JPH09278580A - Production of crucible for growing single crystal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a crucible for growing a single crystal by which wrinkled are not formed in a V-shaped bottom; the crucible of a uniform thickness can be obtained; the number of welded parts is small; the quality is improved and the number of steps is reduced to improve both the production efficiency and appearance. SOLUTION: A mandrel 24 having the tip outer peripheral surface 23 formed into a funnel shape is held and fixed to a chuck part 22 of a rotator and a pipe 21 prepared by rolling a platy material of platinum or a platinum alloy and welding the lateral edges is engaged and held with the mandrel 24. A movable mandrel 26 having the tip outer peripheral surface 25 formed into the funnel shape is fitted into the pipe 21 oppositely to the mandrel 24 so as to enable the advance and retreat. The pipe 26 is pressurized with a spring 27 and the area reduction is carried out along the tip outer peripheral surface 23 of the funnel shape of the mandrel 24 with a roller 32 to afford a crucible 33.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a single crystal growing crucible made of platinum or a platinum alloy used for growing a ferrite single crystal.

[0002]

2. Description of the Related Art As is well known, a ferrite used for a tape recorder, a head of a video deck, or the like needs to be a ferrite single crystal. Ferrite single crystal is obtained by putting ferrite oxide powder in a crucible and dissolving it, and growing it.The material of the crucible for growing ferrite single crystal is chemically stable and is resistant to acid and alkali. Strong platinum and platinum alloys are used. Put ferrite oxide powder in this platinum or platinum alloy crucible,
In order to obtain a predetermined single crystal, it is necessary to heat to a temperature near the melting point of platinum or a platinum alloy, that is, a high temperature of 1600 to 1700 ° C. for several days.

As described above, a crucible for growing a ferrite single crystal made of platinum or a platinum alloy, which is used at a high temperature of 1600 to 1700 ° C. for several days, generally has a V-shaped bottom.

Conventionally, in order to manufacture this crucible for growing a single crystal, it is divided into a cylindrical portion, a conical portion, and a tip portion.
As shown in c, the materials 1, 2 and 3 of these parts are cut into a desired shape by cutting a plate material of platinum or a platinum alloy, and then these materials 1, 2 and 3 are respectively rounded to form end portions. Welded figure
As shown in 12 a, b and c, a cylindrical portion 4, a conical portion 5 and a tip portion 6 are made, and then these are welded as shown in FIG. 13 to assemble a crucible 7, and then the crucible 7 is drawn. The surface of the roller 8 is shaped as shown in FIG. 14 and finished as shown in FIG.

However, in this method, as shown in FIG. 13, the number of welded stitches 9 is increased and the quality is deteriorated. In addition, the number of processes is large, the manufacturing efficiency is poor, and the appearance is bad.

As another method for producing a crucible for growing a single crystal, a platinum or platinum alloy plate material 10 shown in FIG. 16 is rolled into a cylindrical shape as shown in FIG.
A method of narrowing one end of the to a V shape as shown in Fig. 18 was also considered, but when actually tested, the narrowed part
12 was wrinkled, and the plate pressure varied, and we couldn't manufacture it well.

[0007]

Therefore, the present invention reduces the number of welding stitches to improve the quality, reduces the number of steps to improve the manufacturing efficiency, and further improves the appearance.
An object of the present invention is to provide a method for manufacturing a crucible for growing a single crystal, which can eliminate variations in plate thickness.

[0008]

One of the methods for producing a crucible for growing a single crystal of the present invention for solving the above-mentioned problems is to prepare a pipe by rolling a plate material of platinum or a platinum alloy and welding the side ends to form a pipe. In a method for producing a crucible for growing a single crystal in which a roller is squeezed by a rotary processing machine, a funnel-shaped core metal having a tip outer peripheral surface is held and fixed to a chuck of the rotary processing machine, and the pipe is attached to the core metal. Is fitted and held, and a movable cored bar having a funnel-shaped tip end outer peripheral surface is inserted into the pipe so as to face the cored bar so as to be able to advance and retreat, and is pressed by a spring to form a funnel-shaped core of the cored bar. It is characterized in that a crucible for growing a single crystal is obtained by squeezing a pipe along the outer peripheral surface of the tip portion with a roller.

Another method of manufacturing a crucible for growing a single crystal according to the present invention is to grow a single crystal by rolling a plate material of platinum or a platinum alloy, welding the side ends to form a pipe, and then performing roller drawing by drawing. In the method of manufacturing a crucible for use, a core metal having a funnel-shaped outer peripheral surface is held and fixed to a chuck of a rotary processing machine, and a pipe having a pipe length of two crucibles is fitted to the core metal. While holding it, a movable cored bar having a funnel-shaped outer peripheral surface is fitted inside the pipe so as to face the cored bar, and is pushed forward and backward by pressing a spring, and the outer peripheral part of the funnel-shaped cored part of the cored bar is pressed. Roll the pipe along the surface and along the outer peripheral surface of the funnel-shaped tip of the moving core, and then cut the middle of the roller squeezed portion of the pipe to form two crucibles for growing single crystals. It is characterized by obtaining.

Method 2 for producing the above-mentioned crucible for growing a single crystal
In both cases, the moving cored bar, which faces the cored bar attached to the chuck of the rotary processing machine, is pressed toward the cored bar side by the spring and can be moved back and forth. When squeezing the rollers along the outer circumference of the tip,
The moving core bar retracts. Therefore, the material escaped by the roller squeeze is not restricted and is free, so that there is no wrinkle in the squeeze portion and a crucible for growing a single crystal having a uniform plate thickness can be obtained.

[0011]

[Example] 1 of manufacturing method of crucible for growing single crystal of the present invention
One embodiment will be described with reference to the drawings. Length 227m shown in Fig. 1
As shown in FIG. 2, a platinum plate 20 having an m, a width of 150 mm and a thickness of 0.4 mm was rolled and the side ends were welded to form a pipe 21 having an outer diameter of 73 mm. Next, a rotating machine such as a spinning machine, a lathe, a squeezing machine, and in the case of this example, a chuck 22 shown in FIG. 3 of the lathe is held and fixed to a core metal 24 having a funnel-shaped tip outer peripheral surface 23.
The pipe 21 was fitted and held on the core metal 24. Next, facing the core metal 24, a movable core metal 26 having a funnel-shaped distal end outer peripheral surface 25 is fitted in the pipe 21 so as to be able to move forward and backward, and a spring 27 is applied to the core metal 24 side from the rear end. Pressed. A rod 28 provided at the center of the rear end surface of the movable core 26 is slidably fitted in a hole 30 at the center of a fixed core 29 supported by a core pushing shaft (not shown), and the spring 27 is moved by the movable core 26. And fixed cored bar 29
It is fitted on the outer circumference of the rod 28 between and. A roller 32 for drawing was set on the tool rest 31 of the lathe. After that, the pipe 21 on the core metal 24 held and fixed to the chuck 22 is rotated together with the main shaft, and the pipe 21 is moved to the outer peripheral surface 23 of the funnel shape of the core metal 24 by the roller 32 as shown in FIG. Roller squeezing was performed along the same, and finally roller squeezing was performed until the moving cored bar 26 retracted to the outside of the pipe 21 as shown in FIG.

The single crystal growing crucible 33 thus obtained
When the V bottom portion 34 is squeezed by the roller, the moving cored bar 26 retreats, so that the material escaped by the roller squeeze is not restricted and is free. Therefore,
The V bottom portion 34 has a uniform plate thickness without wrinkling.

Next, another embodiment of the method for producing a crucible for growing a single crystal according to the present invention will be described with reference to the drawings. Platinum rhodium plate with a length of 159 mm, width of 310 mm, and thickness of 0.4 mm shown in Fig. 2
As shown in Fig. 7, round the 0'and weld the side edges to obtain an outer diameter of φ50m.
I made a pipe 21 'with a length of 2 crucibles in m. Next, attach the chuck 22 shown in FIG.
A funnel-shaped mandrel 24 was held and fixed, and the pipe 21 'was fitted and held on the mandrel 24. Then the core metal 24
A movable cored bar 26 having a funnel-shaped distal end outer peripheral surface 25 was fitted in the pipe 21 'so as to be retractable, and a spring 27 applied a pressure from the rear end toward the cored bar 24 side. A rod 28 provided at the center of the rear end face of the moving cored bar 26 is slidably fitted in a hole 30 at the center of a fixed cored bar 29 supported by a core pushing shaft (not shown),
The spring 27 is fitted around the rod 28 between the moving cored bar 26 and the fixed cored bar 29. A roller 32 for drawing was set on the tool rest 31 of the lathe.

Next, the pipe 21 'on the cored bar 24, which is held and fixed to the chuck 22 together with the main shaft, is rotated and, as shown in FIG. Along with 23, the roller is squeezed along the outer peripheral surface 25 of the funnel shape of the moving cored bar 26, and then the pipe 21 ′ is removed from the cored bar 24 and the movable cored bar 26, and the middle of the roller squeezed part Was cut as shown in FIG. 10 to obtain two crucibles 33 for growing a single crystal.

The two single crystal growing crucibles 33 thus obtained
When the V-bottom portion 34 is squeezed by the roller, the moving cored bar 26 retreats, so that the material escaped by the roller squeezing is not restricted and is free. Therefore,
The V bottom portion 34 has a uniform plate thickness without wrinkling.

[0016]

As can be seen from the above description, according to the method for producing a crucible for growing a single crystal of the present invention, the moving cored bar retreats when the roller forming the V-bottom is drawn, so that it escapes by the roller drawing. The material is unconstrained and free, thus providing a crucible of uniform thickness without wrinkling in the V-bottom portion. Further, compared with the conventional method of manufacturing a crucible for growing a single crystal, the number of welding points is significantly reduced, the quality is improved, the number of steps is reduced, the manufacturing efficiency is improved, and the appearance is improved.

[Brief description of drawings]

FIG. 1 is a diagram showing one first step of the method for producing a crucible for growing a single crystal according to the present invention.

FIG. 2 is a diagram showing one second step of the method for manufacturing a crucible for growing a single crystal according to the present invention.

FIG. 3 is a diagram showing one third step of the method for manufacturing a crucible for growing a single crystal according to the present invention.

FIG. 4 is a diagram showing a fourth step of the method for producing a crucible for growing a single crystal according to the present invention.

FIG. 5 is a diagram showing a fifth step of the method for producing a crucible for growing a single crystal according to the present invention.

FIG. 6 is a diagram showing another first step of the method for producing a crucible for growing a single crystal according to the present invention.

FIG. 7 is a diagram showing another second step of the method for producing a crucible for growing a single crystal according to the present invention.

FIG. 8 is a diagram showing another third step of the method for manufacturing a crucible for growing a single crystal according to the present invention.

FIG. 9 is a diagram showing another fourth step of the method for producing a crucible for growing a single crystal according to the present invention.

FIG. 10 is a diagram showing another fifth step of the method for manufacturing the crucible for growing a single crystal according to the present invention.

FIG. 11 is a diagram showing one first step of a conventional method for producing a crucible for growing a single crystal.

FIG. 12 is a diagram showing a second step of a conventional method for manufacturing a crucible for growing a single crystal.

FIG. 13 is a diagram showing one third step of the conventional method for manufacturing a crucible for growing a single crystal.

FIG. 14 is a diagram showing a fourth step of a conventional method for manufacturing a crucible for growing a single crystal.

FIG. 15 is a diagram showing one fifth step of the conventional method for producing a crucible for growing a single crystal.

FIG. 16 is another one of the conventional methods for manufacturing a crucible for growing a single crystal.
It is a figure which shows one 1st process.

[FIG. 17] Another method of manufacturing a conventional crucible for growing a single crystal
It is a figure which shows two 2nd processes.

[FIG. 18] Another method of manufacturing a conventional crucible for growing a single crystal
It is a figure which shows one 3rd process.

[Explanation of symbols]

 20 Platinum plate 20 'Platinum Rhodium plate 21 Pipe 21' Double length pipe 22 Chuck 23, 25 Tip outer peripheral surface 24 Core metal 26 Moving core metal 27 Spring 28 Rod 29 Fixed core metal 30 Hole 31 Turret 32 Roller 33 Single Crucible for crystal growth 34 V Bottom part

Claims (2)

[Claims] 1. A method for manufacturing a crucible for growing a single crystal, which comprises rolling a plate material of platinum or a platinum alloy, welding side ends thereof to form a pipe, and then performing roller drawing by a rotary processing machine. The outer peripheral surface of the tip is held and fixed by a funnel-shaped core, the pipe is fitted and held on the core, and the outer peripheral surface of the tip is funnel-shaped in the pipe facing the core. A single crystal characterized by obtaining a crucible for growing a single crystal by press-fitting a core bar so that the core bar can be advanced and retracted and pressing the pipe along the outer peripheral surface of the funnel shape of the core bar. Method for manufacturing crucible for growing. 2. A method for manufacturing a crucible for growing a single crystal, which comprises rolling a plate material of platinum or a platinum alloy, welding side ends thereof to form a pipe, and then performing roller squeezing with a rotary processing machine. A funnel-shaped mandrel is held and fixed on the outer peripheral surface of the tip, and a pipe having a length of two crucibles is fitted and held on the mandrel. A funnel-shaped moving core having an outer peripheral surface is fitted in such a manner that the movable core can be moved forward and backward, and is pressed by a spring, followed by the funnel-shaped tip of the core, and the funnel-shaped tip of the movable core continuously. A method for producing a crucible for growing a single crystal, which comprises squeezing a pipe along an outer peripheral surface and then cutting the middle of a squeezed portion of the roller of the pipe to obtain two crucibles for growing a single crystal.