JPS58183244A - Heat-resistant composite material - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat-resistant composite material used for heat-resistant parts of a heat engine.

Heat-resistant alloys such as Ni-based or C-based alloys are used for heat-resistant parts. Previously, it was thought that heat-resistant parts could be made from ceramic materials in order to increase the temperature, but it was difficult to put them into practical use due to their brittleness.

For this reason, composite heat-resistant materials are known in which a heat-resistant alloy base material is coated with a ceramic layer.

However, such a composite heat-resistant material has a problem in that it cannot be used for a long period of time because the ceramic layer tends to peel off when heated.

Therefore, in order to reduce the adhesion between the wrinkled base material and the ceramic layer or the difference in thermal expansion between the base material and the ceramic layer, it is necessary to Material and cellar i, gold si in the darkness of the layer! ! the gold layer (e.g. N1-
0r, N1-AAeCoCrAtY.

Composite heat-resistant materials are being considered that include NI CrALY, F@CrAjY, etc.). However, Maeda Pikin J! No. 11 & bonding layer was formed by thermal spraying of alloy powder, so it was insufficient in terms of durability.

By the way, the following points are considered to be the factors that cause deterioration of the sill when coated with a ceramic layer.

(L) & Temperature stability (oxidation resistance of ceramic layers, metal bonding layers, etc., corrosion resistance such as high temperature corrosion).

■ Peeling due to differences in thermal expansion between the base material, metal bonding layer, and ceramic layer.

■ Failure due to thermal gradient in metal bonding layer or ceramic layer.

■ Structure instability of the ceramic layer (for example, pores).

In order to improve the above-mentioned problems, we used ZrOz-based materials, which have low thermal conductivity, are stable up to high temperatures, and have thermal expansion coefficients close to those of alloy base materials and metal bonding materials. Alternatively, a so-called cermet-based dispersion element made of Zr01 and metal is interposed between the base material and the ceramic layer to alleviate the difference in coefficient of thermal expansion (Figure 9), thereby imparting peeling resistance. Although attempts have been made to do so, the high temperature corrosion resistance and thermal shock resistance have not been fully satisfactory.

The present invention was made in view of the above circumstances, and provides a heat-resistant composite material that does not deteriorate in temperature stability and is free from destruction due to separate layers due to differences in thermal expansion between the ceramic and laminate layers, and temperature gradients in the ceramic and laminate layers. This is what I am trying to do.

4 In other words, the present invention includes a heat-resistant alloy base material, a highly porous ceramic layer bonded to the surface of the base material, and a heat-resistant alloy base material that is integrated into the base material, with the other end extending into the pores of the base material. It is characterized by comprising a dendritic reinforcing layer extending from the top to the bottom.

Examples of heat-resistant alloys in the present invention include tooth-based alloys, co
Examples include base alloys.

As the ceramic used in the present invention, for example, Zr02-
MgOj Zr02-CaO, Zr02-Y2O2vt
can be mentioned. The porosity of the ceramic layer is usually 10.
52011M! degree.

Examples of the material for the dendritic reinforcing layer in the present invention include an alloy of a base material and another metal, or an alloy of a crystalline phase and a ceramic layer, and an alloy of another metal and a gold bonding layer provided at the interface. can be mentioned.

Note that the heat-resistant composite material according to the present invention is manufactured, for example, by the following method. First, a base material made of Ni, 4, or CO-based alloy is subjected to pretreatment such as polishing and degreasing. Next, Ni-Cr, N as necessary.
1-AL, C@CrAtY, N
1CrAtY.

Deposit a metal alloy layer such as F@CrAIY and use thermal spraying method.
Apply a layer of ceramic acid. Next, this base piece is heat-treated in the coexistence of a mixed powder consisting of at least one of chromium powder, aluminum powder, silicon powder, iron powder, a ceramic powder bed, and a powder treatment agent containing halide to prevent diffusion with the base material. By doing so, a dendritic reinforcing layer is formed which is integrated with the base material and whose other end is in the pores of the cell layer near the interface of the base material.

Therefore, the heat-resistant cladding material of the present invention is provided with a dendritic reinforcing layer that is integrated with the base material and extends into the pores of the ceramic layer near the interface between the base material and the ceramic layer. The wedge action of the dendritic reinforcing layer can significantly improve the thermal shock resistance during ripening cycles, thereby preventing destruction and peeling of the ramic layer. It is also extremely effective against high-temperature corrosion of base materials caused by high-temperature oil combustion gas.
Demonstrates excellent corrosion resistance. That is, due to the presence of the branched reinforcing layer, corrosive substances and the like can permeate and diffuse through the pores of the ceramic layer, thereby preventing the ceramic layer from deteriorating or corroding the base material. An example of this will be explained.

Example 1 First, N1-15.7cr-8,23Co-3,35A
t-3,29Ti-2,5W-1,67Mo-0,7
The surface of the Nb N1-based alloy base material is degreased, and j! Alumina grid sandblasting treatment 11 was applied to the surface. Poke, N
ZrO2+ a Y, O, t 1 on the surface of the 1-based alloy base material
Single shot distance 100-150■, electric R value 800A, voltage value 3
A ceramic layer having a thickness of approximately g 00 Am was formed by thermal spraying under 4 V conditions.Then, aluminum powder was 201°, iron powder was 10%, ceramic powder containing alumina was 67%, and ammonium chloride was 3% as a powder treatment agent. In the mixed powder [1 included, heated to 1100°C in a hydrogen atmosphere, 0.
I kept the 5 o'clock tune.

As a result, a heat-resistant composite material having a ceramic layer 2 on the surface of the base material 1 and a dendritic reinforcing layer 3 between the base material and the ceramic layer was obtained as shown in Figure JI1. After completely degreasing the surface of the N1-based alloy base material with the same composition and performing sandblasting treatment with alumina grid, NICrAIY (N1-1
7Cr-6At-0,6Y) alloy powder was sprayed at a spraying distance of 1m19010m, current f[700A, 11E pressure i[
A metal bonding layer of about 200 μm was formed by thermal spraying at 32V. Then 20 g of aluminum powder, 1 l of iron powder
Dig into a mixed powder consisting of 67s of alkaline powder and 3% of ammonium chloride and heat to 110"CK in a hydrogen atmosphere.
A heat-resistant composite material was obtained by heating and holding for 0.5 hours. Therefore, the heat-resistant composite material of Example 1.2 and #I
As shown in Figure 2 (a) (heat-resistant composite material in which ceramic layer 2 is directly adhered to the surface of Nl-based alloy base material 1 (comparative example 1),
As shown in Figure (b), the thermal shock resistance, hot corozo, The properties (high temperature corrosivity) were investigated. The results are shown in the table below.

! The thermal shock resistance of the heat-resistant composite material is 1100.
This is the characteristic when the material was kept in an electric furnace at ℃1 for 5 minutes and then repeatedly heated and cooled in water. E, Tokorono, N property is 80 Na2 of table TkiK20~/d
S04-20 V2O5 (2) Combined ash t-m cloth 90
Heating in the atmosphere at 0°C or 1100°C for 3 days will result in 1 degree of damage t4't1.

As detailed above, the present invention has excellent high temperature stability,
Moreover, it is possible to provide a heat-resistant composite material suitable for heat-resistant parts of various heat engines, which has improved peeling due to differences in thermal expansion between ceramic layers and destruction due to thermal gradients in the ceramic layer.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a heat-resistant composite material showing an embodiment of the present invention, and FIGS. 2(a) and (b) are cross-sectional views of conventional heat-resistant composite materials. DESCRIPTION OF SYMBOLS 1... Nl-based alloy base material, 2... Ceramic layer, 3...
...dendritic reinforcement layer.

Claims (1)

[Claims] A heat-resistant alloy base material, a porous ceramic layer coated on the surface of this base material, and a tree branch that is integrated with the base material and has the other end extending into the pores of the ceramic layer near the interface of the base material. A heat-resistant composite material characterized by comprising a reinforcing layer of the shape.