KR100321055B1 - METHOD FOR CHARGING ALLOY IRON DURING MANUFACTURING OF GLASS BEADS OF Fe-Mn or Fe-Cr ALLOY IRON, AND METHOD FOR MANUFACTURING THE GLASS BEADS - Google Patents

Abstract

PURPOSE: A method for charging Fe-Mn or Fe-Cr alloy iron is provided to manufacture glass beads of Fe-Mn or Fe-Cr alloy iron for analyzing fluorescence X-rays without damage of platinum container, and a method for manufacturing the glass beads of Fe-Mn or Fe-Cr alloy iron using the alloy iron charging method is provided. CONSTITUTION: The method for charging Fe-Mn or Fe-Cr alloy iron into a platinum container during manufacture of glass beads for analyzing constituents of Fe-Mn or Fe-Cr alloy iron using fluorescence X-rays is characterized in that the flux is again charged into the platinum container so that the alloy iron powder sample, oxidizer and flux charged into the lower part of the platinum container are covered by the flux after mixing and charging a Fe-Mn or Fe-Cr alloy iron powder sample and oxidizer having a lower melting point than the flux into the upper central part of the flux so that a mixture of the alloy iron powder sample and oxidizer does not directly contact with the platinum container after charging flux into a platinum container. The method for manufacturing glass beads of Fe-Mn or Fe-Cr alloy iron comprises a step of oxidizing alloy iron by reacting the alloy iron with the oxidizer at a temperature that is higher than the melting point of oxidizer, but lower than the melting point of flux as maintaining the state that a Fe-Mn or Fe-Cr alloy iron powder sample does not directly contact with a platinum container; a step of melting the alloy iron sample by increasing temperature of the oxidized alloy iron to a point higher than the melting point of the flux so that the oxidized alloy iron is reacted with the flux; and a step of forming glass beads by heating the melted alloy iron sample using high frequency, burner or ordinary manner used in manufacturing other glass beads, and cooling the formed glass beads.

Description

Method of loading ferroalloy and manufacturing glass beads in manufacturing glass beads of iron-manganese and iron-chromium alloys

The present invention is a Fe-Mn or Fe-Cr alloy in the platinum container in the manufacture of glass beads (glass bead) for the rapid analysis of the Fe-Mn, Fe-Cr alloy iron sample in the powder sample using fluorescent X-rays The present invention relates to a method for charging iron and a glass bead manufacturing method, and particularly to manufacture fluorescence X-ray analysis glass beads used to quantify elemental elements of Fe-Mn and Fe-Cr alloy iron, which are added as an auxiliary material in a steelmaking process in a steel mill. It is about a method.

In steel mills, ferroalloy is added to the molten metal for the purpose of adjusting the elements of the steel or deoxidizing or desulfurizing the steel during the steelmaking process. At this time, the amount of trace elements in steel can be calculated and the characteristics of the steel can be calculated only when the content of elemental elements of the ferroalloy is accurately known. Therefore, the rapid and accurate analysis of Fe-Mn and Fe-Cr alloy samples to produce high-quality steel It is one of the very important factors.

Conventional ferroalloy analysis method is a wet analysis method in which ferroalloy is dissolved in hydrochloric acid or nitric acid, and analyzed by gravimetric method, colorimetric method, or spectroscopic method depending on the element, and finely pulverized powdered ferroalloy, and then press-molded to make a disk state There is a method of analyzing it by fluorescent X-rays. Among these analysis methods, the wet analysis method is accurate, but the pretreatment process is different depending on the component elements, which requires a lot of analysis time, requires mastery of the operator, and difficult analysis process.

In addition, the fluorescence X-ray analysis method by the press molding method has the advantage that it is possible to quickly analyze several elements at the same time, but in the particle size effect and non-uniformity of the crystal structure and bonding state of the particles due to the irregularity of the particles of ferroalloy itself Due to the mineral effect, there is a disadvantage that the accuracy is lower than the wet analysis and there are many errors. Since creating a ferro-alloy to the glass beads can eliminate particle size effect and the effect on the mineral fluorescent X- ray analysis can dramatically improve the degree (精度) of the quantitative analysis, but usually the powder metal samples, such as iron alloy is Li ₂ B ₄ When using a flux such as O ₇ , the sample is not dissolved in the solvent, making glass beads impossible, and when a flux and an oxidant are used together, the glass beads are prepared using a platinum container unlike a general oxide sample. Due to the alloying of the sample and the platinum container, the platinum container was perforated or damaged, making glass beads impossible.

Accordingly, an object of the present invention is to provide a Fe-Mn, Fe-Cr alloy iron charging method that can produce glass beads of Fe-Mn, Fe-Cr alloy iron for fluorescence X-ray analysis without damaging the platinum container. .

Another object of the present invention is to provide a method for producing glass beads of Fe-Mn or Fe-Cr alloy using the Fe-alloy iron charging method of the present invention as described above.

1 is a flow chart schematically showing a specimen manufacturing process by a conventional press molding method,

Figure 2 is a schematic cross-sectional view showing a charging method of ferroalloy, oxidant and flux for producing glass beads according to the method of the present invention,

3 is a flowchart schematically showing an embodiment of the glass bead manufacturing method of the present invention;

Figure 4 is a graph showing the Cr concentration and X-ray intensity of the Fe-Cr standard sample prepared by the press molding method,

Figure 5 is a graph showing the Cr concentration and X-ray intensity of the Fe-Cr standard sample prepared according to the glass bead manufacturing method of the present invention,

6 is a graph showing Mn concentration and X-ray intensity of the Fe-Mn standard sample prepared by the press molding method,

7 is a graph showing Mn concentration and X-ray intensity of the Fe-Mn standard sample prepared according to the glass bead manufacturing method of the present invention.

Explanation of symbols on the main parts of the drawings

1,1 '... flux (primary flux) 3 ... platinum container

2 ... Fe-Mn or Fe-Cr alloy iron powder and oxidant mixture

According to the first aspect of the present invention,

After charging the flux into the platinum container, the Fe-Mn or Fe-Cr alloy iron powder sample and the oxidizing agent having a lower melting point than the flux were charged in the upper central portion of the flux so as not to be in direct contact with the platinum container. Analyzing the elements of the Fe-Mn or Fe-Cr alloy iron, including the oxidant and the flux charged in the platinum container so that the flux charged in the lower portion of the platinum container is covered, using fluorescent X-rays Provided is a method of charging Fe-Mn or Fe-Cr alloy iron in a platinum container in manufacturing glass beads.

According to the second aspect of the present invention,

While the Fe-Mn or Fe-Cr alloy powder samples were not in direct contact with the platinum container, the Fe-Mn or Fe-Cr alloy iron was reacted with the oxidizer at a temperature higher than the melting point of the oxidant but lower than the melting point of the flux. Oxidizing iron;

Heating to a temperature higher than the melting point of the flux to react the pre-oxidized Fe alloy with the flux to melt the alkali; And

Heating the molten Fe alloy sample by a conventional method used for high frequency, burner or other glass beads to form and cool glass beads; It is provided in a glass bead manufacturing method of Fe-Mn or Fe-Cr alloy iron containing.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

The present inventors can eliminate the particle size or mineral effect caused by the conventional press molding method in fluorescence X-ray analysis by making glass bead of iron alloy, which can drastically improve the accuracy of quantitative analysis. Experimental results show that powder metal samples such as ferroalloy do not melt well even when used with conventional fluxes such as Li ₂ B ₄ O _7, and even when the flux and oxidant are used together, After confirming that there are problems in glass bead production, such as perforation or damage, the study was continued. As a result, the sample, flux and oxidant were charged into the platinum container according to the melting temperature so that the sample and platinum container were not directly contacted and the temperature was increased. We found that glass beads can be produced by oxidizing and melting with precise control. After a phrase further continued and completed the present invention.

For comparison, the press molding method and glass bead method for forming X-ray analysis are compared.

In order to prepare the specimen by the press molding method and the glass bead method, the ferroalloy powder must first be crushed to below a certain particle size. In the case of glass beads, the particle size does not significantly affect the analysis because the alkali melting process is performed, but in the case of the press molding method, the particle size should be as small as possible and finely crushed. For this purpose, iron alloy powder, usually dried in an oven at 105 ° C. for 1 hour, is placed in a disk-type crusher and crushed for 10 minutes. The crushed iron powder is stored in a vacuum desiccator and used for pressure molding and glass bead preparation. do.

Figure 1 shows the manufacturing process of the ferroalloy disk by the general pressing method, in the case of Fe-Cr or Fe-Mn, first weighed boric acid (for example, about 6gr), and then put it in the press molding machine and flatten it with a slight pressure. After crushing, the crushed iron alloy powder (for example, 4 gr) is evenly charged on boric acid, and then pressurized to a pressure of about 2500 kg / cm 2 to produce a disc.

Meanwhile, when manufacturing glass beads from ferroalloy, it is important to prevent the platinum container from being damaged or perforated by alloying the metal component of the ferroalloy and the platinum of the platinum vessel at high temperature before the ferroalloy is oxidized. Direct contact with this platinum container should be avoided.

Therefore, in the method of charging Fe-Mn or Fe-Cr alloy iron into the platinum container in manufacturing glass beads according to the first aspect of the present invention, a high melting point flux is first charged into the platinum container to prevent alloying with the platinum container and the alloy iron. After that, charge and load Fe-Mn or Fe-Cr alloy iron sample and oxidizing agent in the upper middle part of the flux so as not to be in direct contact with the platinum container, and again to cover all of the ferrous alloy, the oxidizing agent and the flux below. The method of charging the flux into the platinum container is used.

By charging the sample, the oxidant and the flux into the platinum container, an oxidation reaction between the sample and the oxidant occurs without first contacting the sample and the platinum container at a low temperature as the temperature rises, and then with the sample oxidized at a high temperature. As the flux reacts and undergoes a two-step reaction in which a melting reaction occurs, the platinum container never comes into contact with the sample until the oxidation reaction of the sample is completed. No scattering is caused.

The flux (first flux) usable in the present invention may be any kind having a melting point of 900 ° C. or more as the flux for alkali melting, for example lithium tetraborate (Li ₂ B ₄ O ₇ ), lithium metaphosphate ( LiPO ₃ ), a mixture of lithium tetraborate and lanthanum oxide (Li ₂ B ₄ O ₇ + La ₂ O ₃ ), a mixture of lithium metaphosphate and boron oxide and lithium tetraborate (LiPO ₃ + B ₂ O ₃ + Li ₂ B ₄ O ₇ ), preferably lithium tetraborate (Li ₂ B ₄ O ₇ ). These solvents are excellent in miscibility with the ferroalloy sample, so that the alloy sample dissolves and mixes well, and is stable in the formation of glass beads since the glass beads are not cracked by cooling.

The amount of the first flux is preferably used 50-60 times based on the weight of the ferroalloy sample. If the amount of flux is less than 50 times the weight of the sample, the amount of solvent is too small so that the beads crack during cooling after glass bead formation, and if the amount of solvent becomes more than 60 times the weight of the sample, the relative amount of flux increases and the amount of sample This decreases the sensitivity of the glass beads to be prepared and then analyzed.

As a oxidizing agent for oxidizing ferroalloy before the reaction with the flux, a mixture of Na ₂ CO ₃ and Na ₂ O ₂ in a 2: 1 ratio was found to be preferable. 20-25 times by weight is preferable.

When using an oxidizing agent in which Na ₂ CO ₃ and Na ₂ O ₂ are mixed in a 2: 1 weight ratio, cracking of the glass beads due to shrinkage during cooling during the glass bead manufacturing process is minimized. When the oxidant is used at less than 20 times the sample weight, all of the ferroalloy samples are not oxidized, some remain as metals, and the crucibles are damaged because the remaining metals react with the platinum crucible and alloy. In addition, even when the oxidizing agent is used at 25 times or more of the sample weight, the iron oxide is sufficiently oxidized, so no further effect improvement is expected. Therefore, the oxidizing agent may be used at 20 to 25 times the sample weight.

The oxidant may be mixed with a Fe-alloy sample in advance and then charged into a platinum container, and the oxidant and the ferroalloy sample are separately charged into a platinum container so as not to be in direct contact with the platinum container according to the charging method of the present invention. You may mix these.

When the mixing ratio of the flux and the oxidant to the weight of the ferroalloy sample is lower than the mixing ratio, complete oxidation reaction of the ferroalloy cannot be expected and alloying with the platinum dish occurs or the ferroalloy sample is not completely melted. On the other hand, when the mixing ratio of the flux and the oxidant to the weight of the ferroalloy sample exceeds the mixing ratio, a large amount of bubbles are generated or difficulty in obtaining accurate X-ray strength of the ferroalloy.

As described above, the ferroalloy sample charged into the platinum vessel is subjected to oxidation and alkali melting in an electric furnace capable of temperature programming, and then the platinum vessel is manufactured into glass beads through a normal heating step using a high frequency or burner.

The oxidation and melting reaction is sequentially in accordance with the method of the present invention by heating the sample in an electric furnace from 650 ° C to 750 ° C over 1 hour, and then raising the temperature in two steps over 1 hour from 750 ° C to 1000 ° C. Is performed.

In other words, when the sample is heated from 650 ° C to 750 ° C over 1 hour, the mixed oxidizing agent of Na ₂ CO ₃ and Na ₂ O ₂ having low melting point is melted first to undergo oxidation reaction with Fe-Mn or Fe-Cr alloy iron. In this case, it acts to prevent contact between the ferroalloy and the platinum dish while the surrounding ferroalloy is oxidized. After complete melt oxidation, the temperature was raised again to 1000 ° C. over 1 hour to allow Li ₂ B ₄ O ₇ around the oxidant to melt. At this time, it is good to shake occasionally so that the oxidant which is already molten is mixed with Li ₂ B ₄ O ₇ well.

That is, Fe-Mn and Fe-Cr alloy samples must be completely oxidized first and then mixed with the flux. Therefore, proper temperature and time should be maintained during oxidation and melting. Oxidation and melting at a temperature lower than the oxidation temperature does not completely produce an oxidation reaction between the oxidizing agent and the ferroalloy sample, and glass beads cannot be produced. On the contrary, when the temperature is too high, a mixture reaction between the oxidation reaction and the flux occurs. Glass bead manufacturing becomes impossible. In addition, if the temperature and time conditions are out, there is a problem that the glass bead is cracked and cannot be used in the cooling process after the glass bead is formed or the sample and the solvent in the glass bead are not uniformly mixed.

On the other hand, excessive use of flux and oxidant may cause excessive bubbles to form glass beads or poor glass beads, and long-term storage may be difficult due to its hygroscopicity. Therefore, the total amount of the sample, flux and oxidant is suppressed to 9 gr or less. Good to do.

In addition, when bubbles are generated, a small amount of LiI may be added to suppress bubbles. When the oxidation and melting operations are completed, glass beads may be manufactured by fluorescence of glass beads according to conventional means using a high frequency or burner for producing glass beads. It is measured by an X-ray analyzer.

EMBODIMENT OF THE INVENTION Hereinafter, the Example of this invention is described.

Example 1 Preparation of Glass Beads

Accurately weighed Li ₂ B ₄ O ₇ 5gr into a platinum dish and then leveled the surface. Thereafter, the surface center of Li ₂ B ₄ O _{7 in} the platinum dish was slightly recessed, and ₂ gr of a mixture of Na ₂ CO ₃ and Na ₂ O ₂ in a 2: l mixture was charged in the recess. 0.1gr of Fe-Mn or Fe-Cr alloy alloy samples were mixed and charged on the oxidant mixture as shown in FIG. 2, and then again covered with the entire upper layer with Li ₂ B ₄ O ₇ 1gr.

The loaded platinum dish was placed in a temperature-programmable electric furnace and heated up at 650 ° C. to 750 ° C. for 1 hour to oxidize the powder to be alloyed with the oxidizing agent. The temperature was raised to allow the Li ₂ B ₄ O ₇ surrounding the oxidant to melt.

When melting the mixed oxidizing agent, be careful not to boil in the platinum dish, and occasionally shake to mix them well with Li ₂ B ₄ O ₇ . No damage to the platinum plate was found during oxidation and melting. After oxidation and melting were completed, the glass beads were prepared by molding into a preheated platinum mold.

3 schematically illustrates the glass bead manufacturing process.

Example 2 Fluorescence X-Ray Analysis

Fe-Cr standard sample discs prepared by a conventional press molding method and Fe-Cr discs prepared according to the method described in Example 1 were measured by a fluorescence X-ray analyzer, and the measured Cr calibration curve results are shown in FIG. 4 and FIG. 5 is shown respectively.

Points created by the conventional method in Figure 4 is not well proportional to the fluorescent X-ray intensity in the 45-75% range because the intensity of the fluorescent X-ray is affected by the particle size and mineral effect described above . On the other hand, the results measured by glass beads according to the present invention shows that the proportional relationship between Cr concentration in the Fe-Cr alloy iron and the fluorescence X-ray intensity is well established in the range of 45-75%. 6 is a calibration curve graph of Mn measured using a Fe-Mn standard sample disk manufactured by a conventional press molding method, and FIG. 7 is a calibration curve of Mn measured using a disk manufactured by the glass bead method of the present invention.

Points created by the conventional method in FIG. 6 are not well proportional to the fluorescence X-ray intensity in the range of 75-85%, while the results measured by glass beads in FIG. 7 indicate Mn concentration in Fe-Mn alloy iron. It is shown that the proportional relationship between and fluorescence X-ray intensity is well established in the same range. Therefore, when the ferroalloy is made of glass beads, the accuracy of the quantitative analysis results is much higher than that of the conventional press molding method.

As described above, the Fe-Mn or Fe-Cr alloy iron glass bead manufacturing method of the present invention is a specimen preparation method for analyzing the ferroalloy quickly and accurately, compared to the conventional wet method, the analysis time is significantly reduced and the operator's skill High accuracy can be guaranteed regardless of particle size and mineral effect of ferroalloy in fluorescence X-ray analysis. In addition, according to the present invention, the main element and the trace element in the ferroalloy can be measured simultaneously, and the analysis accuracy is greatly improved for each element.

Claims (9)

After charging the flux into the platinum container, after mixing and charging a Fe-Mn or Fe-Cr alloy iron powder sample and an oxidizing agent having a lower melting point than the flux, the ferrous powder was not mixed with the platinum container. The element of Fe-Mn or Fe-Cr alloy iron is charged using a fluorescent X-ray, characterized in that the flux is charged into the platinum container again so that the sample and the oxidant and the flux charged in the lower part of the platinum container are covered. Method of charging Fe-Mn or Fe-Cr alloy iron in platinum container in manufacturing glass beads for analysis The method of claim 1, wherein the flux is lithium tetraborate (Li ₂ B ₄ O ₇ ), lithium metaphosphate (LiPO ₃ ), a mixture of lithium tetraborate and lanthanum oxide (Li ₂ B ₄ O ₇ + La ₂ O ₃ ) , A mixture of lithium metaphosphate and boron oxide and lithium tetraborate (LiPO ₃ + B ₂ O ₃ + Li ₂ B ₄ O ₇ ), The method of claim 2, wherein the flux is lithium tetraborate (Li ₂ B ₄ O ₇ ) The method according to any one of claims 1 to 3, wherein the flux is charged in an amount of 50-60 times based on the weight of the ferroalloy sample. The method of claim 1, wherein the oxidizing agent is a mixture of Na ₂ CO ₃ and Na ₂ O ₂ in a weight fertilizer 2: 1, and the amount of the oxidizing agent is 20 to 25 times based on the weight of the ferroalloy sample. 4. A method according to any one of claims 1 to 3, wherein the total amount of ferroalloy, oxidant and flux does not exceed 9 gr. Oxidizing the ferroalloy by reacting the ferroalloy with an oxidant at a temperature higher than the melting point of the oxidant but lower than the melting point of the flux while maintaining the Fe-Mn or Fe-Cr alloy powder sample in direct contact with the platinum container; Heating to a temperature higher than the melting point of the flux to react the oxidized iron with the flux to melt the ferroalloy sample; And Heating the molten ferroalloy sample in a conventional manner used for high frequency, burner or other glass bead formation to form and cool glass beads; Method for producing glass beads of Fe-Mn or Fe-Cr alloy iron containing The method of claim 7, wherein the pre-oxidation and melting step is carried out by oxidizing the sample in the electric furnace by heating the first temperature from 650 ° C to 750 ° C over 1 hour and heating up to 1000 ° C over 1 hour. How to The method of claim 7, wherein the flux is lithium tetraborate (Li ₂ B ₄ O ₇ ), lithium metaphosphate (LiPO ₃ ), a mixture of lithium tetraborate and lanthanum oxide (Li ₂ B ₄ O ₇ + La ₂ O ₃ ), a mixture of lithium metaphosphate and a mixture of boron oxide and lithium tetraborate (LiPO ₃ + B ₂ O ₃ + Li ₂ B ₄ O ₇ ), The oxidizing agent is a method characterized in that the mixture of Na ₂ CO ₃ and Na ₂ O ₂ in a weight ratio of 2: 1