Atmospheric corrosion monitoring device based on quartz crystal microbalance

Abstract

The utility model relates to an atmospheric corrosion monitoring device based on a quartz crystal microbalance, which is characterized in that a measuring circuit is connected with an MCU (Microprogrammed Control Unit), collects an oscillation signal generated by a quartz crystal wafer sensor, identifies the frequency of the oscillation signal, and transmits the frequency of the oscillation signal to the MCU; and the MCU is used for calculating the oxidation weight gain rate and the corrosion rate of the metal film. The battery is connected with and supplies power to the measuring circuit; the charging circuit is connected with the battery and provided with a charging interface. The atmospheric corrosion monitoring device based on the quartz crystal microbalance can reach nanogram resolution, so that the mass gain of metal surface corrosion products in the atmospheric environment can be monitored on line in situ, and the sensitivity of monitoring the overall corrosion can meet the requirements that the magnitude order of 10-9g is difficult to realize by other types of sensors and the corrosion resolution is less than or equal to 10nm; and the monitoring precision of metal corrosion is greatly improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to environmental monitoring technical field especially relates to a kind of atmospheric corrosion monitoring devices based on quartz crystal microbalance. BACKGROUND

[0002] Metal is corroded due to the attachment of water, salt mist, SO2, CO2 and other substances on its surface under natural atmospheric conditions. Atmospheric corrosion is the most common, largest in number, most widespread and most destructive form of corrosion for metal materials. This is because metal is exposed to atmospheric environment more often than other media. Outdoor high-rise steel frames, bridges, cars, ships and various metal structures are constantly corroded by the atmosphere. Especially in areas with high salt content, such as marine atmospheric environment, there are also salt, microorganisms and decomposed organic matter, high temperature and humidity, which can cause rust, performance loss and accidents for precision electronic devices, bridge suspension cables, reinforced structures and chemical equipment.

[0003] Current corrosion monitoring devices often have insufficient precision and other problems, and are only detected when metal corrosion is severe. For example, the atmospheric environment corrosion monitoring device provided by Chinese invention patent CN108872048A collects the corrosion current of metal materials in the atmospheric environment and the temperature and humidity information of the atmospheric environment to evaluate the corrosion degree of the metal part of the service equipment. However, its detection accuracy still needs to be improved. SUMMARY

[0004] The utility model provides a kind of atmospheric corrosion monitoring devices based on quartz crystal microbalance to the technical problem of low metal corrosion monitoring precision in prior art.

[0005] The technical solution of the utility model to solve the above technical problem is as follows:

[0006] A kind of atmospheric corrosion monitoring devices based on quartz crystal microbalance, comprising: quartz chip sensor, measurement circuit, battery, charging circuit and MCU;

[0007] The surface of the quartz chip of the quartz chip sensor is plated with a metal film;

[0008] The quartz chip sensor is connected to the measurement circuit, and the measurement circuit loads an alternating voltage signal onto the metal film on both sides of the quartz chip;

[0009] The measurement circuit is connected with the MCU, the measurement circuit collects the oscillation signal generated by the quartz crystal sensor and identifies the frequency of the oscillation signal, and the frequency of the oscillation signal is transmitted to the MCU; the MCU is used for calculating the oxidation weight gain rate and the corrosion rate of the metal thin film;

[0010] The battery is connected with the measurement circuit and supplies power; the charging circuit is connected with the battery, and the charging circuit is provided with a charging interface.

[0011] Further, it further comprises a communication module;

[0012] The communication module is connected with the MCU;

[0013] The communication module is used for external expansion access to the PLC industrial network.

[0014] Further, it further comprises a 4G Internet of Things wireless module;

[0015] The 4G Internet of Things wireless module is connected with the communication module and communicates, and the 4G Internet of Things wireless module communicates with a server.

[0016] Further, it further comprises an upper computer display module;

[0017] The upper computer display module is connected with the MCU;

[0018] The upper computer display module is used for displaying the frequency of the oscillation signal generated by the quartz crystal sensor.

[0019] Further, it further comprises a lower shell, a box cover and a lining plate;

[0020] The lower shell is arranged as a semi-closed structure with an open upper end;

[0021] The battery is fixed to the bottom of the inner side of the lower shell;

[0022] The lining plate is fixed to the inner side of the lower shell, and the lining plate is arranged above the battery;

[0023] The measurement circuit and the charging circuit are arranged integrated on a PCB circuit board, and the PCB circuit board is fixed to the upper end of the lining plate;

[0024] The box cover is detachably fixed to the upper end of the lower shell, and the quartz crystal sensor is integrated in the box cover.

[0025] Further, the quartz crystal sensor is provided with two.

[0026] Further, the measurement circuit comprises a Schmidt oscillator, a D flip-flop and a frequency counter;

[0027] The quartz wafer sensor is connected with the D flip-flop through the Schmidt oscillator; the D flip-flop is connected with the MCU through the frequency counter.

[0028] The quartz crystal microbalance-based atmospheric corrosion monitoring device provided by the utility model has at least the following advantages or benefits:

[0029] The quartz wafer surface of the quartz wafer sensor is plated with a metal film. The quartz wafer sensor is connected with a measurement circuit, and the measurement circuit loads an alternating voltage signal on the metal film on both sides of the quartz wafer. The measurement circuit is connected with the MCU, the measurement circuit collects an oscillation signal generated by the quartz wafer sensor and identifies the frequency of the oscillation signal, and the frequency of the oscillation signal is transmitted to the MCU; the MCU is used for calculating the oxidation weight gain rate and the corrosion rate of the metal film. The battery is connected with the measurement circuit and supplies power; the charging circuit is connected with the battery, and the charging circuit is provided with a charging interface. The quartz crystal microbalance-based atmospheric corrosion monitoring device can achieve nanogram-level resolution, so that the mass gain of the corrosion product on the metal surface in the atmospheric environment can be monitored in situ and online, and the sensitivity of the whole corrosion monitoring can reach 10 -9 orders of magnitude, and the corrosion resolution is ≤10 nm, thereby greatly improving the monitoring precision of the metal corrosion. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 The quartz crystal microbalance-based atmospheric corrosion monitoring device structure schematic view provided by the utility model embodiment is shown in the figure;

[0031] Figure 2 The quartz crystal microbalance-based atmospheric corrosion monitoring device circuit principle block diagram provided by the utility model embodiment is shown in the figure;

[0032] Figure 3 The corrosion monitoring instrument analysis software page provided by the utility model embodiment is shown in the figure;

[0033] Figure 4 The corrosion weight gain and corrosion rate-time curve diagram of clean copper (a) and pre-deposited 45 μg cm-2 NaCl copper (b) exposed for 24 h under 90% relative humidity and different temperatures is shown in the figure.

[0034] In the drawings, the components represented by each reference numeral are listed as follows:

[0035] 1 - upper cover, 2 - O-shaped ring, 3 - quartz wafer, 5 - PCB circuit board, 6 - backing plate, 7 - battery, 8 - lower shell 8, 9 - navigation plug, 10 - indicator light, 11 - second PCB circuit board. DETAILED DESCRIPTION

[0036] The utility model provides a kind of atmospheric corrosion monitoring device based on quartz crystal microbalance to the technical problem of low precision of metal corrosion monitoring in prior art.

[0037] The technical solutions in the embodiments of the utility model will be apparently and completely described in conjunction with the drawings in the embodiments of the utility model, and apparently, the described embodiments are only part of the embodiments of the utility model, not all the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by the person skilled in the art without creative labor belong to the scope of protection of the utility model.

[0038] Referring to the drawings and Figure 2 The utility model embodiment provides a kind of atmospheric corrosion monitoring device based on quartz crystal microbalance, it include: quartz wafer sensor, measurement circuit, battery 7, charging circuit and MCU.Equally:

[0039] Quartz wafer 3 surface of quartz wafer sensor is plated with metal film.Quartz wafer sensor is connected with measurement circuit, and measurement circuit loads alternating voltage signal on the metal film on the two sides of quartz wafer 3.Measurement circuit includes: schmitt oscillator, D flip-flop and frequency counter;Quartz wafer sensor is connected with D flip-flop by schmitt oscillator;D flip-flop is connected with MCU by frequency counter.

[0040] Measurement circuit is connected with MCU, and measurement circuit collects the oscillation signal generated by quartz wafer sensor and identifies the frequency of oscillation signal, and the frequency of oscillation signal is delivered to MCU.Measurement circuit is used to measure the mass change after the corrosion of the metal film on the surface of quartz wafer 3, and alternating voltage signal is loaded on the metal film on the two sides of quartz wafer 3, due to piezoelectric effect, quartz wafer 3 immediately starts to oscillate (5~8 MHz), when the metal film increases in weight due to oxidation, it will cause the frequency of crystal oscillation to drop.Schmitt oscillator is arranged to square wave from sine wave, and then is sent into 48-bit frequency counter, can distinguish to 0.01Hz frequency offset, is used for in-situ monitoring trace corrosion in atmospheric environment, and has very high sensitivity (reaches 10 nm / a), is the higher sensitivity in the prior art of various corrosion sensors.

[0041] MCU is used to calculate the oxidation weight gain rate and corrosion rate of metal film.MCU collects the frequency value of input by 32-bit high-speed MCU, uses internal 32bit timer to capture input frequency, records the frequency change value of quartz wafer 3 under different environments, to be used for data research in electrochemistry field, and the accuracy of difference frequency measurement value can reach 0.1Hz.

[0042] The battery 7 is connected with the measuring circuit and supplies power; the charging circuit is connected with the battery 7, and the charging circuit is provided with a charging interface; the charging circuit adopts a charging management circuit commonly used in the field.

[0043] In a preferred embodiment of the utility model, communication module and 4G internet of things wireless module are further provided. The communication module is connected with MCU. The communication module is used for externally expanding and accessing PLC industrial network. The 4G internet of things wireless module is connected with the communication module and communicates, and the 4G internet of things wireless module communicates with a server. The communication module adopts RS485 bus structure, can form multi-machine communication network, and the farthest transmission distance is 1000 meters. The communication scheme supports standard Modbus protocol, and it is convenient to access existing PLC industrial network. The 4G internet of things wireless module can be selected and configured, a remote cloud monitoring platform can be formed, historical data is wirelessly transmitted to public or private cloud servers through timing, and ISO9223-2012 standard can be installed to classify air corrosiveness. MCU, the communication module and the 4G internet of things wireless module communicate with external equipment through the aviation plug 9.

[0044] In a preferred embodiment of the utility model, host computer display module is further provided. The host computer display module is connected with MCU. The host computer display module is used for displaying the frequency of the oscillation signal generated by the quartz crystal sensor. The data analysis software of the host computer software display module can not only display the original frequency of the quartz crystal sensor, but also can display the relative frequency, that is, the current measured frequency is subtracted from the initial frequency of the data sequence (which can be specified by a user through a mouse or input), the quality gain-time curve can be displayed, finally, the oxidation weight gain rate m of the plated metal =d (m) / dt and the corrosion rate k are calculated according to the quality increase m =t curve.

[0045] The utility model embodiment can support multi-channel expansion through internal switch circuit control, control the channel number to 1-99, and simultaneously test 1-99 kinds of metal materials in atmospheric test.

[0046] The utility model provides a preferred embodiment provided in still have: lower housing 8, box cover and lining 6. Lower housing 8 is set up as the half -closed structure of open upper end. Battery 7 is fixed at the bottom of the inboard of lower housing 8. Lining 6 is fixed at the inboard of lower housing 8, and lining 6 is set in the top of battery 7. Measuring circuit and charging circuit set integration are set on PCB circuit board 5, and PCB circuit board 5 is fixed on the upper end of lining 6. Box cover is detachably fixed at the upper end of lower housing 8, and quartz crystal sensor is integrated on the box cover, and O -ring 2 for sealing is arranged between quartz crystal 3 and the box cover, specifically, two upper caps 1 are arranged on the box cover, the upper cap 1 is provided with a plurality of through holes, the quartz crystal 3 is arranged on the inboard of the upper cap 1, and the housing is further provided with a signal indicator lamp 10. The second PCB circuit board 11 can be arranged in the housing, the second PCB circuit board 11 is used for driving temperature sensor, humidity sensor and air pressure sensor, and is used for collecting temperature signal, humidity signal and air pressure signal and then displaying by display equipment.

[0047] The configured quartz crystal sensor is very sensitive to the overall corrosion of metal, a few hundred nanometer thick metal film is formed on the surface of the quartz crystal 3 by adopting vacuum evaporation technology, two channel quartz crystal sensors are connected, are used as detection crystal oscillator respectively, output two independent oscillation signals through the oscillation circuit, and are input to the counter pin of the single-chip microcomputer through the shaping circuit (D trigger) for measurement. The 32-bit high-speed MCU is used to collect the input frequency value, the internal 32-bit timer is used to capture the input frequency, the frequency change value of the quartz crystal 3 in different environments is recorded, and the data in the electrochemical field is researched. After measurement, the atmospheric corrosion monitoring device based on the quartz crystal microbalance has a built-in USB port, historical data can be downloaded on site, the monitor can be connected with a low-power 4G wireless module, and historical data can be wirelessly transmitted to a public or private cloud server at a fixed time. The monitor has a built-in large-capacity battery 7, and can work continuously for 2 years in a typical working state. The matching data analysis software can not only display the original frequency of the quartz crystal sensor, but also display the relative frequency, that is, the current measured frequency is subtracted from the initial frequency of the data sequence (which can be specified by the user through the mouse or input), the mass gain-time curve, that is, Δm~t, can be displayed, and the mass gain-time curve is Figure 4 Finally, the derivative of the mass gain Δm~t curve is calculated, and the oxidation weight gain rate m=d(m) / dt and the corrosion rate k of the plated metal are calculated.

[0048] Referring to Figure 3 And Figure 4, the weight gain of clean and contaminated copper in atmospheric environment was continuously monitored, among which the weight gain curves of contaminated copper-coated quartz wafer sensor wafer (pre-deposited 45 μg cm-2 of NaCl salt particles) exposed to 90% RH and different temperatures in air with and without gas-phase inhibitor 2-PI were shown. It can be seen that the mass gain of contaminated copper-coated wafer after 24 hours exposure under the same conditions will increase by two orders of magnitude compared with clean copper, which is due to the deliquescence of NaCl salt particles on the surface of contaminated copper under high humidity, forming a thin liquid film, and further accelerating the process of atmospheric corrosion of copper. Compared with the case without 2-PI, the mass gain of the surface of contaminated copper will decrease after the introduction of gas-phase inhibitor 2-PI, which shows that 2-PI has a strong inhibitory effect on the process of copper atmospheric corrosion. In addition, with the increase of temperature, the mass gain of the surface of contaminated copper after the introduction of 2-PI is significantly reduced, indicating that high temperature improves the corrosion inhibition efficiency of 2-PI.

[0049] The above data show that the atmospheric corrosion monitoring device based on the quartz crystal microbalance can monitor the degree of atmospheric corrosion of copper with high sensitivity. If other metals are plated on the wafer, it can also be used to monitor the atmospheric corrosion rate of specific metals.

[0050] The quartz crystal microbalance-based atmospheric corrosion monitoring device provided by the embodiments of the present application has at least the following advantages or benefits:

[0051] The quartz crystal microbalance-based atmospheric corrosion monitoring device provided by the embodiments of the present application has extremely high sensitivity. The present application can achieve nanogram resolution, so it can monitor the mass gain of the corrosion product on the surface of the metal in the atmospheric environment in situ and online, and the sensitivity of the whole corrosion monitoring can reach 10 -9 gram order of magnitude, and the corrosion resolution is ≤10 nm, which can more effectively monitor the overall corrosion condition than other existing sensors.

[0052] The quartz crystal microbalance-based atmospheric corrosion monitoring device provided by the embodiments of the present application is convenient for communication, has various modes, and can establish a cloud monitoring system. The RS485 bus structure can be used to form a multi-machine communication network, and the farthest transmission distance is 1000 meters. The communication scheme supports the standard Modbus protocol, which facilitates the access to the existing PLC industrial network, or forms a remote monitoring network through a wireless serial port server module.

[0053] The quartz crystal microbalance-based atmospheric corrosion monitoring device provided by the embodiments of the present application can realize multi-channel expansion. The present application can support multi-channel expansion through internal switch circuit control, control the number of channels to 1-99, and simultaneously test the atmospheric test of 1-99 kinds of metal materials.

[0054] The atmospheric corrosion monitoring device based on the quartz crystal microbalance has high measurement precision. During measurement of the difference frequency signal, the frequency value captured for the first time is used to set the square wave cycle number, and the greater the frequency value captured for the first time, the more the cycle number, so that the measurement precision is improved. After the data of multiple cycles are measured, bubble sorting and oversampling are performed, and then the average value is calculated, so that the precision is improved.

[0055] In the description of the utility model, it needs to explain, unless another explicit stipulation and limit, term " install " " link " " connection " should do broad sense understanding, for example, can be fixed connection, also can be detachable connection, can be direct link, also can indirectly link through intermediate medium.

[0056] The above only is the preferred embodiment of the utility model, and does not use to limit the utility model, and any modification, equivalent replacement, improvement etc. that is made within the spirit and principle of the utility model should be contained in the protection scope of the utility model.

Claims

1. An atmospheric corrosion monitoring device based on a quartz crystal microbalance, characterized by: It comprises: a quartz wafer sensor, a measurement circuit, a battery, a charging circuit and an MCU; the surface of the quartz wafer of the quartz wafer sensor is plated with a metal film; the quartz wafer sensor is connected with the measurement circuit, and the measurement circuit loads an alternating voltage signal on the metal film on both sides of the quartz wafer; the measurement circuit is connected with the MCU, the measurement circuit collects the oscillation signal generated by the quartz wafer sensor and identifies the frequency of the oscillation signal, and the frequency of the oscillation signal is transmitted to the MCU; the MCU is used for calculating the oxidation weight gain rate and the corrosion rate of the metal film; the battery is connected with the measurement circuit and supplies power; the charging circuit is connected with the battery, and the charging circuit is provided with a charging interface.

2. The quartz crystal microbalance based atmospheric corrosion monitoring device according to claim 1, characterized in that: It further comprises: a communication module; the communication module is connected with the MCU; the communication module is used for external expansion access to PLC industrial network.

3. An atmospheric corrosion monitoring apparatus based on a quartz crystal microbalance according to claim 2, characterized in that: It further comprises: a 4G Internet of Things wireless module; the 4G Internet of Things wireless module is connected with the communication module and communicates, and the 4G Internet of Things wireless module communicates with a server.

4. The quartz crystal microbalance based atmospheric corrosion monitoring device of claim 1, wherein: It further comprises: an upper computer display module; the upper computer display module is connected with the MCU; the upper computer display module is used for displaying the frequency of the oscillation signal generated by the quartz wafer sensor.

5. The quartz crystal microbalance based atmospheric corrosion monitoring device of claim 1, wherein: It further comprises: a lower shell, a box cover and a lining plate; the lower shell is provided as a semi-closed structure with an open upper end; the battery is fixed at the bottom of the inner side of the lower shell; the lining plate is fixed on the inner side of the lower shell, and the lining plate is arranged above the battery; the measurement circuit and the charging circuit are integrated on a PCB circuit board, and the PCB circuit board is fixed on the upper end of the lining plate; the box cover is detachably fixed on the upper end of the lower shell; the quartz wafer sensor is integrated in the box cover.

6. The quartz crystal microbalance-based atmospheric corrosion monitoring device of claim 1, wherein: The quartz wafer sensor is provided with two.

7. The quartz crystal microbalance-based atmospheric corrosion monitoring apparatus according to claim 1, characterized by: The measurement circuit comprises a Schmidt oscillator, a D flip-flop and a frequency counter; the quartz wafer sensor is connected with the D flip-flop through the Schmidt oscillator; the D flip-flop is connected with the MCU through the frequency counter.

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