CN118010597B - Device and method for testing helium permeability of glass material for quantum vacuum measurement standard - Google Patents

Abstract

The present application relates to a device and method for testing the helium permeability of glass materials used for quantum vacuum metrology standards, including: a first fine-tuning vacuum valve, a capacitance film vacuum gauge, an inflatable chamber, a second fine-tuning vacuum valve, a magnetic levitation rotor vacuum gauge, a test chamber A, a first vacuum valve, a test chamber B, a quadrupole mass spectrometer, a helium bottle, a second vacuum valve, a first vacuum pumping unit, a third vacuum valve, a glass material to be tested, a fourth vacuum valve, a KF interface, and a second vacuum pumping unit. The embodiment of the present application utilizes the good stability of the magnetic levitation rotor vacuum gauge to perform online calibration of the mass spectrometer for measuring the helium partial pressure used for testing, thereby solving the problem of excessive deviation in the measurement of the helium partial pressure caused by non-ideal factors such as poor stability and repeatability of the mass spectrometer, and effectively reducing the uncertainty of the measurement of the helium permeability of the glass materials used for quantum vacuum metrology standards.

Description

A device and method for testing the helium permeability of glass materials used in quantum vacuum metrology standards

Technical Field

The present invention relates to the technical field of supplying standard gas, and more specifically, to a device and method for testing the helium permeability of glass materials used for quantum vacuum metrology standards.

Background technique

The document "Research on the Refractive Index Measurement of Non-polar Rare Gases in Quantum Vacuum Metrology Standards, Acta Physica Sinica, Vol. 70, No. 4, April 2021, pp. 040601-1-9" introduces the medium and low vacuum quantum metrology standard device and method based on optical interferometry. The document points out that the stability of the physical length of the Fabry-Perot optical resonator, as the core component of the device, has an important correlation with the performance of the device, and it is required to have good thermal stability. Therefore, ULE (Ultra Low Expansion) and Zerodur glass materials are widely used to make the resonator; at the same time, given that He is the gas with the highest accuracy in calculating microscopic polarization parameters, the standard requires the use of helium for experiments, but this type of glass material has high adsorption and diffusion characteristics for helium, which is manifested macroscopically as a permeability parameter. Therefore, accurate measurement and evaluation of this parameter plays an important role in improving the metrological characteristics of the device. There is no unified and recognized method and device for permeability testing of this type of material He at home and abroad.

Summary of the invention

The embodiments of the present application provide a device and method for testing the helium permeability of glass materials for quantum vacuum metrology standards. In order to have a basic understanding of some aspects of the disclosed embodiments, a simple summary is given below. This summary is not a general review, nor is it intended to identify key/important components or describe the scope of protection of these embodiments. Its only purpose is to present some concepts in a simple form as a preface to the detailed description that follows.

In a first aspect, an embodiment of the present application provides a helium permeability test device for glass materials used in quantum vacuum metrology standards, the device comprising: a first fine-tuning vacuum valve, a capacitance film vacuum gauge, an inflatable chamber, a second fine-tuning vacuum valve, a magnetic levitation rotor vacuum gauge, a test chamber A, a first vacuum valve, a test chamber B, a quadrupole mass spectrometer, a helium bottle, a second vacuum valve, a first vacuum pumping unit, a third vacuum valve, a glass material to be tested, a fourth vacuum valve, a KF interface, and a second vacuum pumping unit, wherein:

The helium cylinder is connected to the inflation chamber, and the second vacuum valve and the first fine-tuning vacuum valve are sequentially arranged on the connected pipeline;

The gas-filled chamber is connected to the capacitance film vacuum gauge and the first vacuum pumping unit, and the pipeline connected to the first vacuum pumping unit is provided with the third vacuum valve;

The inflation chamber is connected to the test chamber A, a second fine-tuning vacuum valve is provided on one of the connected pipelines, and the KF interface and the tested glass material are provided on the other pipeline;

The test chamber A is connected to the magnetic suspension rotor vacuum gauge;

The test chamber A is connected to the test chamber B, and the first vacuum valve is provided on the connecting pipeline;

The test chamber B is connected to the quadrupole mass spectrometer and the second vacuum pumping unit, and the fourth vacuum valve is provided on the pipeline connected to the second vacuum pumping unit;

The test chamber A and the test chamber B have the same volume and are made of the same material.

According to a preferred embodiment, the glass material to be tested is in the shape of a circular thin sheet with a diameter ranging from 30 mm to 40 mm and a thickness ranging from 2 mm to 3 mm.

According to a preferred embodiment, the minimum detectable partial pressure of the quadrupole mass spectrometer is less than or equal to 1×10 ⁻¹⁰ Pa.

According to a preferred embodiment, the measurement accuracy of the capacitance diaphragm vacuum gauge should be within ±0.15%.

According to a preferred embodiment, the stability of the magnetically suspended rotor vacuum gauge is less than or equal to 1% per year.

According to another aspect of a preferred embodiment, the present application provides a method for testing the helium permeability of a glass material for a quantum vacuum metrology standard, the method comprising:

Step 1, fixing the glass material to be tested on the KF interface;

Step 2, start the first vacuum pumping unit and the second vacuum pumping unit, open the first vacuum valve, the third vacuum valve, and the fourth vacuum valve, evacuate the gas-filled chamber, the test chamber A, the test chamber B, and the connecting pipeline, turn on the capacitance film vacuum gauge connected to the gas-filled chamber and the magnetic suspension rotor vacuum gauge connected to the test chamber A, and when the pressure in the test chamber A and the test chamber B is lower than the order of ^10-2 Pa, turn on the quadrupole mass spectrometer;

Step 3, continuously evacuating the air in the inflation chamber, the test chamber A, and the test chamber B to reach the ultimate vacuum degree;

Step 4, after the quadrupole mass spectrometer, the capacitance film vacuum gauge, and the magnetic levitation rotor vacuum gauge are stable for more than 24 hours, the third vacuum valve and the fourth vacuum valve are closed, and the capacitance film vacuum gauge and the magnetic levitation rotor vacuum gauge are zeroed and residual damping is deducted respectively;

Step 5, opening the second vacuum valve, adjusting the first fine-tuning vacuum valve, filling the gas-filled chamber with helium from the helium bottle, adjusting the inlet pressure according to the test requirements, and recording the corresponding indication of the capacitance film vacuum gauge;

Step 6, recording the initial indication of the magnetic levitation rotor vacuum gauge and the initial value of the helium partial pressure ion flow of the quadrupole mass spectrometer, adjusting the second fine-tuning vacuum valve until the indication of the magnetic levitation rotor vacuum gauge reaches the order of ^10-2 Pa, and recording the indications of the magnetic levitation rotor vacuum gauge and the quadrupole mass spectrometer at this time;

Step 7, calculating the helium sensitivity of the quadrupole mass spectrometer according to the data measured in step 6;

Step 8, opening the fourth vacuum valve, and re-evacuating the test chamber A and the test chamber B to the ultimate vacuum degree;

Step 9, closing the first vacuum valve and the fourth vacuum valve, and recording the change in the ion current of the quadrupole mass spectrometer within 5 min to 180 min;

Step 10, open the first vacuum valve and repeat step 8;

Step 11, closing the fourth vacuum valve, recording the initial ion current value of the quadrupole mass spectrometer, and after the time used in step 9, recording the value of the ion current of the quadrupole mass spectrometer after it rises due to the helium penetration of the measured glass material;

Step 12, calculating the permeability of the glass material being tested.

According to a preferred embodiment, before step 2, the method further includes: leak testing the glass material to be tested and the KF interface to ensure that they meet the requirements.

The technical solution provided by the embodiments of the present application may have the following beneficial effects:

In an embodiment of the present application, a helium permeability test device for a glass material used as a quantum vacuum metrology standard comprises: a first fine-tuning vacuum valve, a capacitance film vacuum gauge, an inflation chamber, a second fine-tuning vacuum valve, a magnetic levitation rotor vacuum gauge, a test chamber A, a first vacuum valve, a test chamber B, a quadrupole mass spectrometer, a helium bottle, a second vacuum valve, a first vacuum pumping unit, a third vacuum valve, a glass material to be tested, a fourth vacuum valve, a KF interface, and a second vacuum pumping unit, wherein: the helium bottle is connected to the inflation chamber, and the second vacuum valve and the first fine-tuning vacuum valve are sequentially arranged on the connected pipeline; the capacitance film vacuum gauge and the first vacuum pump are connected to the inflation chamber. The gas unit is connected to the first vacuum pumping unit, and the third vacuum valve is arranged on the pipeline connected to the first vacuum pumping unit; the inflation chamber is connected to the test chamber A, and a second fine-tuning vacuum valve is arranged on one of the connected pipelines, and the KF interface and the glass material to be tested are arranged on the other pipeline; the test chamber A is connected to the magnetic levitation rotor vacuum gauge; the test chamber A is connected to the test chamber B, and the first vacuum valve is arranged on the connected pipeline; the test chamber B is connected to the quadrupole mass spectrometer and the second vacuum pumping unit, and the fourth vacuum valve is arranged on the pipeline connected to the second vacuum pumping unit; the test chamber A and the test chamber B have the same volume and the same material. The method for testing the helium permeability of a glass material for a quantum vacuum metrology standard comprises: step 1, fixing the glass material to be tested on the KF interface; step 2, starting the first vacuum pumping unit and the second vacuum pumping unit, opening the first vacuum valve, the third vacuum valve, and the fourth vacuum valve, and evacuating the gas-filled chamber, the test chamber A, the test chamber B, and the connecting pipeline, and opening the capacitance film vacuum gauge connected to the gas-filled chamber and the magnetic suspension rotor vacuum gauge connected to the test chamber A. When the pressure in the test chamber A and the test chamber B is lower than 10 ^-2 When the vacuum level reaches the order of Pa, the quadrupole mass spectrometer is turned on; step 3, the inflatable chamber, the test chamber A, and the test chamber B are continuously evacuated to reach the ultimate vacuum degree; step 4, when the quadrupole mass spectrometer, the capacitance film vacuum gauge, and the magnetic levitation rotor vacuum gauge are stable for more than 24 hours, the third vacuum valve and the fourth vacuum valve are closed, and the capacitance film vacuum gauge and the magnetic levitation rotor vacuum gauge are zeroed and residual damping is deducted respectively; step 5, the second vacuum valve is opened, the first fine-tuning vacuum valve is adjusted, helium is filled into the inflatable chamber from the helium bottle, the intake pressure is adjusted according to the test requirements, and the corresponding indication of the capacitance film vacuum gauge is recorded; step 6, the initial indication of the magnetic levitation rotor vacuum gauge and the initial value of the helium partial pressure ion flow of the quadrupole mass spectrometer are recorded, and the second fine-tuning vacuum valve is adjusted until the indication of the magnetic levitation rotor vacuum gauge reaches 10 ^-2 Pa level, record the indications of the magnetic levitation rotor vacuum gauge and the quadrupole mass spectrometer at this time; step 7, calculate the helium sensitivity of the quadrupole mass spectrometer according to the data measured in step 6; step 8, open the fourth vacuum valve, and re-evacuate the test chamber A and the test chamber B to the ultimate vacuum degree; step 9, close the first vacuum valve and the fourth vacuum valve, and record the change in the ion flow of the quadrupole mass spectrometer within 5min~180min; step 10, open the first vacuum valve and repeat step 8; step 11, close the fourth vacuum valve, record the initial ion flow value of the quadrupole mass spectrometer, and after the time used in step 9, record the value of the ion flow of the quadrupole mass spectrometer after the increase caused by the helium penetration of the glass material to be tested; step 12, calculate the permeability of the glass material to be tested. The helium permeability testing device and method for glass materials used for quantum vacuum metrology standards described in the embodiments of the present application adopt an in-situ calibration method to provide a more accurate test pressure indication for the helium permeability test, thereby realizing the precise measurement of the helium permeability of glass materials used for quantum vacuum metrology standards, and solving the problem that the helium permeability characteristics of existing glass materials used for quantum vacuum metrology standards are difficult to evaluate. The embodiments of the present application utilize the good stability of the magnetic levitation rotor vacuum gauge to perform online calibration on the mass spectrometer used for measuring the helium partial pressure for testing, thereby solving the problem of excessive deviation in the helium partial pressure measurement caused by non-ideal factors such as poor stability and repeatability of the mass spectrometer, and effectively reducing the uncertainty in the measurement of the helium permeability of the glass materials used for quantum vacuum metrology standards.

It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

FIG1 is a schematic structural diagram of a device for testing helium permeability of glass materials for quantum vacuum metrology standards provided in an embodiment of the present application;

FIG2 is a flow chart of a method for testing the helium permeability of a glass material for a quantum vacuum metrology standard provided in an embodiment of the present application.

Figure numerals: 1-first fine-tuning vacuum valve; 2-capacitance film vacuum gauge; 3-inflatable chamber; 4-second fine-tuning vacuum valve; 5-magnetic levitation rotor vacuum gauge; 6-test chamber A; 7-first vacuum valve; 8-test chamber B; 9-quadrupole mass spectrometer; 10-helium bottle; 11-second vacuum valve; 12-first vacuum pumping unit; 13-third vacuum valve; 14-KF interface; 15-tested glass material; 16-fourth vacuum valve; 17-second vacuum pumping unit.

Detailed ways

The following description and the drawings sufficiently illustrate specific embodiments of the invention to enable those skilled in the art to practice them.

It should be clear that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are only examples of systems and methods consistent with some aspects of the present invention as detailed in the attached claims.

In the description of the present invention, it should be understood that the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In addition, in the description of the present invention, unless otherwise specified, "plurality" refers to two or more. "And/or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and/or B can represent: A exists alone, A and B exist at the same time, and B exists alone. The character "/" generally indicates that the previously associated objects are in an "or" relationship.

A device and method for testing helium permeability of glass materials for quantum vacuum metrology standards provided in an embodiment of the present application will be described in detail below in conjunction with FIGS. 1-2 .

Please refer to Figure 1, which is a schematic diagram of the structure of a helium permeability test device for glass materials used as quantum vacuum metrology standards in an embodiment of the present application. As shown in Figure 1, a helium permeability test device for glass materials used as quantum vacuum metrology standards in an embodiment of the present application may include: a first fine-tuning vacuum valve 1, a capacitance film vacuum gauge 2, an inflatable chamber 3, a second fine-tuning vacuum valve 4, a magnetic levitation rotor vacuum gauge 5, a test chamber A 6, a first vacuum valve 7, a test chamber B 8, a quadrupole mass spectrometer 9, a helium bottle 10, a second vacuum valve 11, a first vacuum pumping unit 12, a third vacuum valve 13, a glass material to be tested 15, a fourth vacuum valve 16, a KF interface 14, and a second vacuum pumping unit 17, wherein:

The helium cylinder 10 is connected to the inflation chamber 3, and the second vacuum valve 11 and the first fine-tuning vacuum valve 1 are sequentially arranged on the connecting pipeline;

The gas-filled chamber 3 is connected with a capacitance film vacuum gauge 2 and a first vacuum pumping unit 12, and a third vacuum valve 13 is arranged on the pipeline connected with the first vacuum pumping unit 12;

The inflation chamber 3 is connected to the test chamber A 6, and a second fine-tuning vacuum valve 4 is provided on one of the connected pipelines, and a KF interface 14 and a glass material to be tested 15 are provided on the other pipeline;

The test chamber A 6 is connected to a magnetically suspended rotor vacuum gauge 5;

The test chamber A 6 is connected to the test chamber B 8, and a first vacuum valve 7 is provided on the connecting pipeline;

The test chamber B 8 is connected to a quadrupole mass spectrometer 9 and a second vacuum pumping unit 17, and a fourth vacuum valve 16 is provided on the pipeline connected to the second vacuum pumping unit 17;

Test chamber A 6 and test chamber B 8 have the same volume and the same material.

Specifically, in the embodiment of the present application, the measured glass material 15 is in the shape of a circular thin sheet with a diameter ranging from 30 mm to 40 mm and a thickness ranging from 2 mm to 3 mm. The material used in the embodiment of the present application is Zerodur with a diameter of 40 mm and a thickness of 2 mm; the first vacuum pumping unit 12 and the second vacuum pumping unit 17 are LEYBOLD SC15D and LEYBOLD i600 respectively; the first vacuum valve 7, the third vacuum valve 13, and the fourth vacuum valve 16 are all VAT 54; the quadrupole mass spectrometer 9 is PFEIFFER QMG220, and the minimum detectable partial pressure of the quadrupole mass spectrometer 9 is less than or equal to 1×10 ^-10 Pa; the capacitance film vacuum gauge 2 is INFICON CUBE1000Torr, and the measurement accuracy of the capacitance film vacuum gauge 2 should be within ±0.15%; the magnetic levitation rotor vacuum gauge 5 is MKS SRG-3, and the stability of the magnetic levitation rotor vacuum gauge 5 is less than or equal to 1%/year; the first fine-tuning vacuum valve 1 is VARIAN DN40.

Embodiment 1:

The present application embodiment provides a flow chart of a method for testing the helium permeability of a glass material for a quantum vacuum metrology standard. As shown in FIG2 , the method of the present application embodiment may include the following steps:

Step 1, fixing the glass material 15 to be tested on the KF interface 14;

Step 2, start the first vacuum pumping unit 12, the second vacuum pumping unit 17, open the first vacuum valve 7, the third vacuum valve 13, the fourth vacuum valve 16, and evacuate the gas-filled chamber 3, the test chamber A 6, the test chamber B 8 and the connecting pipeline, turn on the capacitance film vacuum gauge 2 connected to the gas-filled chamber 3, and the magnetic suspension rotor vacuum gauge 5 connected to the test chamber A 6, and when the pressure in the test chamber A 6 and the test chamber B 8 is evacuated to 8.7×10 ^-3 Pa, turn on the quadrupole mass spectrometer 9. Before step 2, it also includes:

The glass material 15 and the KF interface 14 to be tested are leak tested to ensure that they meet the requirements. In the embodiment of the present application, the leak rate is measured to be 5.2×10 ^-12 Pam ³ /s, which meets the requirements.

Step 3, through continuous evacuation, the inflation chamber 3, the test chamber A 6, and the test chamber B 8 reach the ultimate vacuum degree of 1.8×10 ^-6 Pa;

Step 4, after the quadrupole mass spectrometer 9, the capacitance film vacuum gauge 2, and the magnetic suspension rotor vacuum gauge 5 are stable for 28 hours, the third vacuum valve 13 and the fourth vacuum valve 16 are closed, and the capacitance film vacuum gauge 2 and the magnetic suspension rotor vacuum gauge 5 are zeroed and residual damping is deducted respectively;

Step 5, open the second vacuum valve 11, adjust the first fine-tuning vacuum valve 1, fill the gas chamber 3 with helium from the helium bottle 10, adjust the inlet pressure according to the test requirements, and record the corresponding reading of the capacitance film vacuum gauge 2 as 1.03×10 ⁵ Pa;

Step 6, record the initial indication of the magnetic suspension rotor vacuum gauge 5 p _SRG0 =4.5623×10 ^-5 Pa, the initial value of the helium partial pressure ion flow I ₀ =1.6984×10 ^-13 A of the quadrupole mass spectrometer 9, adjust the second fine-tuning vacuum valve 4 until the indication of the magnetic suspension rotor vacuum gauge 5 p _SRG =2.8182×10 ^-2 Pa, the indication of the helium partial pressure ion flow I of the quadrupole mass spectrometer 9 =6.0862×10 ^-5 A, and record the indications of the magnetic suspension rotor vacuum gauge 5 and the quadrupole mass spectrometer 9 at the same time;

Step 7, based on the data measured in step 6, calculate the helium sensitivity of the quadrupole mass spectrometer 9. In the embodiment of the present application, the helium sensitivity of the quadrupole mass spectrometer 9 is calculated according to formula ① S _He = 2.16×10 ^-3 A/Pa;

Step 8, open the fourth vacuum valve 16, and re-evacuate the test chamber A 6 and the test chamber B 8 to the ultimate vacuum degree of 1.9×10 ^-6 Pa;

Step 9, close the first vacuum valve 7 and the fourth vacuum valve 16, and record the change in the ion flow of the quadrupole mass spectrometer 9 within 5 minutes. =2.5367×10 ^-13 A;

Step 10, open the first vacuum valve 7, and repeat step 8;

Step 11, close the fourth vacuum valve 16, record the initial ion current value I _i =1.8225×10 ^-13 A of the quadrupole mass spectrometer 9, and after 5 minutes, record the value of the ion current of the quadrupole mass spectrometer 9 after the increase caused by the helium penetration of the measured glass material, I _f =5.5395×10 ^-12 A;

Step 12, calculating the permeability of the glass material 15 to be tested. Specifically, according to formula ②, it is calculated that K=1.18×10 ^-15 cm ² /s.

Embodiment 2:

The method of the embodiment of the present application may include the following steps:

Step 1, fixing the glass material 15 to be tested on the KF interface 14;

Step 2, start the first vacuum pumping unit 12, the second vacuum pumping unit 17, open the first vacuum valve 7, the third vacuum valve 13, the fourth vacuum valve 16, and evacuate the gas-filled chamber 3, the test chamber A 6, the test chamber B 8 and the connecting pipeline, turn on the capacitance film vacuum gauge 2 connected to the gas-filled chamber 3, and the magnetic suspension rotor vacuum gauge 5 connected to the test chamber A 6, and when the pressure in the test chamber A 6 and the test chamber B 8 is evacuated to 9.97×10 ^-3 Pa, turn on the quadrupole mass spectrometer 9. Before step 2, it also includes:

The glass material 15 and the KF interface 14 to be tested are leak tested to ensure that they meet the requirements. In the embodiment of the present application, the leak rate is measured to be 4.9×10 ^-12 Pam ³ /s, which meets the requirements.

Step 3, through continuous evacuation, the inflation chamber 3, the test chamber A 6, and the test chamber B 8 reach the ultimate vacuum degree of 1.5×10 ^-6 Pa;

Step 4, after the quadrupole mass spectrometer 9, the capacitance film vacuum gauge 2, and the magnetic suspension rotor vacuum gauge 5 are stable for 25 hours, the third vacuum valve 13 and the fourth vacuum valve 16 are closed, and the capacitance film vacuum gauge 2 and the magnetic suspension rotor vacuum gauge 5 are zeroed and residual damping is deducted respectively;

Step 5, open the second vacuum valve 11, adjust the first fine-tuning vacuum valve 1, fill the gas chamber 3 with helium from the helium bottle 10, adjust the inlet pressure according to the test requirements, and record the corresponding reading of the capacitance film vacuum gauge 2 as 1.03×10 ⁵ Pa;

Step 6, record the initial indication of the magnetic suspension rotor vacuum gauge 5 p _SRG0 =4.3461×10 ^-5 Pa, the initial value of the helium partial pressure ion flow I ₀ =1.5538×10 ^-13 A of the quadrupole mass spectrometer 9, adjust the second fine-tuning vacuum valve 4 until the indication of the magnetic suspension rotor vacuum gauge 5 p _SRG =2.7998×10 ^-2 Pa, the indication of the helium partial pressure ion flow I of the quadrupole mass spectrometer 9 =5.9425×10 ^-5 A, and record the indications of the magnetic suspension rotor vacuum gauge 5 and the quadrupole mass spectrometer 9 at the same time;

Step 7, calculating the helium sensitivity of the quadrupole mass spectrometer 9 according to the data measured in step 6. In the embodiment of the present application, the helium sensitivity of the quadrupole mass spectrometer 9 is calculated according to formula ① to obtain S _He =2.13×10 ^-3 A/Pa;

Step 8, open the fourth vacuum valve 16, and re-evacuate the test chamber A 6 and the test chamber B 8 to the ultimate vacuum degree of 1.6×10 ^-6 Pa;

Step 9, close the first vacuum valve 7 and the fourth vacuum valve 16, and record the change in the ion flow of the quadrupole mass spectrometer 9 within 180 minutes. =9.1283×10 ^-12 A;

Step 10, open the first vacuum valve 7, and repeat step 8;

Step 11, close the fourth vacuum valve 16, record the initial ion current value I _i =1.7133×10 ^-13 A of the quadrupole mass spectrometer 9, and after 180 minutes, record the value of the ion current of the quadrupole mass spectrometer 9 after the increase caused by the helium penetration of the measured glass material I _f =1.9142×10 ^-10 A;

Step 12, calculating the permeability of the glass material 15 to be tested. Specifically, according to formula ②, it is calculated that K=1.19×10 ^-15 cm ² /s.

The formula in the above embodiment is as follows:

①

In formula ①: is the pressure indication of the magnetic suspension rotor vacuum gauge 5, in Pa;/> is the initial pressure indication of the magnetic suspension rotor vacuum gauge 5, in Pa;/> is the initial helium ion current of the quadrupole mass spectrometer 9, in A;/> is the helium ion flow of the quadrupole mass spectrometer 9, in A;

②

In formula ②: is the value of the ion current after it increases in step 11, in units of A;/> is the initial ion current value in step 11, in A;/> is the change in the test chamber B 8 in step 9 over a period of time, in units of A; /> is the volume of test chamber B 8, in m ³ ; /> is the thickness of the glass material 15 to be measured, in m; /> is a period of time in step 9, in units of s; A is the area of the glass material 15 to be tested, in units of m ² ; /> is the pressure of helium in the gas-filled chamber 3, in Pa.

In the embodiment of the present application, since the gas sensitivity of the quadrupole mass spectrometer 9 is affected by the type of gas, the sensitivity may be different for different gases. Therefore, the embodiment of the present application performs an online calibration of the helium sensitivity in step 7, thereby reducing the experimental error and ensuring the accuracy of the measurement result. In addition, in step 9, the embodiment of the present application uses the quadrupole mass spectrometer 9 to measure the helium permeability of the test chamber B 8 in a no-load state, and utilizes the characteristics that the test chamber A 6 and the test chamber B 8 have the same volume and the same material. When calculating the permeability of the measured glass material 15, the helium permeability of the two test chambers themselves is subtracted, thereby eliminating the influence of the helium attached to the test chamber itself on the experimental results and ensuring the accuracy of the measurement result.

The serial numbers of the embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

The above disclosure is only the preferred embodiment of the present application, which certainly cannot be used to limit the scope of rights of the present application. Therefore, equivalent changes made according to the claims of the present application are still within the scope covered by the present application.

Claims (7)

1. A glass material helium permeability testing device for quantum vacuum measurement standard, which is characterized by comprising: the device comprises a first fine tuning vacuum valve, a capacitance film vacuum gauge, a plenum chamber, a second fine tuning vacuum valve, a magnetic suspension rotor vacuum gauge, a test chamber A, a first vacuum valve, a test chamber B, a quadrupole mass spectrometer, a helium bottle, a second vacuum valve, a first vacuum air extractor group, a third vacuum valve, a glass material to be tested, a fourth vacuum valve, a KF interface and a second vacuum air extractor group, wherein:

the helium bottle is connected with the plenum chamber, and the second vacuum valve and the first fine-tuning vacuum valve are sequentially arranged on a connected pipeline;

The plenum chamber is connected with the capacitance film vacuum gauge and the first vacuum air extractor group, and the pipeline connected with the first vacuum air extractor group is provided with the third vacuum valve;

The plenum chamber is connected with the test chamber A, a second fine-tuning vacuum valve is arranged on one connected pipeline, and the KF interface and the glass material to be tested are arranged on the other connected pipeline;

the test chamber A is connected with the magnetic suspension rotor vacuum gauge;

The test chamber A is connected with the test chamber B, and the first vacuum valve is arranged on a connected pipeline;

the testing chamber B is connected with the quadrupole mass spectrometer and the second vacuum air extractor group, and a pipeline connected with the second vacuum air extractor group is provided with the fourth vacuum valve;

the volume of the test chamber A is the same as that of the test chamber B, and the materials are the same.

2. The device for testing helium permeability of glass materials for quantum vacuum measurement standards according to claim 1, wherein the glass materials to be tested are in a round sheet shape, the diameter range is 30 mm-40 mm, and the thickness range is 2 mm-3 mm.

3. The device for testing helium permeability of glass materials for quantum vacuum measurement standards according to claim 1, wherein the minimum detectable partial pressure of the quadrupole mass spectrometer is 1 x 10 ^-10 Pa or less.

4. The device for testing helium permeability of glass materials for quantum vacuum measurement standards according to claim 1, wherein the accuracy of measurement of the capacitance film vacuum gauge is within +/-0.15%.

5. The device for testing helium permeability of glass materials for quantum vacuum measurement standards according to claim 1, wherein the stability of the magnetic suspension rotor vacuum gauge is less than or equal to 1%/year.

6. A method for testing helium permeability of glass material for quantum vacuum measurement standard, characterized in that the device for testing helium permeability of glass material for quantum vacuum measurement standard according to any one of claims 1 to 5 comprises:

Step 1, fixing the tested glass material on the KF interface;

Step 2, starting the first vacuum air extractor group and the second vacuum air extractor group, opening the first vacuum valve, the third vacuum valve and the fourth vacuum valve, exhausting the plenum chamber, the test chamber A, the test chamber B and the connecting pipeline, opening the capacitance film vacuum gauge connected with the plenum chamber and the magnetic suspension rotor vacuum gauge connected with the test chamber A, and opening the quadrupole mass spectrometer when the pressure in the test chamber A and the test chamber B is lower than 10 ^-2 Pa;

Step 3, continuously pumping air to enable the plenum chamber, the test chamber A and the test chamber B to reach the ultimate vacuum degree;

Step 4, after the quadrupole mass spectrometer, the capacitance film vacuum gauge and the magnetic suspension rotor vacuum gauge are stabilized for more than 24 hours, closing the third vacuum valve and the fourth vacuum valve, and respectively carrying out zeroing and residual damping deducting operations on the capacitance film vacuum gauge and the magnetic suspension rotor vacuum gauge;

Step 5, opening the second vacuum valve, adjusting the first fine-tuning vacuum valve, filling helium into the inflating chamber from the helium bottle, adjusting the air inlet pressure according to the test requirement, and recording the indication value of the corresponding capacitance film vacuum gauge;

Step 6, recording initial indication values of the magnetic suspension rotor vacuum gauge and initial values of helium partial pressure ion flows of the quadrupole mass spectrometer, adjusting the second fine tuning vacuum valve until the indication values of the magnetic suspension rotor vacuum gauge reach the magnitude of 10 ^-2 Pa, and recording the indication values of the magnetic suspension rotor vacuum gauge and the quadrupole mass spectrometer at the moment;

Step 7, calculating helium sensitivity of the quadrupole mass spectrometer according to the data measured in the step 6;

step 8, opening the fourth vacuum valve, and re-pumping the test chamber A and the test chamber B to the ultimate vacuum degree;

Step 9, closing the first vacuum valve and the fourth vacuum valve, and recording the variation of the ion flow of the quadrupole mass spectrometer within 5-180 min;

step 10, opening the first vacuum valve, and repeating the step 8;

Step 11, closing the fourth vacuum valve, recording the initial ion current value of the quadrupole mass spectrometer, and recording the value of the ion current rise of the quadrupole mass spectrometer caused by helium permeation of the glass material to be tested after the time used in the step 9;

And step 12, calculating the permeability of the tested glass material.

7. The method for testing helium permeability of glass materials for quantum vacuum measurement standards according to claim 6, further comprising, before step 2: and carrying out leak detection on the tested glass material and the KF interface to ensure that the leak detection meets the requirements.