JPH09157812A - Heat treating method for titanium-aluminum base alloy and vessel for heat treatment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the formation of an enbrittled layer on the surface of the material to be treated by suppressing oxidation and an element removing phenomenon therein. SOLUTION: The material 1 to be treated composed of a titanium aluminum base alloy is chared to one chamber of a vessel 3 for heat treatment whose inside is partitioned by a partition plate 5 and, furthermore, a deoxidizing material 2 composed of sponge titanium is charged to the other chamber. In that state, the vessel for heat treatment is arranged at the inside of a furnace 9, the inside of the furnace is evacuated, and, thereafter, an inert gas is injected into the inside of the furnace. After that, the temp. of the inside of the furnace is raised to a prescribed one, and the material 1 to be treated is subjected to heat treatment.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat treatment method for a titanium-aluminum base alloy and a heat treatment container used when performing the heat treatment method.

[0002]

2. Description of the Related Art For example, a titanium-aluminum base alloy is sometimes used as a component of an aircraft engine because it has excellent heat resistance and strength, and has advantages such as weight reduction. Since the titanium-aluminum-based alloy has brittleness, heat treatment is effective for improving ductility even if it is a little. Conventionally, the heat treatment of titanium-aluminum based alloy is performed in a vacuum atmosphere at 1000 ° C.
It was generally carried out under high temperature conditions exceeding 10 ° C.

[0003]

However, the conventional heat treatment method has the following problems. In other words, despite the heat treatment in a vacuum atmosphere, the element reacts with oxygen remaining in the furnace to oxidize, or a deelemental phenomenon occurs in which aluminum element jumps out. There is a problem that a layer is formed.

The present invention has been made in view of the above circumstances, and a titanium-aluminum-based alloy capable of preventing the formation of an embrittlement layer on the surface of an object to be treated by suppressing the oxidation or deelemental phenomenon. It is an object to provide a heat treatment method and a heat treatment container.

[0005]

To achieve the above object, in the invention according to claim 1, a titanium aluminum base is provided in one chamber of a heat treatment container whose interior is partitioned by a partition plate having air permeability and heat resistance. An object to be treated made of an alloy is loaded and a deoxidizing material is loaded in the other chamber, the heat treatment container is placed inside the furnace in this state, and the inside of the furnace is evacuated. It is characterized in that an inert gas is injected, and then the inside of the furnace is heated to a predetermined temperature to heat-treat the object to be treated. Since the heat treatment is performed in an inert gas atmosphere in this manner, the so-called element removal phenomenon in which the aluminum element jumps out does not occur. Further, since oxygen contained in the inert gas is absorbed by the deoxidizer, it is possible to prevent the surface of the object to be processed from being oxidized. The invention according to claim 2 is characterized in that sponge titanium is used as the deoxidizing material. Titanium sponge has a high degree of purity, is porous, and has a large surface area, so that it easily reacts with oxygen, and therefore positively absorbs oxygen contained in an inert gas. As a result, it is possible to prevent the object to be processed from being oxidized by oxygen contained in the inert gas. Further, since titanium sponge can be obtained at a relatively low cost, running cost can be reduced. According to a third aspect of the present invention, there is provided a container for heat treatment of a titanium-aluminum-based alloy, which is disposed inside a furnace for heat treatment, and which heat-treats an object loaded in the container body. The inside of the room is partitioned into at least two chambers by a partition plate with breathability and heat resistance,
One of the chambers is a to-be-processed object storage section in which a to-be-processed object is loaded, and the other chamber is a deoxidizing material storage section in which a deoxidizing material is loaded. By using such a heat treatment container, the heat treatment method according to claim 1 can be easily carried out. The invention according to claim 4 is characterized in that a communication hole for communicating the inside and outside of the container body is provided in the wall portion of the deoxidizing material storage portion in which the deoxidizing material of the container body is loaded. When the inert gas reaches the object storage part in the heat treatment container, it passes through the deoxidizing material storage part through the communication hole in the wall of the deoxidizing material storage part, so it is contained in the inert gas. Oxygen will be absorbed by the deoxidizing agent loaded here, and the object to be treated can be prevented from being oxidized by oxygen contained in the inert gas.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a flowchart of a heat treatment method for a titanium-aluminum based alloy, and FIG. 2 is a cross-sectional view showing an implementation state of the heat treatment method using a heat treatment container.

Hereinafter, the heat treatment method for the titanium-aluminum based alloy according to the present invention will be described step by step. [S1: Loading of Processing Object and Deoxidizing Material] The processing object 1 and the deoxidizing material 2 are loaded into the heat treatment container 3. The heat treatment container 3 is composed of a container body 4 whose upper opening is opened and closed by a lid 4a, and a partition plate 5 which partitions the inside of the container body 4 into upper and lower parts and which is arranged at a substantially central portion in the height direction of the container. ing. The container body 4 and the partition plate 5 are made of a material that does not deteriorate in strength even at high temperatures, for example, a composite material that uses carbon as a matrix and is reinforced with carbon fibers. The upper chamber of the heat treatment container 3 partitioned by the partition plate 5 serves as an object storage part 6 in which the object 1 is loaded, and the lower chamber is loaded with the deoxidizing material 2. The deoxidizer storage unit 7 is used. The object storage portion 6 and the deoxidizing material storage portion 7 are communicated with each other through a large number of through holes 5a, ... A communication hole 8 for communicating the inside and outside of the container body 4 is provided in the wall portion 7a of the deoxidizing material storage portion 7 of the container body 4.

As the deoxidizing material 2, titanium sponge 2A is used. The titanium sponge 2A is a porous high-purity titanium (for example, a purity of about 99.9999%), and is a raw material for producing metal titanium that is usually used. That is, an ingot of metallic titanium is obtained by stamping and solidifying the titanium sponge 2A, melting and pouring it into a predetermined mold.

[S2: Installation of Heat Treatment Container in Furnace] The heat treatment container 3 loaded with the object 1 and the deoxidizing material 2 is inserted and set in the furnace 9 for heat treatment.

[S3: Ar gas atmosphere] After the inside of the furnace 9 is evacuated, an inert gas such as argon gas is injected to replace the inside of the furnace 9 with a partial pressure inert gas atmosphere. The pressure of the inert gas in the furnace 9 is 1 to 2T.
It is about orr.

[S4: High Temperature Atmosphere] The inside of the furnace 9 is heated by the heater 10 to a predetermined temperature (for example, about 1300 ° C.), and is held for about 15 hours, and the heat treatment container 3 is held.
The article to be treated 1 loaded inside is heat-treated. The holding time may differ depending on the alloy type, SPEC, etc.

[S5: Cooling] After that, after cooling to a predetermined temperature, the inside of the furnace 9 is communicated with the outside air to atmospheric pressure,
The object 1 to be processed is taken out from the furnace 9 together with the processing container 3. When the titanium sponge 2A is oxidized by a large number of heat treatments, it may be replaced with a new one as needed at that time.

According to the above-described heat treatment method for titanium-aluminum-based alloy, the heat treatment is performed in an inert gas atmosphere, so that it is possible to prevent a so-called deelemental phenomenon in which aluminum element or the like is ejected from the object 1 to be treated. Further, since oxygen contained in the inert gas is absorbed by the deoxidizing material 2, it is possible to prevent the surface of the object to be processed 1 from being oxidized.

Since the communication hole 8 for communicating the inside and outside of the container body 4 is provided in the wall portion 7a of the deoxidizing material storage portion 7 of the container body 4, the inside of the furnace 9 is vacuum-treated and then injected. When the inert gas such as the argon gas that is generated reaches the object storage part 6 in the container body 4, it reaches the deoxidizing material storage part 7 through the communication hole 8 as shown by the arrow in FIG. The oxygen contained in the inert gas is absorbed by the deoxidizing material 2 because it passes through the deoxidizing material 2 through the through holes 5a of the partition plate 5 to reach the object storage part 6. It As a result, it is possible to prevent the object to be processed 1 from being oxidized by oxygen contained in the inert gas.

It is also conceivable to dispose titanium powder or titanium pieces around the object to be processed 1 in order to prevent the titanium contained in the object to be processed 1 from being oxidized. There is a risk that titanium pieces and the like will bond to the object to be processed 1 due to thermal diffusion. In the above-mentioned embodiment, since the object 1 to be processed and the titanium sponge 2A are separated by the partition plate 5, such a problem does not occur.

In the above embodiment, argon gas is used as the inert gas to be injected into the furnace 1. However, the present invention is not limited to this, and other inert gas such as neon or krypton is used. May be. Further, in the above-described embodiment, the heat treatment-requiring container 3 is divided into the upper and lower two chambers by the partition plate 5, but the present invention is not limited to this, and a partition plate is further provided around the object storage part 6. Provided,
A plurality of deoxidizer storage parts 7 are provided so as to surround the object storage part 6.
May be provided.

[0017]

According to the invention described in claim 1, since the heat treatment is carried out in an inert gas atmosphere, it is possible to suppress the occurrence of a deelemental phenomenon. Further, since oxygen contained in the inert gas is absorbed by the deoxidizer, it is possible to prevent the surface of the object to be processed from being oxidized. According to the invention of claim 2, sponge titanium is used as the deoxidizing material. Since sponge titanium has a high purity, is porous, and has a large surface area, it easily reacts with oxygen, and therefore, it can be used as an inert gas. Oxygen contained is positively absorbed, and therefore, the object to be processed can be prevented from being oxidized by oxygen contained in the inert gas. Further, since titanium sponge can be obtained at a relatively low cost, running cost can be reduced. According to the invention of claim 3, by using the heat treatment container, the heat treatment method of claim 1 can be easily carried out. According to the invention described in claim 4,
When the inert gas reaches the periphery of the object to be treated in the heat treatment container, since it always passes through the deoxidizing material storage portion, oxygen contained in the inert gas is absorbed by the deoxidizing material, It is possible to prevent the object to be processed from being oxidized by oxygen contained in the inert gas.

[Brief description of the drawings]

FIG. 1 is a flowchart of a heat treatment method for a titanium-aluminum based alloy.

FIG. 2 shows an implementation status of a heat treatment method using a heat treatment container.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Processing object 2 Deoxidizing material 2A Sponge titanium 3 Heat treatment container 4 Container body 5 Partition plate 5a Through hole 6 Processing object storing part 7 Deoxidizing material storing part 8 Communication hole 9 Furnace 10 Heater

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akiki Masaki 3-5-1, Mukaidaicho, Tanashi City, Tokyo Ishikawa Shima Harima Heavy Industries Ltd. Tanashi Factory Co., Ltd. Advanced Material Utilization Gas Generator Research Laboratory Tanashi Branch Room

Claims (4)

[Claims] 1. An object to be treated (1) made of a titanium-aluminum-based alloy is loaded into one chamber of a heat treatment container (3) whose inside is partitioned by a partition plate (5) having air permeability and heat resistance, and the other is The deoxidizing material (2) is loaded in the chamber of the above, the heat treatment container is placed inside the furnace (9) in this state, the inside of the furnace is evacuated, and then an inert gas is injected into the inside of the furnace. Then, after that, the inside of the furnace is heated to a predetermined temperature to heat-treat the object to be treated, and a heat treatment method for a titanium-aluminum-based alloy. 2. The heat treatment method for a titanium aluminum base alloy according to claim 1, wherein sponge titanium is used as the deoxidizing material. 3. A container (3) for heat treatment of a titanium-aluminum-based alloy, which is disposed inside a furnace for heat treatment and heat-treats an object to be treated loaded in the container body, the container body The inside of (4) is partitioned into at least two chambers by a partition plate (5) having air permeability and heat resistance, and one of the chambers is filled with an article to be treated (1) to be treated containing section (6). A container for heat treatment of a titanium-aluminum based alloy, characterized in that the other chamber is a deoxidizing material storage part (7) in which the deoxidizing material (2) is loaded. 4. The container for heat treatment of titanium-aluminum-based alloy according to claim 3, wherein the wall of the deoxidizing material storage portion of the container body, into which the deoxidizing material is loaded, communicates with the inside and outside of the container body. A container for heat treatment of a titanium-aluminum based alloy, characterized in that it is provided with holes (8).