Preparation method of cadmium-zinc alloy

Abstract

The preparation method of the cadmium-zinc alloy comprises the following steps: weighing cadmium particles and zinc particles according to a molar ratio, uniformly mixing, and filling into a quartz tube; mounting the flange on the opening of the quartz tube, vacuumizing, and keeping the vacuum in the quartz tube; mounting the quartz tube with the flange into a heater of a heating furnace in a vertical posture, wherein the material is positioned in a constant-temperature area of the heater; the heating furnace runs a heating program, the constant-temperature area is heated from the room temperature until cadmium particles and zinc particles are molten, and a molten cadmium-zinc mixture is formed and kept at the constant temperature; the heating procedure is closed, the quartz tube with the flange and the molten cadmium-zinc mixture are moved out of the heating furnace, and then the quartz tube with the flange and the molten cadmium-zinc mixture are cooled to normal-temperature water in the water tank so that the molten cadmium-zinc mixture can be located below the liquid level of the water; after the molten cadmium-zinc mixture in the quartz tube is solidified into a cadmium-zinc alloy ingot and the temperature is reduced to the room temperature, the quartz tube with the flange is taken out, the flange is detached, and the cadmium-zinc alloy ingot is poured out; and longitudinally slicing the cadmium-zinc alloy ingot, sampling from the slice, and measuring the zinc content.

Description

Technical Field

[0001] The present disclosure relates to the field of cadmium zinc telluride crystal materials, and more particularly to a method for preparing cadmium zinc alloy. Background Art

[0002] Cadmium zinc alloy can be used in the preparation of cadmium zinc telluride crystal by the Traveling Heater Method (THM), which requires the higher the uniformity of zinc content in the cadmium zinc alloy, the better.

[0003] Traditionally, the melting method is adopted. The materials composed of cadmium and zinc are heated in a heating furnace above the melting point to melt and mix cadmium and zinc evenly, and then the heating is turned off to let the materials cool down to room temperature to obtain cadmium zinc alloy. However, the uniformity of zinc content in the obtained cadmium zinc alloy is poor. Therefore, it needs to be further improved to enhance the uniformity of zinc content in the cadmium zinc alloy. Summary of the Invention

[0004] In view of the problems existing in the background art, the purpose of the present disclosure is to provide a method for preparing cadmium zinc alloy, which can improve the uniformity of zinc content in the cadmium zinc alloy.

[0005] Thus, a method for preparing cadmium zinc alloy includes the steps: S1, weighing cadmium grains and zinc grains according to the molar ratio; S2, mixing the weighed cadmium grains and zinc grains evenly and loading them into a quartz tube; S3, installing a flange on the opening of the quartz tube, and using a vacuum pump to evacuate the inside of the quartz tube through a connecting pipe on the flange, and then closing the valve on the connecting pipe to maintain the vacuum inside the quartz tube; S4, installing the quartz tube with the flange in a vertical posture into the heater of the heating furnace, and the materials composed of cadmium grains and zinc grains in the quartz tube are in the constant temperature zone of the heater; S5, the heating furnace runs a heating program, and the constant temperature zone is heated from room temperature to melt the cadmium grains and zinc grains to form a molten cadmium zinc mixture, and keep it at a constant temperature; S6, turning off the heating program, removing the quartz tube with the flange together with the molten cadmium zinc mixture from the heating furnace, and then lowering it into the water at room temperature in a water tank so that the molten cadmium zinc mixture is below the water surface; S7, after the molten cadmium zinc mixture in the quartz tube solidifies into a cadmium zinc alloy ingot and the temperature drops to room temperature, taking out the quartz tube with the flange, removing the flange, and pouring out the cadmium zinc alloy ingot; S8, longitudinally slicing the cadmium zinc alloy ingot, sampling from the slice, and measuring the zinc content.

[0006] The beneficial effects of the present disclosure are as follows: In the method for preparing a cadmium-zinc alloy according to the present disclosure, in step S6, the molten cadmium-zinc mixture in the quartz tube is subjected to water quenching and cooling under the action of the normal-temperature water in the water tank through the quartz tube. The cooling rate is fast, which can effectively reduce the segregation effect during the solidification of the molten cadmium-zinc mixture, making the zinc content distribution in the obtained cadmium-zinc alloy ingot more uniform, and making the cadmium-zinc ratio of each part in the obtained cadmium-zinc alloy ingot more uniform, that is, it can improve the uniformity of the zinc content in the cadmium-zinc alloy ingot. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 is a schematic flow chart of part of the operation process of the method for preparing a cadmium-zinc alloy according to the present disclosure.

[0008] Figure 2 is a schematic diagram of longitudinal sectioning and sampling in the method for preparing a cadmium-zinc alloy according to the present disclosure. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0009] It will be understood that the disclosed embodiments are merely examples of the present disclosure, and the present disclosure can be implemented in various forms. Therefore, the specific details disclosed herein should not be construed as limiting, but only as a basis for the claims and as a representative basis for teaching those of ordinary skill in the art to implement the present disclosure in various ways.

[0010] [Method for Preparing Cadmium-Zinc Alloy]

[0011] Referring to Figure 1 and Figure 2 , the method for preparing a cadmium-zinc alloy according to the present disclosure includes the steps:

[0012] S1, weighing cadmium grains and zinc grains according to a molar ratio;

[0013] S2, mixing the weighed cadmium grains and zinc grains evenly and loading them into a quartz tube;

[0014] S3, installing a flange on the opening of the quartz tube, and using a vacuum pump to evacuate the inside of the quartz tube through a connecting pipe on the flange, and then closing the valve on the connecting pipe to maintain the vacuum inside the quartz tube;

[0015] S4, installing the quartz tube with the flange in a vertical posture into the heater of a heating furnace, and the material composed of cadmium grains and zinc grains in the quartz tube is in the constant-temperature zone of the heater;

[0016] S5, the heating furnace runs a heating program, and the constant-temperature zone is heated from room temperature to melt the cadmium grains and zinc grains to form a molten cadmium-zinc mixture, and keep it at a constant temperature;

[0017] S6. Turn off the heating program, remove the quartz tube with the flange together with the molten cadmium-zinc mixture from the heating furnace, and then lower it into the normal-temperature water in the water tank so that the molten cadmium-zinc mixture is below the water level.

[0018] S7. After the molten cadmium-zinc mixture in the quartz tube solidifies into a cadmium-zinc alloy ingot and the temperature drops to room temperature, take out the quartz tube with the flange, remove the flange, and pour out the cadmium-zinc alloy ingot.

[0019] S8. Longitudinally slice the cadmium-zinc alloy ingot, take samples from the slices, and measure the zinc content.

[0020] In the method for preparing a cadmium-zinc alloy according to the present disclosure, in step S6, the molten cadmium-zinc mixture in the quartz tube is subjected to water quenching and cooling under the action of the normal-temperature water in the water tank through the quartz tube. The cooling rate is fast, which can effectively reduce the segregation effect during the solidification of the molten cadmium-zinc mixture, making the zinc content distribution in the obtained cadmium-zinc alloy ingot more uniform, and making the cadmium-zinc ratio in each part of the obtained cadmium-zinc alloy ingot more uniform, that is, it can improve the uniformity of the zinc content in the cadmium-zinc alloy ingot. In addition, through the water quenching and cooling in step S6, the time for the molten cadmium-zinc mixture to solidify into a cadmium-zinc alloy ingot is greatly shortened, improving the efficiency and productivity of the preparation of the cadmium-zinc alloy ingot.

[0021] In step S1, for example, the molar ratio of cadmium particles to zinc particles is 96:4 or 90:10. In one example, in step S1, the purity of both cadmium particles and zinc particles is 5N.

[0022] In one example, in step S3, evacuate to below 5 Pa. In step S3, for example, the valve is a ball valve.

[0023] For example, the installation in step S4, the removal in step S6, and the lowering into the water tank can all be carried out by hoisting.

[0024] In one example, in step S5, the constant-temperature zone is heated from room temperature to 400 - 450 °C for 60 - 90 min and kept at a constant temperature for 30 - 45 min. Further, in one example, in step S5, the constant-temperature zone is heated from room temperature to 400 °C for 60 min and kept at a constant temperature for 30 min. In this way, both the heating time and the constant-temperature holding time are short, the heating and constant-temperature holding temperatures are low, improving the efficiency and productivity of the preparation and reducing the energy consumption of the preparation.

[0025] The longitudinal slicing in step S8 can be selected as slices with a certain width on both sides of the longitudinal section with the largest area (i.e., including the central axis) in the cadmium-zinc alloy ingot. Sampling within the slices in step S8 is carried out by taking evenly distributed points along the entire longitudinal center line and points equally spaced transversely from one surface of the slice, that is, the longitudinal interval is the same as the transverse interval, as Figure 2 shown. InFigure 2 Among them, 6 points are selected for sampling. That is, the center of the longitudinal center line is used as one point, and two positions close to the top edge and bottom edge of the slice and symmetric to the center of the longitudinal center line are used as two points. Thus, three positions on the longitudinal center line are determined. Horizontally, the horizontal interval of the points with the same longitudinal interval as the points is adopted, so as to determine 6 sampling points. Of course, there can be more points distributed in a rectangular array than 6 points.

[0026] [Test]

[0027] Example 1

[0028] The preparation method of the cadmium-zinc alloy in Example 1 adopts the following steps:

[0029] S1, Weigh cadmium grains and zinc grains according to the molar ratio. Among them, the molar ratio of cadmium grains to zinc grains is 96:4. The purity of both cadmium grains and zinc grains is 5N. The cadmium grains are 2929 g, the zinc grains are 71 g, and the total weight of cadmium grains and zinc grains is 3000 g;

[0030] S2, Mix the weighed cadmium grains and zinc grains evenly and then load them into a quartz tube;

[0031] S3, Install a flange on the opening of the quartz tube, and use a vacuum pump to evacuate the inside of the quartz tube to 5 pa through the connecting pipe on the flange. Then close the valve on the connecting pipe to maintain the vacuum inside the quartz tube. Among them, the valve is a ball valve;

[0032] S4, Use hoisting to install the quartz tube with the flange in a vertical posture into the heater of the heating furnace. The material composed of cadmium grains and zinc grains in the quartz tube is in the constant temperature zone of the heater;

[0033] S5, The heating furnace runs the heating program. The constant temperature zone is heated from room temperature to 400 °C in 60 min to melt the cadmium grains and zinc grains, forming a molten cadmium-zinc mixture, and keep it at a constant temperature for 30 min;

[0034] S6, Turn off the heating program, use hoisting to remove the quartz tube with the flange together with the molten cadmium-zinc mixture from the heating furnace, and then lower it into the water at room temperature in the water tank so that the molten cadmium-zinc mixture is below the water surface;

[0035] S7, After the molten cadmium-zinc mixture in the quartz tube solidifies into a cadmium-zinc alloy ingot and the temperature drops to room temperature, use hoisting to take out the quartz tube with the flange, remove the flange, and pour out the cadmium-zinc alloy ingot;

[0036] S8. Longitudinally slice the cadmium-zinc alloy ingot, take samples from the slices, and measure the zinc content. Among them, for longitudinal slicing, select slices with a certain width on both sides of the longitudinal section with the largest area (i.e., including the central axis) in the cadmium-zinc alloy ingot. Select 6 points for sampling, that is, take the center of the longitudinal center line from one surface of the slice as one point, and two positions symmetric to the center of the longitudinal center line and close to the top and bottom edges of the slice as two points, thereby determining three positions on the longitudinal center line. Horizontally, use the same horizontal interval as the longitudinal interval of the points, take samples at each point, and use inductively coupled plasma atomic emission spectrometry (ICP-AES) to measure the zinc content.

[0037] Example 2

[0038] Except that in step S1, the purity of both cadmium grains and zinc grains is 5N, the molar ratio of cadmium grains to zinc grains is 90:10, the weight of cadmium grains is 2817.85 g, the weight of zinc grains is 182.15 g, and the total weight of cadmium grains and zinc grains is 3000 g, the rest is the same as in Example 1. That is, in Example 2, only the molar ratio of cadmium grains and zinc grains in the materials and the corresponding weights are changed.

[0039] Comparative Example 1

[0040] Except that step S6 is changed to "turn off the heating program", and step S7 is changed to "use hoisting to take out the quartz tube with a flange and place the quartz tube in the air. After the molten cadmium-zinc mixture in the quartz tube solidifies into a cadmium-zinc alloy ingot and the temperature drops to room temperature in the air, remove the flange and pour out the cadmium-zinc alloy ingot", the rest is the same as in Example 1. That is, in Comparative Example 1, air quenching in the air is used to replace the water quenching and cooling in the water tank in Example 1.

[0041] Comparative Example 2

[0042] Except that in step S1, the purity of both cadmium grains and zinc grains is 5N, the molar ratio of cadmium grains to zinc grains is 90:10, the weight of cadmium grains is 2817.85 g, the weight of zinc grains is 182.15 g, and the total weight of cadmium grains and zinc grains is 3000 g, step S6 is changed to "turn off the heating program, do not raise the quartz tube, and let the quartz tube remain in the heating furnace", and step S7 is changed to "after the molten cadmium-zinc mixture in the quartz tube solidifies into a cadmium-zinc alloy ingot with the heating furnace cooling down together and the temperature drops to room temperature, use hoisting to take out the quartz tube with a flange, remove the flange, and pour out the cadmium-zinc alloy ingot", the rest is the same as in Example 1. In other words, Comparative Example 2 uses furnace cooling to replace the water quenching and cooling in the water tank in Example 2.

[0043] Table 1 shows the measurement of the zinc content of Samples 1 to 6 for six samplings of Examples 1-2 and Comparative Examples 1-2. Among them, when the molar ratio of cadmium grains to zinc grains is 96:4, the theoretical mass ratio of zinc in the total mass of cadmium and zinc is 2.37%; when the molar ratio of cadmium grains to zinc grains is 90:10, the theoretical mass ratio of zinc in the total mass of cadmium and zinc is 2.37%; the variance of the measured zinc content of the six samples is calculated with the theoretical value.

[0044] Table 1 Measurement results of the zinc content of six samples in Examples 1-2 and Comparative Examples 1-2

[0045]

[0046] Compared with Comparative Example 1 using air quenching, in the obtained cadmium-zinc alloy ingot, the uniformity of the zinc content of the sample of Example 1 using water quenching for cooling is high.

[0047] Compared with Comparative Example 2 using furnace cooling, in the obtained cadmium-zinc alloy ingot, the uniformity of the zinc content of the sample of Example 2 using water quenching for cooling is high.

[0048] That is to say, in the obtained cadmium-zinc alloy ingot, the uniformity of the zinc content obtained by using the water quenching cooling method is higher than the uniformity of the zinc content obtained by using air quenching and the uniformity of the zinc content obtained by using furnace cooling.

[0049] Multiple exemplary embodiments are described with the detailed description above, but the present disclosure is not intended to be limited to the explicitly disclosed combinations. Therefore, unless otherwise specified, the various features disclosed herein can be combined together to form multiple additional combinations not shown for the purpose of brevity.

Claims

1. A method for preparing a cadmium-zinc alloy, characterized in that, Including the steps: S1. Weigh cadmium granules and zinc granules according to the molar ratio; S2. Mix the weighed cadmium granules and zinc granules and then load them into a quartz tube; S3. Install a flange on the opening of the quartz tube, and use a vacuum pump to evacuate the inside of the quartz tube through the connecting pipe on the flange. Then close the valve on the connecting pipe to maintain the vacuum inside the quartz tube; S4. Install the quartz tube with the flange in a vertical position into the heater of the heating furnace, and the material composed of cadmium granules and zinc granules in the quartz tube is in the constant temperature zone of the heater; S5. The heating furnace runs the heating program, and the constant temperature zone is heated from room temperature to melt the cadmium granules and zinc granules to form a molten cadmium-zinc mixture, and keep it at a constant temperature; S6. Turn off the heating program, remove the quartz tube with the flange together with the molten cadmium-zinc mixture from the heating furnace, and then lower it into the water at room temperature in the water tank so that the molten cadmium-zinc mixture is below the water level; S7. After the molten cadmium-zinc mixture in the quartz tube solidifies into a cadmium-zinc alloy ingot and the temperature drops to room temperature, take out the quartz tube with the flange, remove the flange, and pour out the cadmium-zinc alloy ingot; S8. Make longitudinal sections of the cadmium-zinc alloy ingot, take samples from the sections, and measure the zinc content.

2. The method for preparing cadmium-zinc alloy according to claim 1, wherein: In step S1, the molar ratio of cadmium granules to zinc granules is 96:4 or 90:

10.

3. The method for preparing cadmium-zinc alloy according to claim 1, wherein: In step S1, the purity of both cadmium granules and zinc granules is 5N.

4. The method for preparing cadmium-zinc alloy according to claim 1, wherein: In step S3, evacuate to below 5 Pa.

5. The method for preparing cadmium-zinc alloy according to claim 1, wherein: In step S5, the constant temperature zone is heated from room temperature for 60 - 90 min to 400 - 450 °C and kept at a constant temperature for 30 - 45 min.

6. The method for preparing cadmium-zinc alloy according to claim 1, wherein: In step S5, the constant temperature zone is heated from room temperature for 60 min to 400 °C and kept at a constant temperature for 30 min.

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