KR101415632B1 - Refractories manufacturing equipment using the crystallization furnace of sapphire made the stabilized zirconia bead minimized the content of yttria - Google Patents

Abstract

The present invention relates to a refractory manufacturing apparatus used in a sapphire single crystal growth furnace made of melt stabilized zirconia beads with minimized yttria content.
According to the present invention, A melting furnace which is rotatable in one direction on the support and melts zirconia containing yttria by a high frequency skull melting method; A high-pressure air injection unit positioned at a lower portion of the melting furnace and injecting high-pressure air toward the molten zirconia falling from the melting furnace to produce melt-stabilized zirconia beads; And a refractory forming unit located below the high-pressure air injection unit, disposed in a direction in which the melting furnace is tilted to form the refractory by laminating the melt-stabilized zirconia beads; So that it is possible to insulate the superheated heat inside the sapphire single crystal growth as well as perform the heat insulation.

Description

TECHNICAL FIELD [0001] The present invention relates to a refractory manufacturing apparatus for use in a sapphire single crystal growth furnace made of a melt-stabilized zirconia bead having a minimized yttria content. BACKGROUND ART [0002]

The present invention relates to a refractory manufacturing apparatus for use in a sapphire single crystal growth furnace made of melt stabilized zirconia beads in which the yttria content is minimized, and more particularly, to a refractory manufacturing apparatus for minimizing the yttria content (20 wt%? 5 wt% It is possible to heat the superheated heat inside the sapphire single crystal growth by performing the bead refractory growth and to perform the heat insulation while minimizing the volume expansion due to the phase transformation even when the yttria content is minimized, It is possible to manufacture refractories, so that the melting temperature of the barium aluminate used as an adhesive in the conventional refractory made of cubic zirconia is low, thereby shortening the life span and eliminating the quality deterioration due to gas emission, Melt stabilized zirconia beads with minimized yttria content To a refractory manufacturing apparatus for use in a sapphire single crystal growth furnace.

Generally, refractories are high temperature resistant materials, which do not soften at a temperature of at least 2,000 ° C or more, maintain their strength sufficiently, and can withstand chemical abuse, etc. As a material of sapphire single crystal growth Apparatus is used to insulate superheated heat or perform insulation.

The sapphire single crystal growth is to provide a compound semiconductor single crystal Epi layer such as GaN or GaAIN which can be deposited on a sapphire substrate, which is an essential material for LED manufacturing.

The Sapphire single crystal growth method currently in commercial use for sapphire single crystal growth includes Kyropoulos method, Czochralski method, Heat Exchange Method (HEM), Vertical Horizontal Gradient Freezing (VHGF) method, Edge-Defined Film- ) Method is used. The sapphire single crystal produced by this method is formed by melting a high purity (99.99%, 4N grade or higher) alumina (Al 2 O 3) powder or the like at a temperature of 2,300 ° C. or higher and slowly cooling the crystal by growing it.

Metal molybdenum was first used as a refractory material for sapphire single crystal growth as described above. Even though the molybdenum refractory 10 made of the molybdenum plate having a thickness of 0.5 mm is rolled up to 10 layers, it is deformed due to the high temperature during use and its life is short as 6 months to 1 year, which is not economical. Recently, cubic zirconia And they are ground and bonded with a water-soluble material to produce a brick state (see FIG. 1).

As described above, 20 wt% of Yttria (Y2O3), which is a high price, is contained in the production of the refractory 10 using cubic zirconia. It takes about 80 hours (melting 4 hours, And 76 hours of crystal growing) are required to increase the production cost.

Particularly, in the conventional method, cubic zirconia is crushed and an adhesive containing barium aluminate (BaAl 2 O 4) of 7 wt% is used. However, since the melting temperature of barium aluminate is as low as 1,815 ° C., The quality of the sapphire crystal is deteriorated, and the life span is shorter than expected for less than 2 years.

As shown in FIG. 2, the refractory made of cubic zirconia has a weight of about 160 kg in the case of a large capacity, and is difficult to manufacture, so that the refractory is assembled into 42 pieces.

In addition, this method is inconvenient to use even though the electricity consumption is reduced by about 20% due to the high insulation effect compared with the refractory made of molybdenum.

On the other hand, recently, zirconia (ZrO 2), which is a refractory material capable of withstanding rapid temperature changes in a sapphire single crystal growth furnace, has been used. The zirconia shows various phase changes according to the temperature change. At room temperature, the zirconia is in a monoclinic state. The zirconia is transformed into a tetragonal structure at 1,170 ° C. and changed to a hexagonal system at 2,300 ° C. When the phase change is changed from a monoclinic system to a tetragonal system, a grain change is accompanied by a volume change of about 5%, which is a fatal defect in the production of refractory materials.

These fatal defects are solved by adding Yttria (Y2O3), Cubic oxide, Calcia and Magnesia. Among them, the most commonly used additives are hexagonal system So that it is possible to manufacture a refractory which requires a high temperature because no volume change occurs.

However, ytria is the most costly production cost due to its high price. (Considering that zirconia is at US $ 8 / Kg in recent years, it is priced at US $ 100 / Kg. And the zirconia refractory is required to minimize the content of yttria and to prevent deformation even during rapid heating and quenching.

The present invention is to provide a refractory manufacturing apparatus for use in a sapphire single crystal growth furnace made of melt stabilized zirconia beads in which the yttria content is minimized as follows.

1) It is possible to reduce the amount of expensive yttria to 5 wt% and to reduce the time required for refractory production to 4 hours required for the melting without the need of the crystal growth time, thereby reducing the cost compared to the time using cubic zirconia will be.

2) Melting stabilized zirconia beads produced by high-pressure air injection are stacked on the side of the refractory forming unit in the process of tilting the melted zirconia to the side of the refractory forming unit. In the laminating process, unmelted melt stabilization Zirconia beads are naturally adhered to each other so that they are cooled down as they become bricks, so that it is possible to obtain a refractory of excellent quality which can reduce the cost considerably, is not dissolved during use, and does not spout gas.

3) When the molten zirconia with 5 wt% of yttria is rapidly cooled with high-pressure air, a large amount of hexagonal material can be obtained. When the thermal expansion coefficient is measured, it is confirmed that the phase transformation due to the temperature change is hardly observed So as to be applicable to the present invention (see FIG. 3 or FIG. 4).

4) Since there are many pores inside the refractory, the weight can be greatly reduced, and it is possible to manufacture by four large pieces, so that the material can be saved, and the effect of the insulation by the air gap can be improved (See FIG. 11).

5) It is for inserting the ultra-high temperature heat inside the sapphire single crystal growth through the air and performing the insulation.

6) Melt-stabilized zirconia beads containing 5 wt% or more of yttria - The above-mentioned 'melt-stabilized zirconia beads' are mostly made of hexagonal zirconia, and even if they have a structure other than some hexagonal structure, Beads) and have a constant pore, meaning that there is no problem in maintaining the basic structure of the refractory when the temperature changes - can be applied to a sapphire single crystal growth furnace with a temperature of up to 2,300 ° C .

7) The porosity of the refractory is maintained at 20% or more, so that the total material (yttria + zirconia) can be saved by 20% or more.

8) It is intended to make ideal refractories by maintaining the basic structure of the refractory even when the temperature is changed by allowing the zirconia to accumulate in a bead shape so that only a certain portion of the zirconia is adhered to each other.

9) As shown in FIG. 4, although slight phase transformation appears at a temperature of about 900 ° C., it is intended to prevent the refractory breakage by absorbing the phase transformation.

According to an aspect of the present invention, there is provided a refractory manufacturing apparatus for use in a sapphire single crystal growth furnace made of melt stabilized zirconia beads with minimized yttria content. A melting furnace which is rotatable in one direction on the support and melts zirconia containing yttria by a high frequency skull melting method; And a high-pressure air is injected toward the molten zirconia falling from the melting furnace so as to move the molten stabilized zirconia bead in the upward and downward directions and in the forward and backward directions in which the molten furnace rotates, A high pressure air injection unit to generate the high pressure air injection unit; And a molten stabilized zirconia bead disposed in a direction in which the molten furnace is tilted under the high-pressure air injection unit to form a refractory by laminating the molten stabilized zirconia beads, wherein the refractory comprises a plate-like pedestal and a cylindrical inner shaping frame And an external mold for forming a lamination space in which the melt-stabilized zirconia beads are spaced apart from the inner mold by a predetermined distance, the molten stabilized zirconia beads being stacked in the lamination space, A refractory forming unit provided with a rotary drive unit for transmitting rotary power; .

And the high-pressure air injection unit is provided so as to be movable in the upward and downward directions and in the forward and backward directions in which the melting furnace rotates.

The refractory forming unit includes a flat plate-like pedestal; A forming mold having a cylindrical inner forming mold provided at a predetermined height in the center of the pedestal and an outer forming mold spaced apart from the inner forming mold by a predetermined distance to form a lamination space in which molten stabilized zirconia beads are stacked; And a rotation drive unit for transmitting rotational power to the molding die so that the melt-stabilized zirconia beads stacked in the lamination space are rotated; And a control unit.

And the outer mold is detachably installed by a screw-type fastener.

And the refractory forming unit is of a dual type.

As described above, according to the refractory manufacturing apparatus used in the sapphire single crystal growth furnace made of the melt stabilized zirconia beads with minimized yttria content according to the present invention, the following effects can be produced.

1) By reducing the amount of expensive yttria to 5 wt% and reducing the time required for refractory production to 4 hours required for the melting process without the need for a crystal growth time, it is possible to reduce the cost compared to the time using cubic zirconia have.

2) Melting stabilized zirconia beads produced by high-pressure air injection are stacked on the side of the refractory forming unit in the process of tilting the melted zirconia to the side of the refractory forming unit. In the laminating process, unmelted melt stabilization Since the zirconia beads naturally adhere to each other and become a brick, cooling can be performed. Therefore, it is possible to obtain a high quality refractory material which can be reduced in cost, is not dissolved during use, and does not spout gas.

3) When the molten zirconia with 5 wt% of yttria is rapidly cooled with high-pressure air, a large amount of hexagonal material can be obtained. When the thermal expansion coefficient is measured, it is confirmed that the phase transformation due to the temperature change is hardly observed There is an effect that can be applied to the present invention (see FIG. 3 or FIG. 4).

4) Since there are many pores inside the refractory, the weight can be greatly reduced, and it is possible to manufacture four large pieces so that the material can be saved and the effect of improving the thermal effect by the air gap (See Fig. 11).

5) There is an effect that the super high temperature heat can be maintained inside the sapphire single crystal growth through the air and the insulation can be performed.

6) Melt-stabilized zirconia beads containing 5 wt% or more of yttria - The above-mentioned 'melt-stabilized zirconia beads' are mostly made of hexagonal zirconia, and even if they have a structure other than some hexagonal structure, Beads) and have a constant pore, meaning that there is no problem in maintaining the basic structure of the refractory when the temperature changes - can be applied to a sapphire single crystal growth furnace with a temperature of up to 2,300 ° C There is an effect.

7) Since the porosity of the refractory is maintained at 20% or more, the total material (yttria + zirconia) can be saved by 20% or more.

8) Since zirconia is accumulated in a bead shape and only a certain portion of the zirconia is adhered to each other, it has large pores, so that it is possible to manufacture an ideal refractory by maintaining the basic structure of the refractory even when the temperature changes.

9) As shown in FIG. 4, although slight phase transformation appears at a temperature of about 900 ° C., there is an effect of preventing breakage of the refractory by absorbing the phase transformation.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view showing a brick type refractory using cubic zirconia according to the prior art. FIG.
2 is a perspective view showing a refractory of large capacity made of cubic zirconia according to the prior art.
3 is a state diagram showing the state of zirconia containing yttria according to the present invention.
4 is a graph showing a thermal expansion state of zirconia under a temperature change according to the present invention.
FIG. 5 is a schematic structural view showing an apparatus for producing a melt-stabilized zirconia refractory according to the present invention.
FIG. 6 is a schematic perspective view showing an apparatus for producing a zircon oxide refractory according to the present invention.
7 is a perspective view showing a high-pressure air injection unit according to the present invention.
8 is a perspective view showing the moving state of the high-pressure air injection unit according to the present invention.
9 is a plan view showing a melter discharge port according to an example of the present invention.
10 is a plan view showing a discharge port of a melting furnace according to another example of the present invention.
11 is a perspective view showing refractories manufactured through the apparatus for producing a melt-stabilized zirconia refractory according to the present invention.
12 is a schematic view showing the voids of the melt-stabilized zirconia refractory according to the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. It is to be understood that the present invention may be embodied in many other specific forms and should not be construed as limited to the embodiments set forth herein. Rather, the same reference numbers are used throughout the drawings to refer to the same or like parts.

The present invention is based on finding out how a zirconia forming a refractory can maintain a cubic shape while lowering the use amount of expensive yttria. To this end, if zirconia melted in an amount of 5 to 8 wt% of yttria in the ZrO 2 -Y 2 O 3 phase can be maintained in a hexagonal system without being changed into a tetragonal structure, the melt stabilized zirconia beads B / Z) ". < / RTI >

When the temperature is gradually lowered, zirconia having an eutria content of 5 to 8 wt% is usually converted into a tetragonal structure and then converted to monoclinic at room temperature. Depending on the structure of each crystal, , Which causes zirconia to break down due to changes in temperature. At this time, the most important thing is the time required to meet the high-pressure air injected by the overflowing blast furnace solution, the time for the high-pressure air to be injected and beaded, and then accumulated in the refractory forming unit and the diameter of the bead, What works well is the most important thing.

According to an apparatus 100 for manufacturing a super low transformation forming zirconia refractory according to the present invention, zirconia refractory manufacturing apparatus 100 includes support base 110 and zirconia which is rotatable in one direction on support base 110, And a high-pressure air stream, which is located at a lower portion of the melting furnace 120 and injects high-pressure air toward the molten zirconia falling from the melting furnace 120, to generate molten stabilized zirconia beads, And a refractory forming unit 140 disposed below the high-pressure air injecting unit 130 and disposed in a direction in which the melting furnace is inclined to form molten stabilized zirconia beads to produce refractory.

The support base 110 is supported on the bottom surface to support the melting furnace 120 in a rotatable manner. The supporting frame 110 is made of a rectangular frame or the like and supports a melting furnace 120 positioned at a predetermined height in a vertical direction.

The melting furnace 120 serves to melt the zirconia added with yttria by a skull melting method using a high frequency so as to be rotatable in one direction on the support base 110.

Zirconia (zirconium oxide) melted through the melting furnace 120 is a white crystalline substance having a molecular weight of 123.22 and a melting point of about 2,700 ° C, which is a rare mineral in a monoclinic system. Since zirconia has a high refractive index and a high melting point, it is highly resistant to corrosion and does not dissolve in water, and is resistant to rapid temperature changes. Therefore, it is also used as an important raw material for a rapidly heating and quenching apparatus (for example, a melting furnace) and for ceramics. Zirconia is a monoclinic system at room temperature. It changes into a tetragonal structure at 1,170 ° C and causes a phase change that changes to a hexagonal system at 2,300 ° C. When zirconia is changed from a monoclinic system to a tetragonal system, a volume change of about 5% The particles are broken and act as fatal defects in the production process.

The yttria is used as a stabilizing material to be added to zirconia that is melted through the melting furnace 120 to prevent particles from breaking during the phase change process of zirconia as described above. The yttria is preferably added in a minimum amount of about 5 to 8 wt% based on the total wt% of zirconia. When the yttria is added in an amount of about 5 to 8 wt% based on the total wt% of zirconia, the refractory 150 can be manufactured without causing any volume change because the hexagonal system is maintained even when the temperature changes.

In addition to minimizing the content of yttria added to zirconia to about 5 to 8 wt%, various materials such as Cubic oxide, Calcia and Magnesia may be added to zirconia if the same conditions are satisfied in the phase diagram It is possible. Thus, the cost required can be greatly reduced.

The melting furnace 120 melts yttria added in an amount of about 5 to 8 wt% based on the total weight% of zirconia, and then rotates in one direction to perform the operation of dropping molten zirconia into the air (see arrow ⓐ in FIG. 5) ). A discharge port 122 for discharging fused zirconia is formed in the melting furnace 120. The discharge port 122 is formed in an inverted triangle or flat plate shape as shown in FIG. 9 or 10, It is preferable to form the zirconia so as to sink downward so as to facilitate falling.

As described above, it is preferable that the size of the melting furnace 120 for melting the yttria-added zirconia is 760 mm in diameter and 800 mm in height, and a high-frequency system is used for the melting method. It is preferable that the frequency is 45 kHz and the output power is 180 kW.

The high-pressure air injection unit 130 is located below the melting furnace 120 and injects high-pressure air toward the molten zirconia falling from the melting furnace 120 to generate melt stabilized zirconia beads (B / Z) Role.

For this purpose, the high-pressure air injection unit 130 allows air supplied through the air supply unit 132 to be injected toward the molten zirconia falling by using the air injection nozzle 134.

The high-pressure air injection unit 130 can be installed to be movable in the upward and downward directions by the cylinder 131 system in accordance with the installation environment or the quenching conditions of the molten zirconia. (Refer to the arrows b and c in Fig. 8). The high-pressure air injection unit 130 may be moved upward, downward, backward, and backward in various manners such as a method of moving the high-pressure air injection unit 130 through gears in addition to the cylinder 131 method.

The refractory forming unit 140 (FIG. 1) for determining the crystal structure of zirconia and forming the refractory 150 in the process of forming the molten zirconia into the melt stabilized zirconia bead (B / Z) by using the high-pressure air injection unit 130 (B / Z) to be laminated on the heat-resistant zirconia beads (B / Z) are bonded together without a separate adhesive.

In order to satisfy such a condition, it is necessary to quench the molten zirconia containing yttria. To this end, the distance between the melting furnace 120 and the high-pressure air injection unit 130 is set to 30 to 200 mm, It is preferable that the high-pressure air pressure injected from the high-pressure air injection unit 130 can be maintained at 5 to 30 kg / cm 2.

In addition, the diameter of the melt stabilized zirconia beads (B / Z) generated by the high-pressure air injected from the high-pressure air injection unit 130 is 0.2 to 7, more preferably 0.7 to 4.5, 1.5 to 3.0 ?. If the diameter of the melt-stabilized zirconia bead (B / Z) is formed to 7Φ or more, the hexagonal system is not maintained completely and the product is not properly formed. If the diameter is less than 0.2Φ, Can not be smoothly performed. The diameter of the melt stabilized zirconia beads differs depending on the air pressure and the size of the air holes, but generally tends to depend on the air pressure. With the apparatus of the present invention, the diameter of the beads is 3? On the average at a pressure of 7 kg / cm < 2 >, and in the case of 150 kg / cm < 2 >

The method of forming the molten zirconia to be dropped from the melt stabilized zirconia beads (B / Z) can remarkably reduce the production cost and can be applied to the entire molten zirconia to be dropped. Thus, almost all zirconia is converted into hexagonal system .

The refractory forming unit 140 is disposed below the high-pressure air injection unit 130 and is disposed in a direction in which the melting furnace 120 is tilted to form a refractory 150 by laminating molten stabilized zirconia beads (B / Z) .

The refractory forming unit 140 includes a pedestal 142, a forming frame 144 provided on the pedestal 142 and a rotation driving unit 146 for transmitting rotational power to the forming frame 144 .

The pedestal 142 is formed into a flat plate shape to support the inner forming mold 144a and the outer forming mold 144b constituting the forming mold 144 and the outer forming mold 144a and the outer forming mold 144b Stabilized zirconia beads (B / Z) to be laminated in the formed stacked space 144c.

The mold 144 includes a cylindrical inner mold 144a having a predetermined height at a central portion of the pedestal 142 and an outer mold 144a located outside the inner mold 144a, And an outer mold frame 144b for forming a lamination space 144c in which zirconia beads (B / Z) are laminated.

It is preferable that the outer mold frame 144b is detachably installed by a screwed fastener 144d. The refractory 150 formed in the laminated space 144c can be easily and conveniently moved to a desired position by separating the fastening piece 144d and peeling off the outer forming frame 144b. It is preferable that the upper end of the outer shaping mold 144b is provided with a collecting piece 144b-1 of a superfluous lower compartment so that the molten stabilized zirconia bead (B / Z) Do.

 The rotation drive unit 146 serves to transmit the rotational power to the mold frame 144 so that the melt-stabilized zirconia beads (B / Z) stacked in the laminate space 144c are rotated. The molding frame 144 that rotates by receiving the rotational power of the rotation driving unit 146 rotates for a predetermined period of time to produce the desired refractory 150 (see the direction of arrow D in FIG. 5).

The refractory forming unit 140 having the above-described structure can be variously implemented according to the installation and manufacturing conditions such as a dual type.

On the other hand, what is important in the present invention as much as the diameter of the melt stabilized zirconia beads (B / Z) is how much the melt stabilized zirconia beads (B / Z) are exposed to air and quenched. The present invention uses air as means for cooling melt stabilized zirconia beads (B / Z). Therefore, the time for which the melt-stabilized zirconia beads (B / Z) formed by high-pressure air injection is exposed to air is immediately quenched. From the state diagram, it is a core technology of the present invention that the zirconia is in a cubic state in which the temperature is slightly lowered in a molten state, and quenched to maintain the cubic state.

Thus, it is preferable that the distance for dropping the melt stabilized zirconia beads (B / Z) into the refractory forming unit 140 is 0.5 to 3 m as a condition for rapid quenching of the melt stabilized zirconia beads (B / Z). The falling distance of the melt-stabilized zirconia beads (B / Z) can be variously determined by those skilled in the art depending on the ambient conditions at which quenching occurs.

The method of forming the molten zirconia to be dropped by using the melt stabilized zirconia beads (B / Z) can remarkably reduce the production cost and can be applied to the entire molten zirconia to be dropped. It can be said to be effective.

According to the present invention, as shown in the state diagram of FIG. 3, when the content of yttria is 20% or less, a tetragonal structure is generally formed by cooling, and when the refractory 150 is formed, It is possible to dramatically improve the cause of breakage of the refractory because the change of the volume is caused by the change.

Further, since each of the melt-stabilized zirconia beads (B / Z) is adhered only to a certain portion, the air gap is increased to improve the heat insulating property, and a small amount of tetragonal or monoclinic system may be generated during the quenching Since the finally formed melt stabilized zirconia beads (B / Z) are capable of withstanding a volume difference due to temperature change without a significant effect as compared with when there is no air gap as the refractory 150 having a large air gap, It is possible to perform a role as a user.

It is noted that the refractories produced by the apparatus for manufacturing an ultralow-shaped zirconia refractory material with minimized yttria content according to the present invention are obtained through the respective examples as shown in the following table.

In each embodiment of the present invention, the size of the melting furnace 120 was 760 mm in diameter and 800 mm in height. At this time, the method of melting zirconia adopts a high frequency method, the frequency was 45 kHz, and the output power was 180 kW. The molten zirconia injected from the melting furnace was adjusted to 150 kg / hr.

In addition, the distance from the high-pressure air injection unit 130 to the bottom surface of the refractory forming unit 140 was maintained to be 1.5 m in principle. In this process, the distance from the high-pressure air injection unit 130 to the bottom of the refractory forming unit 140 has been variously carried out. However, since the melt-stabilized zirconia beads (B / Z) It was found that the adhesion between the melt-stabilized zirconia beads (B / Z) can be maintained constant.

Example Porosity (%) Size of center bead (mm) The air pressure of the nozzle (kg / cm2) Vertical distance from the nozzle to the nozzle (㎝) From nozzle inlet to molten zirconia
Horizontal distance (cm) One 16 2.5 10 5 5 2 20 2.8 10 10 5 3 28 4.5 8 10 10 4 10 1.2 20 10 5 5 12 2.0 20 10 10

(Examples 1 to 5)

As shown in Table 1, according to the refractory manufacturing apparatus used in the sapphire single crystal growth furnace made of the melt stabilized zirconia beads with minimized yttria content according to the present invention, the amount of yttria-added zirconia dropped in the melting furnace, Precise manufacturing conditions such as high-pressure air injection pressure and shape, average diameter of melt stabilized zirconia bead (B / Z), distance of melt-stabilized zirconia bead (B / Z) falling into refractory forming unit 140, It is very important.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the scope of the invention is not limited to the disclosed exemplary embodiments. As shown in FIG.

100: a zirconia refractory manufacturing apparatus, 110: a support,
120: melting furnace, 122: discharge port,
130: high-pressure air injection unit, 131: cylinder,
132: air supply part, 134: air jet nozzle,
140: refractory forming unit, 142: pedestal,
144: forming mold, 144a: inner forming mold,
144b: external molding frame, 144b-1: collecting piece,
144c: a lamination space, 144d: a fastening piece,
146: rotation drive unit, 150: refractory,
B / Z: melt stabilized zirconia beads.

Claims (5)

delete delete support fixture;
A melting furnace which is rotatable in one direction on the support and melts zirconia containing yttria by a high frequency skull melting method;
And a high-pressure air is injected toward the molten zirconia falling from the melting furnace so as to move the molten stabilized zirconia bead in the upward and downward directions and in the forward and backward directions in which the molten furnace rotates, A high pressure air injection unit to generate the high pressure air injection unit; And
And the molten stabilized zirconia beads are stacked in a direction in which the melting furnace is tilted under the high-pressure air injection unit to form a refractory, wherein the refractory is formed by a plate-like pedestal and a cylindrical inner forming mold provided at a predetermined height in the center of the pedestal A molding die made of an outer molding die which is spaced apart from the inner molding die by a predetermined distance to form a lamination space in which the melt-stabilized zirconia beads are laminated; and a rotary mold rotatably supported on the molding die so as to rotate the melt- A refractory forming unit provided with a rotary drive unit for transmitting power;
Wherein the molten stabilized zirconia beads have a minimized yttria content.
The method of claim 3,
Wherein the outer mold is removably installed by threaded fasteners. The apparatus for manufacturing a refractory for use in a sapphire single crystal growth furnace according to claim 1, wherein the molten stabilized zirconia beads have a minimum yttria content.
The method of claim 3,
Characterized in that the refractory forming unit is of a dual type. The apparatus for manufacturing a refractory for use in a sapphire single crystal growth furnace made of melt-stabilized zirconia beads with minimized yttria content.

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