WO2019220032A1

WO2019220032A1 - Device for observation and in situ characterisation of samples under extreme temperature and pressure conditions, and installation comprising such device

Info

Publication number: WO2019220032A1
Application number: PCT/FR2019/051007
Authority: WO
Inventors: Philippe Rosier; Pascal MUNSCH
Original assignee: Centre National De La Recherche Scientifique; Sorbonne Université; Université De Limoges; Institut De Recherche Pour Le Developpement (Ird)
Priority date: 2018-05-15
Filing date: 2019-04-30
Publication date: 2019-11-21
Also published as: FR3081222B1; FR3081222A1

Abstract

The object of the present invention is a device (1) for the observation and in situ characterisation of a sample (2) subjected to very high pressure and heated to a temperature of between 1300K and 1900K, comprising a DAC (3) with diamond anvils (31, 32) arranged on seats (51, 52) which is resistant to high pressure and serves as a high temperature thermal insulator, wherein said DAC (3) is associated with an inductive heating mode (7) having at least one coil (730).

Description

DEVICE FOR IN SITU OBSERVATION AND CHARACTERIZATION OF SAMPLES IN EXTREME CONDITIONS OF TEMPERATURE AND

PRESSURE AND INSTALLATION COMPRISING SUCH A DEVICE

TECHNICAL AREA

The present invention relates to the field of diamond anvil cells (usually referred to by the acronym CED) and their use for the observation and in situ characterization of material samples under extreme conditions of temperature and pressure.

STATE OF THE ART

Experimentation under extreme conditions of pressure and temperature is an essential approach for the understanding of several processes in the fields applied to industry and to those of fundamental research, be it in the Physical Sciences (study of condensed matter and ultra-hard materials) or Earth Sciences (study of planetary interiors, experimental petrology and volcanic events). For several decades, experimental tools have been developed to reproduce in the laboratory different pressure and temperature conditions relevant to their studies.

Among the various devices, the diamond anvil cell (CED) ^{[1] _ [3]} is to date the most versatile and efficient characterization device. Existing in many versions ^[4] , this tool achieves a very wide range of static pressure (up to several hundred GPa) and temperature, up to a few thousand kelvin when this tool is coupled to a device of the laser heating type. An advantage of the CED is the transparency of diamonds in a very wide spectral range, ranging from far infrared to hard X-rays: this allows the observation and characterization, in situ and in real time of processes of transformation of materials to the using a wide variety of investigative methods using laboratory techniques (eg Raman, FTIR, Brillouin) or synchrotron radiation sources.

There are currently two main types of heating for CEDs, namely external heating, generally resistive ^{[5] [9]} , and internal heating using a power laser ^[10] .

The resistive external heating allows a homogeneous heating but limited to about 1300 K. Thus, if one uses for this purpose a resistive heating sleeve (for example based on graphite) around the CED or around the diamonds, this sleeve works reproducibly only up to 700 K (if it's around the CED) or 1300 K (if it's around the diamonds). On the other hand, the internal power laser heating can reach several thousand K, but has intrinsic limits in terms of thermal gradients, time stability and metrology for temperatures below 1700 K.

Therefore, it follows that the temperature range between 1300 and 1900 K is not de facto covered, because of the difficulties related to the generation of the temperature and the absence of a precise metrology.

However, many fundamental natural processes occur however at high pressure precisely in this temperature range. Thus, for example in the case of magmas, surface lavas have temperatures up to 1600 K and deep magmas are over 1500 K. The transition zone (410-660 km) inside the Earth , who is a region of central importance for the understanding of the mantle processes, is characterized by temperatures between 1500 K and 1700 K ^[11] . High pressure experimentation in this temperature range is also of great interest in planetology because it corresponds to that estimated for the deep mantles and nuclei of small telluric planets or the Moon (between 1300 and 1900 K) ^[12] . In materials science, the range between 1300 K and 1900 K is particularly relevant for the fusion and synthesis processes of several materials with remarkable properties.

In fundamental physics, this temperature range is very relevant for studying the liquid phases of alkaline elements (in particular, Li and Na) and molecular compounds (such as C0 ₂ ^[13] and H ₂ 0).

Furthermore, in the DECs, traditional tungsten carbide seats on which the diamond anvils are placed are traditionally used. However, these seats are degraded in the temperature range envisaged (1300 K to 1900 K). If zirconium oxide seats were used instead, these would be thermal insulators up to about 1400 K, and would not withstand the high pressure at such a high temperature.

DESCRIPTION OF THE INVENTION

To solve these defects and disadvantages, the applicant has developed a device for the observation and in situ characterization of a sample subjected to very high pressure and heated to a temperature between 1300 K and 1900 K, including a cell to diamond anvils placed on high pressure resistant seats and constituting high temperature thermal insulation, this CED is associated with an induction heating mode, chosen for its efficiency and simplicity of integration ^[14] .

More particularly, the present invention therefore relates to a device for the observation and in situ characterization of a sample when it is subjected to very high pressures and heated to a temperature between 1300 K and 1900 K, said device comprising:

a diamond anvil cell comprising:

at least one joint comprising substantially planar rhenium and pierced at its center to form the side walls of a high pressure chamber, said seal having an upper planar face and a lower planar face coming into contact with

two diamond anvils which are each fixed in a ceramic seat, said anvils being identical and each comprising a head having a yoke (face in contact with the sample), said anvils being arranged symmetrically with respect to said seal so that each the yokes are respectively in contact with the upper and lower plane faces of said seal and hermetically seal said high-pressure chamber when said anvils are pressurized,

means for pressing the diamonds against each other comprising a substantially cylindrical body and containing said anvils and said seal and a capillary membrane capable of transmitting a clamping force on said anvils, so as to exert a pressure that can go as far as 100 GPa (typically from 20 to 50 GPa) in the high-pressure chamber,

means for guiding said anvils in said body;

means for heating the sample, and

cooling means disposed in or at the outer periphery of said body;

said device being characterized in that said ceramic seats are made of silicon nitride and alumina (ceramic usually designated by the acronym SiAlON), and in that said heating means comprises:

Said joint comprising rhenium,

Two plates or stacks of molybdenum or rhenium plates, which are each pierced at their center so as to surround the head of said diamond anvils, and are in direct contact with said rhenium seal and the diamonds , and

An inductor with at least one turn surrounding said plates or stacks of plates.

For the purposes of the present invention, the term "very high pressure" means a pressure comprised between several tens of MPa and 100 GPa.

The seats made of silicon nitride and alumina (or SiAlON) make it possible to combine mechanical strength under high pressure and thermal insulation at high temperature (greater than 1300 K).

Induction heating using the inductor is simple integration into the device according to the invention and effective and stable in the temperature range 1300 K-1900 K. The heating means of the device according to the invention is adapted to operate under vacuum, and especially in high vacuum between 10 ⁵ mbar and 10 ⁶ mbar. Advantageously, the plates or stacks of plates may each have a thickness of between 0.2 mm and 0.6 mm.

Advantageously, the joint comprising rhenium may have a thickness of between 0.1 mm and 0.4 mm, preferably of the order of 0.2 mm.

Advantageously, the joint comprising rhenium may be surrounded by a ring of high temperature resistant ceramic material.

Advantageously, the joint comprising rhenium may be a composite joint comprising an outer portion of rhenium and a central portion of a material selected from cubic boron nitride (CBN) ^[15] , a kapton-based compound of boron amorphous and epoxy resin ^[16] , or rhenium diboride ^[17] .

Advantageously, the high-pressure chamber may be a cylindrical chamber having a height of between 10 μm and 60 μm and a diameter of between 10 μm and 500 μm.

Advantageously, the cooling means may be in the form of a ring, in which circulates a cooling fluid such as water, this ring being arranged around said diamond anvil cell (CED). It is also possible to use perfluorohexane C ₆ F ₁₄ as heat transfer fluid.

The present invention also relates to an installation for the observation and in situ characterization of a sample when it is subjected to very high pressure and heated to a temperature of between 1300 K and 1900 K, said installation comprising:

A vacuum chamber provided with at least one porthole containing the device according to the invention and the heating means, in which the inductor passes through a vacuum-tight ceramic flange; passing through said body of said diamond anvil cell (CED), and

A pressure generator for putting the membrane of the device according to the invention under very high pressure,

• a vacuum pump connected to the vacuum chamber, which is adapted to produce a vacuum until 10 ^-6 mbar, and

• a means for the observation and / or in situ characterization of the sample.

By pressure generator is meant, in the sense of the presentation device capable of generating a pressure between 0 and 200 bar, such as a compressor or an inflator.

The vacuum chamber of the plant according to the invention allows to create an atmosphere free from oxygen in high vacuum of 10 ^-5 mbar to 10 ^-6 mbar, which avoids diamond graphitization above 1400 K and the deterioration by oxidation of the ceramics present in the device according to the invention (in particular the seats, or possibly the ring of ceramic material surrounding the joint).

The device of the heating means according to the invention is adapted to operate under vacuum, and in particular in vacuum from 10 ^-5 mbar to 10 ^-6 mbar.

As means for observing and / or in situ characterization of the sample that can be used in the installation according to the invention, use may especially be made of a diffractometer, a spectrometer, an infrared pyrometer or a synchrotron-type instrument.

An infrared pyrometer positioned above the porthole of the vacuum chamber is preferably used.

Other advantages and features of the present invention will result from the description which follows, given by way of nonlimiting example and with reference to the appended figures and corresponding examples: Figure 1 shows a schematic sectional view of an exemplary device according to the invention;

Figure 2 shows a detailed sectional view of the CED of the device of Figure 1 showing in particular the heating means;

FIG. 3 represents a schematic view from above of the device according to the invention illustrated in FIG.

1;

FIG. 4 represents a diagrammatic sectional view of an example of an installation according to the invention, showing in particular the CED associated with the heating and cooling means;

FIG. 5 represents a schematic sectional view of an example of an installation according to the invention, showing in particular the vacuum chamber;

FIGS. 6A and 6C are photographs taken at ambient temperature of a diamond anvil of the CED of the installation according to the invention, these photographs having been made before heating (FIG. 6A) and after heating (FIG. 6C),

FIG. 6B is a video image of a diamond anvil taken in situ during an induction heating test at 1400 ° C. (1673.15 K) using the installation according to the invention and recorded with the pyrometer;

Figure 6D is a photograph of a diamond anvil of the CED of the plant according to the invention, which was taken at room temperature after graphitization at 1400 ° C (1673.15 K) under noxal, while Figure 6E (video image taken by the pyrometer) shows that the pyrometric aiming through this diamond graphite is not possible; FIG. 7A is a video image obtained with an infrared pyrometer during a heating test inductively to 1767 ° C (2040.15 K) of a platinum sample under a vacuum of 10 ^-5 mbar (Example 2); Figure 7B shows a photograph of the platinum sample of Figure 7A when fused observed at room temperature;

FIG. 8A is a video image obtained with an infrared pyrometer during an induction heating test at 1300 ° C. (1573.15 K) of an inconel 718 sample, under a vacuum of 10 ⁵ mbar (example 3). );

Figure 8B shows a photograph of the platinum sample of Figure 8A when melted observed at room temperature;

FIGS. 9 and 10 are curves showing the evolution of the temperature as a function of time during a vacuum induction heating test with the aid of the installation according to the invention, with a rhenium seal between the two diamond anvils (Figure 9) and with a stack of three rhenium joints between the two diamond anvils (Figure 10).

The identical elements shown in FIGS. 1 to 5 are identified by identical reference numerals.

Figures 6 to 9 are described in more detail in the following examples, which illustrate the invention without limiting the scope.

DESCRIPTION OF AN EMBODIMENT OF THE DEVICE ACCORDING TO THE INVENTION

FIG. 1 is a diagrammatic cross-sectional view of an exemplary device 1 according to the invention for the observation and in situ characterization of a sample 2 when it is subjected to very high pressure and heated to a high temperature. temperature between 1300 K and 1900 K. Figure 1 shows in particular that the device 1 comprises:

a cell 3 with diamond anvils (CED),

a heating means 71, 72, 73 of the sample 2, and

a cooling means 8 (visible in FIG. 4) disposed in or at the outer periphery of the body 101 of the CED 3 (visible in FIGS. 1 and 3).

FIGS. 1 to 4 show in particular that the diamond anvil cell 3 (CED) comprises:

at least one joint comprising rhenium 30 (visible in FIGS. 2 and 3), which is substantially planar and pierced at its center to form the side walls of a high pressure chamber 4 (visible in FIG. 2), the seal 30 having an upper planar face 301 and a lower planar face 302 in contact with

two identical diamond anvils 31, 32 which are each fixed in a seat 51, 52 (visible in Figures 1 to 3), these anvils 31, 32 each comprising a head 310, 320 having a yoke (face in contact with the sample) and being arranged symmetrically with respect to the seal 30 so that each of the heads of the heads 310, 320 are respectively in contact with the upper planar faces 301 and 302 of the seal 30 and seal the high-pressure chamber 4 when the anvils 31, 32 are pressurized, means for pressing the diamonds 31, 32 against each other.

As regards more particularly the joint comprising rhenium 30 (visible in FIGS. 2 and 3), a gasket whose thickness is of the order of 0.2 mm is used. In the context of this example, the seal 30 is a seal composite material comprising an outer rhenium portion 304 and a central portion 303 of a material selected from cubic boron nitride (CBN), rhenium diboride or a kapton, amorphous boron and epoxy resin compound. This seal is surrounded by a ring 33 made of high-temperature resistant ceramic material which, when very high pressure is applied to the high-pressure chamber 4, hold the anvils 31, 32 in contact with the plates 71, 72. molybdenum or rhenium heating means (see below).

With particular reference to diamond anvils 31, 32, diamonds whose size is adapted to CED are generally used, having a yoke which is truncated either by a flat face, as illustrated in FIGS. 1 and 2, or bevelled. two slopes. In the context of the present exemplary embodiment, it will be advantageous to use diamonds of Almax-Boehler geometry. Each of these anvils 31, 32 is fixed in a seat 51, 52 in SiAlON, for example marketed under the trade name Syalon 050 by International Syalons.

As regards more particularly the means for pressing diamonds 31, 32, these include

A substantially cylindrical body 101 (visible in FIG. 1) which contains the anvils 31, 32 of the CED 3 and the seal 30, and

A capillary membrane 102 resting on a wedge

103 (visible in Figure 1) and adapted to transmit a clamping force on the anvils 31, 32 via a fretted plate 106 (fret 107: plate and hoop visible in Figure 1) pressing on the upper anvil 31 of the CED 3 (see FIG. 2) and a hoop 109 (fret 108: ball and hoop visible in FIGS. and 3) on which is disposed the lower anvil 32 of the CED 3, and

• guiding means 61 anvils 31, 32 in the body 101 consisting of an alignment rod passing through the ball 109 and the plate 106 to align the anvils 31, 32 in the CED 3.

FIG. 2 is a diagrammatic sectional view of the heating means 71, 72, 73 of the CED 3. This comprises, in addition to the gasket comprising rhenium:

Two plates 71, 72 made of molybdenum or rhenium each having a thickness of between 0.2 mm and 0.6 mm, these plates 71, 72 being pierced at their center so as to surround the head 310, 320 of the diamond anvils 31, 32, and are in direct contact with the rhenium seal 30 and diamond diamond anvils 31, 32, and

An inductor 73 with at least one turn 730 18 mm in diameter surrounding the plates 71, 72.

FIG. 4 is a schematic sectional view of the means of the cooling means 8, which is in the form of a ring 8, in which water circulates, this ring being arranged around the CED 3.

DESCRIPTION OF AN EMBODIMENT OF THE INSTALLATION ACCORDING TO

THE INVENTION

FIGS. 4 and 5 are diagrammatic sectional views of an example of an installation according to the invention, FIG. 4 showing in particular the CED 3 associated with the heating means 71, 72, 73, 74 and cooling 8 and the FIG. 5 showing in particular the vacuum chamber 9. These two figures show that this example of installation according to the invention comprises: a vacuum chamber 9 provided with a front porthole 91 (FIG. 5 more exactly showing the housing of the front porthole 91) and a rear porthole 92, this empty chamber 9 containing the device 1 as illustrated on FIGS. 1 to 3 associated with inductor 73 passing through a ceramic flange 74, vacuum tight and passing through the body 101 of the CED 3, the ceramic flange 74 with the inductor 73 being connected to an induction head 76 via an inductor holder 75: in the following examples, the generator CUBE 64 DE 5.6 KW HIGH PERFORMANCE with a heating head 64 SERIE 900 will be used as induction generator; and

A pressure generator (not visible in FIGS. 4 and 5) for putting the capillary membrane 10 of the device under very high pressure

1;

• a vacuum pump (not visible in Figures 4 and 5) connected to said vacuum chamber 9 capable of producing a vacuum until 10 ^-6 mbar, and

An infrared pyrometer (not visible in FIGS. 4 and 5) positioned above the porthole 91.

EXAMPLES

EXAMPLE 1: Start-up of the installation according to the invention

The installation according to the invention illustrated in FIGS. 4 and 5) is used without the CED 3, in which a high vacuum is made in the chamber 9 at 1.5 × 10 ⁵ mbar. It is possible to make measurements under vacuum at 10 ^-4 mbar in about ten minutes and 10 ⁵ mbar in less than 2 hours. A shapal crucible on a pyrophilite washer is inserted in the center of coil 73. A 5x5 mm ² joint of Rhenium serves as a heating element in response to induction. Induction was tested up to 1780 ° C (2053.15 K) on the vacuum rhenium seal.

EXAMPLE 2: Study of the non-graphitization of diamonds

Induction heating tests were carried out at 1400 ° C. (1673.15 K) in the plant according to the invention without the CED 3 (as in Example 1), in which a cut diamond of Almax-geometry was placed. Boehler on a rhenium joint in the installation according to the invention. These tests are illustrated by FIGS. 6A to 6E:

Figure 6A shows the diamond before heating: yellowish appearance, the facets are clearly visible by the cylinder head. Upon heating, the video image clearly shows the color of the rhenium seal through the diamond (Figure 6B). The latter is not opaque;

Figure 6C confirms to the naked eye what we see with the pyrometer, the diamond is transparent.

For these tests, the cumulative heating time is one hour, with a vacuum level maintained between 1.5 and 3.10 ^-5 mbar.

The same brightness and transparency of the lamp reflection on the rhenium joint is observed in the chamber 9.

It is observed that there was no total graphitization of the diamond at 1400 ° C (1673.15 K) at this level of vacuum, nor even a graphite web that could hinder the optical operation.

An example of opaque diamond (obtained after graphitization at 1400 ° C (1673.15 K) under noxal) is shown in Figure 6D Figure 6E shows that it is impossible to make a pyrometric aiming through this diamond. EXAMPLE 3: Calibration of the pyrometer

An OPTRIS CTV 2MH1 CFV CB3C infrared pyrometer with integrated video output is used. This pyrometer makes it possible to raise the temperature from 490 ° C to 2000 ° C (ie between 763.15 K and 2273.15 K) on metal bodies with a focal length of 100 mm and over a zone of 0.3 mm in diameter.

In order to calibrate the pyrometer, we have, in the shapal crucible on a rhenium joint in the center of the coil 73, different metallic samples, which are heated until they reach their melting point:

up to 1085 ° C (1358.15 K), visualizing the melting of a piece of copper,

up to 1335 ° C (1608.15 K) by visualizing the melting of a piece of Inconel 718, as illustrated in Figures 8A and 8B, and

up to 1768 ° C (2041.15 K) by visualizing platinum fusion, as shown in Figures 7A and 7B.

This made it possible to define the emissivity coefficient at 0.3 for the Rhenium seal.

EXAMPLE 4

Induction heating tests are carried out under vacuum using the installation according to the invention, with a rhenium seal between the two diamond anvils (FIG. 9) and with a stack of three rhenium joints between the two anvils. diamond (Figure 10).

Induction acts on conductive materials. The greater the volume of the heating means, the greater the power deposited on these furnaces by induction.

Thus we see that with a single rhenium seal between the diamond anvils (see Figure 9), the power applied to the rhenium seal 30 is quite low since it takes 600 seconds to reach 1600 ° C (1873.15 K), with a power that is set on the generator of 100%. Despite this, we still succeed in achieving our goal.

With three seals (see Figure 10), the power applied to the rhenium seal 30 is then much larger since it takes only 200 seconds to reach 1600 ° C (1873.15 K), with only 80% of power set on the generator. This leaves a safety margin on the installation.

The curves in FIGS. 9 and 10 also show that the rise in temperature is quite fast (200 seconds), which opens up prospects for fundamental research, especially relating to the study of materials in high pressure thermal cycling.

REFERENCES

[1] Weir C.E., et al. (1959) J. Res. Nat. Off. Standards (US) 63A, 55-62.

[2] Jamiesen J.C. et al. (1959), Rev. Sci. Instr. 30, 1016-

1019.

[3] Van Valkenburg A. (1964) Diamond Research 1964, 17-20.

[4] Bassett W.A. (2009) High Pressure Research, 29, 163-186

[5] Bassett W. A. (2003) Eur. J. Miner., 15, 773-780.

[6] Burchard et al., (2003) Rev Sci. Instr. 74, 1263.

[7] Petitgirard S. et al. (2009) Rev. Sci. Instr. 80, 033906.

[8] Pasternack S. et al. (2008) Rev. Sci. Instr. 79, 085103.

[9] Munsch P. et al. (2015) Eur. J. Miner. 27, 365-375.

[10] Tateno S. et al. (2010) Phys. Earth and Planet. Int. 181

54-59.

[11] Frost D.J. (2008) Elements 4, 171-176.

[12] Antonangeli et al., (2015) PNAS 112 (13), 3916-3919.

[13] Datchi et al. (2016) Phys. Rev. B94.014201

[14] Keiji Shinoda et al. (2008) AIP, Rev. Sci. Instr. 79

015101

[15] Lobanov et al (2015) J. Appl. Phys. 118, 035905

[16] S. Merkel & T. Yagi Rev. Sci. Instrum. , 76, 046109 (2005)

[17] Hsiu-Ying Chung et al (2007) Science 316, 436

Claims

1. Device (1) for the observation and in situ characterization of a sample (2) when subjected to very high pressure and heated to a temperature of between 1300 K and 1900 K, said device (1) comprising :

a diamond anvil cell (3) comprising: at least one gasket comprising substantially planar rhenium (30) and pierced at its center to form the side walls of a high pressure chamber (4), said gasket (30) having an upper planar face (301) and a lower planar face (302) to come into contact with

two diamond anvils (31, 32) which are each fixed in a ceramic seat (51, 52), said anvils (31, 32) being identical and each comprising a head (310, 320) having a yoke (face in contact with the sample), said anvils (31, 32) being arranged symmetrically with respect to said seal (30) so that each of the heads of said heads

(310, 320) are respectively in contact with the upper (301) and lower (302) planar faces of said seal (30) and hermetically seal said high pressure chamber (4) when said anvils (31, 32) are pressurized ,

means for pressing the diamonds (31, 32) against each other comprising a body (101) substantially cylindrical and containing said anvils (31, 32) and said seal (30) and a capillary membrane (102) adapted to transmitting a clamping force on said anvils (31, 32), in order to maintain a pressure of up to 100 GPa in the high-pressure chamber (4),

guide means (61) for said anvils (31, 32) in said body (101);

heating means (71, 72, 73) of said sample (2), and

cooling means (8) disposed in or at the outer periphery of said body (101); said device (1) being characterized in that said ceramic seats (51, 52) are made of silicon nitride and alumina, and

in that said heating means (7) comprises:

Said seal (30) comprising rhenium,

Two plates (71, 72) or stacks of molybdenum or rhenium plates, each of which is pierced at their center so as to surround the head (310, 320) of said diamond anvils (31, 32); ), and are in direct contact with said rhenium seal (30) and the diamonds, and

An inductor (73) with at least one turn (730) surrounding said plates (71, 72) or stacks of plates.

2. Device (1) according to claim 1, characterized in that the plates (71, 72) or plate stacks each have a thickness of between 0.2 mm and 0.6 mm.

3. Device (1) according to claims 1 or 2, characterized in that said seal (30) comprising rhenium has between 0.1 mm and 0.4 mm, preferably of the order of 0.2 mm.

4. Device (1) according to any one of claims 1 to 3, characterized in that said seal (30) comprising rhenium is surrounded by a ring (33) of ceramic material resistant to high temperature.

5. Device (1) according to any one of claims 1 to 4, characterized in that said seal (30) comprising rhenium is a composite seal has an outer portion (304) rhenium and a central portion

(303) of a material selected from cubic boron nitride, rhenium diboride or a kapton, amorphous boron and epoxy resin compound.

6. Device (1) according to any one of claims 1 to 4, characterized in that said high pressure chamber (4) is a cylindrical chamber having a height of between 10 ym and 60 ym and a diameter between 10 ym and 500 ym.

7. Device (1) according to any one of claims 1 to 3, characterized in that said cooling means (8) is a ring in which circulates a cooling fluid (81), said ring (8) being arranged around of said diamond anvil cell (3) (CED)

8. Installation for in-situ observation and characterization of a sample (2) when subjected to very high pressure and heated to a temperature of between 1300 K and 1900 K, said installation comprising:

A vacuum chamber (9) provided with at least one porthole (91) containing a device (1) as defined according to any one of claims 1 to 7 and said heating means (7), in which the inductor passes through a flange (74) in vacuum sealed ceramic core passing through said body (101) of said diamond anvil cell (3), and

A pressure generator for putting the membrane (10) of said device (1) under very high pressure,

• a vacuum pump connected to said vacuum chamber (9) adapted to produce a vacuum up to 10 ^-6 mbar, and

• a means for the observation and / or in situ characterization of the sample (2).

9. Installation according to claim 8, wherein said means for the observation and / or characterization of the sample (2) is an infrared pyrometer positioned above the porthole (91).