JP2920084B2 - Ultra high pressure generator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultra-high pressure generator. More specifically, the present invention relates to an ultra-high pressure generator used for synthesizing diamond and cubic boron nitride and for testing the deformation characteristics of a substance under ultra-high pressure.

[0002]

2. Description of the Related Art In an ultrahigh pressure generator, there has been no example developed so far for testing the deformation characteristics of a substance under ultrahigh pressure. The conventional ultrahigh-pressure generators are all for synthesizing diamond or the like, but the following is a time series of the prior art having a structure similar to the present invention.

[0003] In general, devices for generating high pressure include a piston cylinder type and an anvil cylinder type.
In each case, an ultra-high pressure generation chamber is formed in the center, a pressure medium such as pyrophyllite is filled in the ultra-high pressure generation chamber, and the pressure medium is compressed by a pressurized anvil to generate an ultra-high pressure. . That is, as shown in FIG. 8, a conventional apparatus of this type surrounds a pressure medium 102 with a plurality of anvils 101 and
An ultra-high pressure generation chamber with a built-in 102
1 is pressed and pushed toward the center, thereby generating an ultra-high pressure. However, when the anvil 101 is pressed and pushed to move from the position shown by the solid line to the position shown by the dotted line, the pressure medium 102 is also compressed as shown by the dotted line from the solid line, and the pressure medium 102 A protruding portion (a) is formed, and if the anvil 101 is further pressed and pushed, this proceeds as shown by a dashed line diagram, and a protruding portion (b) of the pressure medium 102 is formed. The compression of the protruding parts (a) and (b) by the anvil 101 is the central pressure medium.
This ratio is much greater than the compression of 102, and the greater the anvil 101 is pushed to generate an ultra high pressure, the greater this ratio. Therefore, in the conventional apparatus shown in FIG.
The loss caused by the pressing force of 1 in the protruding portions (a) and (b) is extremely large, and the gap portion of the anvil 101 is considerably small, so that the formation of the protruding portion rapidly expands, and the loss increases rapidly. And the like.

[0004] The ultra-high pressure generator of Japanese Patent Publication No. 47-50258 (conventional example I) is designed to solve the above-mentioned disadvantages and is configured as shown in FIG. 201 is a pressurized anvil,
202 is a fixed anvil, 203 is a cylinder (anvil)
Then, a pressurized anvil 201 and a fixed anvil 202 are arranged above and below the cylinder 203 so as to face each other, and an ultra-high pressure generating chamber filled with a pressurized medium 204 such as pyrophyllite is formed by being surrounded by these. I have. Reference numeral 205 denotes a piston body, which has a pressing surface 205 'in the pressing surface 201' of the pressing anvil 201 and is provided substantially concentrically in the pressing anvil 201. 20
A plug 6 for forming a pressure cylinder of the piston body 205 is screwed to the pressure anvil 201. 207 is a pressure cylinder of the pressure anvil 201. As described above, in Conventional Example I, the pressurizing anvil 201 and the piston body 205 are provided, and the pressurizing anvil 201 first pressurizes to a predetermined position, and then pressurizes with the piston body 205. The pressure medium 204 that has overflowed under pressure is applied to the pressure anvil 20.
1 has the function of a gasket at the position where the pushing is stopped, and at the next pressurization by the piston body 205, only the central pressure medium 204 is continuously pressurized without expanding the protruding portion (a). To produce the desired ultra-high pressure. Therefore, the protruding portion of the pressure medium 4 is reduced, and a desired ultrahigh pressure can be obtained without increasing the pressure loss caused by compressing the protruding portion. By the way, as shown in FIG. 10, forces P1, P2 perpendicular to the top surfaces of the anvils 201, 202 and the wall surfaces of the outer conical surfaces act on the anvil of the ultrahigh pressure generator shown in FIGS. When the piston hole 206 for inserting the piston body 205 into the anvils 201 and 202 in such an external force field is formed larger than the outer diameter of the piston body 205, the anvils 201 and 202 are broken due to stress concentration on the piston holes. There is a defect that it will.

Therefore, in the prior art II described in Japanese Patent Application Laid-Open No. 54-21967, the piston hole diameter is set to be slightly smaller than or equal to the outer diameter of the piston body, and the piston body is pressed into this hole. I have. However, the above conventional example
In the case of II, if the pressures P1 and P2 acting during compression are different, as shown in FIG.
, 202 are deformed from the solid line as shown by the imaginary line, and the diameter of the piston hole 206 is reduced inward as indicated by the X portion. As a result, the piston body is restrained by the anvil. This means that when the ultra-high pressure generator is used for synthesizing diamond or the like, the loss of driving force increases,
The piston body and the anvil are easily broken, and furthermore, there is a disadvantage that the generated super-high pressure is insufficient.
In addition, if the ultra-high pressure generator is a device for testing the deformation characteristics under ultra-high pressure, in addition to the disadvantages described above, it is necessary for the deformation of the sample under ultra-high pressure due to the friction or binding force between the piston body and the piston hole. It appears as a fatal drawback that the force cannot be measured accurately.

[0006]

SUMMARY OF THE INVENTION In view of the foregoing, the present invention has low loss of piston driving force, is less likely to cause damage to the piston body and the anvil itself, is safe, can obtain a high compression pressure, and can provide a piston body with a high compression pressure. It is an object of the present invention to provide an ultra-high pressure generator capable of minimizing a frictional force and a restraining force with an acting piston hole and accurately detecting deformation data under an ultra-high pressure.

[0007]

According to the present invention, there is provided an ultra-high pressure generating apparatus, wherein an ultra-high pressure generating chamber for containing a substance is formed by being surrounded by a plurality of anvils. An ultra-high pressure generator having a piston hole formed therein, the piston body being moved to the ultra-high pressure generation chamber side by an external force into the piston hole, wherein the piston is inserted into a tip of an anvil into which the piston body is inserted. A conical concave portion concentric with the hole is formed, and is formed of a thin and soft material.The conical plate-shaped thin soft plate having a hole formed in the center thereof for penetrating the piston body. A mortar-shaped anvil tip member provided with a hole through which the piston body penetrates, and a conical small recess formed on the side of the ultrahigh-pressure generation chamber, wherein the thin soft plate and the anvil tip member are provided. , In that order Fitted into the conical recess, characterized in that it is interposed soft material between the small recesses and holes of the anvil tip member and the piston member. In the above invention, it is preferable that the hole of the anvil tip member has an inner diameter larger than the outer diameter of the piston body.

[0008]

According to the present invention, when pressurized, the anvil tip member is substantially surrounded by a soft substance and is in contact with the conical recess of the anvil through a thin soft plate, so that a uniform force is received from the anvil. Therefore, since the anvil tip member receives a compressive force on any surface, it becomes a hydrostatic stress field and is less likely to be damaged. The anvil also has a pseudohydrostatic stress field because the force received from the anvil tip member and the pressure acting on the outer cone of the tip part oppose each other and compress, so that damage is less likely to occur. further,
In the present invention, the frictional force or the restraining force acting on the piston body can be greatly reduced. That is, the anvil tip member is pushed into the conical recess of the anvil by the pressure at the time of pressurization and acts as a wedge. At this time, since the bottom conical surface of the anvil tip member and the inner conical surface of the conical concave portion of the anvil are inclined surfaces, the pushing force acts in a direction perpendicular to the inner conical surface, that is, in a direction to expand the piston hole. Since the force due to this wedge action opposes the force acting on the outer cone of the tip of the anvil,
The diameter of the piston hole formed at the center of the anvil can be reduced. Therefore, the frictional force acting on the piston body does not increase. Therefore, the loss of the piston driving force due to friction or the like is small, and the data relating to the deformation of the sample under ultra-high pressure can be accurately detected. When the hole of the anvil tip member is made larger than the outer diameter of the piston body, a soft substance also exists between the hole and the piston body, and the piston body slides against the soft substance, so that friction occurs. The force is further reduced and stable operation is possible. Therefore, more accurate deformation data can be detected.

[0009]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view showing an anvil structure of an ultra-high pressure generator according to one embodiment of the present invention, FIG. 2 is an exploded perspective view of an upper anvil structure of FIG. 1, and FIG. 3 explains advantages of the anvil structure according to the present invention. FIG. 4 is an overall view of the ultra-high pressure generator, and FIG.
Is a partial perspective view of the upper and lower anvils and side anvils.

First, the overall configuration of the ultra-high pressure generator is shown in FIGS.
Explaining based on 5, 1 is an upper anvil, 2 is a lower anvil, and each of the pair of upper and lower anvils 1 and 2 has a tapered truncated pyramid-shaped tip, and the end face of the tip is They are arranged to face each other. Reference numeral 3 denotes a side anvil disposed at an intermediate position between the anvils 1 and 2, similarly to the anvils 1 and 2, having a tapered quadrangular pyramid-shaped tip. The anvils 3 are disposed in the front, rear, left and right directions (the front side anvil is not shown in FIG. 5), and the object to be compressed is held between the end surfaces of the front end portions and the front end portions of the pair of upper and lower anvils 1 and 2. An ultra-high pressure generation chamber 4 which is a space to be inserted is formed. Reference numeral 5 denotes an upper ram for driving a piston body 8 described later, and reference numeral 6 denotes a lower ram for driving the lower anvil 2. The pair of anvils 1 and 2 and the pair of upper and lower rams 5 and 6 are coaxially attached to the press frame 7 with their centers aligned with the axis y. In addition, a piston hole is formed in one of the pair of anvils 1 and 2 and, in the illustrated example, in the upper anvil 1 concentrically with the axis y.
The piston body 8 is inserted. The side anvil 3 can pressurize the compressed object 45 put in the ultrahigh pressure generation chamber 4 by a pressurizing device such as a ram (not shown),
The lower anvil 2 is configured to move up and move toward the center by half of the amount moved by the ram 6.

The anvil structure of the upper anvil 1 having the piston body 8 will be described in detail with reference to FIGS. The tip of the anvil 1 is a truncated square pyramid with a flat tip.
It has a slope 11 and a head 12 of an outer conical surface. Also, the axis y
The piston hole 9 is formed concentrically with the piston hole 9, and a conical recess 13 is formed concentrically with the piston hole 9 so as to be dug down from the head 12. In the bottom of the conical recess 13, a diameter-reducing hole 14 concentric with the piston hole 9 is formed.

Reference numeral 20 denotes a thin soft plate, which is a thin conical plate made of a soft material such as lead. The thin soft plate 20 has a size along the inner conical surface of the conical recess 13, and a hole 21 through which the piston body 8 passes is formed at the bottom center. 30
Reference numeral denotes an anvil tip member, which is a thick-walled mortar made of the same hard metal or sintered diamond as the anvils 1 and 2. The anvil tip member 30 has a shape large enough to fit inside the thin soft plate 20, and a hole 31 having an inner diameter larger than the outer diameter of the piston body 8 is formed at the bottom center. On its upper surface, a conical small recess concentric with the hole 31 is provided.
32 are formed. And this anvil tip member 30
The outer conical surface 33 and the inner conical surface 34 are parallel.

The thin soft plate 20 and the anvil tip member 30 are
In that order, it is fitted into the conical recess 13 of the anvil 1. Then, with the piston body 8 penetrating the holes 31 and 21 of the anvil tip member 30 and the thin soft plate 20, the gap between the small recess 32 of the anvil tip member 30 and the piston body 8 and the hole 31 and the piston body 8
Is filled with a soft substance 40 such as lead.

The ultrahigh-pressure generator of the present invention described above uses a pair of upper and lower anvils 1 and 2
And then press the piston body 8 into the super high pressure state to synthesize diamond or cubic boron nitride, or to test the deformation characteristics of the substance when the piston body 8 enters. Can be In the material synthesis or deformation characteristic test as described above, the ultrahigh pressure generation chamber 4
When a substance to be pressurized 45 (sample) is put into the apparatus and pressurized by the anvils 1, 2 and 3, a force as shown in FIG. 1 acts on the anvil structure of the apparatus. That is, the force P1 acts vertically on the head 12 of the anvil 1, the top surface of the anvil tip member 30, and the soft substance 40 in the small recess 32, and the slope 11 of the anvil 1 and the anvil 3
The pressure medium will protrude into the slope of the anvil 1
A force P2 acts on 11 perpendicularly.

At this time, the following functions and effects are obtained based on the above structure. At the time of pressurization in the present apparatus, the anvil tip member 30 is substantially surrounded on the outer surface by the soft substance 40, and is in contact with the conical recess 13 of the anvil 1 through the thin soft plate 20, so that a uniform force is applied from the anvil 1 receive. Therefore, the anvil tip member 30 receives a compressive force on any surface, so that it becomes a hydrostatic stress field and is less likely to break. In addition, the distal end of the anvil 1 also becomes a quasi-hydrostatic stress field because the force received from the anvil distal member 30 and the pressure P2 acting on the slope 11 oppose each other and compress.
Breakage is less likely to occur.

Further, in the present device, the frictional force or restraining force acting on the piston body 8 can be greatly reduced. That is, the anvil tip member 30 is pushed into the conical recess 13 of the anvil 1 by the pressure at the time of pressurization, and acts as a wedge. At this time, since the bottom conical surface of the anvil tip member 30 and the inner conical surface 15 of the conical recess 13 of the anvil 1 are inclined surfaces, the pushing force P4 is perpendicular to the inner conical surface 15, as shown in FIG. It works in the direction of expanding the piston hole 9. The force P4 due to this wedge action is applied to the slope of the outer cone of the tip of the anvil 1.
Since it acts opposite to the force P2 acting on 11, the diameter of the piston hole 9 formed at the center of the anvil 1 can be reduced. Therefore, the frictional force acting on the piston body 8 does not increase. In addition, since the piston body 8 slides in contact with the soft substance 40 as shown in FIG. 1, the frictional force is further reduced, and stable operation is possible. Therefore, loss due to friction or the like of the piston driving force is small, and data required for deformation of the sample body under ultra-high pressure can be accurately detected.

Next, the procedure for testing the deformation characteristics under ultra-high pressure using this apparatus will be described with reference to FIG. First, a sample is placed in the ultrahigh-pressure generating chamber 4 of the cylinder 3 and the lower ram 2 is operated to generate a target ultrahigh pressure on the sample (see reference symbol a). Next, the pressure of the upper ram 5 is increased until the piston body 8 starts operating (see reference numeral b). Then, while maintaining the pressure of the upper ram 5 in the state at the time when the piston body 8 starts operating, the pressure reduction starts when the operation of the piston body 8 is stopped (see reference sign c). When the piston body 8 starts moving again (see the symbol d), the pressure reduction of the upper ram 5 is stopped and the pressure is maintained. Further, when the operation of the piston body 8 stops (symbol e)
The test is completed when the pressure of the lower ram 6 and the upper ram 5 is reduced.

If the pressures Pi and Pf required for the operation of the piston body 8 during this test are measured, the deformation resistance of the sample body under an extremely high pressure can be obtained. And the above pressures Pi, Pf
As described above, in the present apparatus, the friction and the restraining force generated when driving the piston body 8 are almost equal to zero, so that accurate measurement of the deformation characteristics with few errors becomes possible. When the above experiment is performed, the upper anvil 1 is kept at a high pressure when the piston body 8 is driven.
For the reasons described above, the anvil 1, the anvil tip 30 and the piston body 8 are not easily broken by the present apparatus.

Next, another embodiment of the present invention will be described.
In the above-described embodiment, the description has been given of the ultrahigh-pressure generating device constituted by the upper and lower anvils 1 and 2 and the four anvils 3. However, as shown in FIG. 7, a pair of upper and lower having a tapered frustoconical tip is provided. Hole 54 in the center between anvils 51 and 52
The present invention can also be applied to an ultra-high pressure generator provided with a hollow anvil (hollow cylinder) 53 having The hollow anvil (hollow cylinder) 53 is provided with upper and lower conical grooves corresponding to the truncated cone-shaped tips formed on the anvils 51 and 52. In short, the present invention relates to an ultrahigh-pressure generator having an ultrahigh-pressure generation chamber for storing a substance surrounded by a plurality of anvils, wherein a piston hole is formed in one of the anvils, and a piston body is inserted into the hole. A conical recess is formed at the end of the piston hole on the side of the ultrahigh pressure generation chamber, and a thin soft plate 20, an anvil tip member 30, and a soft substance 40 are interposed in the conical recess. I just need to.

[0020]

According to the present invention, the loss of the piston driving force is small, the piston and the anvil are less likely to be destroyed, the piston and the anvil are safe, a high compression pressure is obtained, and the frictional force and the restraint with the anvil acting on the piston are obtained. The force can be reduced as much as possible, and the deformation data under ultra-high pressure can be detected with high accuracy.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an anvil structure of an ultra-high pressure generator according to one embodiment of the present invention.

FIG. 2 is an exploded perspective view of the anvil structure of FIG.

FIG. 3 is an explanatory view of an advantage of the anvil structure according to the present invention.

FIG. 4 is an overall view of an extra-high pressure generator.

FIG. 5 is a perspective view of the anvil structure of FIG. 4;

FIG. 6 is an explanatory diagram of a procedure of a deformation characteristic test under ultra-high pressure.

FIG. 7 is a perspective view of an anvil structure of an ultra-high pressure generator according to another embodiment of the present invention.

FIG. 8 is an explanatory diagram of a problem of the related art using an anvil having no piston.

FIG. 9 shows a prior art I using an anvil having a piston.
FIG.

FIG. 10 is an explanatory diagram of a force acting on the anvil structure of the conventional technology I of FIG. 7;

FIG. 11 is an explanatory diagram of a problem of the prior art I of FIG. 7;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Upper anvil 2 Lower anvil 3 Side anvil 4 Ultra high pressure generating chamber 5 Upper ram 6 Lower ram 8 Piston body 9 Piston hole 11 Slope section 20 Thin soft plate 30 Anvil tip member 40 Soft material

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ identification code FI G01N 3/08 G01N 3/08 19/00 19/00 Z (58) Fields investigated (Int.Cl. ⁶ , DB name) B01J 3/06 G01N 3/00-3/62 C30B 28/00-35/00

Claims (2)

(57) [Claims] An ultrahigh pressure generation chamber for containing a substance surrounded by a plurality of anvils is formed, a piston hole is formed in one of the anvils toward the ultrahigh pressure generation chamber, and an external force is applied to the piston hole. An ultra-high pressure generating apparatus, wherein a piston body moved toward the ultra-high pressure generation chamber side is inserted, wherein a conical recess concentric with the piston hole is formed at the tip of the anvil into which the piston body has been inserted, and a thin wall is formed. And made of a soft material, a conical plate-shaped thin soft plate having a hole formed at the center thereof and a hole through which the piston body is formed, and a thick wall having a hole formed at the center thereof and penetrating the piston body, A mortar-shaped anvil tip member having a conical small recess formed on the side surface of the ultrahigh pressure generation chamber is provided, and the thin soft plate and the anvil tip member are inserted into the conical recess in this order. Of the anvil tip Ultra high pressure generating apparatus, characterized in that it is interposed soft material between the recesses and holes with the piston body. 2. The ultra-high pressure generator according to claim 1, wherein the hole of the anvil tip member has an inner diameter larger than the outer diameter of the piston body.