JP3443191B2 - Method of forming sample body used in sample analysis method by heating - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION This invention is related to the shape forming method of a sample material used in the sample analysis process by heating.

[0002]

_2. Description of the Related Art For example, Y ₂ O ₃ (yttrium oxide)
Analysis of O (oxygen) contained in oxides such as and N (nitrogen) contained in nitrides such as Si ₃ N ₄ (silicon nitride) is generally performed as follows. That is, a graphite crucible is set between a pair of electrodes in a sample extraction furnace placed in an airtight manner, and the oxide or nitride is put into the graphite crucible as a sample, and an inert gas such as Ar (argon) is added. While supplying a gas as a carrier gas into the sample extraction furnace, a large current is passed between the electrodes to electrically melt the sample in the graphite crucible, and the gas generated at that time is guided to an analyzer to determine the gas concentration based on the gas concentration. The element is quantitatively analyzed.

By the way, the oxides and nitrides used as the samples are often in the form of powder or particles,
Therefore, conventionally, it has been as shown in FIGS. That is, first, a bottomed cylindrical container made of nickel as shown in FIG.
(Outer diameter 5.0 mm, thickness 0.2 mm, height 10 mm, weight 0.3 g or outer diameter 6.5 mm, thickness 0.2 mm, height 13 mm, weight 0.5 g, etc.) 22 is stored in an amount of 10 to 30 mg.

Next, in order to minimize the influence of errors due to oxygen and nitrogen in the air and to keep the reaction conditions during melting constant, the container 21 containing the sample 22 is pressed in the diametrical direction, As shown in FIG. 5B, a flat sample body 21A is formed. Thereafter, the flat sample body 21A was molded into a cylindrical sample body 21B as shown in FIG. 6 by using an appropriate tool 23 such as pliers so that it could be easily housed in the graphite crucible 24.

Then, in the analysis, the sample body 21 is adjusted so that the amount of gas generated by the melting reaction is maximized in a short time.
Select B, and if necessary, diameter 3mm, thickness 2m
A nickel disc of m was added to perform the analysis.

[0006]

However, as described above, when the powder sample 22 is enclosed in the cylindrical container 21, both pressing and molding of the container 21 must be performed. Conventionally, the sample body 21A having a different shape or the flat sample body 21A is molded into a cylindrical sample body 21B by using the pliers 23 or the like, conventionally. For this reason, due to the skill and skill of the person who forms the sample body, the shape of the formed sample body is often distorted or irregular.

[0007] For example, in order to perform a highly accurate analysis such as a coefficient of variation (Cv) of 0.2% for an oxygen-containing material of 21%, it is required that the sample bodies have the same shape. the form forming method of the conventional sample, it is difficult to satisfy this requirement.

The present invention has been made with the above matters in mind, and its purpose is to require no skill or skill.
Always it is possible to form a sample of a certain shape is to provide Hisage shape forming method of a sample for use in sample analysis method by heating.

[0009]

In order to achieve the above object, the method for forming a sample body used in the sample analysis method by heating according to the present invention is such that a powder is placed in a cylindrical container whose upper part is open and whose lower part is closed. After accommodating a sample in the form of particles or granules, the lid main body having a diameter slightly smaller than the inner diameter of the container, a vertical portion formed by bending the peripheral end portion upward by an appropriate amount, and the upper end side of the vertical portion. A lid body formed by bending outward and having a diameter larger than the outer diameter of the container and held by the peripheral edge of the opening of the container is provided. It is characterized in that it is placed in a dropped state, and in that state, a pressing force in the vertical direction is applied to the container to form a flat sample body in which the upper opening of the container is closed by a lid.

[0010]

[0011]

By the shape forming method of action The sample body lever, it is possible to perform pressing and molding of the container at the same time in a state of accommodating the powdery or granular form of the sample, the precision of the container required for high-precision analysis Squeezing can be easily performed, and a sample body having a constant shape can always be easily obtained.

[0012]

1 to 4 show an embodiment of the present invention,
First, in FIGS. 1 and 2, 1 is a bottomed cylindrical container having an open upper part and a closed lower part, 2 is a powdery sample contained in the container 1, and 3 is a container containing the sample 2. It is a lid that closes the upper opening 4 of 1.

More specifically, the container 1 and the lid 3
Is made of, for example, high-purity nickel. The container 1 has, for example, an outer diameter of 3 to 15 mm, an inner diameter of 2 to 10 mm,
The depth is about 1 to 10 mm. The lid 3 has a lid body 5 having a diameter slightly smaller than the inner diameter of the container 1 (for example, smaller than the inner diameter by 0.1 to 5 mm).
And a vertical portion 5 formed by bending the peripheral end portion upward by an appropriate dimension (for example, about 0.1 to 5 mm), and an upper end side of the vertical portion 6 is bent outward to form a container. Opening peripheral end 7 of 1
Locking portion 8 held by (1 to 6 from the outer diameter of the container 1
mm larger).

Reference numeral 9 is a jig composed of a lower mold 10 and an upper mold 11, and these molds 10 and 11 are made of, for example, stainless steel. The lower die 10 is, for example, a columnar block, and a recess 12 having a dish shape in cross section is formed at substantially the center of its upper surface. In addition, the upper mold 11 has a recess 13 having an inverted dish shape in cross section, which is formed substantially at the center of the lower surface, that is, at a position corresponding to the recess 12 of the lower mold 10, and the lower part is formed around the lower surface. A guide portion 14 having a diameter slightly larger than that of the mold 10 is provided so as to hang down.

Then, the lower die 10 and the upper die 11
The recesses 12 and 13 respectively formed in the are for preventing the container 1 and the lid body 3 from being displaced when the container 1 and the lid body 3 are pressed. Then, the recess 1 of the lower mold 10
2 is almost the same size as the outer diameter of the container 1. Further, the dimensions of each of the concave portions 13 of the upper mold 11 are such that the small diameter portion (upper bottom side) has substantially the same diameter as the outer circumference of the container 1 and the large diameter portion (opening side).
Is larger than the small diameter portion by about 1 to 6 mm, and the depth is about 0.2 to 5 mm.

Next, a procedure for forming a sample body by using the jig 9 having the above structure will be described with reference to FIG. As shown in FIG.
Is fixed on the bed 16 of the press 15 so that the upper part is on the upper side, and the upper mold 11 is fixed on the slide 17 of the press 15 such that the concave part 13 is on the lower side. In that case, the lower die 10 is aligned so that it is located in the guide portion 14 of the upper die 11. Powder sample 2
Is weighed and stored in the container 1 in a fixed amount. Figure 3 (A)
As shown in, the container 1 containing a predetermined amount of the sample 2 is placed in the recess 13 of the lower mold 11, and the lid 3 is placed so as to cover the upper opening 4 of the container 1. The slide 17 is lowered, and the upper mold 11 is pressed toward the lower mold 10 with a pressing force of, for example, about 50 to 700 kg / cm ² (see FIGS. 3B and 3C). When the slide 17 is raised and the pressure is released, a flat (disc-shaped) sample on the lower mold 10 in which the upper opening 4 of the container 1 is closed by the lid 3 as shown in FIG. 3 (D). A body S is formed.

In this embodiment, the lid 3 for closing the upper opening 4 of the container 1 in a hermetically sealed state is such that the lid body 5 having a diameter slightly smaller than the inner diameter of the container 1 and the peripheral end portion thereof are bent upward by an appropriate amount. It is composed of a bent vertical portion 6 and a locking portion 8 formed by bending an upper end side of the vertical portion 6 outward and held by an opening peripheral end portion 7 of the container 1. When the container 1 is covered with such a lid 3 and the both members 1 and 3 are sandwiched by an appropriate pressing force, the opening peripheral end portion 7 of the container 1 and the locking portion 8 of the lid 3 are plural. In close contact, and in Fig. 3
As shown in (C) and (D), the locking portion 8 has the opening peripheral end portion 7
Both of them are bent so that they are in close contact with each other. Therefore, the lid 3 and the container 1 are in close contact with each other, the lid 3 is disengaged from the container 1 after pressing with a press, or a gap is generated between the container 1 and the lid 3, so that the sample 2 in the container 1
A completely sealed sample body S in which the water does not leak out is completed (see FIG. 3C).

Further, in the jig 9 of this embodiment, since the recesses 12 and 13 are formed on the upper surface of the lower mold 10 and the lower surface of the upper mold 11, respectively, the container 1 and the lid 3 are separated from each other. It is possible to surely clamp both members 1 and 3 without being displaced. In particular, since the tapered surface 13a is formed in the concave portion 13 of the upper mold 11, the locking portion 8 of the lid 3 can be surely bent inward.

According to the sample forming method of the above-described embodiment, the container 1 can be pressed and molded at the same time while the powdery sample 2 is accommodated therein, and the sample body S having a constant shape can always be easily formed. Obtainable. Then, the sample material S formed in this manner, as shown in FIG. 4, a graphite crucible 18
It can be stored in a stationary state on the inner bottom surface of the
Different from the case shown in. Therefore, the sample body S according to this example is heated efficiently and evenly.

Using the sample body S described above, a nitrogen content of 39
% Si ₃ N ₄ was analyzed, and the results shown in Table 1 below were obtained.

[0021]

[Table 1]

Conventionally, the coefficient of variation has a large variation of 0.20 to 0.60% due to the above-mentioned human error, but as can be understood from Table 1 above, the coefficient of variation is 0.2.
It has become possible to keep it below%.

In the analysis of Y ₂ O ₃ , the results shown in Table 2 below were obtained.

[0024]

[Table 2]

According to the present invention, unlike the prior art, the coefficient of variation due to human error is greatly improved, and therefore, it is possible to greatly contribute to higher precision sample analysis.

According to the present invention, the preparation of the sample body S is significantly shortened as compared with the prior art. For example, in the conventional analysis, the weighing time of the sample 2 is about 1 to 3 minutes and the sample body S is about 3 minutes. the creation time 3-5 minutes, although the analysis time was 3 minutes, according to the present invention, only the creation time of the sample bodies S 1
I can do it in 0 seconds.

The present invention is not limited to the above-mentioned embodiments, but can be implemented by being modified in various ways.
Either the upper surface of the lower mold 10 or the lower surface of the upper mold 11 may be flat. Further, when the container 1 is made of high-purity nickel, nickel is stable against oxygen and nitrogen, so that highly accurate measurement is possible.
The container 1 may be made of iron. The analysis sample may be in the form of particles.

[0028]

As described above, according to the present invention, it is possible to always form a sample body of a fixed shape without requiring skill and skill, and to close the lid with respect to the container with good sealing performance. Since it can be pressure-welded, there is no inconvenience that the sample contained in the container leaks out, and therefore,
The sample analysis by heating can be performed with high accuracy and reproducibility.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view showing an example of an apparatus for carrying out the method of the present invention.

FIG. 2 is a vertical cross-sectional view showing a main part of the device.

FIG. 3 is an explanatory diagram showing an example of steps for carrying out the method of the present invention.

FIG. 4 is a vertical cross-sectional view showing a state in which the sample body is housed in a graphite crucible.

FIG. 5 is a diagram for explaining a conventional method.

FIG. 6 is a longitudinal sectional view showing a state in which a sample body obtained by a conventional method is housed in a graphite crucible.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Container, 2 ... Sample, 3 ... Lid body, 4 ... Upper opening, 5 ... Lid main part, 6 ... Vertical part, 7 ... Opening peripheral end part, 8 ... Locking part, 1
0 ... Lower mold, 11 ... Upper mold, 12, 13 ... Recess, S
… Sample body.

Front Page Continuation (72) Inventor Michiko Kurita 2 Higashimachi, Kichijoin Miya, Minami-ku, Kyoto City, Kyoto Prefecture (56) References JP-A-49-91926 (JP, A) JP-A-6-341936 (JP, A) JP-A-6-201535 (JP, A) Actually open Sho 59-106698 (JP, U) Actually open Sho 59-115339 (JP, U) Japanese Patent Sho 57-27418 (JP, B2) Special Kohei 5-11262 (JP, B2) Japanese Patent Kohei 5-13569 (JP, B2) Actual Kohei 3-256 (JP, Y2) JIII Journal of Technical Disclosure No. 88-2720 (58) Fields investigated ( Int.Cl. ⁷ , DB name) G01N 1/00-1/44 G01N 25/00-25/72 G01N 31/00-31/22 JISST file (JOIS)

Claims (2)

(57) [Claims] 1. A lid main body having a diameter slightly smaller than the inner diameter of the container and a peripheral end portion thereof after accommodating a powdery or granular sample in a cylindrical container having an open upper part and a closed lower part. A vertical part formed by bending the upper part of the container to an appropriate size, and an upper end side of the vertical part bent outward, and a lock that is larger than the outer diameter of the container and is held by the peripheral edge of the opening of the container. Place the lid body consisting of the part and the lid body part inside the container opening, and in that state, apply a vertical pressing force to the container and close the top opening of the container with the lid. A method for forming a sample body for use in a sample analysis method by heating, which comprises forming a simple sample body. 2. The method for forming a sample body used in the sample analysis method by heating according to claim 1, wherein the container and the lid are made of nickel or iron.