JPH0397679A - Production of metal/ceramics composite - Google Patents

Abstract

PURPOSE:To obtain the composite having excellent wear resistance, heat resistance, strength, electrical conductivity, and thermal conductivity by subjecting the concentrical laminate of metallic cylindrical bodies and ceramics cylindrical bodies to diametral reduction working, then to a heating treatment at a specific temp. CONSTITUTION:The concentrical laminate is formed by concentrically and alternately disposing plural pieces of the metallic cylindrical bodies and the ceramics cylindrical bodies. This concentrical laminate is subjected to the diametral reduction working. The concentrical laminate after the diametral reduction working is subjected to the heat treatment at the temp. below the m.p. of the above-mentioned metal, by which the desired metal/ceramics composite is obtd. The diametral reduction working stage and the heat treatment stage are preferably executed alternately plural times after the stage for producing the concentrical laminate. The method for forming the concentrical laminate is exemplified by a multifilament method to be executed by forming the ceramics to extremely fine multicores, a jelly roll for winding the sheet like ceramics and metal in multiple layers, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a metal-ceramic composite that is applied to sensors, functionally gradient materials, superconducting conductors, magnets, cables, and the like.

[Prior art and its problems] Conventionally, metal-ceramic composites have been obtained by forming raw material powders of tungsten-tungsten carbide, copper-alumina, aluminum-alumina, silver cadmium monoxide, etc. into a desired shape. There is. These metal-ceramic composites have characteristics such as wear resistance, heat resistance, high strength, good electrical conductivity, and good thermal conductivity. For this reason, it is used in electrical contact materials, processing tools, mechanical structural members, etc.

However, these metal-ceramic composites
Although it is inexpensive, it does not have fully satisfactory characteristics.

In addition, as a gold band/ceramic composite, for example, a ceramic coated on a metal such as a titanium boride coated on Hastelloy, or a metalized metal such as copper, nickel, tungsten, etc. on alumina. There are ceramics with metallization on them. These metal-I-ceramic composites are used in mechanical parts such as cutting tools, electronic equipment parts, and turbine blades.

However, these metal-ceramic composites also
Although it is inexpensive, it does not have fully satisfactory characteristics.

Furthermore, as a metal-ceramic composite, carbon,
There are CFRM (ceramic fiber reinforced metal), which is a composite of silicon carbide, alumina, etc. filaments or whiskers with metal, and MFRC (metal fiber reinforced ceramic), which is a composite of metal filaments and ceramics.

In these metal-ceramic composites, the reinforcing metals and ceramics improve the strength and toughness of the composite. For this reason, efforts are being made to put this composite into practical use.

However, these metal-ceramic composites
It is more expensive than the above two types of metal-ceramic composites. For this reason, the applications of these metal-ceramic composites are limited.

N b T 1 s N b i S n SN b
3A! When combining metal-based superconductors such as l, V 3 G g, etc. with metal, C is added around the metal-based superconductor.
A conductive metal such as uSA, 77, etc. is arranged and plastically worked to make it ultra-fine and multi-core or multi-layered. These composites are electrically stable due to the conductive metal surrounding the metallic superconductor.

However, since these metal-based superconductors are scarce as resources, their cost is high and their use is limited. Furthermore, since the superconducting properties of metallic superconductors are exhibited at liquid helium temperatures, expensive liquid helium is required when using metallic superconductors.

On the other hand, in recent years, oxide-based ceramic superconductors having high critical temperatures have attracted attention. Oxide-based ceramic superconductors can exhibit superconducting properties when cooled with inexpensive liquid nitrogen, so they can be applied to various uses. Examples of such materials include LnBaCui 07-X (Ln: rare earth element), B i2 S r2 CaCu2 0B s (B
it-x P bx ) 2 S r2 Ca2 (:
u3 010, T () 2 B a 2 C a C
u 2 0 g, Tl 2 Ba2Ca2 CLI3
010-T(l Ba2 Caz CLI3 0a9
etc.

When forming an oxide ceramic superconductor into a wire rod, the following method is used since the oxide ceramic superconductor does not have plastic workability.

The first method is to mix oxide-based ceramic superconductor raw material powder with an organic binder and extrude the mixture into a desired shape. The second method is to fill a metal pipe with oxide-based ceramic superconductor raw material powder and then extend the pipe. The third method involves melting and spinning oxide-based ceramic superconductor raw material powder.

However, oxide-based ceramic superconducting wires obtained by these methods have poor thermal conductivity. Therefore, it is not possible to stably supply a large current. Therefore, this oxide-based ceramic superconducting wire cannot be used for cables or the like. Furthermore, oxide-based ceramic superconductors undergo a so-called quench phenomenon in which the superconducting state is destroyed by exceeding a critical state due to electromagnetic phenomena. Therefore, it is necessary to combine the stabilizing material and the oxide-based ceramic superconductor so that all or part of the superconducting current flows well in the portion where the quench phenomenon occurs. However, as with metal-based superconductors, multicore or multilayer structures have not been achieved.

The present invention has been made in view of the above points, and it is possible to efficiently produce a metal-ceramic composite having properties such as excellent wear resistance, heat resistance, strength, electrical conductivity, and thermal conductivity. The object of the present invention is to provide a method for manufacturing a metal-ceramic composite that can be easily manufactured.

[Means for Solving the Problems] The present invention includes a step of forming a concentric laminate by alternately arranging a plurality of metal cylindrical bodies and ceramic cylindrical bodies concentrically;
It is characterized by comprising the steps of: performing a diameter reduction process on the concentric laminate; and subjecting the concentric laminate after the diameter reduction process to a heat treatment at a temperature above the sintering temperature of the ceramic and below the melting point of the metal. This is a method for manufacturing a metal-ceramic composite.

Here, it is preferable that the diameter reduction process and the heat treatment process are performed alternately a plurality of times after the concentric laminate manufacturing process.

The metal to be composited with ceramics should be one that allows the resulting composite to exhibit excellent properties such as electrical conductivity, thermal conductivity, ductility, toughness, weldability, plating performance, and solderability. good. As such, Cu,
AN% AgSAu, FeSNi, CoSW, Mo,
Nb, TaSTi, Zr, and their alloys, Ag-
Pd, Cu-Zn, Cu-Sn, stainless steel, Fe-N
Examples include alloys such as i, Fe-Ni-Co, and Mo-Cr-Fe.

Any ceramic may be used as long as the resulting composite exhibits excellent properties such as wear resistance, heat resistance, magnetism, and superconductivity.

As such, Afl203, SiC, Zr○
2 YSZ (yttria stabilized zirconia) Mg
O, BaTiO, , Fe2 03, Y Ba 2
C tJ 3 07-x sB i2S rCaCu2
0s, B l +, P bo4S r2 Ca, Cu3
0rosT47 2 Ba, CaCu 2 0
s , Tjll2 B a2 C a2
C us C) + o, TO Ba2 Ca2Cu3
0a. s and their precursors.

Methods for making concentric laminates include the multifilament method, which involves making ceramics into ultra-fine multi-core layers, and the jewelry roll method, which involves winding multiple layers of sheet-shaped ceramics and metals, which are methods used to stabilize ordinary metal-based superconductors. can be used. Also, particularly when the ceramic is a superconductor, the superconductor may be subdivided and distributed in the matrix of stabilizing material. At this time, the metal serves not only as an electrical path but also as absorbing heat generated during quenching.

The present inventors have discovered that the structure shown in FIGS. 1 to 3 is
It has been found that this method is effective for combining ceramics and metals, which are difficult to process.

In FIG. 1, a concentric laminate 1 has metal cylindrical bodies 11 and ceramic cylindrical bodies 12 arranged alternately, and the center is made of ceramic. In addition, in FIG. 2, the concentric laminate 1 has metal cylindrical bodies 11 and ceramic cylindrical bodies 12 arranged alternately, as in FIG. 1, and the center is metal. In FIG. 3, the center is an empty core, and metal cylindrical bodies 11 and ceramic cylindrical bodies 12 are arranged alternately. By creating a structure with a cavity in the center as shown in Figure 3, it is possible to flow a refrigerant such as liquid nitrogen into this cavity, which improves the cooling effect in addition to stabilization due to compounding with metal, and improves quenching. It is extremely superior.

In order to obtain the structure shown in FIGS. 1 to 3, the following method is preferable.

First, metal is processed into a cylindrical body with a desired outer diameter using a lathe or the like. Next, similarly, ceramic powder is used to form a cylindrical body with a desired outer diameter. Thereafter, the respective cylindrical bodies are fitted alternately to form a composite of metal and ceramics. At this time, the ceramic cylindrical body is processed by cold isostatic press (CIP) or hot isostatic press (HIP).
, or use a molded body formed by preliminary sintering or the like.

Another method, as shown in FIGS. 4 and 5, is to tuft ceramic powder into the gap 14 of the metal cylinder 13, which is closed at one end, and seal the other end. Alternatively, molten ceramic may be flowed into the gap 14 of the metal cylinder 13 to seal the other end. This method facilitates diameter reduction of the concentric laminate. When the ceramic is an oxide-based superconductor, oxygen is required to develop its characteristics, so the heat treatment is preferably performed in an oxygen-containing atmosphere.

[Effect]

According to the method for producing a metal-ceramic composite of the present invention, a plurality of metal cylindrical bodies and ceramic cylindrical bodies are arranged concentrically and alternately to form a concentric laminate, and then the concentric laminate is After that, the concentric laminate is subjected to a heat treatment at a temperature above the sintering temperature of the ceramic and below the melting point of the metal. Diameter reduction processing and heat treatment are repeated as necessary.

This causes a portion of the ceramic or its precursor to melt, and when cooled and recrystallized, the ceramic crystals are oriented in the longitudinal direction of the composite.

Therefore, the excellent characteristics of ceramics are exhibited. Furthermore, since it is composited with metal, the electrical conductivity and thermal conductivity are improved compared to ceramics alone, and the composite becomes more stable. The quench phenomenon, which is a phenomenon peculiar to ceramics, is prevented.

[Example code] Embodiments of the present invention will be described below with reference to the drawings.

Example 1 First, B i,O, , S rco3, CaCO,, C
uO powder Bi:Sr:Cg:Cu-2:2:1:2
They were weighed and mixed so that The mixed powder was calcined in air at 850° C. for 5 hours.

The powder after calcining was thoroughly pulverized. The pulverized powder is made into a rod shape with a length of 100 mm and an outer diameter of 4 mm, and a length of 100 mm.
+ em pipe-shaped with an outer diameter of 11 mIlφ and an inner diameter of 7 lIIIφ, a vibrator-shaped one with a length of 100 mm and an outer diameter of 18 m1φ and an inner diameter of 14 mm, and a length of 100 mm.
It was molded into a vibrator with an outer diameter of 25 mm and an inner diameter of 21 mm. The shape of the powder is made by cold isostatic pressing (CI).
P) It was done by law.

Next, an Ag rod having a length of 120+w and an outer diameter of 30 mrsφ was processed into a metal cylinder with one end closed as shown in FIG. In addition, the size of the three gaps is each 100 mm in length.
mm x outer diameter 11 m φ x inner diameter 7 mm φ, length 100 m
+eX outer diameter 18mmφ x inner diameter 14mmφ, length 100m
m x outer diameter 25 mm φ x inner diameter 21 open φ.

A molded body formed from powder was fitted into the Ag metal cylinder processed as described above. Thereafter, the other end of the Ag metal cylinder was sealed. A metal cylinder made of Ag with both ends closed was subjected to hot isostatic pressing (HIP) under conditions of 700° C. and 1000 atm.

Swaging the metal cylinder after HIP treatment to reduce the outer diameter to 10! It was set as IIIφ. The metal cylinder after this swaging process was rolled to produce a wire rod having a thickness of 6.0 ma.

Next, the obtained wire rod was subjected to heat treatment at 920° C. for 1 hour in air. Furthermore, this wire was heat-treated in air at 850° C. for 50 hours to obtain a metal-ceramic composite.

The critical current density (J
c) and distribution ratio (F) were measured. The results are shown in Table 1 below. Note that the critical current density is 77K, 0. IT
(Tesla) magnetic field. Orientation rate (F) is X
It was measured using a line diffraction device, and calculated using the following formula using the results.

F - (Pa Poo) / (I Pao
)P(10-Σ I(OON)/Σ I(hkR) where I(hkp) indicates the peak intensity of X-ray diffraction in the plane of the crystal with Miller index [hkNJ. POO is
The peak intensity ratio of X-ray diffraction of a non-oriented ceramic material is shown. Po indicates the peak intensity ratio of X-ray diffraction of the measurement sample.

Examples 2 to 6 Metal-ceramic composites were obtained in the same manner as in Example 1, except that the metal cylinders were rolled to the thickness shown in Table 1 below. In addition, for those with a metal cylinder thickness of 2.0 mm or less, the metal cylinder after HIP treatment is swaged.
The outer diameter was set to 5 mm.

The critical current density (J
c) and orientation 'J(F) as in Example 1.
Established. The results are also listed in Table 1 below.

Comparative Examples 1 to 6 Examples except that the wire rod after rolling was not subjected to heat treatment at 920°C for 1 hour in air and the metal cylinder was rolled to the thickness shown in Table 1 below. A metal/ceramic composite was obtained in the same manner as in 1. In addition, when the metal cylinder has a thickness of 2.0 mu or less, the metal cylinder after the HIP treatment is subjected to swaging processing to have an outer diameter of 5 mm.

The critical current density (J
c) and orientation* (F) were measured in the same manner as in Example]. The results are also listed in Table 1 below.

Table 1 As is clear from Table 1, the metal-ceramic composites (Examples 1 to 6) obtained by the method of the present invention had a high crystal coordination ratio and exhibited excellent superconducting properties. On the other hand, in the metal-ceramic composites obtained by the conventional method (Comparative Examples 1 to 6), the crystals were not oriented at all and the superconducting properties were poor.

Example 7 First, TiB2 powder was coated with a length of 1. O O m+1, a vibrator with an outer diameter of 7 amφ and an inner diameter of 4 mm, length 1
0 0 mm, outer diameter 14IIIφ, inner diameter 1. 1
A vibrator with a length of 100 m+w, an outer diameter of 21 mmφ and an inner diameter of 18 mm, and a pipe-shaped one with a length of 100 mm and an outer diameter of 28 mm and an inner diameter of 2 mm.
It was molded into a vibrator with a diameter of 5IIIφ. The powder was molded by cold isostatic pressing (CIP).

Next, N with a length of 120 mm and an outer diameter of 3B++uiφ
A rod manufactured by I was processed into a metal cylinder with one end closed as shown in FIG. The sizes of the four gaps are each 100 mm in length x 11 mm in outer diameter x 7 III m in inner diameter.
Length lOOIII+1 x outer diameter 18mmφ x inner diameter 14mmφ
, Length 100mm x Outer diameter 2511! Iφ×inner diameter 2l×φ. Further, a Ni rod having a length of 100w and an outer diameter of 41IIlφ was prepared.

A hollow shaped body formed from powder was fitted into the Ni metal cylinder processed as described above. Further, a Ni rod was fitted in the center. After that, the other end of the metal cylinder made of Ni was sealed. A Ni metal cylinder with both ends closed at 800℃ for 2
Hot isostatic pressing (I{I P) treatment was performed for 4 hours under conditions of 000 a tm.

}{The metal cylinder after the IP treatment was hot extruded at a temperature of 800°C. Subsequently, the extruded metal cylindrical body was subjected to drawing processing using a draw bench to produce a tribute material having an outer diameter of 7.5 mIIφ.

Next, the obtained specimen was subjected to HrP treatment for 18 hours under the conditions of 1300°C and 2000 atm to obtain Ni-
A T i B2-based metal/ceramic composite was obtained.

The obtained N i -T i B2 complex was cut into pellets. Using this pellet, the wear test and contact voltage drop of the Ni-TiB2-based composite were investigated. The results are shown in Table 2 below. In addition, the wear test was conducted under a load of 10g.
1 The sliding speed was 10 cm/sec. The contact voltage drop was measured when a current of 0.18% was applied.

Example 8 Ni-NiB2P was produced in the same manner as in Example 7, except that a 1:1 mixture of NiB2 powder and PdB powder was used instead of TiB2 powder.
d A B-based metal/ceramic composite was obtained.

The P,5 wear test and the contact voltage drop of the obtained Ni-NiB2-PdB composite were examined using the same method as in Example 7}. The results are also listed in Table 2 below.

Comparative Example 7 1 Under the conditions of 300°C and 2000a tr7), the same procedure as in Example 7 was carried out for μ and κ without HIP treatment for 18 hours, and Ni-TiB2-based gold-recommended
A ceramic composite was obtained.

The wear test and contact voltage drop of the obtained Ni-TiB2 composite were investigated in the same manner as in Example 7.

The results are also listed in Table 2 below.

Comparative Example 8 Under the conditions of 1300°C and 2000a tm, 18
A Ni NiB2 PdB metal-ceramic composite was obtained in the same manner as in Example 8, except that the HIP process was not performed.

The wear test and contact voltage drop of the obtained Ni-NiB2-PdB composite were investigated in the same manner as in Example 7. The results are also listed in Table 2 below.

Comparative Example 9 Ni-3νol%The2 was prepared by ordinary powder metallurgy method.
A system-dispersed alloy was manufactured.

The wear test and contact voltage drop of the obtained Ni-3vol%The2-based dispersed alloy were investigated in the same manner as in Example 7. The results are also listed in Table 2 below.

Table 2 As is clear from Table 2, the metal-ceramic composites (Examples 7 and 8) obtained by the method of the present invention had a small amount of wear and a small voltage drop. In contrast, the metal-ceramic composites obtained by conventional methods (Comparative Examples 7 to 9) had a large amount of wear.

[Effects of the Invention] As explained above, the method for producing a metal/ceramic composite of the present invention can be applied to metal/ceramic composites having excellent properties such as abrasion resistance, heat resistance, strength, electrical conductivity, and thermal conductivity. This is a method for manufacturing a metal-ceramic composite that can efficiently and easily manufacture a ceramic composite.

[Brief explanation of drawings]

FIGS. 1 to 3 are explanatory diagrams showing the structure of a concentric laminate used in the method of the present invention, FIG. 4 is an explanatory diagram showing an example of a metal cylinder used in the present invention, and FIG. IV-IV in Figure 4
'This is a cross-sectional view. DESCRIPTION OF SYMBOLS 1... Concentric laminate, 11... Metal cylindrical body, 12.
...Ceramic cylindrical body, 13...Metal cylinder, 14
...Hat.

Claims (1)

[Claims] A process of forming a concentric laminate by alternately arranging a plurality of metal cylindrical bodies and ceramic cylindrical bodies in a concentric manner, a process of performing a diameter reduction process on the concentric laminate, and a concentric laminate after the diameter reduction process. A method for producing a metal-ceramic composite, comprising the step of: performing heat treatment at a temperature higher than the sintering temperature of the ceramic and lower than the melting point of the metal.