JPS61291034A - Treatment of substance using sphere symmetric implosion chemically performed - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to the processing of materials, and in particular to a method and apparatus for imploding materials into spherically symmetrical shapes.

<Prior Art> It has been proposed in the past to transform graphite into diamond by subjecting the raw material to high-pressure impact compression to change its polymorphism. For example, Garrett, U.S. Pat. No. 3,499,732, 3,653°79.
No. 2 and No. 3,659,972 disclose an electrically detonated shaped explosion to obtain a spherically symmetrical implosion shock wave for forming diamond from graphite or for sintering powdered metals. It is proposed to use manufactured charges. One of the important issues with this technology is the size of the material. In other words, the mass of the explosive material contained is 30
It can be on the order of kilograms. Explosive materials of this size require extreme precautions during loading and also pose problems regarding sample recovery and foreign matter.

Explosive materials cannot be ignited uniformly using the electrical detonation techniques proposed in the prior art methods.

<Problems to be Solved by the Invention> Another major problem with the techniques presented above is the inability to control the implosion pressure obtained by impact compression techniques. A further problem with electrically pyrotechnic explosive devices is that they must detonate in a very precise spherically symmetric manner.

Therefore, an object of the present invention is to reduce the necessity of making the structure of the contents precise, to obtain uniform implosion of the sample material, and to make it easier to recover the product. An object of the present invention is to provide an apparatus and method for imploding a material, which is characterized in that it enables hydrodynamic control of the implosion pressure of a sample material and/or the implosion pressure of a sample material.

A further and more particular object of the present invention is to provide an apparatus and method which makes it possible to obtain uniform implosion energy on a relatively small scale, thereby alleviating the aforementioned deficiencies of the prior art. It is.

Yet another object of the present invention is to obtain post-shock heating (po
It is an object of the present invention to provide an apparatus and a method of the above type for reducing the recursive transformation of a product due to st-5hock heating).

Another object of the invention is an apparatus for precisely tailoring the pressurization time course of a sample to be imploded to chemically and/or physically and/or metallurgically change the final state of the sample. and a method.

In summary, the above and other objects of the present invention are to uniformly irradiate a spherical target containing sample material surrounded by explosive material with a pulsed laser, ion beam, electron beam or microwave beam to ignite the explosive material. This is to obtain uniform spherical implosion of the sample material.

According to a preferred embodiment of the invention, the target includes a thin pyrotechnic layer and a high explosive shell concentrically surrounding the sample material, surrounded by a transparent tamper shell. There is also. The laser nodule irradiation device includes a lens and/or reflector to uniformly focus the ignition energy over the entire surface of the target. By using pulsed laser energy and an optical device designed for spherical irradiation (hereinafter referred to as ``spherical optical device''), it is extremely easy to ignite spherically symmetrical, uniform, high-performance explosive materials. Become. Accordingly, the following preferred embodiment uses a combination of pulsed energy and spherically arranged optics. However, by using multiple beams, high energy electronic, ionic and microwave energy sources can be used in spherical pyrotechnic devices. High energy, pulsed, non-coherent light sources in combination with spherical pyrotechnic devices can also be used.

Other features and advantages of the invention will be detailed below with reference to the accompanying drawings, which illustrate embodiments of the invention.

EXAMPLE A target 10 of the present invention, shown in FIG. 1, includes an inner shell 12 of sample material that is adjacently surrounded and imploded by an outer shell 14 of high explosive material. The hollow portion 16 of the inner shell 12 is preferably a vacuum or low pressure air. The thickness of each element 12, 14 is uniform in the radial direction, and the total outer diameter of the target 10 is from a few millimeters to several tens of centimeters.

Figure 1 shows similar dimensions. The spherical inner shell 12 is imploded by uniform laser firing of the outer surface of the highly explosive shell 14, followed by the outer region detonating and imploding with the associated reaction force, compressing the net payload. do. (“Net load” above and below shall mean all of the material initially driven inward by the explosive force.)
Ignition of the spherical target 10 with uniform laser light can be achieved using a variety of methods. One method uses a large number of individual laser beams and condensing lenses; another method uses two laser beams and a spherical arrangement of elliptical mirrors (FIG. 2).

FIG. 2 does not show the irradiation device 20 that uniformly directs the laser ignition energy onto the entire surface of the target 10. The device 20 includes a silk oval concave reflector 22 with a hole in the center.
．． 24, in which case the near focus of each reflector is on or near the center point between the reflectors on the axis 26, and the far focus of each reflector is on the axis 26. is positioned on a common axis 26 such that it is at the central aperture of the opposite reflector. target・y）I
The axis 26' at the common focus of both mirrors is suspended by a thin wire 28. A set of lenses 30.32 is arranged on the outer axis 26 of the mirrors 22.24 to direct the focused parallel side beams 34.36 of the laser energy through the holes in the adjacent mirrors to the opposite side. It reaches the far focus of the reflector, then reaches the opposite reflector surface and targets 10
Used to focus light on a point. Incident laser beam 3
4,36 are obtained by a suitable pulsed laser amplification device 60 directing the energy to a 50150 beam splitter/reflector 62. The split beams are directed by mirror 64 along paths of equal length to lens 30.32.

Apparatus 20 thus directs pulsed laser energy substantially uniformly onto the target surface. As far as has been explained so far, the basic device 20 is manufactured by Mr.
Applied Optics 14.6 (June 1975) "Laser Fusion Irradiation Device" (1, aserFusion Il.
1267 of lumination system)
- similar to that described on page 1273. Also, U.S. Patent No. 4.0 by Mr. Glass
11.163, No. 4 by Mr. Sigler
, 084,887 and 4,136,926; No. 4,161,351 by Thomas et al.;
al Tllumtnation System O
optimization for La5er Fusi
on Experiments”) Applied Optics 14°6 (
June 1975), pages 1274-1278, describe an improved version by Thomas that can be incorporated into the basic device.

In operation, opposing, focused, parallel side beams of pulsed laser energy are directed in a uniform spherical configuration onto the entire target surface to ignite the high explosive shell 14. A spherically symmetrical explosive reaction occurs within the outer shell 14, inwardly exploding and compressing the material of the inner shell 12. This implosion accelerates the material in the inner shell 12 toward the center of symmetry and pushes the inner shell itself, thereby increasing the density.
The increased pressure and temperature results in physical and/or chemical and/or metallurgical state changes. An important advantage of the spherical implosion technique of the type described is that Guderl
ey) (r Aviation Research J (Luftfahrtf)
Orschung) supra 9,302 (194, 2)], spherical contraction at relatively low temperatures results in a significant increase in density and pressure. The use of spherical impact compaction according to the invention avoids the risk of product material reconverting to its original form due to the low temperatures mentioned above. Furthermore, while compressing said net load,
The high explosive material will expand radially outward. Thus, the dense material does not remain in thermal contact with the compressed sample material. This prevents contamination and contributes to cooling. A cup 38 is placed below the reflector 22.24 to collect the compressed sample.

A water or oil quenching device can also be provided in the cup 38 to further reduce re-transformation.

Target 10 is constructed using standard machining and/or molding techniques. The high performance explosive layer can be molded to suitable dimensions and/or machined. In order to form diamond by polymorphic transitions of graphite induced by implosion, the inner shell 12 may be made of pure graphite or a catalyst, as described in Coinan, U.S. Pat. No. 3,401.019. Ultra-hard boron nitride for industrial machining can be formed by polymorphic transformation of cubic and/or wurtzite type boron nitride by implosion. The method of the invention can be used for the polymerization of ceramics or refractory metals, sintering, compaction of metal alloys, and optionally also for the production of metallic hydrogen.

Explosive shell 14, for example HMX, PETN.

Known as TATB, etc.
See No. 2997-B-M-Dobratz, Law.
rance Livermore Laborator
y, Report # U CRL-52997
) Can be constructed with explosive materials from various companies.

The energy density of common explosive materials is approximately 5KJ/g.
and has a mass density of 1 to 2 g/cc. The inner diameter is 6mm and the outer diameter is 1mm. For an explosive shell 14 of cm, the explosive energy released is approximately 5 KJ. Such an explosion is easily self-contained and can support a "net load" of two diameters and a mass of about 1 g. The maximum pressure at the target surface is over 200 kiloatmospheres, 13
The "point pressure" at a distance of cm, ie at the mirror surface, is only about 10 atmospheres. Pressure impulses have a decay time of a few microseconds. To protect the reflective surface, a replaceable liner 40, 4.2, made for example of transparent soft plastic, can be used.

1ζ FIG. 3 does not show the basic target solenoid 1-10a of the present invention, which includes a core 13 consisting of a solid sphere of sample material 12. The core 13 is completely surrounded by a shell 14 of explosive material. Core 13
The outer surface of the shell 14 and the thickness of the shell 14 are each uniform in the radial direction. In the case of the target material 10b of FIG. 4, the core 13 includes a shell of sample material surrounding the core material 17. Heartwood 1
7 is a spherical solid material such as aluminum, which prevents the implosion pressure within the sample material 12 from becoming too large, and facilitates temporal control of the pressure wave distribution. FIG. 5 shows the target 10 of FIG. 1, with the sample material shell 12 of the core 13 surrounding the hollow portion 16.

In the case of 10c of FIG. 6, a malleable wave forming layer or "propulsion" shell 48, for example made of iron, is positioned between the explosive shell 14 and the core 13. The function of the thruster 48 is to obtain the desired tailoring of the hydrodynamic pressure and temperature distribution during the implosion of the sample core 13 by prolonging the time during which the sample maximum pressure is applied.

In the case of the target solenoid l-10d shown in FIG. 7, the propulsion member 48 is
Multiple concentric shells 5 composed of adjacent materials of different densities to obtain more complex pressure and temperature distribution tillering.
Consists of 0. Such a structure enables sample compression closer to isoen l-Robbie, which was discussed by Lyzenga and Erlang (Δ
A planar shape is suggested by the following. (Rekiuta P-cho p I'I O) by Jun Shimi, American Physical Society Conference Bulletin No. 78.1981) Isentropic compression reduces the temperature increase in the sample caused by the shock wave. Naturally, the core 13 in FIGS. 6 and 7 is
Any of the cores shown in the figure may be used.

100 Joule/cA by 25ns Nd-glass laser or ruby laser to ignite the explosive shell 14
Laser energies with flow densities ranging up to A given explosion +i within the shell 14 requires a certain amount of ignition energy per unit area, which can be easily determined by experiment. A thin (on the order of 1000) aluminum coating or ■b causes the ignition layer 44 to explode I! T1. A modified target 10e is shown in FIG. 8 to reduce the required ignition energy by coating M14 or by providing a thin layer of a chemically reactive explosive material with low ignition sensitivity. The use of thin firing layers is described in connection with planar geometries by Yang et al., Transactions of the Japan Society of Applied Physics, 19.473 (1971), and in U.S. Pat. No. 3,812,783. It is presented. Layer 44 can be formed by standard vacuum deposition or chemical evaporation techniques. Configuring the target in this way requires an ignition energy of up to 10 Joules/Ca and a laser pulse length of 10 ns. FIG. 9 shows yet another modified target saw 10f, in which an incendiary layer 44 is disposed between the explosive shell 14 and the core 13, and the shell 14 is transparent to transmit laser energy. An advantage of the structure of FIG. 9 is that the unburned portion of the explosion shell 14 acts to "intensify" the explosion energy. In this case, both of the cores 13 in Figure 3=5 are the 8th
- Can be used for Figure 9. Similarly, the propulsion section 48 (6th-
7) can be placed between the explosive shell 14 and the wick 13 in FIG. 8 or between the l1t44 and the wick 13 in FIG.

FIGS. 10 and 11 show a "reinforced" target structure 10.
g and 10h are shown. In FIG. 10 and FIG. 1I,
The shell or layer (44 in FIG. 11, 14 in FIG. 10) is surrounded by a spherically continuous transparent glass or plastic tamper acid 46. Most preferably, the tamper acid 46 is elastic and thick enough to absorb the blast energy without damage, which greatly facilitates product collection and protection of the irradiation optics. Become. Dow Corning Company (DoΔ-Corn
Sylgard 184 (5
YLGAII+) 184) is suitable for forming the shell 46. Such shells are formed by standard molding techniques.

EFFECTS OF THE INVENTION An important feature of the invention is that the time course of pressure and temperature can be controlled hydrodynamically by using a layered target structure as illustrated in 10 to 10 h. Such procedures, although quite different in purpose and result, have similar properties to the hydrodynamic controls used to construct inertial fusion targets (Lindl, U.S. Pat. No. 4,272,320 and Mr. Bursokna (
U.S. Patent No. 1,297 by John Brueckner
, No. 165). In the case of the present invention, the sample material is recovered after being imploded, but the inertial fusion target is completely destroyed. Also, in the case of the present invention, the aforementioned hydrodynamic control is employed to effect the desired physical and/or chemical and/or metallurgical changes in the state of the sample material being recovered.

[Brief explanation of drawings]

FIG. 1 is a front view of a 1'I reduced target according to a basic embodiment of the present invention divided into three equal parts, FIG. 2 is a schematic diagram of an optical device for focusing laser ignition energy on the target of FIG. 3-11 are partial cross-sectional views showing various structures of the target of the present invention. DESCRIPTION OF SYMBOLS 10... Target, 12... Inner shell, 13... Core, 14... Outer shell-16... Hollow part, 17... Heart material, 20... Irradiation device, 22, 24...・Reflector, 26
...Axis, 28...Wire, 30.32...Lens, 34.36...Laser beam, 38...Cup. Patent ratio IDM person KM nis fuj, -
john incorboratesodo

Claims (23)

[Claims] (1) (a) providing a target comprising a core having a predetermined amount of selected material with a spherical outer surface and a spherically symmetrical hollow shell formed of high explosive material concentrically surrounding the surface; (b) igniting the shell of high explosive material by directing at least one beam of radiant energy at the target to implode the predetermined amount of material in a spherically symmetrical manner; c) An implosion method for changing the state of a material, characterized in that it comprises the steps of recovering the produced product. 2. The method of claim 1, wherein step (b) includes the step of directing a plurality of beams of radiant energy at the target in a spherically symmetrical manner. 3. The method of claim 2, wherein the energy beam is selected from the group consisting of laser beams, ion beams, electron beams, microwave beams, and non-coherent beams. 4. The method of claim 2, wherein said predetermined amount of selected material comprises a hollow spherical shell having a uniform wall thickness. (5) The method according to claim 4, wherein the interior of the shell is a vacuum. 6. Limiting the implosion pressure of the shell of material by locating a core of solid material within the shell of the sample material. Method. (7) The target further includes an initiator shell adjacent to the shell of high explosive material that ignites the high explosive material in response to the radiant energy. The method described in Section 2. 8. The method of claim 7 further comprising the step of surrounding the target adjacent to a tamper shell that transmits the radiant energy. (9) controlling the distribution of temperature and pressure applied to the core over time by disposing at least one malleable propulsion shell between the core and the high explosive shell; The method according to claim 2, characterized in that: 10. A method according to claim 2, characterized in that the high performance explosive material is selected from the group consisting of HMX, PETN and TATB. (11) implodingly exposing a material to radiant energy characterized by comprising a spherical core having a spherically symmetrical sample of the material surrounded concentrically by a symmetrical shell of high explosive material; target. (12) The target according to claim 11, wherein the core includes a solid sphere of the sample material. (13) The target according to claim 11, wherein the core includes a hollow spherical shell of the sample material. (14) The target according to claim 13, wherein the inside of the shell of the sample material is evacuated. 15. The target of claim 13, wherein the core further includes a solid core material located within and adjacently surrounded by the shell of the sample material. . (16) A claim characterized in that at least one spherically symmetrical shell of malleable material is included between the core and the shell of explosive material to moderate the maximum pressure applied to the sample material. Target according to item 11. (17) The at least one spherically symmetrical shell made of malleable material includes a plurality of radially adjacent shells having different densities of materials. target. (18) The target according to claim 11, further comprising an initiating material shell adjacent to the explosive material shell and igniting the explosive material in response to the radiant energy. (19) The target according to claim 18, wherein the pyrotechnic shell surrounds the explosive shell. (20) Claim 18, characterized in that the pyrotechnic shell is disposed between the high explosive material shell and the core, and the high explosive material shell allows the radiant energy to pass through. Targets listed in section. 21. The target of claim 21 further comprising a spherically symmetrical tamper shell adjacently surrounding the target and transparent to the radiant energy. 22. The target of claim 21, wherein the tamper shell has a thickness sufficient to contain the combustion explosion of the explosive material shell without failure. (23) (a) providing a spherical core of graphite; (b) concentrically surrounding the graphite shell with a shell of high explosive material; and (c) projecting radiant energy into the explosive shell. igniting the high explosive material shell by symmetrically orienting it.