JPH08225956A - Heat and oxidation resistant metallic heating body - Google Patents

Abstract

PURPOSE: To produce a heat and oxidation resistant metallic heating body capable of reducing a production cost. CONSTITUTION: This heat and oxidation resistant metallic heating body is obtained by applying a ceramic-mixed suspension. consisting of 20-40% silicon dioxide or zirconium oxide. 25-45% barium oxide, calcium oxide and zinc oxide, 1-15% boron oxide and alumina and 20-40% chromium oxide on a surface of a metallic base body and binding the ceramic-mixed suspension with the surface of the metallic base body at a room temp. and low temp. atmosphere. As the metallic base body, at least one selected from among iron, stainless steel, aluminum, nickel, tungsten, the other iron group metal and Ni-Cr alloys metal can be used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-resistant and oxidation-resistant metal heating body which has high temperature and high strength and is excellent in heat resistance and oxidation resistance.

[0002]

2. Description of the Related Art Conventionally, it is known that a metal surface is coated with an element resistant to high temperature oxidation by a method such as vacuum deposition, thermal spraying or diffusion to improve the oxidation resistance at high temperature (eg, JP-A-53-85736, JP-A-3-
223473).

The surface treatment method for a metal body disclosed in Japanese Patent Laid-Open No. 53-85736 is a coating metal for coating a metal body to be treated with a heat-resistant and corrosion-resistant metal by a vacuum deposition method or an ion plating method. A rare earth element is added to the inside.

Further, the method for producing a polycrystalline composite ceramic coating disclosed in Japanese Patent Laid-Open No. 3-223473 is as follows: aluminum oxide spinel, aluminum titanate, aluminum cobalt solid solution, aluminum nickel solid solution,
A polycrystalline composite powder mixture consisting of a predetermined amount of silicon, cobalt oxide, silicon iron, tantalum carbide, manganese oxide, molybdenum disilicide and spinel solid solution is mixed with a lithium silicate solution or a silicate compound solution and further suspended. Iron, stainless steel, aluminum, copper, titanium, tungsten, niobium, nickel, cobalt, other iron group, platinum group, casting alloys, refractory, etc., prepared by mixing a hydroxy compound as a stabilizer or dispersible silicic acid. Stuff,
It is applied to the surface of mortar, concrete, fiberboard, and felts, and cured and bonded at room temperature and low temperature.

[0005]

However, a high temperature resistant rare earth metal and a ceramic film is obtained by coating the surface of the above metal with a high temperature oxidation resistant element by a method such as vacuum deposition, thermal spraying or diffusion. Since the bonding strength of the base material at a high temperature is poor, if it is used for a long time in an atmosphere of about 800 to 1000 ° C. or higher, the function of the oxidation resistant film will not be fulfilled. Moreover, since an expensive device or an expensive raw material is used, there arises a problem that the manufacturing cost is increased.

An object of the present invention is to solve the above-mentioned problems, to improve the surface morphology of a metal substrate such as iron or stainless steel, and to apply it to a diesel particulate filter, engine parts or the like at a sufficiently high temperature and high temperature. It is an object of the present invention to provide a heat-resistant and oxidation-resistant metal heating element which is strong, heat-resistant and excellent in oxidation resistance and can be manufactured at low cost without using expensive equipment or expensive raw materials.

[0007]

In order to achieve the above object, the present invention is configured as follows. That is,
This invention is applicable to silicon dioxide and zirconium oxide 20-4.
0 wt%, barium oxide, calcium oxide and zinc oxide 25 to 45 wt%, boron oxide and alumina 1 to 15 wt%
%, And 20-40 wt% of chromium oxide are applied to the surface of the metal substrate, and the ceramic mixture suspension is bonded to the surface of the metal substrate in an atmosphere at room temperature or low temperature. And a heat-resistant and oxidation-resistant metal heating element.

Alternatively, according to the present invention, 20 to 40 wt% of silicon dioxide or zirconium oxide, 25 to 45 wt% of barium oxide, calcium oxide and zinc oxide, 1 to 15 wt% of boron oxide or alumina, and 20 to 40 wt% of chromium oxide.
%, And the ceramic mixture suspension was applied to the surface of the metal substrate that had been subjected to vacuum heat treatment, and the ceramic mixture suspension was solidified and bonded to the surface of the metal substrate. The present invention relates to a heat-resistant and oxidation-resistant metal heating body characterized by the above.

Alternatively, according to the present invention, 20 to 40 wt% of silicon dioxide or zirconium oxide, 25 to 45 wt% of barium oxide, calcium oxide and zinc oxide, 1 to 15 wt% of boron oxide or alumina, and 20 to 40 w of chromium oxide.
a ceramic mixed suspension of t% is prepared, the surface of the metal substrate is coated with metal or powder is subjected to a vacuum heat treatment, and the ceramic mixed suspension is applied to the surface of the metal substrate. The present invention relates to a heat-resistant and oxidation-resistant metal heating body, characterized in that a ceramic mixed suspension is solidified and bonded to the surface of the metal substrate.

In this heat / oxidation resistant metal heating element, the metal substrate is iron, stainless steel, aluminum, nickel, tungsten or other iron group metal,
It is at least one of Ni-Cr alloy metals. Moreover, this metal heating body is configured into a fiber or a wire mesh.

[0011]

[Function] The heat-resistant and oxidation-resistant metal heating element according to the present invention is
It is configured as described above and operates as follows. In other words, this heat-resistant and oxidation-resistant metal heating body applies a ceramic mixed suspension of silicon dioxide, zirconium oxide, barium oxide, calcium oxide and zinc oxide, boron oxide, alumina, and chromium oxide to the surface of a metal substrate. Then
Since the ceramic mixed suspension is bonded to the surface of the metal substrate in an atmosphere of room temperature or low temperature, the surface morphology of the metal substrate is excellent in heat resistance, the high temperature strength is enhanced and the oxidation resistance is improved, An insulating film can be formed on the surface.

[0012]

Embodiments of the heat-resistant and oxidation-resistant metal heating element according to the present invention will be described below with reference to the drawings. FIG. 1 is a graph showing the oxidation resistance ratio with respect to the oxidation time of each of the heat and oxidation resistant metal heating bodies according to the present invention and the metal heating bodies of the comparative examples.

The heat-resistant and oxidation-resistant metal heating element according to the present invention comprises silicon dioxide and zirconium oxide 20 to 40 wt.
%, Barium oxide, calcium oxide and zinc oxide 25-
A ceramic mixed suspension of 45 wt%, boron oxide or alumina 1 to 15 wt%, and chromium oxide 20 to 40 wt% is applied to the surface of a metal substrate, and the ceramic mixed suspension is applied to the metal at room temperature or low temperature atmosphere. It is solidified and bonded to the surface of the substrate.

Alternatively, the heat-resistant and oxidation-resistant metal heating body according to the present invention is produced by coating the surface of a metal substrate with the ceramic mixture by vacuum heating, plating, coating, and sintering. In this metal heating body, at least one of iron, stainless steel, aluminum, nickel, tungsten, other iron group metals, and Ni—Cr alloy metals can be selected as the metal substrate. Further, this metal heating body can be formed into a fiber or a wire mesh, and the film formed on the surface layer can be formed into an insulating film, so that it can be used as a heater or the like. With this metal heating element, when a conductive metal is selected for the metal substrate, a heater can be manufactured, and in that case, since it has heat resistance and oxidation resistance characteristics, it is necessary to regenerate the diesel particulate filter. It can be used as a heater.

Next, specific examples of the heat-resistant and oxidation-resistant metal heating element will be described. As Example 1 of the heat-resistant and oxidation-resistant metal heating element according to the present invention, the product 1 of the present invention was produced as follows. [Example 1] In this method for producing a heat-resistant and oxidation-resistant metal heating element, silicon dioxide and zirconium oxide 20 to 40 were used.
wt%, barium oxide, calcium oxide and zinc oxide 2
5 to 45 wt%, boron oxide and alumina 1 to 15 wt
%, And 20-40 wt% chromium oxide to make a ceramic mixed suspension. This ceramic mixed suspension is applied to the surface of a metal net of a wire mesh made of stainless steel (SUS304), or the surface of a metal base formed on the wire mesh,
The ceramic mixed suspension was solidified and bonded to the surface of the metal substrate. This was kept in the air at 1100 ° C. for a predetermined time to be oxidized to produce a product 1 of the present invention.

Next, as Example 2 of the heat-resistant and oxidation-resistant metal heating element according to the present invention, the product 2 of the present invention was produced as follows. [Example 2] In the method for producing this heat-resistant and oxidation-resistant metal heating element, a ceramic mixed suspension was prepared in the same manner as described above, and the same metal substrate as described above was selected. First, a metal base made of a wire mesh made of selected stainless steel (SUS304) is held in vacuum at 500 to 1050 ° C. for a predetermined time, the surface of the metal base is coated with the ceramic mixture suspension, and the ceramic mixture is mixed. The suspension was solidified and bonded to the surface of the metal substrate. This was kept at 1100 ° C. in the atmosphere for a predetermined time to oxidize it to produce a product 2 of the present invention.

As a comparative example, stainless steel (SU
The unprocessed (untreated) As-received metal substrate made of a wire mesh made of S304) is
A comparative product was prepared by holding at 0 ° C. in the atmosphere for a predetermined time to oxidize.

Next, the electrical resistance values (ohm · cm) of the oxidation resistance of the present invention product 1, the present invention product 2 and the comparative product were measured. The result is shown in FIG. In Fig. 1, the horizontal axis is 11
The elapsed oxidation time (hr) at 00 ° C. is shown, and the vertical axis shows the ratio of the electric resistance value after the oxidation treatment to the electric resistance value before the oxidation treatment. For example, in the oxidation treatment of the product 2 of the present invention, the electrical resistance value of the oxidation resistance held at 1100 ° C. for 10 hours was substantially unchanged from the electrical resistance value before the oxidation treatment. Further, when the product 2 of the present invention was held for 50 hours by the oxidation treatment, the electrical resistance value of the oxidation resistance was increased to about 4 times.
On the other hand, in the comparative product, the electrical resistance value of the oxidation resistance increased after the oxidation treatment for 10 hours, which was about 8 times the electrical resistance value before the oxidation treatment. From this result, it was found that the product 1 of the present invention and the product 2 of the present invention have excellent oxidation resistance as compared with the comparative product. Further, the present invention product 1 and the present invention product 2 were exposed to a high temperature atmosphere and then subjected to thermal shock, but no peeling phenomenon of the ceramic film occurred, and the metal substrate was well insulated by the ceramic film. I found out.

Next, as Example 3 of the heat-resistant and oxidation-resistant metal heating element according to the present invention, the product 3 of the present invention was produced as follows. [Example 3] In the method for producing this heat-resistant and oxidation-resistant metal heating element, a ceramic mixed suspension was prepared and a metal substrate was selected in the same manner as above. First, the surface of the metal substrate is plated, coated, or metal powder (iron, Ni-
Cr-based alloys, heat-resistant alloys, etc.) and, as described above, hold in a vacuum at 500 to 1050 ° C. for a predetermined time to apply the ceramic mixed suspension on the surface of the metal substrate to mix the ceramic The suspension was solidified and bonded to the surface of the metal substrate. This was kept at 1100 ° C. in the atmosphere for a predetermined time to oxidize it, thereby producing a product 3 of the invention. Therefore, the resistance value of the oxidation resistance of the product 3 of the present invention was measured. The result is shown in FIG. The oxidation resistance of the product 3 of the present invention was able to be greatly improved similarly to the oxidation resistance of the product 2 of the present invention.

[0020]

Since the heat-resistant and oxidation-resistant metal heating element according to the present invention is constructed as described above, it has the following effects. This heat-resistant and oxidation-resistant metal heating body applies a ceramic mixed suspension consisting of silicon dioxide, zirconium oxide, barium oxide, calcium oxide and zinc oxide, boron oxide, alumina, and chromium oxide to the surface of a metal substrate, Since the ceramic mixed suspension was bonded to the surface of the metal substrate at room temperature and low temperature to form a ceramic film on the surface of the metal substrate, the surface morphology of the metal substrate was excellent in heat resistance and increased in strength. It is possible to improve the oxidation resistance and form an insulating film on the surface of the metal substrate.
Therefore, this heat-resistant / oxidation-resistant metal heating element can be applied to a heater for filter regeneration used in a diesel particulate filter or the like, if a conductive metal is selected as the metal substrate. In addition, this heat-resistant and oxidation-resistant metal heating element, without using expensive equipment or expensive raw materials,
It can be manufactured at low cost.

[Brief description of drawings]

FIG. 1 is a graph showing electric resistance values of oxidation resistance with respect to elapsed oxidation time of a heat resistant / oxidation resistant metal heating body according to the present invention and a metal heating body of a comparative example.

Claims (5)

[Claims] 1. Silicon dioxide or zirconium oxide 20 to
40 wt%, barium oxide, calcium oxide and zinc oxide 25 to 45 wt%, boron oxide and alumina 1 to 15 w
t% and 20-40 wt% of chromium oxide are applied to the surface of the metal substrate, and the ceramic mixture suspension is bonded to the surface of the metal substrate at room temperature or low temperature. Characteristic heat resistant and oxidation resistant metal heating element. 2. Silicon dioxide or zirconium oxide 20 to
40 wt%, barium oxide, calcium oxide and zinc oxide 25 to 45 wt%, boron oxide and alumina 1 to 15 w
t% and 20-40 wt% chromium oxide, a ceramic mixed suspension is prepared, and the ceramic mixed suspension is applied to the surface of a metal substrate that has been subjected to a vacuum heat treatment. A heat-resistant and oxidation-resistant metal heating element characterized by being solidified and bonded to the surface of a metal substrate. 3. Silicon dioxide or zirconium oxide 20 to
40 wt%, barium oxide, calcium oxide and zinc oxide 25 to 45 wt%, boron oxide and alumina 1 to 15 w
t% and 20-40 wt% of chromium oxide to prepare a ceramic mixed suspension, which is subjected to vacuum heat treatment by coating the surface of the metal substrate with metal plating or metal powder.
A heat-resistant and oxidation-resistant metal heating body, characterized in that the ceramic mixed suspension is applied to the surface of the metal substrate and the ceramic mixed suspension is solidified and bonded to the surface of the metal substrate. 4. The metal substrate according to claim 1, wherein the metal substrate is at least one of iron, stainless steel, aluminum, nickel, tungsten, other iron group metals, and Ni—Cr alloy metals. A heat-resistant and oxidation-resistant metal heating element described in Crab. 5. The heat-resistant and oxidation-resistant metal heating body according to claim 1, wherein the metal substrate is formed of fiber or wire mesh.