A method for evaluating the performance changes of SmCo permanent magnet alloys under nuclear environment conditions

Abstract

A method for evaluating the performance changes of SmCo permanent magnet alloys under nuclear environmental conditions relates to a method for evaluating the performance of permanent magnet alloys. The present invention aims to solve the problem in the prior art that the performance changes of SmCo permanent magnet alloys cannot be evaluated due to the fact that the materials are affected by both the irradiation field and the temperature field under a nuclear environment. The sample of the present invention is placed in a cast copper heater, and the sample and the cast copper heater are placed in a vacuum chamber. The performance of the SmCo permanent magnet alloy is tested by implementing a working environment in which irradiation and temperature act together through a temperature measurement and control system. The accuracy of the service stability evaluation of SmCo alloy materials under a nuclear environment is improved. The present invention is used for the performance evaluation of permanent magnet alloys.

Description

Technical Field

[0001] The invention relates to a method for evaluating the performance of a permanent magnet alloy, in particular to a method for evaluating the performance change of a SmCo permanent magnet alloy under nuclear environment conditions, and belongs to the technical field of permanent magnet alloys. Background Art

[0002] SmCo permanent magnet alloys are widely used in nuclear power instrumentation, particle accelerators, and synchrotron radiation devices. When used in nuclear power plant environments, SmCo permanent magnet alloys are often exposed to high temperatures and various radiation environments, such as neutron irradiation and gamma ray irradiation. In these environments, the service stability of SmCo permanent magnet alloys is directly related to the normal operation and use of the equipment.

[0003] Currently, most studies on the performance changes of SmCo permanent magnet alloys have only considered the influence of a single factor, namely temperature stability and radiation resistance. However, since SmCo permanent magnet alloys are mainly affected by a complex environment in the actual nuclear environment, namely the simultaneous presence of nuclear radiation and high temperature environment, only exploring the influence of a single factor cannot accurately evaluate the law of their performance changes. Therefore, developing an engineering method that considers the impact of the real working environment on the performance changes of SmCo permanent magnet alloys is an urgent problem to be solved in the performance evaluation of SmCo permanent magnet alloys. It has also become a basic demand of this research field and has important significance for both basic science and nuclear industry applications.

[0004] In summary, the existing engineering methods have the problem of inaccurate service stability evaluation of SmCo permanent magnet alloys in actual nuclear environments. Summary of the Invention

[0005] The purpose of the present invention is to solve the problem that the engineering methods in the prior art are not accurate enough in evaluating the service stability of SmCo permanent magnet alloys under actual nuclear environments, and further provide a method for evaluating the performance changes of SmCo permanent magnet alloys under nuclear environmental conditions.

[0006] The technical solution of the present invention is:

[0007] A method for evaluating performance changes of SmCo permanent magnet alloys under nuclear environmental conditions comprises the following steps:

[0008] Step 1: Record the SmCo permanent magnet alloy sample and place it in the groove of the cast copper heater. Fill the remaining part of the groove with refractory asbestos and cover the groove with an aluminum silicate ceramic fiber insulation board.

[0009] Step 2: Place the cast copper heater in front of the irradiation window of the vacuum chamber, connect the power cord, thermocouple probe and inlet and outlet pipes, and then seal the vacuum chamber to a sealed state.

[0010] Step 3: Use a protective atmosphere such as nitrogen or argon to purge the chamber by filling and deflating the chamber. Adjust the temperature of the external temperature control system to the experimental set temperature. Wait for the heater temperature to reach the set temperature and then maintain the temperature until the temperature reading stabilizes.

[0011] Step 4: Determine the irradiation time based on the preset radiation dose and begin the irradiation experiment. After the predetermined time has elapsed, stop irradiation and wait until the radiation level drops below the safe range. Remove the experimental equipment and samples. Immediately perform a performance test on the test samples, comparing the performance changes before and after the experimental treatment.

[0012] Compared with the prior art, the present invention has the following effects:

[0013] This study simulates the complex experimental conditions of SmCo permanent magnet alloys in a nuclear environment using an experimental setup combined with irradiation equipment. The sample, along with a cast copper heater, is placed in a vacuum chamber, creating a working environment where irradiation and temperature interact to test the performance of the SmCo permanent magnet alloy. This approach improves the accuracy of evaluating the service stability of SmCo permanent magnet alloys in actual nuclear environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the complex nuclear environment simulation experimental device of the present invention.

[0015] In the figure: 1. SmCo permanent magnet alloy sample, 2. cast copper heater, 3. vacuum chamber, 4. power cord, 5. air inlet pipe, 6. air outlet pipe, 7. thermocouple probe, 8. external temperature control system. DETAILED DESCRIPTION

[0016] In order to make the purpose, features, and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0017] The technical solution of the present invention will be further described below with reference to the accompanying drawings and through specific implementation methods.

[0018] Specific implementation method 1: Combination Figure 1 This embodiment describes a method for evaluating the performance change of a SmCo permanent magnet alloy under nuclear environment conditions, which includes the following steps:

[0019] Step 1: Record the SmCo permanent magnet alloy sample 1 and place it in the groove of the cast copper heater 2. Fill the remaining part of the groove of the cast copper heater 2 with refractory asbestos, and cover the groove with an aluminum silicate ceramic fiber insulation board;

[0020] The refractory asbestos in this embodiment is resistant to high temperatures. In actual use, the refractory asbestos must fill the heater groove to improve the heat preservation effect in the groove of the cast copper heater 2.

[0021] The size of the aluminum silicate ceramic fiber insulation board of this embodiment is customized according to the size of the groove, so as to improve the temperature stability of the SmCo permanent magnet alloy sample 1 during the experiment.

[0022] Step 2: Place the cast copper heater 2 in front of the irradiation window of the vacuum chamber 3, connect the power cord 4, thermocouple probe 7 and the inlet and outlet pipes 6, and then seal the vacuum chamber 3 until it is sealed;

[0023] Step 3: Use a protective atmosphere such as nitrogen or argon to purge the chamber by filling and deflating the chamber. Adjust the temperature of the external temperature control system to the experimental set temperature. Wait for the heater temperature to reach the set temperature and then maintain the temperature until the temperature reading stabilizes.

[0024] Step 4: Determine the irradiation time based on the preset radiation dose and begin the irradiation experiment. After the predetermined time has elapsed, stop irradiation and wait until the radiation level drops below the safe range. Remove the experimental equipment and samples. Immediately perform a performance test on the test samples, comparing the performance changes before and after the experimental treatment.

[0025] Specific implementation method 2: Combination Figure 1 To illustrate this embodiment, the SmCo permanent magnet alloy sample 1 of this embodiment is provided with a parallel sample, preferably, a single parallel sample. This arrangement prevents accidental errors in the sample. Other components and connections are the same as those in the first embodiment.

[0026] Specific implementation method three: Combination Figure 1 This embodiment describes a protective atmosphere that purges the chamber multiple times, with the chamber being purge-treated and de-purge-treated. Preferably, the purge cycle is performed four to five times. This ensures that air in the chamber is exhausted before heating, preventing oxidation of the experimental sample. Other components and connections are the same as those in Specific Embodiments 1 or 2.

[0027] Specific implementation method four: Combination Figure 1 This embodiment describes a sample holding time of 5 to 10 minutes. This ensures that the sample is fully and evenly heated to the set experimental temperature before irradiation begins, thereby improving experimental accuracy. Other components and connections are identical to those in Specific Embodiments 1, 2, or 3.

[0028] Specific implementation method five: Combination Figure 1 This embodiment describes the sample irradiation time of 10 to 100 minutes. This setting satisfies the experimental working conditions. The other components and connections are the same as those of the first, second, third, or fourth embodiments.

[0029] The present invention has been disclosed above with reference to preferred embodiments, but this is not intended to limit the present invention. Any simple modification, equivalent change, and modification made to the above embodiments by any person skilled in the art without departing from the content of the technical solution of the present invention and based on the technical essence of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A method for evaluating the performance changes of SmCo permanent magnet alloys under nuclear environment conditions, characterized by: It includes the following steps: Step 1: record the SmCo permanent magnet alloy sample (1) and place it in the groove of the cast copper heater (2), fill the remaining part of the groove of the cast copper heater (2) with refractory asbestos, and cover the groove with an aluminum silicate ceramic fiber insulation board; Step 2: Place the cast copper heater (2) in front of the irradiation window of the vacuum chamber (3), connect the power cord (4), the thermocouple probe (7), and the inlet and outlet pipes (6), and then seal the vacuum chamber (3) to a sealed state; Step 3: Use nitrogen or argon protective atmosphere to purge the cavity by filling and deflating the cavity to fill it with protective atmosphere; adjust the temperature of the external temperature control system to the experimental set temperature, wait for the heater temperature to reach the set temperature, and then keep the temperature until the temperature reading is stable. The holding time is 5 to 10 minutes; Step 4: Determine the irradiation time based on the preset irradiation dose of the experiment and start the irradiation experiment. The irradiation time is 10 to 100 minutes. Stop irradiation after the time is up. When the radiation drops below the safe range, remove the experimental equipment and samples, and then immediately perform a performance test on the samples to compare the performance changes before and after the experimental treatment.

2. The method for evaluating the performance change of SmCo permanent magnet alloy under nuclear environment conditions according to claim 1, characterized in that: The sample in step 1 is provided with one parallel sample.

3. The method for evaluating the performance change of SmCo permanent magnet alloy under nuclear environment conditions according to claim 1, characterized in that: In step 3, the cavity is subjected to a gas cleaning treatment of filling and degassing with a protective atmosphere 4 to 5 times.

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