KR101681290B1 - Method for determining uniformity and method for measuring density from amorphous metal using ultra small angle neutron scattering - Google Patents
Method for determining uniformity and method for measuring density from amorphous metal using ultra small angle neutron scattering Download PDFInfo
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Abstract
Description
There is provided a method of measuring uniformity and density from a rough surface of an amorphous metal using neutron ultrafine scattering.
BACKGROUND ART Bulk metallic glass refers to a material which is homogeneous in the interior of a material and is made only of an amorphous phase without crystal regions, particle interfaces, or dislocations. Whether or not the amorphous phase has only a homogeneous phase can be confirmed at an atomic level, for example, 1 nm or less through x-ray diffraction (XRD) or electron microscopy .
In addition, non-uniformities in structures from about 1.0 nm to about 100 nm larger than the atomic level are measured by small angle x-ray scattering (SAXS) or small angle neutron scattering (SANS) .
However, the measurement method of x-ray small angle scattering and neutron small angle scattering can not measure the nonuniformity in the ㎛ unit structure.
In the case of x-ray incineration, a mechanical polishing process is required to thin the sample to a few microns because of the large x-ray absorption of the metal sample. The pressure, heat, or shearing stress the structure of the amorphous material may be deformed or broken by a force. In addition, since the measured sample area is as small as several microns to several hundreds of microns, there is a possibility that a heterogeneous image may be misinterpreted as a homogeneous image if density or size distribution of heterogeneity exists.
On the other hand, in the neutron small angle scattering measurement method, the majority of the amorphous material can be manufactured, for example, in the form of a thin ribbon. At this time, the roughness of the surface of the cold roll that winds the ribbon can be transferred to the surface of the amorphous ribbon. Specifically, when the uniformity of the amorphous material is measured by a small angle scattering measurement method, the surface of the amorphous ribbon may have a rough shape from the nano size to a microscopic size that can be visually recognized, Scattering on a rough surface can be overwhelmingly larger than scattering on a surface. Therefore, despite the fact that the structure of the amorphous phase is actually uniform, it is possible to cause an error in data interpretation due to scattering on the surface due to nonuniform structure.
For example, in the case of polishing in order to minimize the influence of the surface in the measurement method of the neutron small angle scattering, polishing in the nature of the product, such as when it is used in a surgical instrument, sporting goods, or a sensor, Surface finishing may be required [A. Gebert, F. Gostin, U. Kuhn, L. Schultz, ECS Transactions 16 (32), (2009) 1-7]. As a result, roughness may occur on the surface, and scattering of the rough surface may cause errors in the measurement of uniformity.
For example, in the case of an amorphous metal containing Zr, an oxide film (ZrO 2 ) due to oxygen may be generated. Since such an oxide film may affect the physical / mechanical properties of the amorphous metal, And the roughness of the polished surface can be determined depending on the material of the abrasive or the polishing method. As a result, data errors may occur in the uniformity measurement.
One embodiment of the present invention is to efficiently remove the scattering due to the rough surface of the amorphous metal to efficiently determine the uniformity of the interior of the amorphous metal, the presence of pores, and the density value.
Embodiments according to the present invention can be used to accomplish other tasks not specifically mentioned other than the above-described tasks.
A method for measuring uniformity and density from a rough surface of an amorphous metal using neutron ultrafine scattering according to an embodiment of the present invention includes preparing an amorphous metal material, preparing a mixed solvent containing two or more liquids, Measuring the scattering intensity of the mixed solvent using an ultra small angle neutron scattering instrument (USANS); preparing a sample by adding an amorphous metal material to the mixed solvent; Adjusting the concentration ratio of two or more liquids contained in the mixed solvent so that the scattering intensity of the mixed solvent and the scattering intensity of the sample have the same value, and determining the uniformity of the amorphous metal material .
The surface of the amorphous metal material may have roughness.
The mixed solvent may be a mixture of a liquid containing hydrogen (H) and a liquid containing deuterium (D).
In the step of adjusting the concentration ratio of two or more liquids, the concentration ratio of the liquid containing hydrogen to the liquid containing deuterium such that the scattering length density value of the mixed solvent has the same value as the scattering length density value of the amorphous metal material Can be adjusted.
The mixed solvent may be a mixture of hydrogenated ethanol (C 2 H 5 OH) and deuterated ethanol (C 2 D 5 OD).
The mixed solvent may be a mixture of water (H 2 O) and heavy water (D 2 O).
And determining a density value of the amorphous metal material after the step of determining the uniformity of the amorphous metal material.
The density value of the amorphous metal material can be obtained from the following equation.
[Mathematical Expression]
In the equation, ρ denotes the density value of the amorphous metal material, i denotes the component of the amorphous metal material, n denotes the number of components contained in the amorphous metal material as a natural number, SLD CM denotes the scattering intensity of the sample, scattering intensity represents a scattering length density of the mixed solvent of the same case, N a denotes the Avogadro's number, f i denotes the fraction of the component i comprises the amorphous metallic material, M i is contained in the amorphous metal material Represents the molecular weight of component i, and b i can represent the neutron scattering length of the component contained in the amorphous metal material.
A step of preparing an amorphous metallic material may further include the step of heat treatment at a temperature lower than the glass transition temperature (T g) of the amorphous metal material.
The step of preparing the amorphous metal material may further comprise polishing the surface of the amorphous metal material.
The method of measuring the uniformity and density from the rough surface of the amorphous metal by using the neutron ultrafine scattering according to an embodiment of the present invention effectively removes the scattering due to the rough surface of the amorphous metal, Inclusive, and density values.
Fig. 1 shows a basic configuration of a general micro-angle neutron scattering apparatus.
2 is a flow chart illustrating a method for measuring uniformity and density from a rough surface of an amorphous metal using neutron ultrafine scattering according to embodiments.
3A shows the neutron scattering when the sample contains only amorphous metal with smooth surface.
Figure 3b shows the neutron scattering when the sample contains only amorphous metal with rough surface.
FIG. 3C shows the neutron scattering when the sample contains an amorphous metal having a mixed solvent and a rough surface, and the scattering length density of the mixed solvent and the scattering length density of the amorphous metal are the same.
FIG. 3D shows neutron scattering in the case where the sample contains a mixed solvent and a metal material having a rough surface, the scattering length density of the mixed solvent is the same as the scattering length density of the metal, and the metal interior is a nonuniform phase.
FIG. 3E shows the neutron scattering when the sample contains an amorphous metal material having a mixed solvent and a rough surface, the scattering length density of the mixed solvent is equal to the scattering length density of the metal, and bubbles are contained in the amorphous metal .
4A is a photograph of the amorphous metal (Cu 50 Zr 50 ) before polishing of Example 1, and FIG. 4B is a photograph of amorphous metal (Cu 50 Zr 50 ) after polishing of Example 1. FIG.
5 is a graph showing an x-ray diffraction pattern of (a) before heat treatment and (b) after heat treatment in Example 1. Fig.
FIG. 6A is a graph showing neutron ultrafine scattering of amorphous metal (Cu 50 Zr 50 ) of Example 1 in hydrogenated ethanol (C 2 H 5 OH).
6B is a graph showing neutron micro-angle scattering of amorphous metal (Cu 50 Zr 50 ) of Example 1 in deuterated ethanol (C 2 D 5 OD).
FIG. 6c is a graph showing the neutron micro scattering of amorphous metal (Cu 50 Zr 50 ) of Example 1 in hydrogenated ethanol (C 2 H 5 OH) and deuterated ethanol (C 2 D 5 OD).
7 is a graph showing the relationship between the square root value of Q Inv (Q) of Example 2 and the concentration ratio of deuterated ethanol (C 2 D 5 OD) in a mixed solvent.
BRIEF DESCRIPTION OF THE DRAWINGS The above and other features and advantages of the present invention will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: FIG. The present invention may be embodied in many different forms and is not limited to the embodiments described herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and the same reference numerals are used for the same or similar components throughout the specification. In the case of publicly known technologies, a detailed description thereof will be omitted.
In the drawings, the thickness is enlarged to clearly represent the layers and regions. It will be understood that when an element such as a layer, film, region, plate, or the like is referred to as being "on" another portion, it includes not only the element directly over another element, On the other hand, when a part is "directly on" another part, it means that there is no other part in the middle. On the contrary, when a portion such as a layer, film, region, plate, or the like is referred to as being "under" another portion, this includes not only the case where the other portion is "directly underneath" On the other hand, when a part is "directly beneath" another part, it means that there is no other part in the middle.
Throughout the specification, when an element is referred to as "comprising ", it means that it can include other elements as well, without excluding other elements unless specifically stated otherwise.
Hereinafter, a method for measuring the uniformity and density from the rough surface of the amorphous metal using the neutron ultrafine scattering according to the embodiments will be described in detail.
FIG. 1 shows a basic configuration of a conventional ultra small angle neutron scattering instrument. The micro-angle neutron scattering apparatus may be, for example, a Bonse-Hart-Agamalian (BHA) type apparatus, which is illustrated for convenience of explanation, A scattering device can be used. Such a micro-angle neutron scattering apparatus is a device for nondestructively measuring the structure of a material up to micron size using neutrons.
Neutrons have very low energy compared to x-rays or electron beams, and do not cause damage or change due to energy in the target material. The material permeability is very high and the internal structure of the material can be easily observed. It is possible to measure solid and liquid samples under various experimental conditions without artificial environmental constraints such as vacuum required.
In addition, neutrons are scattered by interacting with nuclei, so even if they have the same atomic number, they can show very different scattering characteristics if the atomic masses are different. For example, hydrogen (H) with one proton and deuterium (D), which has one proton and one neutron, have different scattering properties. Therefore, since the solvent (e.g., C 2 H 5 OH) containing H and the solvent (for example, C 2 D 5 OD) containing D, which is an isotope thereof, do not greatly differ in physical / By properly adjusting the mixing ratio of the solvent, the neutron scattering contrast can be varied while maintaining the physical / chemical properties of the sample.
Referring to FIG. 1, a typical micro-angle neutron scattering apparatus includes a
The method of measuring the uniformity and density from the rough surface of the amorphous metal by using the neutron ultrafine scattering according to the embodiments can eliminate the scattering due to the rough surface of the amorphous metal to more accurately determine whether the inside of the target material is uniform It can be judged. This makes it possible to prevent errors in the interpretation of measurement results due to scattering on the surface.
If it is determined that the interior of the subject material is uniform, the density value of the subject matter can be determined therefrom. On the other hand, when it is judged that the interior of the object substance is uneven, it can be assumed that the substance contains pores. This will be described in detail below.
On the other hand, in the case of the conventional x-ray small angle scattering (SAXS) method or the neutron small angle scattering (SANS) method, nonuniformity in a relatively small area such as a nanometer size can be judged. On the other hand, through the method of measuring the uniformity and the density from the rough surface of the amorphous metal by using the neutron ultrafine scattering according to the embodiments, it is possible to determine uniformity in a relatively large area such as a micro (탆) size It can be judged.
However, the method of measuring the uniformity and the density from the rough surface of the amorphous metal by using the neutron ultrafine angle scattering in the embodiments may use other neutron scattering apparatus in addition to the BHA-type micro Angular Neutron scattering apparatus of FIG. 1, It should be noted that an x-ray source may be used instead of a circle.
Hereinafter, the method for determining whether the amorphous metal having a rough surface has uniformity, density, and pores according to embodiments will be described in detail.
2 is a flow chart illustrating a method for measuring uniformity and density from a rough surface of an amorphous metal using neutron ultrafine scattering according to embodiments.
Referring to FIG. 2, a method for measuring uniformity and density from a rough surface of an amorphous metal by using a neutron ultrafine angle scattering includes preparing an amorphous metal material, preparing a mixed solvent containing two or more liquids, Measuring the scattering intensity of the mixed solvent using each scattering apparatus, measuring the scattering intensity of the sample using a neutron micro-scattering apparatus after preparing a sample by adding an amorphous metal material to the mixed solvent, Adjusting the concentration ratio of two or more liquids contained in the mixed solvent so that the scattering intensity of the mixed solvent and the scattering intensity of the sample have the same value, and obtaining the density value of the amorphous metal material.
Specifically, a step of preparing an amorphous metal material is performed first. An amorphous metal material refers to a material which is made of amorphous phase without a crystalline region, a grain boundary, or a dislocation, because the inside of the material is uniform. The amorphous metal material may include, for example, copper (Cu) and zirconium (Zr). Such an amorphous material can be produced in the form of a ribbon.
In addition, the amorphous metal material may have a predetermined roughness on the surface during the preparation of transferring or polishing of the surface of the cooling roll. Such roughness causes scattering on the surface, scattering intensity of the scattered light.
On the other hand, the step of preparing the amorphous metal material may further include a step of heat-treating the amorphous metal material at a temperature lower than the glass transition temperature (Tg) of the amorphous metal material. The internal structure of the amorphous metal material can be made more uniform through heat treatment.
Further, the step of preparing the amorphous metal material may further include the step of polishing the surface of the amorphous metal material. By polishing the surface of the amorphous metal material, it is possible to remove the oxide film on the surface which may occur during the preparation of the material and make the surface uniform in roughness. The polishing of the surface can be performed by, for example, a polishing material such as sandpaper, but is not limited thereto.
Next, a mixed solvent containing two or more liquids is prepared, and a mixed solvent is put into the
Here, the mixed solvent may be a mixture for mixing a liquid containing hydrogen (H) and a liquid containing deuterium (D). Hydrogen (H) and deuterium (D) may have different scattering properties in the measurement of the scattering intensity by the neutron ultrafine scattering device.
For example, the mixed solvent may be a mixture of hydrogenated ethanol (C 2 H 5 OH) containing hydrogen (H) atoms and deuterated ethanol (C 2 D 5 OD) containing deuterium (D) atoms.
Further, for example, the mixed solvent may be water (H 2 O) containing hydrogen (H) and heavy water (D 2 O) containing deuterium (D) which is an isotope of hydrogen have.
The following Examples 1 and 2 focus on mixed solvents in which hydrogenated ethanol (C 2 H 5 OH) and deuterated ethanol (C 2 D 5 OD) are mixed, but water (H 2 O ) And heavy water (D 2 O) are mixed.
In addition, the mixed solvent according to the embodiments is not limited thereto, and may be a liquid containing hydrogen (H) and an organic solvent containing deuterium (D).
The mixed solvent is composed of two or more liquids which are uniform, and the scattering intensity (I (Q) liquid ) can be measured. This is the reference scattering intensity (I (Q) liquid ) in the method of measuring the uniformity and density from the rough surface of the amorphous metal using the neutron ultrafine scattering according to the embodiments. In embodiments, the reference scattering intensity I (Q) liquid may be, for example, the scattering intensity of the mixed solvent.
Thereafter, the amorphous metal material is mixed with the mixed solvent to prepare a sample, and the sample is drawn into the
In the present specification, the sample refers to a mixture of an amorphous metal material and a mixed solvent.
As a result of the measurement, if the reference scattering intensity I (Q) liquid and the sample scattering intensity I (Q) sample are the same, it can be assumed that the amorphous metal has a uniform interior and does not contain pores , From which the density value can be determined.
On the other hand, when the reference scattering intensity I (Q) liquid and the sample scattering intensity I (Q) sample do not match, the scattering intensity I (Q) liquid of the mixed solvent and the scattering intensity I (Q) sample ) have the same value by controlling the concentration ratio of two or more liquids contained in the mixed solvent.
If the reference scattering intensity (I (Q) liquid ) and the scattering intensity (I (Q) sample ) of the sample do not match even though the neutron scattering of the sample is measured repeatedly by controlling the concentration ratio, It can be estimated that pores exist. In addition, if the surface polishing of the amorphous metal is not performed, the scattering intensity may be inconsistent due to the oxide film existing on the surface.
However, if the concentration ratio of two or more liquids contained in the mixed solvent is repeatedly adjusted and the reference scattering intensity I (Q) liquid and the scattering intensity I (Q) sample of the sample coincide with each other, You can estimate the property and calculate the density value.
On the other hand, the scattering intensity I (Q) sample of the sample is proportional to the square of the scattering length density difference of the two phases, as shown in the following equation (1). Here, the two phases mean a case where the sample is composed of two materials, or a case where the interior of one material is composed of a non-uniform phase.
[Equation 1]
I (Q)? (SLD i - SLD j ) 2
In Equation (1), Q is a scattering vector. When the element i and the element j are uniformly mixed, only noise due to the environment or incoherent scattering can be measured at a constant value regardless of the scattering vector Q. Therefore, if neutron ultrafine scattering is measured on a specimen composed of only amorphous metal with a uniform phase, neutron intensity corresponding to ambient noise or non-interference scattering can not be measured.
In order to measure the scattering intensity, the substance to be measured should be within the range of measurable by the micro-angle scattering and should include at least two phases. As can be seen from Equation (1), in order to measure the I (Q) sample , which is the scattering intensity different from the scattering intensity I (Q) liquid of the mixed solvent from the sample , (SLD), which is the difference in neutron scattering length density (SLD).
If only the reference scattering intensity (I (Q) liquid ) corresponding to the mixed solvent is detected through the measurement of the sample, it can be judged that the inside of the amorphous metal is made into the same phase. On the other hand, if an intensity different from the reference scattering intensity I (Q) liquid is detected in the
However, when the amorphous metal having a single phase inside has a surface with roughness, scattering occurs at the surface, and a scattering intensity different from the reference scattering intensity I (Q) liquid can be detected. Also, even in the presence of pores inside or on the surface of the amorphous metal, a scattering intensity different from the reference scattering intensity (I (Q) liquid ) can be detected due to scattering due to this. Therefore, errors in the determination of uniformity due to scattering intensity measurement may occur.
At this time, if the scattering length density of the mixed solvent and the scattering length density of the amorphous metal material match, the mixed solvent can function to smoothen the rough surface of the amorphous metal material. In this case, when the scattering intensity is measured with respect to the amorphous metal having a single phase inside, only the scattering intensity (I (Q) liquid ) of the mixed solvent can be detected since the scattering density difference does not occur. However, even in this case, if pores are present in the amorphous metal, a value different from the reference scattering intensity (I (Q) liquid ) can be measured.
The measurement of the scattering intensity will be described in more detail with reference to FIGS. 3A to 3E.
FIG. 3A shows a case where the sample does not contain a mixed solvent and contains only amorphous metal having a smooth surface. In this case, the scattering density difference corresponding to the amorphous metal can not be measured in the
FIG. 3B shows a case where the sample does not contain a mixed solvent and the surface contains only amorphous metal having roughness. In this case, when neutron ultrafast scattering measurement is performed, a scattering intensity different from the reference scattering intensity corresponding to the surrounding medium can be detected. This is because even if an amorphous metal having a uniform phase is formed, neutron scattering due to the surface may occur.
FIG. 3C shows the case where the sample contains both the mixed solvent and the rough amorphous metal on the surface, and the scattering length density of the mixed solvent and the scattering length density of the amorphous metal are the same. In this case, since the mixed solvent fills the rough portion of the amorphous metal surface to smooth the surface, only the scattering intensity (I (Q) liquid ) corresponding to the mixed solvent can be detected. It can therefore be deduced that the interior of the amorphous metal has a uniform composition.
FIG. 3D shows a case where the sample contains both the mixed solvent and the surface-roughened metal material, and the scattering length density of the mixed solvent and the scattering length density of the metal are the same. In this case, as a result of the scattering measurement, a scattering intensity different from the scattering intensity (I (Q) liquid ) corresponding to the mixed solvent is detected, and it is estimated that there are two or more phases in the metal material, can do.
FIG. 3E shows a case where the sample contains both the mixed solvent and the surface amorphous metal material, and the scattering length density of the mixed solvent and the scattering length density of the amorphous metal are the same. However, as a result of the scattering measurement, a scattering intensity different from the scattering intensity (I (Q) liquid ) corresponding to the mixed solvent can be detected, and it can be assumed that pores exist in the inside or the surface of the amorphous metal material.
In summary, the method of measuring the uniformity and density from the rough surface of the amorphous metal by using the neutron ultrafine scattering is to remove the neutron scattering caused by the rough surface which may occur during the preparation of the amorphous metal material, Can be prevented. It can be assumed that the internal structure of the amorphous metal is uniform if the scattering length density is matched with the scattering length density of the amorphous metal through the control of the concentration ratio of the chemically identical mixed solvent containing hydrogen and deuterium. On the other hand, if the concentration ratio control process is repeated several times, if there is no difference in scattering length density, it can be estimated that the internal structure of the amorphous metal is uneven, the pores are present in the interior, or the oxide film exists on the surface.
When the scattering intensity of the mixed solvent and the scattering intensity of the sample have the same value, the density value of the amorphous metal can be obtained by the following equation (2).
&Quot; (2) "
In the equation, ρ denotes the density value of the amorphous metal material, i denotes the component of the amorphous metal material, n denotes the number of components contained in the amorphous metal material as natural numbers, SLD CM denotes the scattering intensity of the sample, Wherein A represents the scattering length density of the mixed solvent when the scattering intensity of the solvent is the same, N A represents the number of Avogadro, f i represents the fraction of component i contained in the amorphous metal material, and M i is included in the amorphous metal material B i represents the neutron scattering length of the component contained in the amorphous metal material.
Meanwhile, in the method of measuring the uniformity and the density from the rough surface of the amorphous metal by using the neutron ultrafine scattering according to the embodiments, the step of adjusting the concentration ratio of the mixed solvent may be performed by other methods .
Specifically, the value of the scattering intensity (I (Q) sample ) of a sample mixed with an amorphous metal in a mixed solvent is converted into an invariant Q Inv (Q) (unit: A -3 cm -1 ). Here, Q Inv (Q) represents the area of the graph when I (Q) Q 2 and Q are expressed in a graph in Equation (3). Q min and Q max are the scattering vectors at the beginning and end of the scattering intensity measured.
&Quot; (3) "
Referring to Equation (4), the square root value of Q Inv (Q) is proportional to the difference between the scattering length density of the amorphous metal material and the scattering length density of the mixed solvent.
&Quot; (4) "
Where i may be an amorphous metal material and j may be the scattering length density of the mixed solvent.
At this time, a graph is shown with the square root value of Q Inv (Q) as the y axis and the volume ratio of deuterated ethanol as the x axis, and the square root of the Q Inv (Q) You can move some of the values to a negative value and flip them along the x-axis. For example, of the square root values of Q Inv (Q) having a positive value, values that are closest to the linearity can be selected when the x axis is symmetric.
A graph by this method is shown in Fig. Referring to FIG. 7, in the linear graph, the point at which the square root value of Q Inv (Q) becomes zero is the mixture concentration ratio of the mixed solvent in which the scattering length density of the sample and the scattering length density of the mixed solvent are coincident The concentration ratio of the solvent).
In addition, the density of the amorphous metal material can be obtained by substituting the scattering length density (SLD CM ) of the mixed solvent having the concentration ratio using the linear graph into the equation (2).
When the method using the linear graph is used, the concentration ratio of the mixed solvent can be obtained more easily than the method of controlling the concentration ratio repeatedly, and a more accurate value can be obtained.
However, in the case where the linear graph as shown in FIG. 7 is not formed, it can be predicted that it is due to the oxide film or the pores formed on the surface of the amorphous metal. Also, if a linear graph is not formed after removing the oxide film on the surface, it can be understood that this is due to non-uniformity such as precipitates or impurity particles in the amorphous metal, or due to pores.
EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples. However, the following Examples are merely examples of the present invention, but the present invention is not limited to the following Examples.
Example 1
In order to make the internal structure of the amorphous metal Cu 50 Zr 50 (20 mm in width, 0.05 mm in thickness) shown in FIG. 4 a more uniform, annealing (annealing) was performed for 1 hour under a vacuum condition and a temperature of 400 ° C. lower than the glass transition temperature )do. The x-ray diffraction results are shown in Fig.
Referring to FIG. 5, in Example 1, the scattering intensity (intensity) before and after the heat treatment in the atomic unit (FIG. 5A and FIG. 5B) is approximately the same curve. From this, it can be inferred that amorphous metal without heat treatment can be used in the case of this embodiment.
On the other hand, in order to remove the oxide film on the surface which may occur in the preparation process and to make the surface uniform in roughness, the amorphous metal is polished with sandpaper No. 2000 (see FIG. 4B). The size of the sandstone particles is approximately 10.3 ㎛ (error can be about 0.8 ㎛), which is within the range of neutron ultrafast scattering measurement method, which can be advantageous for neutron ultrafast scattering measurement.
After polishing the sandpaper, the ribbon-shaped amorphous metal is washed with acetone, and then three amorphous metals are laid over the sample cell.
As a solvent for contacting the surface of the amorphous metal, ethanol having a small surface tension is used in contact with the surface of the amorphous metal. Specifically, ethanol uses hydrogenated ethanol (C 2 H 5 OH, ethanol-h) containing hydrogen atoms and deuterated ethanol (C 2 D 5 OD, ethanol-d) containing deuterium.
On the other hand, even if neutron microscopic scattering is measured by immersing amorphous metal in a mixed solvent in which water (H 2 O) and heavy water (D 2 O) having relatively large surface tension are mixed, the same results can be obtained within the experimental error.
Table 1 below shows the scattering length density (SLD) of hydrogenated ethanol, deuterated ethanol and mixed solvents. As shown in Table 1, the hydrogenated ethanol has a negative SLD value, and the deuterated ethanol has a positive SLD value, so that the SLD value is equal to the scattering length density of the amorphous metal sample To prepare a mixed solvent.
Specifically, the scattering intensity of the mixed solvent is measured using a neutron ultrafine scattering apparatus, and then the scattering intensity of the sample in which the amorphous metal material is mixed with the mixed solvent is measured, and the two values are compared. As a result of comparison, if the scattering intensity of the mixed solvent and the scattering intensity of the sample mixed with the amorphous metal coincide with each other, it can be determined that the inside of the amorphous metal is uniform, and the density of the amorphous metal can be calculated. On the other hand, when the two scattering intensities are inconsistent, the scattering intensities are compared by adjusting the mixing ratio (concentration) of the solvents constituting the mixed solvent.
The concentration ratios of hydrogenated ethanol and deuterated ethanol were mixed at 100: 0, 60:40, 20:80, and 0: 100 to prepare mixed solvents. Match strength.
Subsequently, the bubbles are removed in a vacuum atmosphere for about 10 minutes so that the mixed solvent can be maximally contacted with the inner surface of the rough surface, and then the ultrafine scattering intensity is measured using a neutron ultrafine scattering apparatus.
6a shows the result of measuring the neutron ultrafine scattering by adding Cu 50 Zr 50 , which is an amorphous metal, to hydrogenated ethanol, and FIG. 6b shows the result of measuring neutron ultrafine scattering by adding Cu 50 Zr 50 to deuterated ethanol , And the result of measurement of neutron ultrafine scattering by adding Cu 50 Zr 50 to a solution obtained by mixing hydrogenated ethanol and deuterated ethanol as described above is shown in FIG. 6C. Here, circles filled with black correspond to hydrogenated ethanol, deuterated ethanol, and ethanol mixed solvent, respectively, and hollow circles correspond to Cu 50 Zr 50 . The x-axis (horizontal axis in the drawing) represents the scattering vector Q and the y-axis (vertical axis in the figure) represents the scattering intensity I (Q).
6A and 6B, neutron scattering intensity of amorphous metal is relatively high in hydrogenated ethanol (FIG. 6A) and relatively small in deuterated ethanol (FIG. 6B). This is due to the relatively large scattering length difference (SLD i - SLD j ) between the solvent and the amorphous metal in hydrogenated ethanol and the relatively small scattering length density difference in deuterated ethanol.
On the other hand, referring to FIG. 6C, it can be seen that the scattering intensity of the mixed solvent and the scattering intensity of the amorphous metal are almost the same. When the rough amorphous metal surface is immersed in such a specific mixed solvent, the rugged portion of the surface is filled with the mixed solvent to smooth the surface and the neutron scattering length density of the mixed solvent is equal to the scattering length density of the amorphous metal , It can be seen that no scattering occurs on the rough surface. FIG. 3C is an example of a graphical illustration, and FIG. 6C is an example of an experiment. In the examples, the concentration ratios of hydrogenated ethanol and deuterated ethanol in the mixed solvent were 20.8% and 79.2%, respectively, and the SLD of the mixed solvent was 4.74 x 10 10 cm -2 .
On the other hand, the density of the amorphous metal can be measured from the equation (2) showing the relationship between the density and SLD of a solution having a specific mixing ratio (neutron contrast matched solvent, CM).
&Quot; (2) "
In the equation, ρ denotes the density value of the amorphous metal material, i denotes the component of the amorphous metal material, n denotes the number of components contained in the amorphous metal material as natural numbers, SLD CM denotes the scattering intensity of the sample, Wherein A represents the scattering length density of the mixed solvent when the scattering intensity of the solvent is the same, N A represents the number of Avogadro, f i represents the fraction of component i contained in the amorphous metal material, and M i is included in the amorphous metal material B i represents the neutron scattering length of the component contained in the amorphous metal material.
The neutron scattering lengths (b i ) of copper (Cu) and zirconium (Zr), which are components included in the amorphous metal material, are shown in Table 2.
In the examples, the density of the amorphous metal from the mixed solvent to which the amorphous metal sample was added was measured to be 8.19 g / cm 3 . Which is about 13% higher than the document value of 7.25 g / cm 3 (References Z. Altounian, JO Strom-Olsen, Phys. Rev. B 27 (7) (1983) 4149 -4156). This error can be caused by errors in volume or weighing when mixing the mixed solvent, surface tension of the mixed solvent, accuracy of scattering length density, and the like.
However, when the method using the linear graph of FIG. 7 described above is used, the concentration ratio of the mixed solvent can be obtained more easily than the method of repeatedly controlling the concentration ratio, and a more accurate value can be obtained. This will be described in more detail in the second embodiment below.
If the mixing ratio of the mixed solvent is set more closely or the factors of the error in the process are reduced, the error range can be reduced.
However, if the neutron intensity is measured after reducing the error range, it can be predicted that this is due to the oxide film or pore formed on the surface of the amorphous metal. Also, if the neutron intensity is measured after removing the oxide film on the surface, it can be understood that this is due to non-uniformity such as precipitates or impurity particles in the amorphous metal, or due to pores.
Therefore, by using the method of measuring the uniformity and density from the rough surface of amorphous metal by using neutron ultrafine scattering, scattering that can occur on the rough surface of amorphous metal is removed, and uniformity of the material inside, existence of pores And approximate density can be estimated.
Example 2
The uniformity, the existence of pores and the density of the amorphous metal are estimated in the same manner as in Example 1, except that the mixing ratio of hydrogenated ethanol and deuterated ethanol is controlled in the mixed solvent.
The scattering intensity of the sample mixed with the amorphous metal in the mixed solvent measured in Example 1 is converted into invariant Q Inv (Q) (unit Å -3 cm -1 ) by the following equation ( 3 ). Here, Q Inv (Q) represents the area of the graph when I (Q) Q 2 and Q are expressed in a graph in Equation (3). Q min and Q max are the scattering vectors at the beginning and end of the scattering intensity measured.
&Quot; (3) "
On the other hand, according to Equation (4), the square root value of Q Inv (Q) is proportional to the difference between the scattering length density of the amorphous metal and the scattering length density of the mixed solvent.
&Quot; (4) "
Here, a graph is shown with the square root of Q Inv (Q) as the y axis and the volume ratio of deuterated ethanol as the x axis, and the square root of the Q Inv (Q) Change some of the values to negative values. In Example 2, the volume ratio of deuterated ethanol negatively x-axis-symmetrized is 78.2% and 100%.
A graph according to the above method is shown in Fig. Referring to FIG. 7, the point at which the square root value of Q Inv (Q) becomes zero is the mixing ratio of the mixed solvent in which the scattering length density of the sample coincides with the scattering length density of the mixed solvent.
From this, it can be seen that the mixture concentration ratio of hydrogenated ethanol and deuterated ethanol in the mixed solvent is 29.8% and 70.2%, respectively, and the scattering length density value of the mixed solvent at this time is 4.1841 x 10 10 cm -2 , The density of the metal is 7.23 g / cm 3 .
It can be seen that the density value can be measured more accurately than the first embodiment because it is a value belonging to the document value and an error range within about 1% to 2%. [(Density = 7.22 g / cm 3) References. Y. Li, Q. Guo, JA Kalb, CV Thompson, Science 322 (2008) 1816-1819, (Density = 7.25 g / cm 3 ) References Z. Altounian, JO Strom-Olsen, Phys. Rev. B 27 (7) (1983) 4149-4156, (Density = 7.39 g / cm 3 ) References Y. Calvayrac, JP Chevalier, M. Harmelin, A. Quivy, J. Bigot, Phil. Mag. 48 (4) (1983) 323-332). Also, it can be seen that the mixing ratio of hydrogenated ethanol and deuterated ethanol was measured more easily in the mixed solvent than in Example 1. [
However, in the case where the linear graph as shown in FIG. 7 is not formed, it can be predicted that it is due to the oxide film or the pores formed on the surface of the amorphous metal. Also, if a linear graph is not formed after removing the oxide film on the surface, it can be understood that this is due to non-uniformity such as precipitates or impurity particles in the amorphous metal, or due to pores.
In summary, utilizing the method of measuring the uniformity and density from the rough surface of amorphous metal by using neutron ultrafast scattering according to the embodiments, scattering that can occur on the rough surface of the amorphous metal can be removed, Uniformity of pores, existence of pores, and density values can be estimated. In addition, through further analysis, the specific surface area (surface area / volume) of the rough surface can be measured.
While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, Of the right.
10: preceding monochromator 20: BHA monochromator
30: Cell 40: BHA analyzer
50: detector
Claims (10)
Preparing a mixed solvent containing two or more liquids and measuring a scattering intensity of the mixed solvent using an ultra small angle neutron scattering instrument;
Measuring the scattering intensity of the sample using the neutron micro angle scattering apparatus after preparing the sample by inserting the amorphous metal material into the mixed solvent;
Adjusting a concentration ratio of the two or more liquids contained in the mixed solvent so that the scattering intensity of the mixed solvent and the scattering intensity of the sample have the same value;
Determining the uniformity of the amorphous metal material, when the scattering intensity of the mixed solvent is equal to the scattering intensity of the sample, and determining that the interior of the amorphous metal material is uniform; And
Obtaining a density of the amorphous metal material by using a scattering length density of the mixed solvent when the inside of the amorphous metal material is determined to be uniform;
Wherein the density of the amorphous metal is measured using neutron ultrafast scattering.
Preparing a mixed solvent containing two or more liquids and measuring a scattering intensity of the mixed solvent using an ultra small angle neutron scattering instrument;
Measuring the scattering intensity of the sample using the neutron micro angle scattering apparatus after preparing the sample by inserting the amorphous metal material into the mixed solvent;
Adjusting a concentration ratio of the two or more liquids contained in the mixed solvent so that the scattering intensity of the mixed solvent and the scattering intensity of the sample have the same value; And
Determining the uniformity of the amorphous metal material, when the scattering intensity of the mixed solvent is equal to the scattering intensity of the sample, and determining that the interior of the amorphous metal material is uniform;
To determine the uniformity of the amorphous metal using the neutron ultrafast scattering.
Wherein the mixed solvent is a mixture of a liquid containing hydrogen (H) and a liquid containing deuterium (D), and measuring the density of the amorphous metal using the neutron ultrafast scattering.
In the step of adjusting the concentration ratio of the two or more liquids,
Wherein the mixed solvent has a scattering length density value equal to a scattering length density value of the amorphous metal material, and the ratio of the concentration of the hydrogen-containing liquid to the concentration of the deuterium- A method for measuring the density of amorphous metal using scattering.
Wherein the mixed solvent is a mixture of hydrogenated ethanol (C 2 H 5 OH) and deuterated ethanol (C 2 D 5 OD), and measuring the density of the amorphous metal using the neutron ultrafast scattering.
Wherein the mixed solvent is a mixture of water (H 2 O) and heavy water (D 2 O), and the density of the amorphous metal is measured using the neutron ultrafine scattering.
Wherein the step of obtaining the density of the amorphous metal material comprises:
A method for measuring the density of an amorphous metal using neutron ultrafine scattering, which obtains a density value of the amorphous metal material from the following equation.
[Mathematical Expression]
In the equation, ρ denotes the density value of the amorphous metal material, i denotes a component of the amorphous metal material, n denotes the number of components contained in the amorphous metal material as a natural number, SLD CM denotes the scattering of the sample Where N A is the number of Avogadro, f i is the fraction of the component i contained in the amorphous metal material, M i is the fraction of the component i contained in the amorphous metal material, Represents the molecular weight of the component i included in the amorphous metal material, and b i represents the scattering length of the component included in the amorphous metal material.
Wherein the step of preparing the amorphous metal material comprises:
Method, using a very small angle neutron scattering for measuring the density of the amorphous metal further comprising the step of heat treatment at a glass transition temperature lower than the temperature (T g) of the amorphous metal material.
Wherein the step of preparing the amorphous metal material comprises:
Further comprising grinding the surface of the amorphous metal material to measure the density of the amorphous metal using neutron ultrafast scattering.
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