. It has the drawbacks of easily causing cracks due to stress and shortening the life of the ultra-hard material.

(Problems to be solved by the invention) The present invention solves the conventional problems as described above,
This method was developed with the aim of being able to firmly join ultra-hard materials to metal materials at a lower temperature than when using conventional brazing agents.

(Means for Solving the Problems) The present invention provides a structure in which Ti, Cr, Zr,
3-30% (weight%, same below) of one or more powders selected from the group of Mn, Mo, and W
A mixed compact formed by compacting 5 to 20% of Sn powder, Cu powder occupying the remainder, and additional metal powder added as necessary is sandwiched between the two, and the mixture is then heated in a vacuum.
It is characterized by heating at a temperature of 750°C or less to make it into a liquid phase, and then pressurizing it.

The mixed compact used in the present invention is made by powdering each component metal with a particle size of 5 to 100 μm and molding it into an arbitrary shape by powder compaction.
By using Sn as a main component and 5 to 20% of Sn as a subcomponent, the temperature at which liquid phase starts to form during joining is lowered to around 232°C, which is the melting point of Sn, making it possible to perform soldering at low temperatures. Sn thus plays an important role in the present invention, and 5%
If it is less than 20%, the above effects cannot be fully exhibited, and if it exceeds 20%, sufficient bonding strength cannot be obtained due to the relationship with other component metals. Ti, Cr,
Zr, Mn, Mo, and W are all metals that exhibit a high degree of adhesion to diamond and cubic boron nitride, and one or more powders selected from these groups are added to the Cu-Sn powder described above. 3 in the powder of the system
By mixing ~30%, it becomes possible to generate strong bonding force at low temperatures. These powders are mixed in the form of metal powder or metal compound powder, and if it is less than 3%, it will not be possible to generate sufficient bonding force, and if it exceeds 30%, the liquidus temperature of the mixed compact will increase. This would make it impossible to achieve the object of the present invention. In addition, powders of one or more of Ag, Zn, V, Nb, Ta, and B are mixed as additional metal powders, if necessary.
Ag acts as a catalyst to activate the bond between the ultra-hard material and the liquid-phase mixed green compact, and is useful for improving bonding strength, while Zn contributes to lowering the liquid-phase temperature. Also, V, Nb, Ta, and B are all
Like Ag, it acts as a catalyst and is useful for improving bonding strength, and these additional metal powders are added in a range of 0.01 to 1.0% from the viewpoint of balance with other components. The mixed compact consisting of these components is compacted into an arbitrary shape and then sandwiched between an ultra-hard material and a metal material, and heated at a temperature of 700 to 750 Torr in a vacuum of 10 ^-2 to 10 ^-3 Torr. heated to ℃. As a result, the mixed compact turns into a liquid phase, so if it is pressurized at a pressure of about 10 to 100 kg/ ^cm2 , the liquid phase can be applied to ultra-hard materials and metals without being disturbed by air or other gas components in a vacuum. It gets wet well and the two are firmly bonded.

In this way, the present invention uses a mixed compact containing Sn powder and Cu powder, so it is possible to lower the liquid phase start temperature.
It is possible to lower the temperature to around 232℃, which is the melting point of Sn powder, and the Sn in the liquid phase rapidly melts the entire mixed powder while melting other metal powders that are in contact with each other in a compressed state inside the mixed compact. I'll go. Therefore, according to the present invention, the entire material can be turned into a liquid phase at a much lower temperature and more quickly than in the conventional method using a brazing material that is once melted and alloyed. Therefore, according to the present invention, it is possible to bond ultra-hard materials and metal materials in a short time at a low temperature of 750°C or less, and it is possible to bond ultra-hard materials such as diamond and cubic boron nitride that are sensitive to heat. Never.

(Example) Next, preferred embodiments of the present invention will be shown.

Example 1 A mixed compact was created by mixing 10% Sn powder, 5% Ti powder, and 85% Cu powder and compacting it into a disc shape with a diameter of 3 mm and a height of 0.8 mm. Sa5
It was sandwiched between an ultra-hard material made of a diamond sintered body with a diameter of 3 mm and a tool steel with a length of 50 mm and set in a hot press furnace. Next, use a vacuum pump inside the furnace.
Under a vacuum of 10 ^-2 to ^{10 -3} Torr, heat to 750°C at a heating rate of 20°C/min, hold for 10 minutes to advance the liquid phase of the mixed powder compact, ^and then It was pressurized and cooled. As a result, the ultra-hard material made of diamond sintered body and the metal material are firmly bonded,
No cracks occurred in the ultra-hard material, and no deterioration occurred in the diamond sintered body.

Example 2 20% Su powder, 10% Ti powder, and 70% Cu powder were mixed and compacted into a plate shape of 5 x 5 x 0.8 mm, and the obtained mixed compact was molded into a plate of 5 x 5 x 20 mm. It was sandwiched between a tool steel and a 1 carat industrial diamond single crystal, and the two were bonded together at 700°C in the same manner as in Example 1.
The bond was strong and had no defects such as cracks.

Example 3 0.5% as additional metal powder in a mixture of 15% Sn powder, 5% Ti powder, 5% W powder, 75% Cu powder
A 5 mm diameter and 5 mm length made of cubic boron nitride was prepared using a mixed powder compacted by adding Ag at an external ratio and compacting it.
The ultra-hard material was joined to a cemented carbide shank. The joining method was the same as in Example 1, and 720
A strong bond was obtained at ℃.

(Effects of the Invention) As is clear from the above description, the present invention can firmly join an ultra-hard material and a metal material at a much lower temperature than when using a conventional brazing agent. This can prevent cracks and performance deterioration due to thermal stress. In addition, since the present invention uses a mixed powder compact, it is possible to perform appropriate joining depending on the shape of the joint part, and by using the metal powder as a mixed powder compact, the components can be freely changed depending on the mating material. Since it also has the advantage of being able to smoothly proceed with the liquid phase even when the liquid phase is increased, it will greatly contribute to the development of industry as a solution to the conventional problems.

Claims (1)

[Claims] 1. Ti, Cr, Zr, Mn, Mo,
3 to 30% (by weight, same below) of one or more powders selected from the W group, 5 to 20% of Sn powder, Cu powder occupying the balance, and additions added as necessary. An ultra-hard material and a metal material, which are characterized by sandwiching a mixed compact formed by compacting metal powder and metal powder, heating it in a vacuum at a temperature of 750°C or less to make it into a liquid phase, and then pressurizing it. How to join with. 2 Additional metal powders such as Ag, Zn, V, Nb,
The method of joining an ultra-hard material and a metal material according to claim 1, wherein one or more powders of Ta and B are added.