A multi-class non-ferrous breakdown voltage testing device, system and method

Abstract

This invention relates to the field of electrical performance testing technology, and discloses a device, system, and method for testing the breakdown voltage of various non-ferrous metals. The testing device includes a test chamber with multiple independent slots, a temperature and humidity control system, an electrode module, a power supply module, and a data acquisition module. Through multi-channel synchronous testing, dynamic temperature and liquid level control, symmetrical electrode layout, and high-speed data acquisition, it achieves high-precision breakdown voltage testing of multiple samples under constant environment. The system integrates a central control unit that automatically sets the voltage boost rate based on sample parameters, independently boosts voltage through multiple channels, and synchronously acquires breakdown data. A dual-threshold algorithm is used to determine breakdown events in real time. The method covers the entire process of solution preparation, sample installation, electric field optimization, voltage boost control, and data determination. Compared with existing technologies, this invention improves testing efficiency and measurement accuracy, reduces environmental interference, and is suitable for batch testing and quality control of tantalum, niobium, and their oxide materials.

Description

Technical Field

[0001] This invention belongs to the field of electrical performance testing technology, specifically relating to a high-precision breakdown voltage testing device, system, and method for tantalum, niobium, and their oxide materials. Background Technology

[0002] Tantalum, niobium, and their oxides are widely used in capacitor manufacturing, semiconductor devices, and energy storage due to their excellent dielectric properties and chemical stability. Breakdown voltage, as a key indicator for evaluating the electrical performance and quality stability of materials, directly affects their performance in high-reliability applications. Current technologies for measuring breakdown voltage mainly include DC voltage boosting, AC withstand voltage testing, and pulse breakdown methods, but these methods still suffer from problems such as low testing efficiency, insufficient environmental control, low detection accuracy, and uneven electric field distribution. In particular, the breakdown voltage of tantalum and niobium materials is extremely sensitive to ambient temperature; for every 10°C increase in temperature, the breakdown voltage may decrease by 5% to 8%. Simultaneously, liquid level fluctuations and improper electrode layout can easily lead to uneven electric field strength, thus introducing systematic errors. Therefore, there is an urgent need to develop a breakdown testing system that supports multi-channel synchronous testing, possesses dynamic environmental control and high-speed data acquisition capabilities, and can optimize electric field uniformity to improve measurement accuracy, stability, and testing efficiency, meeting the needs of electrical performance evaluation and quality control of non-ferrous metal materials. Summary of the Invention

[0003] To address the problems of low single-channel testing efficiency, insufficient environmental parameter control, uneven electric field distribution, and low breakdown determination accuracy in existing technologies, this invention provides a novel testing device and method that can significantly improve testing efficiency, measurement accuracy, and testing environment stability, and achieve simultaneous testing and intelligent control of multiple samples.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A multi-type non-ferrous metal breakdown voltage testing device includes a test tank, a temperature and humidity control system, an electrode module, a power supply module, and a data acquisition module, characterized in that:

[0006] The test slot is equipped with multiple independent slots, each slot is used to fix one sample to be tested, and each slot corresponds to a set of electrodes;

[0007] The electrode module includes a cathode plate disposed in each slot and arranged opposite to the sample to be tested, and an adjustable product steel bar for supporting the sample. The cathode plate and the sample form a locally symmetrical electric field distribution. The product steel bar can be adjusted in height by adjusting the positioning screw and the product steel bar support to control the immersion depth of the sample to be tested.

[0008] The temperature and humidity control system includes a circulating inlet pipe, a circulating return pipe, a tilting plate, and a liquid level adjusting screw sleeve. Through circulating flow and liquid level control, the liquid level of the test solution is kept constant and the overflow is uniform.

[0009] The temperature control module includes a temperature-sensing thermocouple and a heating element, and maintains the temperature fluctuation range of the test solution within ±0.5℃ through a temperature controller;

[0010] The data acquisition module includes a voltage sensor and a current sensor with a response speed of microseconds. It synchronously acquires voltage drop and current change data at the moment of breakdown and determines the breakdown event through a threshold comparison algorithm.

[0011] The power module automatically calculates the boost rate based on the input sample parameters and applies voltage independently to each slot in a constant current mode until the sample breaks down.

[0012] The liquid-turning plate is a structural component fixedly installed on the inner wall of the test tank. Its top is equipped with serrated overflow teeth to allow for the natural overflow of the energizing liquid. The liquid level adjusting screw sleeve is located at multiple support points outside the test tank. Rotating the screw sleeve allows for localized raising and lowering of the tank, fine-tuning the overall levelness of the test tank. When the test solution level rises to the top of the liquid-turning plate, the overflow velocity at both ends of the plate is essentially the same, maintaining liquid level balance and ensuring consistent electric field distribution and repeatability of test results. The product steel bar is made of stainless steel and has multiple equally spaced welding points for mounting multiple test samples.

[0013] The temperature control module uses a PID controller to dynamically adjust the power output of the heating element based on the difference between the real-time temperature fed back by the thermocouple and the set temperature, so that the temperature fluctuation of the test solution is controlled within ±0.5℃.

[0014] The data acquisition module also includes a noise filtering circuit, which uses a differential amplifier and a low-pass filter with a cutoff frequency of 10kHz to eliminate high-frequency interference signals.

[0015] In the threshold comparison algorithm, the condition for determining a breakdown event is: within 1ms, the voltage value drops by more than 50% of the current value, and the current value rises to more than 10 times the initial value.

[0016] The water inlet direction of the circulating liquid inlet pipe is arranged perpendicular to the arrangement direction of the slots in the test tank, and each slot is equipped with an independent water supply pipe. The flow rate is adjusted by a stepper motor-driven valve to ensure a constant liquid level.

[0017] The product steel bar is fixed to the top of the test groove. The product steel bar is moved up and down by the threaded adjustment and positioning screw, and the adjustment range is 0 to 15 mm.

[0018] The formula for calculating the boost rate (V) in the power module is as follows:

[0019] v = k·I 密度 ·W 坯块 / S 接触面积

[0020] Where v is the pressure increase rate (V / s), k is the material property coefficient, and I 密度 Preset current density (A / m) 2 ), W 坯块 S represents the weight of the billet (g). 接触面积 The contact area between the electrode and the sample (m²) 2 ).

[0021] The steel bars used in the product are made of stainless steel.

[0022] The top of the liquid-turning plate is provided with serrated overflow teeth, with a tooth height of 1mm and a tooth spacing of 3mm.

[0023] The breakdown event is determined using a dual-threshold strategy: the voltage drops by ≥50% within 1ms and the current increases to more than 10 times the initial value.

[0024] The temperature control module uses a PID controller with a proportional band set between 0.8 and 1.2 and an integral time of 90 to 120 seconds.

[0025] The flow rate of the circulating liquid inlet pipe is controlled at 1.5±0.2L / min, and the valve opening is controlled by a stepper motor.

[0026] The test slot is equipped with 10 to 20 independent card slots for synchronous testing.

[0027] The present invention also provides a multi-channel breakdown voltage testing system, including the above-mentioned testing device and a central control unit, which is used to automatically allocate test channels according to the input sample parameters (including weight, material type and target current density) and generate independent boost rate commands for each channel;

[0028] A multi-channel data acquisition module is connected to the voltage / current sensor of the test device to synchronously acquire the voltage and current signals of each channel, with a sampling frequency of not less than 1MHz;

[0029] The breakdown determination module detects sudden voltage drops and sudden current increases in each channel and determines breakdown based on a threshold comparison algorithm.

[0030] The feedback control module is used to dynamically adjust the flow rate of the liquid level adjusting screw sleeve and the circulating liquid inlet pipe based on the liquid level fluctuation detection results, so as to ensure that the liquid level fluctuation amplitude is ≤ ±0.2mm.

[0031] This invention also provides a method for testing the breakdown voltage of various non-ferrous metals, comprising the following steps:

[0032] (1) Solution preparation and temperature control initialization:

[0033] Prepare a test solution of ethylene glycol and nitric acid, and adjust the conductivity to 1.5–2.5 μS / cm; inject the solution into the test cell, heat it to 30–80℃ using a temperature control module, and maintain the temperature fluctuation ≤ ±0.5℃;

[0034] (2) Sample mounting and electric field adjustment:

[0035] The sample to be tested is welded to the product steel strip. The immersion depth of the sample is controlled by adjusting the positioning screw by 5-10 mm. The liquid level adjusting screw sleeve is adjusted to control the overflow gap of the tipping plate so that the electric field uniformity deviation is ≤5%.

[0036] (3) Parameter self-tuning and boost test:

[0037] Input the sample weight and preset current density. The central control unit calculates the parameters of each channel according to the boost rate formula. The power module applies boost in constant current mode, with a boost rate range of 10 to 200V / s.

[0038] (4) Breakdown event determination and recording:

[0039] The voltage and current signals of each channel are collected synchronously. When the voltage drops by ≥50% and the current rises by ≥10 times within 1ms, a breakdown event is determined to have occurred. The breakdown voltage value is recorded and a test report is generated.

[0040] Compared with the prior art, the present invention has the following significant advantages:

[0041] Significantly improved testing efficiency: Supports simultaneous testing of multiple samples, with overall efficiency 5 to 8 times higher than traditional single-channel devices;

[0042] The testing environment is stable and reliable: temperature fluctuation ≤ ±0.5℃, liquid level fluctuation ≤ ±0.2mm, electric field uniformity deviation ≤ 5%, effectively reducing environmental interference;

[0043] Significantly improved measurement accuracy: Microsecond-level transient signal acquisition and intelligent breakdown determination achieve a breakdown voltage measurement error of ≤±1.5%;

[0044] High degree of intelligent operation: parameter self-tuning and automatic boost control reduce human intervention, making the testing process more efficient and stable;

[0045] Wide range of applications: compatible with block and columnar samples of tantalum, niobium and their oxide materials, suitable for research and development and quality testing scenarios.

[0046] In summary, this invention solves the key pain points of traditional breakdown voltage testing technology through structural innovation, control system optimization, and improved data acquisition accuracy, and has significant application prospects and promotional value. Attached Figure Description

[0047] Figure 1 : Schematic diagram of the test device structure of the present invention (side view).

[0048] Figure 2 : Schematic diagram of the test device structure of the present invention (front view).

[0049] The meanings represented by the labels in the figure are as follows:

[0050] 1—Test tank; 2—Adjusting seat; 3—Product steel bar support; 4—Product steel bar; 5—Sample to be tested; 6—Liquid level adjusting screw sleeve; 7—Flip plate; 8—Cathode plate; 9—Circulation inlet pipe; 10—Circulation return pipe; 11—Adjusting seat. Detailed Implementation

[0051] The following detailed description of the implementation process of the present invention, in conjunction with the accompanying drawings and embodiments, ensures the operability and repeatability of the technical solution.

[0052] Example 1: Tantalum block breakdown voltage test

[0053] This embodiment uses the breakdown voltage testing device and system of the present invention to perform high-precision breakdown voltage testing on tantalum block samples, verifying the device's multi-channel synchronous testing efficiency and environmental stability control capabilities.

[0054] 1. Test setup

[0055] (1) As Figure 1 and Figure 2 As shown, 10 independent slots are set inside the test tank 1. Each slot is equipped with a set of cathode plates 8 and product steel bars 4. The product steel bars 4 are fixed to the top of the tank by the product steel bar support 3. The adjustment seat 11 is fixed to the side wall of the test tank. The adjustment positioning screw 2 is connected to the adjustment seat 11 by thread and the vertical height of the product steel bars 4 is adjusted by the adjustment positioning screw 2 (adjustment range 0-15mm).

[0056] (2) The circulating inlet pipe 9 and the circulating return pipe 10 are respectively connected to the energy liquid storage device and the return device. The inlet flow rate is controlled at 1.5L / min and the valve is precisely adjusted by stepper motor control.

[0057] (3) Install the tipping plate 7, with serrated overflow teeth (1mm tooth height, 3mm tooth spacing) on ​​the top. By rotating the liquid level adjusting screw sleeves 6 located at the four corners of the test tank, the horizontality of the tank can be finely adjusted to ensure synchronous overflow of liquid at both ends of the tipping plate, preventing excessive overflow on one side or local distortion of the electric field, and improving test stability and repeatability. This structure requires no complex mechanisms; technicians can directly achieve precise liquid level adjustment based on this disclosure, ensuring liquid level fluctuation ≤ ±0.2mm.

[0058] (4) The cathode plate 8 is arranged opposite to the sample 5 to be tested. The cathode size is at least 30 mm larger than the tantalum block to ensure that there is a gap of about 15 mm between the tantalum block and the cathode wall in each direction. This can form a relatively uniform electric field distribution and avoid excessively high local electric field strength at the edge of the tantalum block.

[0059] 2. Test solution preparation and temperature control initialization

[0060] (1) Prepare a test solution containing ethylene glycol and nitric acid in a volume ratio of 3:1, and adjust the conductivity to 2.0 μS / cm at room temperature.

[0061] (2) Inject the solution into the test tank, heat it to 50°C using the PID temperature control module, and maintain the temperature fluctuation ≤ ±0.5°C.

[0062] 3. Sample mounting and electric field optimization

[0063] (1) Ten tantalum blocks with dimensions of 10mm×10mm×5mm and weight of 2.5g±0.1g were selected as the test samples 5.

[0064] (2) The samples are spot welded to the steel strip 4 of the product. The immersion depth of each sample in the solution is controlled within 8mm, and the immersion depth error is ≤±0.1mm.

[0065] (3) Adjust the liquid level to a stable overflow state of the tipping plate, detect the electric field strength deviation ≤5%, and ensure that each sample is in a uniform electric field.

[0066] 4. Boost rate self-tuning and test execution

[0067] (1) Input sample parameters (weight 2.5g, preset current density 0.5A / m). 2 Using the boost rate formula:

[0068] v = k·I 密度 ·W 坯块 / S 接触面积

[0069] Among them, the material property coefficient k = 0.12, and the electrode contact area S = 0.001m². 2 The calculated boost rate is v = 150 V / s.

[0070] (2) Apply voltage to each channel independently in constant current mode until the sample breaks down.

[0071] 5. Breakdown determination and data acquisition

[0072] (1) The data acquisition module monitors the voltage and current curves in real time at a sampling frequency of 1MHz.

[0073] (2) When the voltage value drops by more than 50% within 1ms and the current value rises to more than 10 times the initial value, the system automatically determines a breakdown event.

[0074] (3) Record the peak voltage at the moment of breakdown as the breakdown voltage value, and generate test reports for each channel simultaneously.

[0075] 6. Experimental Comparison and Results

[0076] (1) Ten samples were tested under dynamic liquid level control conditions. The average breakdown voltage was 1202V, with a standard deviation of 1.1%.

[0077] (2) In a comparative test without the use of dynamic liquid level control, the standard deviation of breakdown voltage increased to 4.5%.

[0078] (3) This shows that the dynamic control of liquid level and the optimization design of electric field of the present invention can effectively improve the consistency and reliability of test results.

[0079] Example 2: Breakdown Voltage Test of Niobium Oxide Cylindrical Block

[0080] 1. Test conditions adjusted

[0081] Cathode plate spacing: For niobium oxide cylindrical blocks, the cathode plate spacing is adjusted to 15mm.

[0082] Solution temperature: Set the temperature controller to 30℃, adjust the PID parameters to proportional band 1.0, integral time 90s, and derivative time 15s.

[0083] 2. Sample installation

[0084] The niobium oxide cylindrical block (size Φ5mm×H5mm) is spot welded to the product steel strip (4) and immersed to a depth of 5mm.

[0085] 3. Details of Penetration Detection

[0086] The boost rate was set to 10V / s (based on the weight of the niobium oxide cylindrical block of 0.50g). At the moment of breakdown, the voltage dropped from 450V to 212V (52.9%), and the current increased from 1mA to 12mA (12 times). The system locked the breakdown voltage at 450V within 1ms.

[0087] 4. Data Validation

[0088] The test was repeated three times, with breakdown voltages of 450V, 448V, and 452V respectively, and a standard deviation of 0.4%, verifying the high repeatability of the system (breakdown determination accuracy ≥99%).

[0089] This invention utilizes a liquid level adjustment and dynamic temperature control system to ensure a highly stable testing environment, effectively reducing data deviations caused by environmental fluctuations.

[0090] By employing independent voltage boost and dual-threshold breakdown determination, the breakdown moment is accurately captured, ensuring the authenticity and consistency of the breakdown voltage data.

[0091] The self-tuning mechanism for boost rate automatically optimizes the testing process based on different materials and sample sizes, improving the system's adaptability and intelligence.

Claims

1. A multi-type non-ferrous metal breakdown voltage testing device, comprising a test tank (1), a temperature and humidity control system, an electrode module, a temperature control module, a power supply module, and a data acquisition module, characterized in that: The test slot (1) is provided with multiple independent slots, each slot is used to fix a test sample (5), and each slot corresponds to a set of electrodes; The electrode module includes a cathode plate (8) disposed in each slot and arranged opposite to the sample (5) to be tested, and an adjustable product steel bar (4) for supporting the sample (5), wherein the cathode plate (8) and the sample (5) form a locally symmetrical electric field distribution, and the height of the product steel bar (4) can be adjusted by adjusting the positioning screw (2) and the product steel bar support (3) to control the immersion depth of the sample (5) to be tested; The temperature and humidity control system includes a circulating inlet pipe (9), a circulating return pipe (10), a tilting plate (7), and a liquid level adjusting screw sleeve (6). Through circulating flow and liquid level control, the liquid level of the test solution is kept constant and the overflow is uniform. The temperature control module includes a temperature-sensing thermocouple and a heating element, and maintains the temperature fluctuation range of the test solution within ±0.5℃ through a temperature controller; The data acquisition module includes a voltage sensor and a current sensor with a response speed of microseconds. It synchronously acquires voltage drop and current change data at the moment of breakdown and determines the breakdown event through a threshold comparison algorithm. The power module automatically calculates the boost rate based on the input sample parameters and applies voltage independently to each slot in a constant current mode until the sample breaks down.

2. The apparatus according to claim 1, characterized in that: The top of the liquid-turning plate (7) is provided with a serrated overflow structure. The liquid level adjusting screw sleeve (6) is used to adjust the overall level of the test tank (1) so as to achieve uniform overflow of the energizing liquid at both ends of the liquid-turning plate and ensure the stability of the liquid level and the consistency of the electric field.

3. The apparatus according to claim 1, characterized in that: The cathode plate (8) is coated with a platinum coating, and the distance between the cathode plate (8) and the side wall of the test tank (1) is 3 to 5 times the thickness of the sample (5) being tested, so as to eliminate edge electric field distortion and maintain uniform electric field distribution.

4. The apparatus according to claim 1, characterized in that: The product steel bar (4) is made of stainless steel and covered with an aluminum oxide insulation layer with a thickness of 50-100μm. The product steel bar (4) has multiple equally spaced welding points for mounting multiple test samples (5).

5. The apparatus according to claim 1, characterized in that: The temperature control module uses a PID controller to dynamically adjust the power output of the heating element based on the difference between the real-time temperature fed back by the thermocouple and the set temperature, so that the temperature fluctuation of the test solution is controlled within ±0.5℃.

6. The apparatus according to claim 1, characterized in that: The data acquisition module also includes a noise filtering circuit, which uses a differential amplifier and a low-pass filter with a cutoff frequency of 10kHz to eliminate high-frequency interference signals.

7. The apparatus according to claim 1, characterized in that: In the threshold comparison algorithm, the condition for determining a breakdown event is: within 1ms, the voltage value drops by more than 50% of the current value, and the current value rises to more than 10 times the initial value.

8. The apparatus according to claim 1, characterized in that: The water inlet direction of the circulating liquid inlet pipe (9) is arranged perpendicular to the arrangement direction of the slots in the test tank (1), and each slot is provided with an independent water supply pipe. The flow rate is adjusted by a stepper motor-driven valve to ensure a constant liquid level.

9. The apparatus according to claim 1, characterized in that: The product steel bar support (3) is fixed to the top of the test groove (1). The product steel bar (4) is moved up and down by the threaded adjustment positioning screw (2). The adjustment range is 0-15mm.

10. The apparatus according to claim 1, characterized in that: The formula for calculating the boost rate in the power module is as follows: v = k·I density·W billet / S contact area Where v is the voltage boost rate, k is the material property coefficient, I density is the preset current density, W billet is the billet weight, and S contact area is the contact area between the electrode and the sample.

11. A breakdown voltage testing system for multiple types of non-ferrous metals, characterized in that, include: The breakdown voltage testing apparatus as described in any one of claims 1 to 10; The central control unit is used to automatically allocate test channels based on the input sample parameters, including weight, material type and target current density, and generate independent boost rate commands for each channel. A multi-channel data acquisition module is connected to the voltage / current sensor of the test device to synchronously acquire the voltage and current signals of each channel, with a sampling frequency of not less than 1MHz; The breakdown determination module detects sudden voltage drops and sudden current increases in each channel and determines breakdown based on a threshold comparison algorithm. The feedback control module is used to dynamically adjust the flow rate of the liquid level adjusting screw sleeve (6) and the circulating liquid inlet pipe (9) according to the liquid level fluctuation detection results, so as to ensure that the liquid level fluctuation amplitude is ≤ ±0.2mm.

12. A method for testing the breakdown voltage of multiple types of non-ferrous metals, characterized in that, Includes the following steps: (1) Solution preparation and temperature control initialization: Prepare a test solution of ethylene glycol and nitric acid, and adjust the conductivity to 1.5-2.5 μS / cm; inject the solution into the test tank (1), and heat it to 30-80℃ using a temperature control module while maintaining temperature fluctuations ≤ ±0.5℃; (2) Sample mounting and electric field adjustment: The sample to be tested (5) is welded to the product steel strip (4). The immersion depth of the sample is controlled by adjusting the positioning screw (2) to 5-10 mm. The liquid level adjusting screw sleeve (6) is adjusted to control the overflow gap of the liquid tipping plate (7) so that the electric field uniformity deviation is ≤5%. (3) Parameter self-tuning and boost test: Input the sample weight and preset current density. The central control unit calculates the parameters of each channel according to the boost rate formula. The power module applies boost in constant current mode, with a boost rate range of 10 to 200V / s. (4) Determination and recording of breakdown events: The voltage and current signals of each channel are collected synchronously. When the voltage drops by ≥50% and the current rises by ≥10 times within 1ms, a breakdown event is determined to have occurred. The breakdown voltage value is recorded and a test report is generated.

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