JPH08229383A - Extra-high pressure generator - Google Patents

Abstract

PURPOSE: To suppress the breakage of the piston and anvil, to minimize the frictional force between the piston and piston hole acting on the piston and to detect the deformation data under extra-high pressure with high precision. CONSTITUTION: A conical recess 13 is formed at the tip of an anvil 1 into which a piston 8 is inserted. A conical thin soft sheet 20 and a conical anvil tip member 30 with a conical small recess 32 formed on its upper face are inserted in this order into the recess 13, and a soft substance 40 such as lead is interposed in the small recess 32 of the member 30 and between a hole 31 and the piston 8. The pseudo-hydrostatic pressure of condensed water acts on the piston and anvil to prevent them from being broken, the seduction in the diameter of a piston hole 9 is reduced by the wedge effect of the tip member 30, the frictional force is lowered, and the deformation data are precisely detected.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an ultrahigh pressure generator. More specifically, the present invention relates to an ultrahigh pressure generator used for synthesizing diamond and cubic boron nitride, and for testing the deformation characteristics of substances under ultrahigh pressure.

[0002]

2. Description of the Related Art In an ultrahigh pressure generator, there has been no example ever developed as an apparatus for testing the deformation characteristics of a substance under ultrahigh pressure. All of the conventional ultrahigh pressure generators are for synthesizing diamond and the like, and the following is a time series of conventional techniques having a structure similar to that of the present invention.

Generally, there are piston cylinder type and anvil cylinder type devices for generating high pressure.
In each case, an ultrahigh pressure generation chamber is formed in the center, a pressure medium such as pyrophyllite is filled in the ultrahigh pressure generation chamber, and the pressure medium is compressed by a pressure anvil to generate ultrahigh pressure. . That is, as shown in FIG. 8, the conventional device of this type has a plurality of anvils 101 surrounding the pressure medium 102.
An ultra high pressure generating chamber containing 102 is formed and
The pressure is pushed toward the center of 1 to generate ultra high pressure. However, when the anvil 101 is pushed forward and moved from the position shown by the solid line to the position shown by the dotted line, the pressure medium 102 is also compressed from the solid line as shown by the dotted line, and the pressure medium 102 in the gap portion of the anvil 101. If a protruding portion (a) is formed and the anvil 101 is further pushed under pressure, this advances as shown by the one-dot chain line, and the 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 pressure medium in the center.
It is considerably larger than the compression of 102, and the more the anvil 101 is pushed in order to generate an ultrahigh pressure, the larger this ratio becomes. Therefore, in the conventional device shown in FIG.
The pressure of 1 consumes a large amount of loss in the protruding portions (a) and (b), and the gap of the anvil 101 is considerably small, so the formation of the protruding portion spreads rapidly, and the loss increases rapidly. There were drawbacks such as.

The ultra-high pressure generator (Japanese Patent Publication No. 47-50258) (conventional example I) is intended to solve the above-mentioned drawbacks and is constructed as shown in FIG. 201 is a pressure anvil,
202 is a fixed anvil, 203 is a cylinder (anvil)
Then, the pressure anvil 201 and the fixed anvil 202 are arranged facing each other above and below the cylinder 203, and surrounded by these, an ultrahigh pressure generating chamber filled with a pressure medium 204 such as pyrophyllite is formed. There is. Reference numeral 205 denotes a piston body, which has a pressure surface 205 ′ in a pressure surface 201 ′ of the pressure anvil 201, and is disposed substantially concentrically in the pressure anvil 201. 20
Reference numeral 6 denotes a plug for forming a pressure cylinder of the piston body 205, which 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. First, the pressurizing anvil 201 pressurizes to a predetermined position, and then the piston body 205 pressurizes. The pressure medium 204 protruding by the pressure is the pressure anvil 20.
1 has the function of a gasket at the position where pushing is stopped, and the next time the piston body 205 pressurizes, only the central pressure medium 204 can continue to be pressurized without expanding the protruding part (a). , Will generate the desired ultra high pressure. Therefore, the protruding portion of the pressure medium 4 is reduced, and the desired ultrahigh pressure can be obtained without increasing the pressure loss due to the compression of the protruding portion. By the way, as shown in FIG. 10, forces P1 and P2 perpendicular to the top surfaces of the anvils 201 and 202 and the outer conical wall 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 machined larger than the outer diameter of the piston body 205, stress concentration on the piston holes causes the anvils 201 and 202 to break. There is a defect that it ends up.

Therefore, in the conventional example II described in JP-A-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 press-fitted into this hole. There is. However, the above conventional example
In the case of II, when the pressures P1 and P2 that act at the time of compression are different, as shown in FIG.
, 202 is deformed from the solid line state as shown by the imaginary line, and the piston hole 206 is reduced in diameter like the X portion, and as a result, the piston body is restrained by the anvil. This means that if the ultra-high pressure generator is for synthesizing diamond, etc., the loss of driving force will increase,
The piston body and the anvil are easily broken, and the disadvantage is that the ultra-high pressure generated is insufficient.
If the ultra-high pressure generator is a test device for deformation characteristics under ultra-high pressure, in addition to the above disadvantages, it is necessary to deform the sample body under ultra-high pressure due to friction or binding force between the piston body and piston hole. It appears as a fatal defect that the force cannot be measured accurately.

[0006]

In view of such circumstances, the present invention has a small loss of piston driving force, is less likely to cause damage to the piston body or the anvil itself, is safe, and has a high compression pressure. It is an object of the present invention to provide an ultra-high pressure generator capable of accurately detecting deformation data under ultra-high pressure by reducing frictional force and restraining force with an acting piston hole as much as possible.

[0007]

The ultrahigh pressure generator of the present invention forms an ultrahigh pressure generating chamber which is surrounded by a plurality of anvils and stores a substance, and one of the anvils is provided with the ultrahigh pressure generating chamber. An ultra-high pressure generator having a piston hole formed in the opposite direction, the piston body being moved to the ultra-high pressure generating chamber side by an external force is inserted into the piston hole, wherein the piston body is inserted at the tip of the anvil. A conical plate-shaped thin soft plate that has a conical recess that is concentric with the hole and that is thin and made of a soft material and that has a hole for penetrating the piston body in its center, and a thick center A hole for penetrating the piston body is formed, and a mortar-shaped anvil tip member having a conical small concave portion formed on the side surface of the ultrahigh pressure generating chamber is provided, and 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]

In the present invention, when the anvil tip member is pressurized, the outer surface of the anvil member is substantially surrounded by the soft material and is in contact with the conical concave portion of the anvil through the 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. Further, in the anvil as well, the force received from the tip member of the anvil and the pressure acting on the outer conical surface of the tip portion oppose and compress each other, so that a pseudo-hydrostatic stress field is generated, and breakage hardly occurs. further,
In the present invention, the frictional force or restraint force acting on the piston body can be greatly reduced. That is, the anvil tip member is pushed into the conical concave portion of the anvil by the pressure applied 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 the direction of expanding the piston hole. Since the force of this wedge action opposes the force acting on the outer conical surface of the tip of the anvil,
It is possible to reduce the diameter reduction of the piston hole formed in the center of the anvil. Therefore, the frictional force acting on the piston body does not increase. Therefore, there is little loss of the piston driving force due to friction and the like, and it is possible to accurately detect the data regarding the deformation of the sample body under an ultrahigh pressure. When the hole of the anvil tip member is made larger than the outer diameter of the piston body, soft material also exists between the hole and the piston body, and the piston body slides against the soft material, causing friction. The force is further reduced and stable operation is possible. Therefore, more accurate deformation data can be detected.

[0009]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is a sectional view showing an anvil structure of an ultrahigh pressure generator according to an embodiment of the present invention, FIG. 2 is an exploded perspective view of an upper anvil structure of FIG. 1, and FIG. 3 is an explanation of advantages of the anvil structure of the present invention. Fig. 4, Fig. 4 is an overall view of the ultrahigh pressure generator, Fig. 5
FIG. 3 is a partial perspective view of the upper and lower anvils and the side anvil.

First, FIG. 4 to FIG.
5, the upper anvil 2 and the lower anvil 1 have a pair of upper and lower anvils 1 and 2 each having a tapered truncated pyramid-shaped tip, and the end face of the tip is It is arranged to face each other. Reference numeral 3 denotes a side anvil disposed at an intermediate position between the anvils 1 and 2 and, like the anvils 1 and 2, has a tapered quadrangular truncated pyramid-shaped tip portion. The anvils 3 are arranged in front, back, left and right (the front side anvils are not shown in FIG. 5), and the end faces of the tip portions thereof and the end faces of the tip portions of the pair of upper and lower anvils 1 and 2 serve to compress the object to be compressed. An ultrahigh pressure generation chamber 4 which is a space for entering is formed. Reference numeral 5 is an upper ram for driving a piston body 8 described later, and 6 is a lower ram for driving the lower anvil 2. The pair of anvils 1, 2 and the pair of upper and lower rams 5, 6 are coaxially attached to the press frame 7 with their centers aligned with the axis y. Further, one of the pair of anvils 1 and 2, in the illustrated example, a piston hole is formed in the upper anvil 1 concentrically with the axis y,
The piston body 8 is inserted. The side anvil 3 can pressurize the object to be compressed 45 placed in the ultrahigh pressure generating 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 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 pyramid with a flat tip,
It has an outer conical slope 11 and a head 12. Also, the axis y
The piston hole 9 is bored concentrically with, and a conical recess 13 is formed concentrically with the piston hole 9 so as to be dug down from the head 12. Further, a reduced diameter hole portion 14 concentric with the piston hole 9 is formed in the bottom portion of the conical concave portion 13.

Reference numeral 20 is 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 concave portion 13, and a hole 21 through which the piston body 8 is inserted is formed at the center of the bottom portion thereof. 30
Is an anvil tip member, which is a thick-walled mortar body made of cemented carbide, sintered diamond, or the like similar to the anvils 1 and 2. The anvil tip member 30 has a size that fits 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 center of the bottom portion thereof. In addition, on its upper surface, a small conical recess concentric with the hole 31.
32 are formed. And this anvil tip member 30
The outer conical surface 33 and the inner conical surface 34 of are parallel to each other.

The thin soft plate 20 and the anvil tip member 30 are
The cone-shaped recess 13 of the anvil 1 is fitted in that order. Then, with the piston body 8 penetrated through the anvil tip member 30 and the holes 31, 21 of the thin soft plate 20, between the small recess 32 of the anvil tip member 30 and the piston body 8 and between the hole 31 and the piston body 8.
A soft substance 40 such as lead is packed between and.

In the ultrahigh pressure generator of the present invention described above, the substance in the ultrahigh pressure generating chamber 4 is placed in a pair of upper and lower anvils 1, 2.
It is used to synthesize diamond, cubic boron nitride, etc., or to test the deformation characteristics of the substance when the piston body 8 is rushed, To be In the material synthesis or deformation characteristic test as described above, the ultra high pressure generation chamber 4
When the substance 45 (sample) to be pressurized is put into the and is pressurized with the anvils 1, 2 and 3, a force as shown in FIG. 1 acts on the anvil structure of this device. 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 material 40 in the small recess 32, and the slope portion 11 of the anvil 1 and the anvil 3
The pressure medium will squeeze out into the slope of the anvil 1.
Force P2 acts on 11 perpendicularly.

At this time, the following operational effects are obtained based on the above structure. At the time of pressurization in this device, the anvil tip member 30 is substantially surrounded on its outer surface by the soft substance 40, and is in contact with the conical recess 13 of the anvil 1 via the thin soft plate 20, so that a uniform force is applied from the anvil 1 to the anvil 1. receive. Therefore, since the anvil tip member 30 receives a compressive force on any surface, it becomes a hydrostatic stress field and is less likely to be damaged. In addition, since the force received from the anvil tip member 30 and the pressure P2 acting on the slope portion 11 oppose and compress each other at the tip of the anvil 1, a pseudo hydrostatic stress field is obtained.
Less likely to be damaged.

Further, in this apparatus, the frictional force or the 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 applied 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 to widen the piston hole 9. The force P4 due to this wedge action is the slope portion which is the outer conical surface of the tip of the anvil 1.
Since it acts against the force P2 acting on 11, it is possible to reduce the diameter reduction of the piston hole 9 formed in the center of the anvil 1. Therefore, the frictional force acting on the piston body 8 does not increase. Further, as shown in FIG. 1, the piston body 8 slides in contact with the soft substance 40, so that the frictional force is further reduced and stable operation is possible. Therefore, there is little loss due to friction of the piston driving force, and the data required for the deformation of the sample body under ultrahigh pressure can be accurately detected.

Next, the test procedure of the deformation characteristics under the super high pressure by this apparatus will be described with reference to FIG. First, the sample body is put in the ultra-high pressure generation chamber 4 of the cylinder 3, and the lower ram 2 is operated to generate the target ultra-high pressure in the sample body (see symbol a). Next, the pressure of the upper ram 5 is increased until the piston body 8 starts to operate (see symbol b). Then, while the pressure of the upper ram 5 is maintained in the state at the time when the piston body 8 starts to operate, when the operation of the piston body 8 stops (see the reference sign c), decompression starts conversely. When the piston body 8 starts to move again (see reference numeral 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 is stopped (reference numeral e
Then, the pressure of the lower ram 6 and the upper ram 5 is reduced, and the test is completed.

By measuring the pressures Pi and Pf required for the operation of the piston body 8 during this test, the deformation resistance of the sample body under ultrahigh pressure can be obtained. And the above pressures Pi, Pf
In this measurement, since the frictional force and the restraining force generated when the piston body 8 is driven are substantially equal to zero as described above in this device, it is possible to accurately measure the deformation characteristic with less error. Further, in the case of performing the above experiment, the upper anvil 1 maintains a high pressure when the piston body 8 is driven,
For the above reasons, the anvil 1, the anvil tip portion 30, and the piston body 8 are not easily broken by this device.

Next, another embodiment of the present invention will be described.
In addition, in the said Example, although the ultrahigh pressure generator comprised with the upper and lower anvils 1 and 4 and four anvils 3 was demonstrated, as shown in FIG. 7, a pair of upper and lower which has a tapered truncated cone-shaped front-end | tip part. A hole 54 in the center between the anvils 51 and 52
It can also be applied to an ultrahigh pressure generator having a hollow anvil (hollow cylinder) 53 having a. The hollow anvil (hollow cylinder) 53 is provided with conical concave grooves corresponding to the truncated cone-shaped tips formed on the anvils 51 and 52, respectively. In short, the present invention is an ultrahigh pressure generating apparatus having an ultrahigh pressure generating chamber which is surrounded by a plurality of anvils and stores a substance, 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 generating chamber, and a thin soft plate 20, anvil tip member 30, and soft material 40 are interposed in the conical recess. It's good.

[0020]

According to the present invention, the loss of the piston driving force is small, the piston and the anvil are not easily broken, and the safety is high, a high compression pressure is obtained, and the frictional force and the constraint with the anvil acting on the piston are obtained. The force can be reduced as much as possible, and the deformation data under ultrahigh pressure can be detected accurately.

[Brief description of drawings]

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

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

FIG. 3 is an illustration of the advantages of the anvil structure according to the present invention.

FIG. 4 is an overall view of an ultrahigh pressure generator.

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

FIG. 6 is an explanatory diagram of the procedure of a deformation characteristic test under ultrahigh pressure.

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

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

9: Prior art I using an anvil with pistons
It is a structure explanatory view.

FIG. 10 is an explanatory view of a force acting on the anvil structure of Prior Art I of FIG. 7.

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

[Explanation 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 20 Thin soft plate 30 Anvil tip member 40 Soft material

Claims (2)

[Claims] 1. An ultra-high pressure generating chamber which is surrounded by a plurality of anvils to contain a substance, and a piston hole is formed in one of the anvils toward the ultra-high pressure generating chamber, and an external force is applied to the piston hole. An ultra-high pressure generator in which a piston body is inserted which is moved to the ultra-high pressure generation chamber side by means of which a conical recess concentric with the piston hole is formed at the tip of the anvil into which the piston body is inserted, And made of a soft material, a thin conical plate-shaped soft plate in which a hole for penetrating the piston body is formed in the center, and a thick wall, a hole for penetrating the piston body is formed in the center, A mortar-shaped anvil tip member in which a conical small recess is formed on the side surface of the ultrahigh pressure generating chamber is provided, and the thin soft plate and the anvil tip member are fitted into the conical recess in that order, and Anvil tip member Ultra high pressure generating apparatus, characterized in that it is interposed soft material between the recesses and holes with the piston body. 2. The ultrahigh 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.