Hydrogen extraction system of instrument for measuring hydrogen content in aluminum alloy

Abstract

The invention relates to the technical field of hydrogen measurement sensing, in particular to a hydrogen extraction system of an instrument for measuring the hydrogen content in aluminum alloy, which is based on the test characteristics of the hydrogen content in the aluminum alloy and combines the test defects in practical application. Infrared light is focused on a sample in a high-temperature-resistant quartz sample tube for multiple times through a mirror surface gold-plated curved surface on the inner wall of the furnace body to fully melt the sample, external temperature control software is matched to accurately control the temperature of a gold-plated infrared focusing heating tube, and negative pressure gas circuit design and circulating water cooling control are combined, so that accurate, rapid and stable heating and test data acquisition are realized; the requirement for large sample detection is met, multiple effects of energy conservation and environmental protection are integrated, and the comprehensive effects of high efficiency, accuracy, reliability, safety and the like are achieved for detection of the hydrogen content in the aluminum alloy.

Description

Technical Field

[0001] This invention relates to the field of hydrogen sensing technology, specifically a hydrogen extraction system for an instrument used to determine the hydrogen content in aluminum alloys. Background Technology

[0002] Aluminum alloys, with their excellent thermal conductivity and formability, have become a core material for lightweighting in the automotive, aerospace, and shipbuilding industries. However, during the manufacturing and processing process, hydrogen readily infiltrates the aluminum alloy matrix and interacts with the matrix's microstructure, such as dislocations, grain boundaries, and secondary particles, inducing defects such as porosity and looseness. This leads to a decline in mechanical properties and severely restricts the reliability of the alloy in service. Therefore, precise monitoring of the hydrogen content in aluminum alloys is essential for industrial applications.

[0003] Because the release conditions of hydrogen in aluminum alloys are very demanding, specific conditions need to be met to quickly and accurately measure its content: First, the solid aluminum alloy needs to be placed in an inert gas atmosphere, heated to near its melting point, and maintained at a constant temperature, placing the aluminum alloy in a critical state between melting and non-melting. If the temperature exceeds the melting point, hydrogen atoms will dissolve again in the melt and be adsorbed, unable to be carried by the carrier gas to the detector for detection. Figure 1 , Figure 2 As shown, when the aluminum alloy used in the experiment was heated to 670°C, the number of hydrogen atoms redissolved in the melt increased exponentially, making it impossible to accurately measure its content. When it cooled and solidified, the hydrogen solubility dropped sharply, so the hydrogen did not have time to escape and form pores.

[0004] Secondly, since the hydrogen content in aluminum alloys is extremely low—typically less than 0.3 micrograms per gram in high-strength aluminum alloys used in aerospace—there are two effective measures to improve the measurement accuracy of such ultra-low hydrogen content: First, increase the sample size to increase the absolute amount of hydrogen during the analysis process, thereby increasing the detector's signal response value and improving the signal-to-noise ratio. Increasing the sample weight can also effectively reduce hydrogen loss during sample preparation and surface adsorption blanks, thus improving measurement accuracy. Second, improve the temperature control accuracy of the hydrogen extraction furnace to ensure rapid hydrogen overflow and prevent dissolution during the extraction and analysis process, thereby improving measurement accuracy.

[0005] Besides this, the current main technology for detecting hydrogen in aluminum alloys is the pulsed inert gas melting method. This involves placing the sample in a graphite crucible, introducing a high-purity inert carrier gas, and then using a high-pressure pulsed arc to melt the sample at high temperature, releasing hydrogen gas. The carrier gas then carries the mixed gas through a purification process to remove impurities before being sent to the detector. The hydrogen content is then calculated using a calibration curve. However, this method also has some significant drawbacks: Firstly, the pulse method uses controlled heating power to achieve temperature control. According to the working principle of a pulse furnace, the total input energy is controlled by adjusting the pulse width and frequency, ultimately stabilizing the sample temperature within the target range. However, it is not a constant temperature. Thus, even with stable power, the surface temperature of the heated sample may not remain constant. This makes it difficult to maintain the aluminum alloy in a molten or non-molten state. Once the sample melts, some hydrogen dissolves in the molten aluminum alloy, leading to lower test results. Furthermore, if the previously tested sample is repeated, secondary hydrogen release occurs, resulting in a hydrogen integral peak in the test results. The hydrogen release result may be much greater than zero, leading to inaccurate and erroneous test results.

[0006] Secondly, because the pulse furnace uses a positive pressure gas path, the sample must be placed into the sample channel before testing. This is because the positive pressure gas path needs to be kept strictly sealed. If the sample is placed during instrument operation, air will intrude due to the pressure difference between the gas path and the outside environment, which will affect the detection accuracy and may contaminate the gas path components. The pressure difference generated by the material falling will cause gas path vibration. To avoid vibration, the sample channel must be designed to be very small. Due to the limitation of the small channel, the maximum diameter of the sample is usually ≤8mm, and the maximum weight is only 5-6g, which cannot meet the testing of large samples. This leads to the difficulty of sample preparation due to the small sample size and the increased impact of signal noise on the analytical results, or even lower than the hydrogen level, thus making it impossible to obtain stable results.

[0007] Based on the above reasons, this invention designs a hydrogen extraction system for an instrument used to determine the hydrogen content in aluminum alloys. Based on the testing characteristics of hydrogen content in aluminum alloys and combined with the testing defects in practical applications, the system achieves accurate, rapid, and stable heating and test data acquisition through the combination of high-precision temperature control and negative pressure gas path design. It also meets the needs of large sample testing, thus playing a comprehensive role in the efficient, accurate, reliable, and safe detection of hydrogen content in aluminum alloys. Summary of the Invention

[0008] The purpose of this invention is to overcome the shortcomings of the prior art and provide a hydrogen extraction system for instruments used to determine the hydrogen content in aluminum alloys. Based on the testing characteristics of hydrogen content in aluminum alloys and combined with the testing defects in practical applications, the system achieves accurate, rapid, and stable heating and test data acquisition through the combination of high-precision temperature control and negative pressure gas path design. It also meets the needs of large sample testing, thus playing a comprehensive role in the efficient, accurate, reliable, and safe detection of hydrogen content in aluminum alloys.

[0009] This invention provides a hydrogen extraction system for an instrument used to determine the hydrogen content in aluminum alloys. The system includes an analytical gas outlet connector, a precision support frame, and a micro-controlled lifting cylinder. A fully mirror-reflective furnace chamber, consisting of a mirror-plated gold-plated infrared reflective focusing heating furnace and high-reflectivity gold-plated retaining heat-protecting plates at its upper and lower ends, is fixedly mounted in the center of the precision support frame. A transparent, high-temperature resistant quartz sample tube is non-contactly installed inside the mirror-plated gold-plated infrared reflective focusing heating furnace. The upper end of the high-temperature resistant quartz sample tube is connected to the furnace head via an O-ring seal to achieve an airtight seal. An analytical gas outlet connector and a water-cooled condenser are respectively installed at the upper end and outer side of the furnace head. The water-cooled condenser is tightly fitted to the outer wall of the furnace head and has an internal water pipe connected to an external cooling water circulator for circulating cooling. A gold-plated infrared focusing heating tube is non-contactly installed around the outside of the high-temperature resistant quartz sample tube. A temperature detector extending into the fully mirror-reflective furnace chamber is located in the middle of the gold-plated infrared reflective focusing heating furnace. A dual-gas-path isolation inlet connector is fixed in the middle of the precision support frame and below the fully mirror-reflective furnace chamber. The upper end of the dual-gas-path isolation inlet connector is sealed to the lower end of the high-temperature quartz sample tube through an O-ring to ensure gas path integrity. The dual-gas-path isolation inlet connector has two independent gas path connectors that are oppositely inlet and connected to the high-temperature quartz sample tube. One of the independent gas path connectors is a carrier gas inlet, and the other is used for gas isolation protection to prevent air from entering. A quartz isolation window is located below the bottom of the high-temperature quartz sample tube. A micro-controlled lifting cylinder is located at the bottom of the precision support frame. A high-temperature resistant cooling fan is located in the lower space of the precision support frame to cool the micro-controlled lifting cylinder and the sample basket.

[0010] The number of gold-plated infrared focusing heating tubes is four, and they are set up without contact with the mirror-plated gold-plated infrared reflection focusing heating furnace.

[0011] The gold-plated infrared focusing heating tube is designed with a directional reflection angle of 54 degrees.

[0012] The temperature detectors are set up in a non-contact manner with the mirror-plated gold infrared reflection focusing heating furnace, the high-temperature resistant quartz sample tube, and the gold-plated infrared focusing heating tube.

[0013] The quartz isolation window is driven by a cylinder located below the isolation plate in the middle of the precision support frame to open and close the sample channel at the bottom of the high-temperature resistant quartz sample tube.

[0014] The quartz isolation window drive cylinder is equipped with a diffuse reflection photoelectric sensor that monitors the opening and closing status of the quartz isolation window to determine whether the micro-controlled lifting cylinder is open or not.

[0015] The analytical gas outlet connector and the furnace head are independent modules that are sealed together by heat-insulating gaskets. The outlet of the analytical gas outlet connector is wrapped with a constant temperature tracing cable and is precisely kept at 60°C by software for constant temperature gas delivery. The analytical gas outlet connector is connected to a high-sensitivity detector and then to an external vacuum pump to create a negative pressure environment inside the high-temperature resistant quartz sample tube.

[0016] The lower end of the furnace head is equipped with a metal sintering dust filter, and the inside of the furnace head is equipped with a 3mm vent hole for gas circulation.

[0017] The sample basket is mounted on the shaft of the micro-controlled lifting cylinder.

[0018] The mirror-plated gold infrared reflective focusing heating furnace has an internal integrated cooling circulating water pipeline. The pipeline is equipped with a quantitative water inlet and a quantitative water outlet for the circulating system, which are connected to an external cooling water circulating machine.

[0019] Compared with the prior art, the present invention has the following beneficial effects: This invention utilizes the precise temperature control capabilities of a gold-plated infrared focusing heating tube, combined with a 54-degree directional reflection angle design. This allows infrared light to be repeatedly focused onto the sample inside the high-temperature resistant quartz sample tube via the gold-plated curved mirror surface of the furnace inner wall, ensuring complete melting. The invention, in conjunction with external temperature control software, employs a PID closed-loop control method to achieve precise temperature regulation of the gold-plated infrared focusing heating tube. This enables instantaneous heating to the set temperature, with a temperature control error controlled within ±1℃. This effectively maintains the stable temperature conditions required for hydrogen extraction, thus solving the technical problem in existing pulse furnaces where temperature control is inherently unstable, making it difficult to maintain the aluminum alloy sample in a molten or non-molten state, thereby affecting the accurate measurement of hydrogen content. Precise temperature control improves the stability of sample melting and hydrogen release rate, effectively enhancing hydrogen analysis accuracy. The heating is rapid and efficient (over 1000℃ in 1 minute), and testing can be performed immediately upon startup without preheating.

[0020] This invention utilizes a vacuum pump connected to the end of the gas path of the device to extract gas from the high-temperature quartz sample tube. By using a vacuum pump with a flow rate slightly greater than the inert gas injection flow rate, a pressure difference is generated to create a negative pressure environment. This prevents significant pressure differences when the sample is introduced, thus avoiding gas path vibration. This solves the problem in the prior art where pulse furnaces, in order to avoid gas path vibration caused by a positive pressure environment, have a smaller sample channel design, resulting in a correspondingly smaller sample size. Furthermore, it avoids the drawbacks of small sample size leading to sample preparation difficulties and increased signal noise affecting the analytical results, or the inability to obtain stable results due to hydrogen at lower measurement levels.

[0021] Compared with pulse furnaces which widely use positive pressure gas paths, the present invention uses a gas seal for carrier gas entry and extracts gas at the end of the analytical gas flow to ensure that no air enters or carrier gas leaks when the furnace is opened, and the airflow is stable during sample injection, thus better ensuring the stability of the analysis.

[0022] The maximum sample size of this invention can reach 20g, which is 5 times larger than that of a pulse furnace, further expanding the detection range and making it applicable to the detection of various metal raw materials, thus broadening its application scenarios. The software temperature control can also further realize multiple modes such as stepped, linear, and isothermal, providing key technical support for studying the degree of hydrogen release at different temperatures. Moreover, the software can achieve fully automated control from sample delivery to detection, eliminating potential differences and deviations caused by human operation and ensuring operational consistency.

[0023] The mirror-plated gold infrared reflective focusing heating furnace of the present invention also integrates a cooling circulating water pipe. Through water circulation, it achieves efficient heat dissipation to protect the furnace body, prevent personnel from being scalded, accelerates cooling and thus shortens the shutdown time. In addition, the waste heat can be recovered for heating and cold water can be recycled, achieving the integrated effect of energy saving and environmental protection.

[0024] The test results of this invention and the existing pulse furnace heating inert gas melting method are compared as follows: Aluminum alloys were tested using the pulse furnace heating inert gas melting method (hereinafter referred to as the pulse method). Data source: *Physical and Chemical Testing - Chemical Section*, 2025, Vol. 3. The test results are as follows: Figure 7 As shown in the figure: When using the pulse method to determine the hydrogen content in aluminum and aluminum alloys, the working principle of the pulse method determines that it is not applicable to the determination of hydrogen in aluminum and aluminum alloys. After the sample is heated, the hydrogen cannot be completely extracted. Therefore, the measurement data of the first test does not represent the full true content in the sample. After waiting for the sample to cool down and then heating it for a second analysis, there is still a significant amount of hydrogen released.

[0025] When the hydrogen extraction system of the present invention is equipped with a detection system, the test data are as follows: Figure 4 As shown, the following can be seen: First, the test results of each sample in the test data table show that hydrogen can be completely released in the first test, and there is basically no hydrogen left in the second test.

[0026] Secondly, the analysis of the signal spectrum also proves that the peak shape was clear and obvious in the first analysis, while the second analysis showed a blank baseline for the signal.

[0027] To further illustrate, this invention effectively solves the shortcomings of incomplete hydrogen extraction in the pulse method of the prior art, and can be effectively and widely used for accurate determination of aluminum and aluminum alloys. Attached Figure Description

[0028] Figure 1 This is a schematic diagram illustrating the change in hydrogen solubility with temperature as mentioned in the background section of this invention.

[0029] Figure 2 This is a schematic diagram comparing the solubility of hydrogen in solid and molten aluminum alloys, as mentioned in the background section of this invention.

[0030] Figure 3 This is a cross-sectional schematic diagram of the system of the present invention.

[0031] Figure 4 This is a schematic diagram of the test data results of the system of the present invention.

[0032] Figure 5 This is a schematic diagram showing the relationship between the reflection angle and the emission angle of the gold-plated infrared focusing heating tube of the present invention.

[0033] Figure 6 This is a schematic diagram of the axial direction of the system of the present invention.

[0034] Figure 7 This is a schematic diagram illustrating the results of the pulse method for testing hydrogen content in the prior art, which is beneficial to the present invention.

[0035] Explanation of reference numerals in the attached figures: 1: Analytical gas outlet connector; 2: Water-cooled condenser; 3: Furnace head; 4: Furnace head O-ring seal; 5: Metal sintered dust filter; 6: Precision load-bearing fixing frame; 7: Temperature detector; 8: Mirror-plated gold-plated infrared reflective focusing heating furnace; 9: High-temperature resistant quartz sample tube; 10: Dual-path isolation gas inlet connector seat; 11: Quartz isolation window; 12: High-temperature resistant cooling fan; 13: Micro-controlled lifting cylinder; 14: Circulation system quantitative water outlet; 15: Gold-plated infrared focusing heating tube; 16: High-reflectivity gold-plated fixed temperature protection plate; 17: Circulation system quantitative water inlet; 18: O-ring seal; 19: Quartz isolation window drive cylinder; 20: Diffuse reflection photoelectric sensor; 21: Sample basket. Detailed Implementation

[0036] The present invention will now be further described with reference to the accompanying drawings: See Figures 1-7 This invention provides a hydrogen extraction system for an instrument used to determine the hydrogen content in aluminum alloys: The system includes an analytical gas outlet connector 1, a precision support and fixing frame 6, and a micro-controlled lifting cylinder 13. The precision support and fixing frame 6 has a centrally fixed, fully mirror-reflective furnace chamber consisting of a mirror-plated gold-plated infrared reflective focusing heating furnace 8 and high-reflectivity gold-plated fixed-position heat-protecting plates 16 at its upper and lower ends. Inside the mirror-plated gold-plated infrared reflective focusing heating furnace 8, a transparent high-temperature resistant quartz sample tube 9 is non-contactly installed. The upper end of the high-temperature resistant quartz sample tube 9 is connected to the furnace head 3 via a furnace head O-ring seal 4 to achieve a gas seal. The upper end and outer side of the furnace head 3 are respectively equipped with an analytical gas outlet connector 1 and a water-cooled condenser 2. The water-cooled condenser 2 is tightly fitted to the outer wall of the furnace head 3. The water-cooled condenser 2 has an internal water flow pipe and is externally connected to a cooling water circulator for circulating cooling. A gold-plated infrared focusing heating tube 15 is non-contactly installed around the outside of the high-temperature resistant quartz sample tube 9. The central part of the mirror-plated gold-plated infrared reflective focusing heating furnace 8... A temperature detector 7 is installed in the position of the fully mirror-reflective furnace. A dual-gas-path isolation inlet connector 10 is fixed in the middle of the precision support frame 6 and below the fully mirror-reflective furnace. The upper end of the dual-gas-path isolation inlet connector 10 is sealed to the lower end of the high-temperature quartz sample tube 9 through an O-ring 18 to ensure gas path integrity. The dual-gas-path isolation inlet connector 10 is provided with two independent gas path connectors that are oppositely inlet and connected to the high-temperature quartz sample tube 9. One of the independent gas path connectors is a carrier gas inlet, and the other is used for gas isolation protection to prevent air from entering. A quartz isolation window 11 is provided below the bottom of the high-temperature quartz sample tube 9. A micro-controlled lifting cylinder 13 is provided at the bottom of the precision support frame 6. A high-temperature resistant cooling fan 12 is provided in the lower space of the precision support frame 6 to cool the micro-controlled lifting cylinder 13 and the sample basket 21.

[0037] There are four gold-plated infrared focusing heating tubes 15, and they are set up without contact with the mirror-plated gold infrared reflection focusing heating furnace 8.

[0038] See Figure 5 The gold-plated infrared focusing heating tube 15 is designed with a directional reflection angle of 54 degrees. Because the gold-plated infrared focusing heating tube 15 is cylindrical with a 360-degree circular cross-section, a 306-degree area around its circumference is covered with a gold plating layer, leaving the remaining 54 degrees exposed. This forms a structure of "gold-plated reflective area + exposed emission area". During operation, the gold-plated infrared focusing heating tube 15 radiates infrared light throughout. The 306-degree gold-plated area reflects the reflected infrared light through a mirror, converging it and directionally emitting it from the 54-degree exposed area to the sample area, achieving rapid temperature increase.

[0039] Temperature detector 7 is set in a non-contact manner with mirror-plated gold infrared reflection focusing heating furnace 8, high-temperature resistant quartz sample tube 9 and gold-plated infrared focusing heating tube 15.

[0040] The quartz isolation window 11 opens and closes the sample channel at the bottom of the high-temperature resistant quartz sample tube 9 under the drive of the quartz isolation window drive cylinder 19, which is located below the isolation plate in the middle of the precision bearing fixing frame 6.

[0041] A diffuse reflection photoelectric sensor 20 is installed on the quartz isolation window drive cylinder 19 to monitor the opening and closing status of the quartz isolation window 11 and to determine whether the micro-controlled lifting cylinder 13 is open or closed.

[0042] The analytical gas outlet connector 1 and the furnace head 3 are independent modules connected by a heat-insulating gasket to avoid direct heat transfer. The outlet of the analytical gas outlet connector 1 is wrapped with a constant-temperature tracing cable and precisely maintained at 60°C by software to match the constant-temperature operation requirements of the external detector, ensuring constant-temperature gas delivery and stable gas path operation. After connecting to a high-sensitivity detector, the analytical gas outlet connector 1 is connected to an external vacuum pump to create a negative pressure environment inside the high-temperature resistant quartz sample tube 9.

[0043] The lower end of the furnace head 3 is securely fitted with a metal sintered dust filter 5 via threads. The filter is filled with a removable and replaceable 3A molecular sieve to achieve dual purification functions. The metal sintered dust filter 5 intercepts the dust generated by the sample reaction, while the 3A molecular sieve simultaneously adsorbs moisture and impurities in the sample, effectively improving the purity of the subsequent gas.

[0044] The burner head 3 has a 3mm vent hole inside for gas circulation.

[0045] The sample basket 21 is mounted on the shaft of the micro-controlled lifting cylinder 13.

[0046] The mirror-plated gold infrared reflective focusing heating furnace 8 has an internal integrated cooling circulating water pipe, which is equipped with a circulating system quantitative water inlet 17 and a circulating system quantitative water outlet 14 that are connected to an external cooling water circulating machine.

[0047] Working principle: Before analysis, the sample basket 21 is in standby mode at the bottom of the precision support frame 6. After the analysis is started, the sample basket 21 is precisely raised to the inside of the high-temperature resistant quartz sample tube 9 and located in the heating area in the middle of the mirror-plated gold infrared reflection focusing furnace 8 by the micro-controlled lifting cylinder 13, thus completing the sample transfer.

[0048] Before starting the test, the host computer software must be opened first. Then, high-purity nitrogen gas is continuously introduced into the dual-gas-path isolation inlet connector 10 to pre-build an inert protective atmosphere inside the high-temperature resistant quartz sample tube 9. At the same time, the vacuum pump connected to the analytical gas outlet connector 1 is started, and the vacuum pump flow rate is slightly greater than the inert gas injection flow rate to create a pressure difference and form a negative pressure. After the preparation is completed, the quartz cup containing the sample to be tested is placed into the sample basket 21, and the test process can be started by clicking "Start Analysis".

[0049] After startup, the gold-plated infrared focusing heating tube 15 emits infrared light inside the furnace. The infrared light is divided into two parts: one part directly irradiates the sample surface, and the other part penetrates the quartz tube and is projected onto the inner wall of the mirror-plated gold-plated infrared reflection focusing heating furnace 8. Through the synergistic reflection of the gold-plated curved mirror on the inner wall of the mirror-plated gold-plated infrared reflection focusing heating furnace 8 and the gold-plated mirror on the inner wall of the high-reflection gold-plated fixed temperature protection plate 16, the infrared light is focused on the central area of ​​the high-temperature resistant quartz sample tube 9. The coordinated operation of the gold-plated infrared focusing heating tube 15 and the mirror-plated gold-plated infrared reflection focusing heating furnace 8 forms an energy closed loop of "emission-reflection-focusing". After multiple reflections by the inner wall, the light is focused onto the sample surface inside the tube, improving heating efficiency and focusing accuracy. At the same time, the quantitative water inlet 17 and the quantitative water outlet 14 of the circulation system of the mirror-plated gold-plated infrared reflection focusing heating furnace 8 are connected to an external cooling water circulator to achieve temperature control assistance and ensure the stability of the heating process. Once the temperature detector 7 detects that the temperature inside the furnace has reached the set target and stabilized, the program triggers the quartz isolation window drive cylinder 19 to open the sample tube channel through the quartz isolation window 11. After the diffuse reflection photoelectric sensor 20 detects that the quartz isolation window 11 is fully open, the micro-controlled lifting cylinder 13 is immediately activated to drive the sample basket 21 to accurately deliver the aluminum alloy sample to the center of the furnace heating area inside the high-temperature resistant quartz sample tube 9. During this process, the high-temperature resistant cooling fan 12 runs continuously to cool the shaft of the micro-controlled lifting cylinder 13 and the sample basket 21 after the test is completed. Under the protection of inert gas, the sample undergoes high-temperature thermal extraction, causing hydrogen to escape and generate hydrogen gas.

[0050] The generated hydrogen gas first flows through a metal sintered dust filter 5 with a built-in 3A molecular sieve to remove dust impurities and moisture entrained in the gas. It then enters the furnace head 3. Because the outer wall of the furnace head 3 is tightly attached to a water-cooled condenser 2, the condenser 2, through its internal circulating water pipes, can quickly conduct and remove heat from the high-temperature gas in the furnace head 3 and its internal vents. This heat exchange within the furnace head 3 achieves precise cooling of the internal circulating gas (constant temperature 25-30 degrees Celsius, with the cooling water circulator set between 25-30 degrees Celsius). The overflowing hydrogen gas undergoes cooling here. The cooled hydrogen gas is then sent to a high-sensitivity detector through the analytical gas outlet connector 1. Finally, the detector detects the hydrogen content and thermal desorption rate, and outputs calculated data.

[0051] In the description of this invention, it should be noted that the terms "upper", "lower", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0052] This invention comprehensively addresses several technical shortcomings encountered in existing technologies for detecting hydrogen content in aluminum alloys using pulse furnaces, such as unstable temperature control, poor detection accuracy, and small sample volume. The invention innovatively employs a special gold-plated coating combined with a 54° directional reflection angle design, optimizing the directional emission structure and constructing a "emission-reflection-focusing" energy closed loop with the furnace mirror reflection system. This precisely solves the pain points of low emission efficiency and slow heating in traditional heating tubes, maximizing heating power utilization, achieving faster heating rates and higher temperature control accuracy (precisely avoiding temperature breaches of the aluminum alloy melting point), accelerating temperature adjustment response speed, significantly shortening the analysis cycle, and simultaneously offering energy-saving and consumption-reducing advantages. The invention's dual-gas-path isolation inlet connector features two independent opposing gas paths, serving as a carrier gas inlet and an air isolation protection port, respectively. A high-purity inert atmosphere is pre-constructed within the quartz sample tube, preventing hydrogen oxidation or impurity interference caused by air entry from the source. This solves the problem of easy air mixing in traditional single-gas-path systems, ensuring the accuracy of hydrogen element detection. This invention integrates a multi-layered purification and temperature control design in its gas path process: a metal sintered dust filter with a built-in 3A molecular sieve simultaneously filters out dust impurities and moisture; a water-cooled condenser rapidly reduces the temperature of the high-temperature reaction gas; and a constant-temperature heating cable is wrapped around the analytical gas outlet connector to ensure constant-temperature hydrogen delivery to the detector. The entire process avoids the impact of moisture condensation, impurity residue, or temperature fluctuations in the gas path on the detection results, improving the efficiency and reliability of gas path pretreatment. This invention uses a quartz isolation window to drive a cylinder in conjunction with a diffuse reflection photoelectric sensor. The sensor monitors the window's opening and closing status in real time, allowing the micro-controlled lifting cylinder to activate only when the window is fully open, avoiding conflicts between sample delivery and window movement. The lifting cylinder drives the sample basket to precisely lift and lower to the center of the furnace, achieving an automated closed loop of "action-detection-feedback," improving the accuracy and safety of sample delivery. The high-temperature resistant cooling fan is specifically fixed to the lower part of the frame for cooling the lifting cylinder shaft and sample basket, preventing the cooling airflow from interfering with the furnace temperature field and effectively extending the service life of moving parts, solving the problem of easy aging of transmission components under high-temperature environments.

[0053] Based on various technical challenges encountered in actual testing processes, this invention provides targeted solutions and integrates them in a reasonable manner. It overcomes the limitations and shortcomings of traditional pulse furnace methods, offering an effective solution for rapid, stable, and accurate hydrogen content detection. Furthermore, its reasonable structural design, convenient operation, and high flexibility allow for its extension to other metal detection processes. It possesses strong problem-solving capabilities and expansion potential in this field, providing an important and feasible solution for hydrogen content detection. The overall results exceed expectations, demonstrating significant market application value.

Claims

1. A hydrogen extraction system for an instrument used to determine the hydrogen content in aluminum alloys, comprising an analytical gas outlet connector (1), a precision support and fixing frame (6), and a micro-controlled lifting cylinder (13), characterized in that, The precision support frame (6) is fixedly equipped with a fully mirror-reflective furnace chamber consisting of a mirror-plated gold-plated infrared reflection focusing heating furnace (8) and high-reflection gold-plated fixed heat-protecting plates (16) at its upper and lower ends. A transparent high-temperature resistant quartz sample tube (9) is non-contactly installed inside the mirror-plated gold-plated infrared reflection focusing heating furnace (8). The upper end of the high-temperature resistant quartz sample tube (9) is connected to the furnace head (3) via a furnace head O-ring seal (4) to achieve an airtight seal. The furnace head (3)... The upper end and the outer side are respectively provided with the analytical gas outlet connector (1) and the water-cooled condenser (2). The water-cooled condenser (2) is closely attached to the outer wall of the furnace head (3). The water-cooled condenser (2) has a built-in water flow pipe and is connected to an external cooling water circulator for circulating cooling. The high-temperature resistant quartz sample tube (9) is surrounded by a gold-plated infrared focusing heating tube (15) without contact. The mirror gold-plated infrared reflection focusing heating furnace (8) is provided with a tube extending into the full mirror reflection furnace chamber at the middle position. The temperature detector (7) is fixed with a dual-gas-path isolation inlet connector seat (10) in the middle of the precision bearing fixed frame (6) and below the full mirror reflection furnace. The upper end of the dual-gas-path isolation inlet connector seat (10) is sealed to the lower end of the high-temperature resistant quartz sample tube (9) through an O-ring seal (18) to achieve gas path integrity. The dual-gas-path isolation inlet connector seat (10) is provided with two independent gas inlets that are opposite to each other and connected to the high-temperature resistant quartz sample tube (9). The gas path connector has one path as a carrier gas inlet and the other path as a gas isolation protection to prevent air from entering. A quartz isolation window (11) is provided below the bottom of the high-temperature resistant quartz sample tube (9). The micro-controlled lifting cylinder (13) is provided at the bottom of the precision support fixing frame (6). A high-temperature resistant cooling fan (12) is provided in the lower space of the precision support fixing frame (6) to cool the micro-controlled lifting cylinder (13) and the sample basket (21).

2. The hydrogen extraction system for an instrument for determining the hydrogen content in aluminum alloys according to claim 1, characterized in that, The number of gold-plated infrared focusing heating tubes (15) is four, and they are set in a non-contact manner with the mirror-plated gold infrared reflection focusing heating furnace (8).

3. The hydrogen extraction system for an instrument for determining the hydrogen content in aluminum alloys according to claim 2, characterized in that, The gold-plated infrared focusing heating tube (15) is designed with a directional reflection angle of 54 degrees.

4. The hydrogen extraction system for an instrument for determining the hydrogen content in aluminum alloys according to claim 1, characterized in that, The temperature detector (7) is set in a non-contact manner with the mirror-plated gold infrared reflection focusing heating furnace (8), the high-temperature resistant quartz sample tube (9), and the gold-plated infrared focusing heating tube (15).

5. The hydrogen extraction system for an instrument for determining the hydrogen content in aluminum alloys according to claim 1, characterized in that, The quartz isolation window (11) opens and closes the sample channel at the bottom of the high-temperature quartz sample tube (9) under the drive of the quartz isolation window drive cylinder (19) located below the isolation plate in the middle of the precision bearing fixing frame (6).

6. The hydrogen extraction system for an instrument for determining the hydrogen content in aluminum alloys according to claim 5, characterized in that, The quartz isolation window drive cylinder (19) is equipped with a diffuse reflection photoelectric sensor (20) for monitoring the opening and closing state of the quartz isolation window (11) and determining whether the micro-controlled lifting cylinder (13) is open or closed.

7. The hydrogen extraction system for an instrument for determining the hydrogen content in aluminum alloys according to claim 1, characterized in that, The analytical gas outlet connector (1) and the furnace head (3) are independent modules that are sealed together by heat insulation gaskets. The outlet of the analytical gas outlet connector (1) is wrapped with a constant temperature tracing cable and is precisely kept at 60°C by software for constant temperature gas delivery. The analytical gas outlet connector (1) is connected to a high-sensitivity detector and then to an external vacuum pump to create a negative pressure environment inside the high-temperature resistant quartz sample tube (9).

8. The hydrogen extraction system for an instrument for determining the hydrogen content in aluminum alloys according to claim 1, characterized in that, The lower end of the furnace head (3) is equipped with a metal sintering dust filter (5), and the furnace head (3) is provided with a 3mm ventilation hole for gas circulation.

9. The hydrogen extraction system for an instrument for determining the hydrogen content in aluminum alloys according to claim 1, characterized in that, The sample basket (21) is mounted on the shaft of the micro-controlled lifting cylinder (13).

10. The hydrogen extraction system for an instrument for determining the hydrogen content in aluminum alloys according to claim 1, characterized in that, The internal integrated cooling circulating water pipe of the mirror-plated gold infrared reflection focusing heating furnace (8) is provided with a circulating system quantitative water inlet (17) and a circulating system quantitative water outlet (14) connected to an external cooling water circulating machine.

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