Hydrogen filling method, hydrogen filling device, sample analysis method, and sample analysis device

Abstract

To provide a hydrogen filling method and a hydrogen filling device that are highly safe and low cost and can fill hydrogen into a sample under atmospheric pressure.SOLUTION: Provided is a method for filling hydrogen into a sample 1 formed of metal, and the method includes: (a) a step of converting hydrogen-containing gas into low-temperature plasma under atmospheric pressure; and (b) a step of bringing the hydrogen-containing gas converted into the low-temperature plasma into contact with a surface 1a of the sample 1 under atmospheric pressure.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a hydrogen filling method, a hydrogen filling device, a sample analysis method, and a sample analysis device.

Background Art

[0002] In the development of high-strength steel, hydrogen embrittlement, in which strength and toughness deteriorate due to hydrogen, is a major problem. However, the material structural changes related to hydrogen embrittlement have not been clarified, and in order to elucidate the mechanism of hydrogen embrittlement, it is desirable to perform observations over time while introducing hydrogen into steel.

[0003] For example, Patent Document 1 discloses a method of filling hydrogen by exposing a test piece to high-pressure hydrogen gas. Further, Patent Document 2 discloses a method of immersing a steel material in an electrolytic solution and electrochemically filling hydrogen. Furthermore, Patent Document 3 discloses a sample analysis method capable of analyzing the sample surface with high resolution and over time using an electron beam device while introducing hydrogen into the sample.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the method described in Patent Document 1, since high-pressure hydrogen gas is used, there is a risk of explosion. Therefore, large-scale facilities such as pressure vessels, gas compressors, and explosion-proof infrastructure are required, resulting in a problem of high cost. Also, usually, a microscope cannot be used in high-pressure hydrogen gas structurally.

[0006] In addition, in the method described in Patent Document 2, although it is possible to efficiently fill hydrogen, since hydrogen bubbles are generated on the surface of the sample in the electrolytic solution, there is a risk of hindering the observation when performing in-situ observation using a microscope.

[0007] In the method described in Patent Document 3, since observation is performed using an electron microscope or the like, it is possible to analyze the sample surface with high resolution over time. On the other hand, since the time resolution when clearly observing the sample surface using an electron microscope is about several seconds, when performing in-situ observation with higher time resolution, the development of other complementary techniques is required.

[0008] As a result of the inventors' study, it was conceived that in order to perform in-situ observation with high time resolution, an optical microscope, a laser microscope, etc. are suitable, and in order to install them, it is necessary to develop a method of filling hydrogen under atmospheric pressure.

[0009] The present invention aims to solve the above problems, and provides a hydrogen filling method and a hydrogen filling device that are highly safe, low-cost, and capable of filling hydrogen into a sample under atmospheric pressure, and a sample analysis method and a sample analysis device capable of analyzing the sample surface over time with high time resolution while filling hydrogen into the sample.

Means for Solving the Problems

[0010] The present invention has been made to solve the above problems, and its gist lies in the following hydrogen filling method, hydrogen filling device, sample analysis method, and sample analysis device.

[0011] (1) A method for filling a sample made of metal with hydrogen, comprising: (a) a step of generating low-temperature plasma of a hydrogen-containing gas under atmospheric pressure; (b) a step of bringing the low-temperature plasma-generated hydrogen-containing gas into contact with the surface of the sample under atmospheric pressure. Hydrogen filling method.

[0012] (2) In the step (a), the hydrogen-containing gas is generated into low-temperature plasma under atmospheric pressure by generating dielectric barrier discharge in the hydrogen-containing gas. The hydrogen filling method according to (1) above.

[0013] (3) In the step (a), an alternating voltage is applied between the electrode and the sample, and the electrode and the sample are electrically connected through a dielectric and the hydrogen-containing gas to generate dielectric barrier discharge. The hydrogen filling method according to (2) above.

[0014] (4) In the step (a), an alternating voltage is applied between a pair of electrodes, and the pair of electrodes are electrically connected through a dielectric and the hydrogen-containing gas to generate dielectric barrier discharge. The hydrogen filling method according to (2) above.

[0015] (5) In the step (b), the low-temperature plasma-generated hydrogen-containing gas is brought into contact with the surface under atmospheric pressure while the temperature of the surface is controlled at a predetermined temperature. The hydrogen filling method according to any one of (1) to (4) above.

[0016] (6) An apparatus for filling a sample made of metal with hydrogen, comprising: a plasma generation unit that generates low-temperature plasma of a hydrogen-containing gas under atmospheric pressure; a gas supply unit that supplies the hydrogen-containing gas so that the low-temperature plasma-generated hydrogen-containing gas comes into contact with the surface of the sample under atmospheric pressure. Hydrogen filling apparatus.

[0017] (7) The plasma generation unit generates dielectric barrier discharge in the hydrogen-containing gas to convert the hydrogen-containing gas into low-temperature plasma under atmospheric pressure. The hydrogen filling device according to (6) above.

[0018] (8) The plasma generation unit includes an electrode and a dielectric. An alternating voltage is applied between the electrode and the sample, and the electrode and the sample are electrically connected through the dielectric and the hydrogen-containing gas to generate dielectric barrier discharge. The hydrogen filling device according to (7) above.

[0019] (9) The plasma generation unit includes a pair of electrodes and a dielectric. An alternating voltage is applied between the pair of electrodes, and the pair of electrodes are electrically connected through the dielectric and the hydrogen-containing gas to generate dielectric barrier discharge. The hydrogen filling device according to (7) above.

[0020] (10) It further includes a temperature control unit that controls the temperature of the surface to a predetermined temperature. The gas supply unit supplies the hydrogen-containing gas so that the low-temperature plasma-converted hydrogen-containing gas contacts the surface under atmospheric pressure in a state where the temperature of the surface is controlled to a predetermined temperature. The hydrogen filling device according to any one of (6) to (9) above.

[0021] (11) A method for analyzing a sample made of metal, The steps (a) and (b) according to any one of (1) to (4) above, and (c) a step of analyzing the surface in a state where the low-temperature plasma-converted hydrogen-containing gas is in contact therewith under atmospheric pressure. Sample analysis method.

[0022] (12) A method for analyzing a sample made of metal, The steps (a) and (b) according to (5) above, and (c) a step of analyzing the surface in a state where the low-temperature plasma hydrogen-containing gas is in contact therewith under atmospheric pressure; Sample analysis method.

[0023] (13) An analyzer for a sample made of metal, comprising: the plasma generation unit and the gas supply unit according to any one of (6) to (9) above; (c) an analysis unit that analyzes the surface in a state where the low-temperature plasma hydrogen-containing gas is in contact therewith under atmospheric pressure; Sample analyzer.

[0024] (14) An analyzer for a sample made of metal, comprising: the plasma generation unit and the gas supply unit according to (10) above; (c) an analysis unit that analyzes the surface in a state where the low-temperature plasma hydrogen-containing gas is in contact therewith under atmospheric pressure; Sample analyzer.

Advantages of the Invention

[0025] According to the present invention, it is highly safe, low-cost, and capable of filling hydrogen into a sample under atmospheric pressure. Furthermore, it is possible to analyze the sample surface with high time resolution over time while filling hydrogen into the sample under atmospheric pressure.

Brief Description of the Drawings

[0026]

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Mode for Carrying Out the Invention

[0027] A hydrogen filling method, a hydrogen filling device, a sample analysis method, and a sample analysis device according to an embodiment of the present invention will be described with reference to FIGS. 1 to 6.

[0028] FIG. 1 is a diagram showing a schematic configuration of a hydrogen filling device 100 according to an embodiment of the present invention. The hydrogen filling device 100 is a device for filling a sample 1 made of metal with hydrogen, and includes a plasma generation unit 11 and a gas supply unit 12.

[0029] The plasma generation unit 11 generates low-temperature plasma of a hydrogen-containing gas under atmospheric pressure. In the configuration shown in FIG. 1, the plasma generation unit 11 includes an electrode 11a made of a copper plate and a dielectric 11c made of a glass plate. The dielectric 11c is provided on the electrode 11a side between the electrode 11a and the sample 1. Then, an alternating voltage is applied between the sample 1 and the electrode 11a using an AC power supply 11e.

[0030] At this time, since a hydrogen-containing gas is supplied between the sample 1 and the dielectric 11c by the gas supply unit 12 described later, the electrode 11a and the sample 1 are in a state (discharge) of being electrically connected via the dielectric 11c and the hydrogen-containing gas. As a result, dielectric barrier discharge occurs in the hydrogen-containing gas between the sample 1 and the dielectric 11c, and the hydrogen-containing gas is turned into low-temperature plasma under atmospheric pressure.

[0031] The gas supply unit 12 supplies the hydrogen-containing gas so that the low-temperature plasma hydrogen-containing gas contacts the surface 1a of the sample 1 under atmospheric pressure. In the configuration shown in FIG. 1, by supplying and filling the hydrogen-containing gas between the sample 1 and the dielectric 11c, it becomes possible to bring the low-temperature plasma hydrogen-containing gas into contact with the surface 1a. Then, by bringing the low-temperature plasma hydrogen-containing gas into contact with the surface 1a, the sample 1 is filled with hydrogen.

[0032] In the configuration shown in FIG. 1, the sample 1 and the AC power supply 11e are directly connected. However, by placing the sample 1 on a conductive sample stage (not shown), it may be indirectly connected to the AC power supply 11e via the sample stage.

[0033] FIG. 2 is a diagram showing a schematic configuration of a hydrogen filling device 200 according to another embodiment of the present invention. In the configuration shown in FIG. 2, the plasma generation unit 21 includes an electrode 21a made of copper foil and a dielectric 21c made of a cylindrical glass capillary. The electrode 21a is provided so as to cover the outer periphery of the dielectric 21c, and the tip of the dielectric 21c protrudes toward the sample 2 side from the electrode 21a.

[0034] The hydrogen-containing gas is supplied from the inside of the cylindrical dielectric 21c by the gas supply unit 22 and is sprayed onto the surface 2a of the sample 2 through the tip of the dielectric 21c. In this state, by applying an alternating voltage between the sample 2 and the electrode 21a using the AC power supply 21e, the electrode 21a and the sample 2 are electrically connected via the dielectric 21c and the hydrogen-containing gas, and dielectric barrier discharge occurs in the hydrogen-containing gas inside the dielectric 21c and in the hydrogen-containing gas sprayed from the tip of the dielectric 21c onto the surface 2a, and the hydrogen-containing gas is converted into low-temperature plasma under atmospheric pressure. As a result, it becomes possible to bring the low-temperature plasma-converted hydrogen-containing gas into contact with the surface 2a.

[0035] In the configuration shown in FIG. 2, the sample 2 and the AC power supply 21e are directly connected. However, by placing the sample 2 on a conductive sample stage (not shown), it may be indirectly connected to the AC power supply 21e via the sample stage.

[0036] FIG. 3 is a diagram showing a schematic configuration of a hydrogen filling device 300 according to another embodiment of the present invention. In the configuration shown in FIG. 3, the plasma generation unit 31 includes a pair of electrodes 31a and 31b made of copper plates and a pair of dielectrics 31c and 31d made of glass plates. The pair of dielectrics 31c and 31d are both provided between the pair of electrodes 31a and 31b, one dielectric 31c is in contact with one electrode 31a, and the other dielectric 31d is in contact with the other electrode 31b. In the configuration shown in FIG. 3, the dielectrics are provided on both sides of the pair of electrodes 31a and 31b, but they may be provided on only one side.

[0037] The hydrogen-containing gas is supplied between the pair of dielectrics 31c and 31d by the gas supply unit 32. In this state, by applying an alternating voltage between the pair of electrodes 31a and 31b using the AC power supply 31e, the pair of electrodes 31a and 31b are electrically connected via the dielectrics 31c and 31d and the hydrogen-containing gas, and dielectric barrier discharge occurs in the hydrogen-containing gas between the dielectrics 31c and 31d, and the hydrogen-containing gas is converted into low-temperature plasma under atmospheric pressure.

[0038] In addition, the gas supply unit 32 can bring the hydrogen-containing gas that has been converted into low-temperature plasma into contact with the surface 3a by adjusting the supply direction, flow rate, and flow velocity of the hydrogen-containing gas so that the hydrogen-containing gas supplied between the pair of dielectrics 31c and 31d is blown onto the surface 3a of the sample 3.

[0039] In the configuration shown in FIG. 3, the sample 3 is grounded, but it is not necessarily required to be grounded.

[0040] FIG. 4 is a diagram showing a schematic configuration of a hydrogen filling device 400 according to another embodiment of the present invention. In the configuration shown in FIG. 4, the plasma generation unit 41 includes a pair of electrodes 41a and 41b made of copper foil and a dielectric 41c made of a cylindrical glass capillary. The pair of electrodes 41a and 41b are respectively provided so as to cover the outer periphery of the dielectric 41c, and the tip of the dielectric 41c protrudes toward the sample 4 side from the electrode 41b.

[0041] The hydrogen-containing gas is supplied from the inside of the cylindrical dielectric 41c by the gas supply unit 42 and is blown onto the surface 4a of the sample 4 through the tip of the dielectric 41c. In this state, by applying an alternating voltage between the pair of electrodes 41a and 41b using the AC power supply 41e, the pair of electrodes 41a and 41b are electrically connected through the dielectric 41c and the hydrogen-containing gas, and dielectric barrier discharge occurs in the hydrogen-containing gas inside the dielectric 41c, and the hydrogen-containing gas is converted into low-temperature plasma under atmospheric pressure. As described above, since the hydrogen-containing gas is blown onto the surface 4a through the tip of the dielectric 41c, it is possible to bring the hydrogen-containing gas that has been converted into low-temperature plasma into contact with the surface 4a.

[0042] In the configuration shown in FIG. 4, the sample 4 is grounded, but it is not necessarily required to be grounded.

[0043] FIG. 5 is a diagram showing a schematic configuration of a hydrogen filling apparatus 500 according to another embodiment of the present invention. In the configuration shown in FIG. 5, the hydrogen filling apparatus 500 includes a temperature control unit 53 in addition to the plasma generation unit 51 and the gas supply unit 52. Since the configurations of the plasma generation unit 51 and the gas supply unit 52 are the same as those of the plasma generation unit 21 and the gas supply unit 22 shown in FIG. 2, the description thereof is omitted. In the example shown in FIG. 5, the configurations of the plasma generation unit 51 and the gas supply unit 52 are the same as those of the plasma generation unit 21 and the gas supply unit 22 shown in FIG. 2, but may be the same as the configurations shown in FIG. 1, 3, or 4.

[0044] The temperature control unit 53 controls the temperature of the surface 5a of the sample 5 to a predetermined temperature. For example, it is possible to keep the temperature of the surface 5a at a high temperature or at a low temperature. With the temperature of the surface 5a controlled to a predetermined temperature, by bringing the hydrogen-containing gas that has been converted into low-temperature plasma into contact with the surface 5a under atmospheric pressure, it becomes possible to fill the sample 5 with hydrogen under various temperature conditions. In the present invention, since low-temperature plasma is utilized, it is possible to minimize the influence on the temperature of the surface 5a by bringing the hydrogen-containing gas that has been converted into low-temperature plasma into contact with the surface 5a under atmospheric pressure.

[0045] FIG. 6 is a diagram showing a schematic configuration of a sample analysis apparatus 600 according to an embodiment of the present invention. The sample analysis apparatus 600 is an analysis apparatus for a sample 6 made of metal, and includes a plasma generation unit 61, a gas supply unit 62, and an analysis unit 63. Since the configurations of the plasma generation unit 61 and the gas supply unit 62 are the same as those of the plasma generation unit 21 and the gas supply unit 22 shown in FIG. 2, the description thereof is omitted. In the example shown in FIG. 6, the configurations of the plasma generation unit 61 and the gas supply unit 62 are the same as those of the plasma generation unit 21 and the gas supply unit 22 shown in FIG. 2, but may be the same as the configurations shown in FIG. 1 or 3 to 5.

[0046] The analysis unit 63 analyzes the surface 6a of the sample 6 in a state where the hydrogen-containing gas in a low-temperature plasma state is in contact therewith, under atmospheric pressure. In the configuration shown in FIG. 6, the analysis unit 63 is an optical microscope, but is not limited thereto, and a laser microscope, a white interference microscope, an X-ray microscope, an ultrasonic microscope, or the like can be used. As described above, in the present invention, since hydrogen can be filled under atmospheric pressure, an optical microscope or the like can be easily installed and used, and has high time resolution. Therefore, by analyzing the surface 6a using the analysis unit 63 such as an optical microscope, for example, it is possible to analyze the state of hydrogen embrittlement occurring over time with high time resolution.

[0047] In the above description, there is no particular limitation on the type of the sample as long as it is a metal. For example, it includes carbon steel, alloy steel, stainless steel, Ni-based alloy, Al alloy, Ti alloy, etc. In particular, carbon steel has a large hydrogen diffusion coefficient, and it is difficult to hold it in a state filled with hydrogen for a long time under atmospheric pressure. Therefore, when carbon steel is the target, the hydrogen filling method, hydrogen filling device, sample analysis method, and sample analysis device according to the present invention can be preferably used.

[0048] Also, there is no particular limitation on the shape of the sample. For example, it may be plate-shaped, cylindrical, or in the shape of an actual product (for example, bolt shape). There is no particular limitation on the dimensions of the sample 1 either. For example, a part (cut end face or joint) of a member having a size on the order of several meters such as an automobile body can be targeted, or a micro test piece having a size on the order of several millimeters can be targeted.

[0049] The hydrogen-containing gas is preferably a mixed gas of an inert gas (noble gas, nitrogen, carbon dioxide) and hydrogen. More preferably, it is a mixed gas of helium and hydrogen. The reason for this preference is that it is easy to control the discharge and no chemical reaction occurs between the sample and the gas.

[0050] There is no particular limitation on the hydrogen concentration in the hydrogen-containing gas. However, if the hydrogen concentration is too high, there is a risk of explosion due to ignition (discharge), so it is preferably 6 vol% or less. On the other hand, if the hydrogen concentration is too low, there is a risk that the sample may not be filled with a sufficient amount of hydrogen, so it is preferably 0.1 vol% or more.

[0051] There is also no particular limitation on the conditions of the alternating voltage as long as dielectric barrier discharge occurs. The frequency is preferably 0.01 kHz to 1000 kHz, and the voltage amplitude is preferably 1 kV to 100 kV. The waveform of the alternating voltage may be a trapezoidal wave, a square wave, a triangular wave, etc. in addition to a sine wave. There is also no particular limitation on the distance between the dielectric and the sample as long as dielectric barrier discharge occurs, and for example, it can be 1 mm to 50 mm.

[0052] Examples of the materials for the electrodes and the sample stage include copper, silver, aluminum, iron, etc. with good conductivity. Examples of the materials for the dielectric include glass materials, ceramic materials such as alumina and aluminum nitride, polymers, etc.

[0053] In the present invention, "under atmospheric pressure" refers to an environment of about 100 kPa. It is intended to distinguish from a vacuum environment and a high-pressure environment, and it is not necessary to be exactly 1 atmosphere. Also, low-temperature plasma means plasma in which the temperature of the gas in the plasma (hereinafter also referred to as plasma temperature) is 800°C or less.

[0054] If the plasma temperature is too high, the sample may be thermally damaged. The plasma temperature is more preferably 700°C or less, even more preferably 400°C or less, and even more preferably 200°C or less. Also, since low-temperature plasma can have a plasma temperature of about room temperature (30°C), the safety is extremely high. The control of the plasma temperature can be performed by adjusting the frequency of the alternating voltage, the voltage amplitude, or the gas flow rate of the hydrogen-containing gas, etc.

[0055] In addition, in the configuration exemplified above, by generating dielectric barrier discharge, a hydrogen-containing gas is converted into low-temperature plasma under atmospheric pressure. Dielectric barrier discharge is preferable because it is easy to control discharge, the equipment is inexpensive, the safety is high, and the discharge is uniform. However, the present invention is not limited to this, and other methods for converting a hydrogen-containing gas into low-temperature plasma under atmospheric pressure include corona discharge, microwave discharge, RF discharge, and the like.

[0056] Hereinafter, the present invention will be described more specifically by way of examples, but the present invention is not limited to these examples.

Example

[0057] As a sample, a quenched JIS-SCM435 steel material (tensile strength: 1.9 GPa) was used. Test pieces having the dimensions and shape shown in FIG. 7 were taken from this sample, and a wedge having the dimensions and shape shown in FIG. 8 was inserted into the notch portion to introduce a pre-crack shown in FIG. 9. The wedge was held in a state of being inserted into the test piece, and a constant strain was applied to the test piece.

[0058] Thereafter, while filling hydrogen into the sample by spraying the low-temperature plasma hydrogen-containing gas near the tip of the pre-crack using the sample analysis apparatus shown in FIG. 6, in-situ observation was carried out with an optical microscope. The hydrogen-containing gas was a mixed gas of 95 vol% helium and 5 vol% hydrogen, and the flow rate was 200 mL / min. The frequency of the alternating voltage was 1 kHz, and the voltage amplitude was 10 kV.

[0059] As a result, as shown in FIG. 10, it was possible to observe the progress of the crack due to hydrogen embrittlement. Further, as a result of observing the crack at a higher magnification, as shown in FIG. 11, it was confirmed that it was intergranular cracking, which is also a characteristic of hydrogen embrittlement cracking.

Industrial Applicability

[0060] According to the present invention, it is highly safe, low-cost, and capable of filling hydrogen into a sample under atmospheric pressure. Furthermore, while filling hydrogen into the sample, it becomes possible to analyze the surface of the sample with high time resolution over time under atmospheric pressure.

Explanation of reference numerals

[0061] 1,2,3,4,5,6. Sample 1a,2a,3a,4a,5a,6a. Surface 11,21,31,41,51,61. Plasma generation unit 11a,21a,31a,31b,41a,41b,51a,61a. Electrode 11c,21c,31c,31d,41c,51c,61c. Dielectric 11e,21e,31e,41e,51e,61e. Alternating current power supply 12,22,32,42,52,62. Gas supply unit 100,200,300,400,500. Hydrogen filling device 600. Sample analysis device

Claims

1. A method for filling a sample made of metal with hydrogen, comprising: (a) a step of subjecting a hydrogen-containing gas to low-temperature plasma under atmospheric pressure; (b) a step of bringing the low-temperature plasma hydrogen-containing gas into contact with the surface of the sample under atmospheric pressure. A hydrogen filling method.

2. In the step (a), the hydrogen-containing gas is subjected to low-temperature plasma under atmospheric pressure by generating dielectric barrier discharge in the hydrogen-containing gas. The hydrogen filling method according to Claim 1.

3. In the step (a), an alternating voltage is applied between the electrode and the sample, and the electrode and the sample are electrically connected through a dielectric and the hydrogen-containing gas to generate dielectric barrier discharge. The hydrogen filling method according to Claim 2.

4. In the step (a), an alternating voltage is applied between a pair of electrodes, and the pair of electrodes are electrically connected through a dielectric and the hydrogen-containing gas to generate dielectric barrier discharge. The hydrogen filling method according to Claim 2.

5. In the step (b), the low-temperature plasma hydrogen-containing gas is brought into contact with the surface under atmospheric pressure while the temperature of the surface is controlled at a predetermined temperature. The hydrogen filling method according to any one of Claims 1 to 4.

6. An apparatus for filling a sample made of metal with hydrogen, comprising: a plasma generation unit that subjects a hydrogen-containing gas to low-temperature plasma under atmospheric pressure; a gas supply unit that supplies the hydrogen-containing gas so that the low-temperature plasma hydrogen-containing gas comes into contact with the surface of the sample under atmospheric pressure. A hydrogen filling apparatus.

7. The plasma generation unit subjects the hydrogen-containing gas to low-temperature plasma under atmospheric pressure by generating dielectric barrier discharge in the hydrogen-containing gas. The hydrogen filling apparatus according to Claim 6.

8. The plasma generation unit includes an electrode and a dielectric, and an alternating voltage is applied between the electrode and the sample, and the electrode and the sample are electrically connected through the dielectric and the hydrogen-containing gas to generate dielectric barrier discharge. The hydrogen filling apparatus according to Claim 7.

9. The plasma generation unit includes a pair of electrodes and a dielectric, and an alternating voltage is applied between the pair of electrodes, and the pair of electrodes are electrically connected through the dielectric and the hydrogen-containing gas to generate dielectric barrier discharge. The hydrogen filling apparatus according to Claim 7.

10. Further comprising a temperature control unit that controls the temperature of the surface to a predetermined temperature. The gas supply unit supplies the hydrogen-containing gas such that the hydrogen-containing gas that has been converted into low-temperature plasma contacts the surface under atmospheric pressure while the temperature of the surface is controlled to a predetermined temperature. The hydrogen filling device according to any one of claims 6 to 9.

11. An analysis method for a sample made of metal, comprising: The steps (a) and (b) according to any one of claims 1 to 4, and (c) a step of analyzing the surface in a state where the low-temperature plasma hydrogen-containing gas is in contact therewith under atmospheric pressure. Sample analysis method.

12. An analysis method for a sample made of metal, comprising: The steps (a) and (b) according to claim 5, and (c) a step of analyzing the surface in a state where the low-temperature plasma hydrogen-containing gas is in contact therewith under atmospheric pressure. Sample analysis method.

13. An analysis apparatus for a sample made of metal, comprising: The plasma generation unit and the gas supply unit according to any one of claims 6 to 9, and (c) an analysis unit that analyzes the surface in a state where the low-temperature plasma hydrogen-containing gas is in contact therewith under atmospheric pressure. Sample analysis apparatus.

14. An analysis apparatus for a sample made of metal, comprising: The plasma generation unit and the gas supply unit according to claim 10, and (c) an analysis unit that analyzes the surface in a state where the low-temperature plasma hydrogen-containing gas is in contact therewith under atmospheric pressure. Sample analysis apparatus.

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