A method for evaluating cleanliness of zirconium-based amorphous alloy

Abstract

The application provides a method for evaluating the cleanliness of a zirconium-based amorphous alloy, and relates to metal material smelting and casting, and comprises the following steps: determining the oxygen content in the zirconium-based amorphous alloy by using an inert gas fusion infrared analysis method to obtain the content of oxygen in different forms in the zirconium-based amorphous alloy; wherein the inert gas fusion infrared analysis method adopts a stepwise heating mode; and then calculating the cleanliness index of the zirconium-based amorphous alloy according to the content of the oxygen in different forms. The determination is performed by using the inert gas fusion infrared analysis method, without the need of complicated sample preparation and long-period verification, and the operation is simple and fast; and the stepwise heating mode is adopted to release the oxygen in different forms in the zirconium-based amorphous alloy in sections, so that a completely separated multi-peak oxygen release spectrum is obtained, the specific existing form and the corresponding content of the oxygen are analyzed according to the obtained oxygen release spectrum, and the cleanliness index is calculated according to the content of the oxygen in different forms in the alloy.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of metal material melting and casting, and particularly relates to a method for evaluating the cleanliness of a zirconium-based amorphous alloy. BACKGROUND

[0002] It is known that, compared with traditional metal materials, amorphous alloys have unique advantages such as high strength, high elasticity, excellent corrosion resistance and good forming ability, and have been widely used in many fields such as electronics, machinery and medical devices.

[0003] However, due to the increasing oxygen content of industrial raw materials and uncontrollable oxygen increase in the production process, the forming ability and mechanical properties of amorphous alloys are sharply reduced. Therefore, when amorphous master alloys are melted under industrial conditions, rare earth element Y is usually added as a deoxidizer to reduce the oxygen content of the alloy. Y element is added to the alloy in a certain proportion as a deoxidizer, which plays a role in avoiding the increase of oxygen in the alloy and compensating for the decrease of amorphous forming ability due to high oxygen content. However, due to the oxygen absorption effect, a large amount of Y2O3 inclusions are formed and enriched into the slag into the master alloy, which seriously affects the cleanliness of the master alloy. The amorphous alloy product containing Y2O3 inclusions may have defects such as pores or local crystallization inside, which has a great negative effect on the mechanical properties and corrosion resistance of the product. Therefore, it is necessary to quickly evaluate the cleanliness of zirconium-based amorphous master alloys and amorphous alloy products in industrial production.

[0004] At present, the total oxygen content analysis method of the alloy and the method for verifying the maximum amorphous critical size (Dmax) are usually used to evaluate the cleanliness of the zirconium-based amorphous alloy. Among them, the total oxygen content analysis method of the alloy is a conventional inert gas fusion-infrared absorption analysis method. This method uses a rapid temperature program, and various forms of oxygen in the sample are completely released in a short time (about 30s). The oxygen release curve is formed by the superposition of oxygen release peaks in different states to form a single peak, which reflects the total oxygen content of the measured sample. However, this method has a large error. The method for verifying the maximum amorphous critical size has high accuracy, but it needs to use an arc furnace to melt, vacuum cast and cast the master alloy into a round bar sample, and then use XRD or DSC to verify whether the alloy sample of different sizes is amorphous. The sample preparation process is complex and time-consuming, and the verification period is long. SUMMARY

[0005] Therefore, the present application provides a method for evaluating the cleanliness of a zirconium-based amorphous alloy, which mainly aims to provide a simple and fast method for evaluating the cleanliness of a zirconium-based amorphous alloy with less error.

[0006] In order to solve the above problems, the present application provides a method for evaluating the cleanliness of a zirconium-based amorphous alloy, comprising the following steps:

[0007] Step 1): The oxygen content in the zirconium-based amorphous alloy was determined by inert gas melting infrared analysis to obtain the content of oxygen in different forms in the zirconium-based amorphous alloy;

[0008] The inert gas melting infrared analysis method employs a stepped heating method.

[0009] Step 2): Calculate the cleanliness index of the zirconium-based amorphous alloy based on the oxygen content in the different forms of existence.

[0010] Furthermore, in step 1), the stepped heating includes:

[0011] First heating stage: Heat to the first set temperature and maintain the temperature for the first set time;

[0012] Second heating stage: Heat to the second set temperature and maintain the temperature for the second set time.

[0013] Furthermore, the first set temperature and the second set temperature are controlled by adjusting the heating power;

[0014] The heating power of the first heating stage is 2500-3000W; the first set temperature is 1400-1600℃; and the first set time is 60-80s. The heating power of the second heating stage is 5000-6000W; the second set temperature is 2100-2300℃; and the second set time is 40-60s.

[0015] Furthermore, the different forms of oxygen include matrix oxygen and oxygen in oxides;

[0016] Of which, the matrix oxygen content, expressed as a mass percentage, is w. O The oxygen content w in oxides Oy .

[0017] Furthermore, the formula for calculating the cleanliness index of the zirconium-based amorphous alloy is as follows: I = w Oy / w Ot ;

[0018] Among them, w Oy w represents the oxygen content in the oxide. Ot The content of matrix oxygen w O The oxygen content w in oxides Oy sum.

[0019] Furthermore, in step 1), the zirconium-based amorphous alloy is a granular zirconium-based amorphous alloy.

[0020] Further, the diameter of the granular zirconium-based amorphous alloy is 3-5 mm; and the weight of the granular zirconium-based amorphous alloy is 0.05-0.15 g.

[0021] Further, the granular zirconium-based amorphous alloy is obtained by sampling the upper, middle and lower parts of the zirconium-based amorphous alloy ingot or the zirconium-based amorphous alloy piece and then cutting and polishing.

[0022] Further, in the step 1), the zirconium-based amorphous alloy is a zirconium-based amorphous alloy containing rare earth elements; preferably, the rare earth elements are Y.

[0023] Further, in the step 1), the inert gas fusion infrared analysis method uses an oxygen-nitrogen-hydrogen analyzer; the analysis crucible used in the inert gas fusion infrared analysis method is a graphite sleeve crucible; and the dissolving agent used in the inert gas fusion infrared analysis method is a nickel basket.

[0024] The method for evaluating the cleanliness of a zirconium-based amorphous alloy provided by the application has the following beneficial effects:

[0025] 1. The method for evaluating the cleanliness of a zirconium-based amorphous alloy provided by the application comprises the following steps: determining the oxygen content in the zirconium-based amorphous alloy by using an inert gas fusion infrared analysis method to obtain the content of oxygen in different forms in the zirconium-based amorphous alloy; wherein the inert gas fusion infrared analysis method uses a stepwise heating method; and then calculating the cleanliness index of the zirconium-based amorphous alloy according to the content of oxygen in different forms. It should be noted that the determination by using the inert gas fusion infrared analysis method does not need complicated sample preparation and long-period verification, and is simple and fast to operate; and the stepwise heating method makes the oxygen in different forms in the zirconium-based amorphous alloy release in sections to obtain a completely separated multi-peak oxygen release spectrum, the specific existence form and corresponding content of oxygen are analyzed according to the obtained oxygen release spectrum, and thus the cleanliness index is calculated according to the content of oxygen in different forms in the alloy.

[0026] 2. Further, the stepwise heating comprises: a first heating stage: heating to a first set temperature and keeping the temperature for a first set time to preliminarily melt the zirconium-based amorphous alloy and release part of the oxygen in different forms (i.e. matrix oxygen); a second heating stage: heating to a second set temperature and keeping the temperature for a second set time to completely melt the zirconium-based amorphous alloy and release residual oxygen.

[0027] 3. Furthermore, during the measurement, the alloy is processed into granular zirconium-based amorphous alloys. Granular samples have a larger specific surface area (surface area / volume), allowing for more thorough contact with the heating source during melting. This results in a faster rate of oxygen conversion into gas within the sample, preventing incomplete oxygen release due to incomplete melting and thus avoiding measurement errors. However, if the sample diameter and weight are too small, it may be rapidly vaporized, leading to an excessively fast oxygen escape rate that cannot be accurately captured by the infrared detector. Attached Figure Description

[0028] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. The drawings described below are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0029] Figure 1 (a) and 1(b) are the microscopic distribution diagrams of Y2O3 and the precipitation site distribution diagrams of the crystal phase in zirconium-based amorphous alloys containing Y element;

[0030] Figure 2 (a) and 2(b) are comparison diagrams of the oxygen release forms in the zirconium-based amorphous alloys obtained in Comparative Example 1 and Example 1 of the present invention, respectively.

[0031] Figures 3(a) and 3(b) show the XRD peak shapes of the zirconium-based amorphous alloy sample and the crystalline sample, respectively.

[0032] Figure 4 shows the cleanliness index of zirconium-based amorphous alloys. I The graph shows the relationship between the total oxygen content of the alloy and the alloy's forming ability. Detailed Implementation

[0033] To further illustrate the technical means and effects adopted by the present invention to achieve the intended purpose, the specific embodiments, structures, features, and effects according to the present invention will be described in detail below with reference to the accompanying drawings and preferred embodiments. In the following description, different "an embodiment" or "an embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0034] The total oxygen content of zirconium-based amorphous alloys containing Y element consists of two parts: matrix oxygen (O) in the alloy matrix and oxygen in the slag. Matrix oxygen exists in an atomic state and is one of the constituent elements of the alloy, while oxygen in the slag is generated during the smelting process of the amorphous alloy master alloy and is Y₂O₃. The production process of amorphous alloy products requires a rapid cooling process to prevent the precipitation of crystalline phases in the alloy. However, during rapid cooling, due to the relatively large size of Y₂O₃ inclusions, such as…Figure 1 (a) as shown, non-uniform nucleation will occur around Y2O3, leading to the precipitation of crystals around the inclusions, as shown in Figure 1 (b) as shown, further leading to the decrease of the amorphous forming ability of the master alloy, the deterioration of the mechanical properties, and the low yield of the amorphous product.

[0035] Therefore, the present application firstly sets up a two-step ladder heating program based on the different oxygen release temperatures, realizes the simultaneous analysis of the matrix oxygen (O) in the (Y-containing) zirconium-based amorphous master alloy and product and the oxygen (Y2O3) in the slag based on the metallurgical thermodynamics theory of isothermal carbothermal reduction reaction on the basis of the traditional inert gas melting infrared absorption method; secondly, the evaluation method of the cleanliness of the zirconium-based amorphous alloy and product is established by using the two indexes of the total oxygen content w(Ot) of the alloy and the oxygen content w(Oy) in the slag. The specific scheme is as follows:

[0036] The present application provides a method for evaluating the cleanliness of a zirconium-based amorphous alloy, comprising the following steps:

[0037] Step 1): the zirconium-based amorphous alloy sample containing Y element and a complexing agent are placed in a graphite sleeve crucible, and then an oxygen-nitrogen-hydrogen analyzer is used for inert gas melting infrared analysis, so that the zirconium-based amorphous alloy sample containing Y element is heated to a first set temperature and kept for a first set time, so that the sample is preliminarily melted and releases part of the oxygen in the existing form (matrix oxygen), then heated to a second set temperature and kept for a second set time to completely melt the sample and release the residual oxygen, and a completely separated double-peak oxygen release spectrum is obtained, so that the content of the matrix oxygen is w O , and the content of the oxygen in the oxide (the oxygen in the slag) is w Oy ;

[0038] The first set temperature and the second set temperature are controlled by adjusting the heating power; the heating power in the first heating stage is 2500-3000w, and the first set temperature is 1400-1600℃; the first set time is 60-80s; the heating power in the second heating stage is 5000-6000w, and the second set temperature is 2100-2300℃; the second set time is 40-60s; and the complexing agent is a nickel basket. Preferably, 0.1g of the sample (granular zirconium-based amorphous alloy) is weighed and cleaned, and then wrapped with about 1g of the nickel basket.

[0039] Step 2): the cleanliness index of the zirconium-based amorphous alloy is calculated according to the oxygen content in different existing forms, and the corresponding calculation formula is: the cleanliness index of the zirconium-based amorphous alloy I = w Oy / w Ot ; wherein w Ot is the content of the matrix oxygen w O and the content of the oxygen in the oxide w OyThe sum of the above.

[0040] It should be noted that the inert gas fusion infrared analysis method is used for determination, without complex sample preparation and long period of verification, simple operation and fast; and the stepwise heating mode is adopted, so that the different existing forms of oxygen in the zirconium-based amorphous alloy are released in sections, and a completely separated multi-peak oxygen release spectrum is obtained, the specific existing form of oxygen and the corresponding content are analyzed according to the obtained oxygen release spectrum, so as to calculate the cleanliness index according to the oxygen content in different existing forms in the alloy. It is more excellent in distinguishing the existing form of different types of oxygen in the alloy, and is suitable for analyzing the form and content of oxide impurities in zirconium-based amorphous master alloy and products.

[0041] In the first heating stage, the release temperature of the matrix oxygen is 1400-1600 DEG C under the heating power of 2500-3000w; and the matrix oxygen in the sample is released completely under the heating power and temperature in the first heating stage, and the oxygen in the oxide Y2O3 is not released. In the second heating stage, the release temperature of the oxygen in the oxide Y2O3 is 2100-2300 DEG C under the heating power of 5000-6000w; and the release temperature of the oxygen in the oxide Y2O3 is ensured under the heating power and temperature in the second heating stage.

[0042] The method of the present application is especially simple and has strong practicability, and can efficiently and accurately evaluate the technical problem of the cleanliness of Y-containing zirconium-based amorphous alloy and product in industry. On the one hand, compared with the existing evaluation method which evaluates the cleanliness of the alloy by verifying the maximum amorphous critical size (Dmax), the master alloy grade evaluation time can be reduced by 70% after using the present application, and the effect of reducing production cost can be realized. On the other hand, compared with the existing evaluation method which only uses a single total oxygen content w Ot (w(Ot)) to evaluate the cleanliness of the alloy, the evaluation accuracy can be improved from 80% to 97% after using the present application, and the goal of improving product yield can be realized.

[0043] After the cleanliness of the master alloy is evaluated by the method of the present application, the amorphous master alloy ingot or product with low cleanliness can be remelted and purified by adding Y element to reduce oxygen and slag removal to improve the purity of the alloy, realize the recycling of the alloy, and realize the goal of reducing production cost and improving product yield.

[0044] In some embodiments, before step 1), further comprising: sampling the upper, middle and lower positions of the zirconium-based amorphous alloy master alloy ingot or product (zirconium-based amorphous alloy piece) respectively, and then obtaining granular zirconium-based amorphous alloy by cutting and polishing. Preferably, the diameter of the granular zirconium-based amorphous alloy is 3-5 mm; the weight of the granular zirconium-based amorphous alloy is 0.1 g. By sampling at different positions respectively, more accurate data can be ensured.

[0045] The specific surface area (surface area / volume) of the granular sample is larger, which can make the sample contact with the heating source more fully when the sample is melted, and the internal oxygen element is converted into gas at a faster rate, avoiding incomplete melting of the sample inside, incomplete release of oxygen, and resulting in errors in the measurement results. However, if the diameter and weight of the sample are too small, the sample can be rapidly gasified, resulting in too fast oxygen escape rate, which cannot be accurately captured by the infrared detector.

[0046] It should be noted that different types of oxides include Fe2O3, MnO2, NiO, CuO, SiO2, Al2O3, and rare earth oxides Y2O3, La2O3, and CeO2, etc., which have different decomposition temperatures (oxygen release temperatures), and the order of their decomposition temperatures is: CuO < Fe2O3 < NiO < MnO2 < SiO2 < Al2O3 < Y2O3. According to the changes of the atmosphere and pressure conditions in the crucible during the analysis process of the inert gas fusion-infrared analysis method, the starting release temperature of the oxygen in the matrix oxygen (O) and the oxides (Y2O3, La2O3, CeO2, etc.) in the zirconium-based amorphous alloy containing rare earth elements under the condition is theoretically calculated. The carbon thermal reduction reaction equation of the oxide in the equilibrium state and the Gibbs free energy calculation formula are as follows:

[0047] ZxOy(s) + yC(g) = xZ + yCO(g)

[0048] △G = △G Ɵ + RT ln K

[0049] K = ( a z x p Co y ) / ( a c y a ZxOy )

[0050] In the formula: K is the equilibrium constant, a c y ,a z x , a ZxOy These represent the activities of carbon, oxides, and reduction products, respectively. p Co The partial pressure of Co. This is calculated... △G = 0 T The value is used to determine the starting temperature of the reaction, that is, the temperature at which oxygen begins to be released from the matrix oxygen and oxides. The calculation results are: the starting temperature for the release of oxygen from the matrix oxygen in the Y-containing zirconium-based amorphous alloy is 1500℃, and the release temperature for oxygen in the oxides is 2200℃.

[0051] Due to the extremely high reactivity of rare earth elements, their ability to bind with oxygen is far greater than that of elements such as Al, Ni, and Cu. This results in a limited variety of oxides in rare earth zirconium-based amorphous alloys, primarily consisting of rare earth yttrium oxides and a small amount of matrix oxygen. Therefore, a simple two-stage heating method can completely distinguish between the two forms of oxygen. Compared to other alloys with a wider range of oxide types, the two-stage heating method is more suitable for rare earth zirconium-based amorphous alloy systems, achieving the technical effect of avoiding interference from other types of oxides and thus obtaining more accurate oxygen content analysis results.

[0052] In addition, due to the high stability of rare earth oxides, the release of oxygen from rare earth oxides during the oxygen content detection process requires high temperature conditions. The temperature difference between the release of matrix oxygen and oxygen in oxides is about 700℃. Therefore, when designing the heating program, the heating power of the two heating processes differs significantly. This temperature difference ensures that under the first set temperature condition, the release of matrix oxygen begins while the release of oxygen in oxides has not yet begun, and under the second set temperature condition, the release of matrix oxygen is complete while the release of oxygen in oxides has just begun, thereby achieving the goal of completely separating and measuring oxygen in the two existing forms.

[0053] The present invention will be further described below with reference to specific embodiments and comparative examples.

[0054] In the examples and comparative examples, the cleanliness levels of six different batches of zirconium-containing amorphous master alloys were primarily determined. The specific alloy system was Zr-Cu-Ni-Al-Ti-Y. Due to differences in raw materials, impurity content, oxygen content, and operator techniques between batches, the amorphous forming ability of the four amorphous alloy preparation materials varied. Therefore, the six different batches were named master alloy samples 1-6. Master alloys with the same number in the examples and comparative examples belonged to the same batch.

[0055] Example 1

[0056] This embodiment provides a method for evaluating the cleanliness of zirconium-based amorphous alloys, specifically including the following steps:

[0057] Step 1): sample is taken from the upper and lower positions of the 1-6 master alloy sample respectively, and then processed into a smooth-surfaced granular sample to be tested, with a sample weight of about 0.1 g, ultrasonic cleaning with alcohol for 3 minutes, and drying on filter paper for standby;

[0058] Then, the Y-containing zirconium-based amorphous alloy sample and the cosolvent nickel basket are placed in a graphite sleeve crucible, and an oxygen-nitrogen-hydrogen analyzer is used for inert gas fusion infrared analysis, so that the Y-containing zirconium-based amorphous alloy sample is heated to a first set temperature and kept for a first set time, and then heated to a second set temperature and kept for a second set time, to obtain a completely separated double-peak oxygen release spectrum, as shown in Figure 2 (b); in the spectrum, the content of matrix oxygen w O and the content of oxygen in the oxide (oxygen in the slag) w Oy are obtained.

[0059] The first set temperature and the second set temperature are controlled by adjusting the heating power; the heating power in the first heating stage is 2750w, the first set temperature is 1500℃, the first set time is 70s, the heating power in the second heating stage is 5500w, the second set temperature is 2200℃, and the second set time is 50s.

[0060] Step 2): the cleanliness index of the zirconium-based amorphous alloy is calculated according to the content of matrix oxygen w O and the content of oxygen in the oxide (oxygen in the slag) w Oy , and the corresponding calculation formula is: the cleanliness index of the zirconium-based amorphous alloy I = w Oy / w Ot ; wherein w Ot is the sum of the content of matrix oxygen w O and the content of oxygen in the oxide w Oy .

[0061] The oxygen content and grade evaluation results obtained in this example are shown in Table 1.

[0062] Table 1 Oxygen content and grade evaluation results of 1-6 master alloy

[0063]

[0064] The grading standard for Y-containing zirconium-based amorphous master alloy is: when the total oxygen content w Ot of the alloy is less than 400ppm, the alloy is rated as class A; when the total oxygen content w Ot of the alloy is greater than 800ppm, the alloy is rated as class D; when the total oxygen content of the alloy is between 400ppm and 800ppm, the cleanliness index based on the method of the present application is usedI The master alloys are graded, and when I ≤0.5, the alloy is rated as B class, and when I >0.5, the alloy is rated as C class. Thus, the 1-6 master alloys are rated as follows: the No. 1 master alloy is rated as A class, the No. 2-3 master alloys are rated as B class, the No. 4-5 master alloys are rated as C class, and the No. 6 master alloy is rated as D class.

[0065] Comparative Example 1

[0066] The present comparative example provides a method for evaluating the cleanliness of a zirconium-based amorphous alloy, which specifically comprises the following steps:

[0067] Step 1): Sample is taken from the upper and lower parts of the No. 1-6 master alloy samples respectively, and the sample is processed into a smooth-surfaced granular test sample after sampling, with a sample weight of about 0.1 g. The sample is ultrasonically cleaned with alcohol for 3 minutes and dried on filter paper for standby;

[0068] Then, the above Y-containing zirconium-based amorphous alloy sample and a nickel basket containing a dissolving agent are placed in a graphite sleeve crucible, and an oxygen-nitrogen-hydrogen analyzer is used for inert gas fusion infrared analysis, so that the Y-containing zirconium-based amorphous alloy sample is directly heated to a set temperature and kept at the set temperature for a set time, to obtain a single-peak oxygen release spectrum, as shown in Figure 2 (a); in the spectrum, the content of matrix oxygen w O and the content of oxygen in the oxide (oxygen in the slag) w Oy are obtained.

[0069] The set temperature is controlled by adjusting the heating power; the heating power corresponding to the above set temperature is 5500 W; and the set time is 45 s.

[0070] Step 2): The cleanliness grade of the alloy is evaluated according to the total oxygen content in the master alloy sample, and the results are shown in Table 2.

[0071] Table 2 Total oxygen content and grade evaluation results of No. 1-6 master alloys

[0072]

[0073] The rating standard for the cleanliness grade of the alloy by the total oxygen content method is as follows: when the total oxygen content w Ot of the alloy ≤400 ppm, the alloy is rated as A class; when 400 ppm < w Ot of the alloy ≤600 ppm, the alloy is rated as B class; when 600 ppm < w Ot of the alloy ≤800 ppm, the alloy is rated as C class; and when w OtWhen the content of the alloy is more than 800 ppm, the alloy is rated as D. Therefore, the rating types of the 1-6 master alloys are as follows: the 1 master alloy is rated as A, the 2 and 5 master alloys are rated as B, the 3 and 4 master alloys are rated as C, and the 6 master alloy is rated as D.

[0074] Comparative Example 2

[0075] The present comparative example provides a method for evaluating the cleanliness of a zirconium-based amorphous alloy, specifically comprising the following steps:

[0076] Step 1): Sample is taken from the upper and lower parts of the 1-6 master alloy samples respectively, with a weight of 80-100 g, and is cleaned with alcohol for 3 minutes and dried on filter paper for standby;

[0077] Step 2): The alloy sample is prepared into a rod-shaped sample with a diameter of Φ14 mm by vacuum casting, and the equipment used is an arc melting system AM-200 (EB). The specific steps are as follows: the alloy is placed in the crucible of the vacuum arc furnace, vacuum is extracted to 5 Pa, and then 0.4 Pa protective gas Ar is injected; under the condition of protective atmosphere, the alloy is remelted by arc melting, and after repeated melting for 3 times, the alloy melt is quickly turned and cast into a copper mold, and after the alloy is cooled, the rod-shaped sample is taken out, and the preparation time of each sample is about 1 hour;

[0078] Step 3): The rod-shaped sample of the 1-6 alloy is cut open at a distance of 2 cm from the lower part to expose the cross section, and after the cross section is ground flat with 2000 mesh sandpaper and cleaned, XRD analysis is performed, and whether the rod-shaped alloy sample is amorphous is determined by the peak type of the XRD result, as shown in Table 1. The results are as follows: among the Φ14 mm rod-shaped samples of the 1-6 master alloys, only the 1 alloy is amorphous, and therefore the amorphous forming ability of the 1 master alloy, i.e. Dmax≥Φ14 mm; Figure 3

[0079] Step 4): The 2-6 master alloys are prepared into rod-shaped samples with a diameter of Φ12 mm by vacuum casting again, and the above steps 2) and 3) are repeated to verify whether the Φ12 mm rod-shaped sample is amorphous. Similarly, the Dmax of the 1-6 alloys is verified, and the results are shown in Table 3.

[0080] Table 3 Amorphous forming ability (Dmax) and rating evaluation results of the 1-6 master alloys max

[0081]

[0082] ​​The rating criteria of the maximum amorphous critical size method (Dmax) are as follows: when the alloy amorphous forming ability Dmax>Φ12 mm, the alloy is rated as A; when the alloy amorphous forming ability is Φ10 mm≤Dmax≤Φ12 mm, the alloy is rated as B; when the alloy amorphous forming ability is Φ8 mm≤Dmax<Φ10 mm, the alloy is rated as C; and when the alloy amorphous forming ability Dmax<Φ8 mm, the alloy is rated as D. Therefore, the rating types of the No. 1-6 master alloys are as follows: the No. 1 master alloy is rated as A, the No. 2-3 master alloys are rated as B, the No. 4-5 master alloys are rated as C, and the No. 6 master alloy is rated as D.

[0083] It should be noted that the alloy cleanliness index of Example 1 I The total oxygen content w Ot of the alloy in Comparative Example 1 Ot The corresponding relationship between the alloy amorphous forming ability (Dmax) and the alloy cleanliness index of Example 1 is shown. Among them, Comparative Example 2 is the commonly used rating method of zirconium-based amorphous master alloy, and the evaluation result is stable and reliable, and the accuracy is high, but the sample preparation and verification process is complex and time-consuming; Comparative Example 1 uses the total oxygen content w Ot of the alloy, which is fast and simple, but the total oxygen content w Ot of the alloy has no obvious corresponding relationship with the alloy amorphous forming ability, and the rating of No. 3 and No. 5 alloys is wrong, so the accuracy of this method is low; compared with Comparative Example 1, Example 1 improves the heating process, that is, the two-step ladder heating process is used instead of the direct high-temperature heating method in the conventional method, which can accurately determine the content of the base oxygen and the slag oxygen in the alloy, and the evaluation result is consistent with that of Comparative Example 2, and the cleanliness index I The alloy amorphous forming ability is inversely proportional to the alloy cleanliness index, that is, as the cleanliness index I increases, the alloy amorphous forming ability decreases, so this method is simple and fast, and has high accuracy, and is more suitable for quality control links in the smelting and production process of zirconium-based amorphous alloys.

[0084] Those skilled in the art will readily understand that the advantageous technical features of the above-mentioned methods can be freely combined and superimposed without conflict.

[0085] The above description is only the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application. The above description is only the preferred embodiments of the present application, and it should be pointed out that those skilled in the art can make several improvements and modifications without departing from the technical principles of the present application, and these improvements and modifications shall be regarded as the protection scope of the present application.

Claims

1. A method for evaluating the cleanliness of zirconium-based amorphous alloys, characterized in that, Includes the following steps: Step 1): The oxygen content in the zirconium-based amorphous alloy was determined by inert gas melting infrared analysis to obtain the content of oxygen in different forms in the zirconium-based amorphous alloy; The inert gas melting infrared analysis method employs a stepped heating method. The different forms of oxygen include matrix oxygen and oxygen in the oxide; wherein the content of the matrix oxygen is w O , and the content of the oxygen in the oxide is w Oy , in mass percent. Step 2): Calculate the cleanliness index of the zirconium-based amorphous alloy based on the oxygen content in the different forms of existence; The formula for calculating the cleanliness index of the zirconium-based amorphous alloy is as follows: I = w Oy / w Ot ; where w Oy is the content of oxygen in the oxide, w Ot is the content of matrix oxygen w O and the sum of the content of oxygen in the oxide w Oy and the content of matrix oxygen w 2. The method for evaluating the cleanliness of zirconium-based amorphous alloys according to claim 1, characterized in that, In step 1), the stepped heating includes: First heating stage: Heat to the first set temperature and maintain the temperature for the first set time; Second heating stage: Heat to the second set temperature and maintain the temperature for the second set time.

3. The method for evaluating the cleanliness of zirconium-based amorphous alloys according to claim 2, characterized in that, The first and second set temperatures are controlled by adjusting the heating power. The heating power of the first heating stage is 2500-3000W; the first set temperature is 1400-1600℃; and the first set time is 60-80s. The heating power of the second heating stage is 5000-6000W; the second set temperature is 2100-2300℃; and the second set time is 40-60s.

4. The method for evaluating the cleanliness of zirconium-based amorphous alloys according to claim 1, characterized in that, In step 1): the zirconium-based amorphous alloy is a granular zirconium-based amorphous alloy.

5. The method for evaluating the cleanliness of zirconium-based amorphous alloys according to claim 4, characterized in that, The granular zirconium-based amorphous alloy has a diameter of 3-5 mm and a weight of 0.05-0.15 g.

6. The method for evaluating the cleanliness of zirconium-based amorphous alloys according to claim 4, characterized in that, Samples are taken from the upper, middle and lower parts of the zirconium-based amorphous alloy master alloy ingot or zirconium-based amorphous alloy part, and then cut and polished to obtain the granular zirconium-based amorphous alloy.

7. The method for evaluating the cleanliness of zirconium-based amorphous alloys according to claim 1, characterized in that, In step 1): the zirconium-based amorphous alloy is a zirconium-based amorphous alloy containing rare earth elements; The rare earth element is Y.

8. The method for evaluating the cleanliness of zirconium-based amorphous alloys according to claim 1, characterized in that, In step 1): the inert gas fusion infrared analysis method uses an oxygen, nitrogen, and hydrogen analyzer; the analytical crucible used in the inert gas fusion infrared analysis method is a graphite-coated crucible; and the flux used in the inert gas fusion infrared analysis method is a nickel basket.

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