Failure detection method and regulation and control system for corrosion inhibition treatment of silver alloy sheet-shaped electric contact sheet

Abstract

The invention discloses a failure detection method and a regulation and control system for corrosion inhibition treatment of a silver alloy sheet-shaped electric contact chip. The failure detection method comprises the following steps: S1, acquiring the thickness of an organic protective film on the surface of the electric contact chip as dorg and the thickness of an oxide film as dox in real time through an elliptical polarization spectrum; s2, inputting the thickness dorg of the organic protective film or the thickness dox of the oxide film into a preset film thickness-contact resistance correlation model, and outputting to obtain a predicted contact resistance value Rc; s3, when the predicted contact resistance Rc is less than or equal to 25 m omega, judging that the electric contact piece is qualified, and when the predicted contact resistance Rcgt is obtained; and when the voltage is 25 m omega, judging that the electric contact piece is invalid, triggering a back-end processing flow, and returning to a front-end cleaning procedure. According to the method, the dynamic change effect of the predicted contact resistance value Rc is utilized to judge the failure condition of the electric contact chip in the front-end cleaning process, the bad reasons of the cleaning tank are checked in time, and the timeliness and reliability of failure detection of the electric contact chip are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of surface treatment production of current-carrying, breaking circuit electric contact pieces in the manufacture of electrical switches, relays, contactors, circuit breakers and the like, in particular to a failure detection method and regulation system for corrosion inhibition treatment of silver alloy electric contact pieces. BACKGROUND

[0002] The electric contact piece is one of the key components for carrying current and breaking circuit in the manufacture of electrical switches, relays, contactors, circuit breakers and the like, and its quality is a major factor determining the service life of electrical equipment. Silver-based contacts have been the preferred material for high-end contacts for a long time due to their excellent thermal and electrical conductivity, resistance to arc ablation and low self-loss. Silver alloy sheet-shaped electric contact devices, as core electric contact components of electrical equipment, usually use silver-based materials to achieve excellent electrical conductivity, but the surface is easily corroded by environmental media during production and use. H2O molecules and Cl - corrosive ions in the environmental medium can also penetrate to the interface through silver layer defects, exacerbating corrosion and deteriorating contact resistance stability. This corrosion is hidden and often not discovered until the product testing stage. The residual corrosive contaminants themselves have high resistance characteristics, or can induce subsequent continuous corrosion (including accelerated oxidation of alloy elements), ultimately leading to a significant increase in contact resistance and deterioration of stability, affecting the on-off reliability of the equipment.

[0003] To solve the above-mentioned electric corrosion problem, an inhibitor is usually added during the cleaning process of the silver alloy sheet-shaped electric contact piece. The inhibitor forms an effective release film on the surface of the silver alloy sheet-shaped electric contact piece, and a dense protective layer is built on the metal surface. This protective layer can effectively isolate the metal from direct contact with H2O, Cl - and other corrosive media, thereby inhibiting the metal corrosion reaction and effectively protecting the metal surface of the silver alloy sheet-shaped electric contact piece. Of course, in the back-end cleaning and protection process of the silver alloy sheet-shaped electric contact piece, contact resistance detection is performed for sampling inspection to ensure that an effective release film is formed on the surface of the silver alloy sheet-shaped electric contact piece, thereby ensuring that the silver alloy sheet-shaped electric contact piece is effectively protected. However, in the existing technology, contact resistance detection relies on destructive sampling inspection, which is low in efficiency, cannot be fully covered and is prone to lag. In the process of detection, when a worker detects that one of the silver alloy sheet-shaped electric contact pieces has a release film failure, the silver alloy sheet-shaped electric contact pieces in the back-end cleaning process have actually occurred in batches. SUMMARY

[0004] In response to the existing problems, the present invention needs to design a detection method that can quickly and in real time determine the failure of the corrosion inhibition film of the silver alloy sheet electrical contact piece during the cleaning process, so as to ensure the quality of the cleaning process of the silver alloy sheet electrical contact piece and improve the yield rate of the silver alloy sheet electrical contact piece.

[0005] To address this issue, the present invention provides a technical solution: a failure detection method for corrosion inhibition treatment of a silver alloy electrical contact sheet, comprising the following steps:

[0006] S1: Obtain the thickness of the organic protective film on the surface of the electrical contact piece in real time by ellipsometry spectroscopy (d). org and the oxide film thickness is d ox ;

[0007] S2: The thickness of the organic protective film is d org Or oxide film thickness d ox Input the preset film thickness-contact resistance correlation model and output the predicted contact resistance value R c ;

[0008] S3: When predicting the contact resistance R c When the contact resistance R c When the resistance is >25 mΩ, the electrical contact piece is judged to be failed, triggering the back-end processing flow and returning to the front-end cleaning process.

[0009] The preset film thickness-contact resistance correlation model is constructed based on Holm contact theory and satisfies the following general form: R c =R const +R org +R ox (1)

[0010] (1) In the formula, R const is the shrinkage resistance independent of the film layer, in mΩ, and is calculated as follows:

[0011] R const =500×ρ×sqrt (π×H / F) (2)

[0012] ρ is the resistivity of the electrical contact material, in Ω·m, H is the hardness of the electrical contact material, in Pa, and F is the contact pressure, in N.

[0013] (1) In the formula, R org is the resistance function related to the thickness of the organic film, in mΩ, and is calculated as follows:

[0014] R org =ρ org ×d org ×10 -6 / Anom (3)

[0015] p org is the organic film resistivity, unit: Ω·m, d org is the organic film thickness, unit: nm, A nom is the nominal contact area of the electrical contact piece, unit: m 2 .

[0016] (1) in the formula, the R ox is the oxide film thickness related resistance function, unit: mΩ, which is calculated as follows:

[0017] R ox =h 2 ×d ox ×exp[4×π×d ox ×sqrt(2×m×Phi) / h] / [A nom ×e 2 ×sqrt(2×m×Phi )] (4)

[0018] Phi is the barrier height, unit: ev, h is the Planck constant, h=6.62607015×10 -34 J·s, m is the electron mass, m=9.1093837139×10 -28 g, e is the electron charge, e=1.6×10 -19 C (Coulomb).

[0019] Further, in step S3, the back-end processing flow is carried out according to the following method:

[0020] S4: when d ox > d1, it is determined that the pickling is insufficient; wherein d1 is the oxide film threshold, unit: nm;

[0021] S5: when d org< d2, it is determined that the corrosion inhibitor is invalid, and when d org > d3, it is determined that the corrosion inhibitor concentration is too high, wherein d2, d3 is the organic film threshold, unit: nm.

[0022] Wherein, d1, d2, d3 are determined according to the application scene of silver alloy sheet-shaped electrical contact device (such as high-voltage circuit breaker, low-voltage switch) and corrosion inhibitor system, typical value d1 is 0.8~1.2nm, d2 is 2.0~2.8nm, d3 is 3.4~4.0nm.

[0023] The present application also designs a detection and control system for the failure detection method of silver alloy electrical contact piece corrosion treatment, including:

[0024] The ellipsometric spectrum detection unit comprises a station for positioning the electrical contact piece and a detection device for performing ellipsometric scanning on the station, the detection device is electrically connected with a control mainboard, the control mainboard displays the thickness d of the organic protective film measured by the detection device in real time org and the thickness d of the oxide film ox The control mainboard transmits the thickness d of the organic protective film org and the thickness d of the oxide film ox to a next processing unit

[0025] The resistance prediction unit is internally provided with the preset film thickness-contact resistance correlation model, receives the thickness d of the organic protective film org and the thickness d of the oxide film ox transmitted from the control mainboard, and obtains a predicted R c value according to the preset film thickness-contact resistance correlation model through R const =R org +R ox +R c , and transmits the predicted R c value to a next processing unit

[0026] The process decision unit receives the R c value transmitted from the resistance prediction unit, and transmits an execution signal to a next processing unit when the predicted contact resistance R c >25 mΩ

[0027] The execution mechanism receives the execution signal from the process decision unit, and sorts the unqualified electrical contact piece into a corresponding rework process tank.

[0028] The present application uses the predicted contact resistance value R c to judge the quality of the cleaning process of the silver alloy sheet-shaped electrical contact piece, predicts the dynamic change effect of the predicted contact resistance value R c , and further comprehensively judges the failure of the electrical contact piece in the front-end cleaning process, so that the causes of the cleaning tank can be investigated in time according to the judgment of the detection method of the present application in the actual cleaning process, and the timeliness and reliability of the electrical contact piece failure detection are improved. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 It is a failure detection method for the silver alloy electrical contact piece corrosion treatment of the present application. DETAILED DESCRIPTION

[0030] The embodiments of the present application will be briefly described below in combination with the drawings.

[0031] Referring to the drawings Figure 1The method for detecting failure of corrosion inhibition treatment of silver alloy electrical contact pieces comprises the following steps:

[0032] S1: Obtain the thickness of the organic protective film on the surface of the electrical contact piece in real time by ellipsometry spectroscopy (d). org and the oxide film thickness is d ox ;

[0033] S2: The thickness of the organic protective film is d org Or oxide film thickness d ox Input the preset film thickness-contact resistance correlation model and output the predicted contact resistance value R c ;

[0034] S3: When predicting the contact resistance R c When the contact resistance R c When the resistance is >25 mΩ, the electrical contact is judged to be failed, triggering the back-end processing flow and returning to the front-end cleaning process;

[0035] The preset film thickness-contact resistance correlation model is constructed based on Holm contact theory and satisfies the following general form: R c =R const +R org +R ox (1)

[0036] (1) In the formula, R const is the shrinkage resistance independent of the film layer, in mΩ, and is calculated as follows:

[0037] R const =500×ρ×sqrt (π×H / F) (2)

[0038] ρ is the resistivity of the electrical contact material, in Ω·m, H is the hardness of the electrical contact material, in Pa, and F is the contact pressure, in N. (2) In the formula, sqrt represents the square root symbol;

[0039] (1) In the formula, R org is the resistance function related to the thickness of the organic film, in mΩ, and is calculated as follows:

[0040] R org =ρ org ×d org ×10 -6 / A nom (3)

[0041] ρ org is the resistivity of the organic film, in Ω·m, d org is the thickness of the organic film, in nm, A nomS is the nominal contact area of the electrical contact, in m 2 ;

[0042] (1) wherein, R ox is the oxide film thickness related resistance function, in mΩ, calculated as follows:

[0043] R ox =h 2 ×d ox ×exp[4×π×d ox ×sqrt(2×m×Phi) / h] / [A nom ×e 2 ×sqrt(2×m×Phi)] (4)

[0044] Phi is the barrier height, in ev, h is the Planck constant, h=6.62607015×10 -34 J·s, m is the electron mass, m=9.1093837139×10 -28 g, e is the electron charge, e=1.6×10 -19 C (Coulomb), sqrt in formula (4) represents square root.

[0045] In step S3, the back-end processing flow is carried out according to the following method:

[0046] S4: when d ox > d1, it is determined that pickling is insufficient; wherein, d1 is the oxide film threshold, in nm;

[0047] S5: when d org< d2, it is determined that the corrosion inhibitor is ineffective, and when d org > d3, it is determined that the corrosion inhibitor concentration is too high, wherein, d2, d3 are the organic film thresholds, in nm.

[0048] d1 is the oxide film threshold, and d2, d3 are the organic film thresholds, which are determined by the type of corrosion inhibitor and the type of electrical contact, and in this embodiment, when AgSnO2In2O3 contacts are used and the corrosion inhibitor is a methyl imidazole corrosion inhibitor system, d1 is 1.0 nm, d2 is 2.4 nm, and d3 is 3.5 nm.

[0049] The present application also designs a detection and control system for the failure detection method of the silver alloy sheet-shaped electrical contact corrosion treatment, comprising:

[0050] The ellipsometric spectrum detection unit comprises a work station for positioning the electrical contact and a detection device for ellipsometric scanning of the work station, and the detection device is electrically connected with a control mainboard, and the control mainboard displays the measured organic protective film thickness dorg and the oxide film thickness d ox , the control mainboard transmits the organic protective film thickness d org and the oxide film thickness d ox to a next processing unit;

[0051] An electrical resistance prediction unit, which is built-in with the preset film thickness-contact resistance correlation model, receives the organic protective film thickness d org and the oxide film thickness d ox transmitted from the control mainboard, and obtains a predicted R c value according to the preset film thickness-contact resistance correlation model, that is, R const = R org + R ox + R c , and transmits the predicted R c value to a next processing unit;

[0052] A process decision unit, which receives the R c value transmitted from the electrical resistance prediction unit, transmits an execution signal to a next processing unit when the predicted contact resistance R c > 25 mΩ;

[0053] An execution mechanism, which receives the execution signal from the process decision unit, sorts the unqualified electrical contact piece to a corresponding rework process tank.

[0054] Embodiment 1

[0055] In the cleaning process of the front end, no corrosion inhibitor is added, and the silver alloy sheet-shaped electrical contact piece after the cleaning process is detected. The electrical contact piece is AgSnO2In2O3 contact, the diameter of the electrical contact piece used is 4 mm, and the surface of the electrical contact piece is characterized by an ellipsometer (SENTECH, SEUV800, Germany). The instrument is equipped with a xenon lamp and a halogen lamp, the measurement range is 701 wavelength units of 200~900nm, and the organic protective film thickness d org = 0 nm and the oxide film thickness d ox = 1.22 nm of the surface of the electrical contact piece are obtained in real time by ellipsometric spectroscopy. Wherein, R const , the calculation formula of which is,

[0056] R const = 500×ρ×sqrt(π×H / F) (2)

[0057] (2) In the formula, ρ is the resistivity of silver 1.59×10 -8 Ω·m, and H is the hardness of silver 7.8456×10 8Pa, F is the contact pressure, in electrical switches, relays, contactors, circuit breakers and other devices, the contact pressure is usually 7g force, in this embodiment, the contact pressure is calculated according to 7g force, that is, F=0.0686 N.

[0058] R is calculated by formula (1) const =1.507 mΩ, which is determined by the inherent properties of the material and the contact pressure, and is irrelevant to the film layer.

[0059] In formula (1), R org is calculated as follows:

[0060] R org =ρ org ×d org ×10 -6 / A nom (3)

[0061] ρ org is the resistivity of the organic film, ρ org =0.78 Ω·m, A nom is the nominal contact area of the electrical contact piece, the diameter of the electrical contact piece is 4 mm, and the nominal contact area can be calculated as 1.256×10 -5 m 2 , R org =0 mΩ is calculated by formula (3).

[0062] In formula (1), R ox is the resistance function related to the thickness of the oxide film, which is dominated by the quantum tunneling effect of the metal surface oxide layer, and is calculated as follows:

[0063] R ox =h 2 ×d ox ×exp[4×π×d ox ×sqrt(2×m×Phi) / h] / [A nom ×e 2 ×sqrt(2×m×Phi)] (4)

[0064] Phi is the barrier height, with units of ev, and the barrier height of Ag2O is 3.0 eV, h is the Planck constant, h=6.62607015×10 -34 J·s, m is the electron mass, m=9.1093837139×10 -28 g, e is the electron charge, e=1.6×10 -19 C (Coulomb), and after simplification, formula (5) is obtained:

[0065] R ox =26×d oxxexp(9.8xd ox ) / A nom (5)

[0066] After calculation, R ox =39.33 mΩ, finally, the detection method of the application can obtain the predicted resistance value R c =R const +R org +R ox =40.84 mΩ, R c >25 mΩ, it is judged that the electrical contact piece fails, indicating that no etchant is added in the front-end cleaning process, and the electrical contact piece will easily bring about excessive corrosion effect in the acidic process, the thickness of the oxide film of the electrical contact piece is too thick, so that R ox is greatly higher, so that the predicted resistance value R c is greater than the critical value of 25 mΩ, through further judgment by the back-end processing flow, d2is 2.4 nm, d org< d2, it is determined that the corrosion inhibitor fails, that is, the concentration of the corrosion inhibitor is too low or there is no corrosion inhibitor, in the cleaning process, due to the insufficient effect of the corrosion inhibitor on the electrical contact piece, the corrosion inhibitor needs to be added or the concentration of the corrosion inhibitor needs to be increased in the cleaning process, so as to achieve better corrosion treatment effect of the electrical contact piece in the cleaning process.

[0067] The silver alloy sheet-shaped electrical contact piece treated above is measured by using the existing contact resistance test, the measurement method refers to GB / T 15078-2021, the four-terminal resistance measurement method is used to measure the contact resistance, the test is carried out under direct current condition, the current is 0.1 A, the open circuit voltage is 6 V, and the static contact pressure is 7 g. The contact resistance of the electrical contact piece is calculated by measuring the ratio of the voltage drop between the probe and the electrical contact piece to the loop current, and the specific calculation formula is as follows:

[0068] R=Delta(U) / I (6)

[0069] In the formula, R is the contact resistance, the unit is Ω; Delta(U) is the contact voltage drop value between the probe and the electrical contact piece, the unit is mV; I is the contact current, the unit is mA.

[0070] The actual measured and calculated contact resistance R=3.909x10 -2 Ω, compared with the predicted resistance value R c =40.84 mΩ of the application, the error value is 4.3%, the error is less than 5%, and the reliability is good.

[0071] It should be noted that in the process of the existing contact resistance test for the silver alloy sheet-shaped electric contact piece, in order to ensure the good contact of the four-terminal to the silver alloy sheet-shaped electric contact piece, a certain damage to the silver alloy sheet-shaped electric contact piece is inevitably caused, therefore, the existing contact resistance test is a destructive test, and the silver alloy sheet-shaped electric contact piece tested by the contact resistance test is greatly reduced in use reliability, and is usually scrapped or repaired after the test.

[0072] Example 2

[0073] In the front-end cleaning process cleaning liquid, 20 ppm of methyl imidazole is added as a corrosion inhibitor, and the silver alloy sheet-shaped electric contact piece after the cleaning process is detected, the contact is AgSnO2In2O3 contact, the diameter of the electric contact piece used is 4 mm, and the surface of the electric contact piece is characterized by using an ellipsometer (SENTECH, SEUV800, Germany), the instrument is equipped with a xenon lamp and a halogen lamp, the measurement range is 200~900 nm of 701 wavelength unit, and the organic protective film thickness d org of the surface of the electric contact piece is obtained in real time by ellipsometric spectroscopy ox =0.45 nm, R const =1.507 mΩ, R const =19.25 mΩ, R org =0.01 mΩ, and finally, by using the detection method of the present application, the predicted resistance value R ox =R c +R const +R org =20.77 mΩ, R ox <25 mΩ, and the electric contact piece is judged to be qualified. c

[0074] The above-mentioned treated contact is tested by using the existing contact resistance test, the test method is the same as that in Example 1, and the actual measured and calculated contact resistance R=1.896×10 -2 Ω, and compared with the predicted resistance value R c =20.77 mΩ of the present application, the error value is 8.71%, the error is less than 10%, and the reliability is good.

[0075] Example 3

[0076] ​In the front end of the cleaning process cleaning liquid added 40 ppm methyl imidazole as corrosion inhibitor, after the cleaning process of silver alloy sheet-shaped electric contact piece detection, contact is AgSnO2In2O3 contact, the diameter of the electric contact piece is 4 mm, the surface of the electric contact piece is characterized by an ellipsometer (SENTECH, SEUV800, Germany), which is equipped with a xenon lamp and a halogen lamp, the measurement range is 200~900 nm of 701 wavelength unit, the thickness of the organic protective film on the surface of the electric contact piece is obtained in real time by ellipsometry org =3.29nm, the thickness of the oxide film is d ox =0.29nm, R const The calculation is the same as in example 1, R const =1.507 mΩ, R org =20.43 mΩ, R ox =0.001 mΩ, finally, the detection method of the application can obtain the predicted resistance value R c =R const +R org +R ox =21.94 mΩ, R c <25 mΩ, it is judged that the electric contact piece is qualified.

[0077] The above treated contact is tested by the existing contact resistance test, the test method is the same as in example 1, the actual measurement and calculation of the contact resistance R=2.04×10 -2 Ω, compared with the predicted resistance value R c =21.94 mΩ of the application, the error value is 8.66%, the error is less than 10%, and the reliability is good.

[0078] Example 4

[0079] In the front end of the cleaning process cleaning liquid added 40 ppm methyl imidazole as corrosion inhibitor, after the cleaning process of silver alloy sheet-shaped electric contact piece detection, contact is AgSnO2In2O3 contact, the diameter of the electric contact piece is 4 mm, the thickness of the organic protective film on the surface of the electric contact piece is obtained in real time by ellipsometry org =4.46nm, the thickness of the oxide film is d ox =0.69nm, R const The calculation is the same as in example 1, R const =1.507 mΩ, R org =27.69 mΩ, R ox =0.12mΩ, finally, the detection method of the application can obtain the predicted resistance value R c =R const +Rorg +R ox =29.32 mΩ, R c > 25 mΩ, it is judged that the electrical contact piece is failure, and through the further judgment by the back-end processing flow, d3 is 3.5 nm, d org >d3, it is judged that the concentration of the corrosion inhibitor is too high, that is, when the concentration of the corrosion inhibitor is too high, the corrosion inhibitor exists local corrosion on the surface of the electrical contact piece in the cleaning process, and the concentration of the corrosion inhibitor added in the cleaning process needs to be reduced, so as to achieve the protection effect of the corrosion inhibitor film formed on the electrical contact piece in the cleaning process.

[0080] The above-processed contact is measured by using the existing contact resistance test, the test method is the same as that in Example 1, and the actual measured contact resistance R is 3.098*10 -2 Ω, compared with the predicted resistance value R c =29.33 mΩ of the application, the error value is -5.6%, the error is less than 10%, and the reliability is good.

[0081] Example 5

[0082] 80 ppm methyl imidazole is added as a corrosion inhibitor in the cleaning solution in the front-end cleaning process, and the silver alloy sheet-shaped electrical contact piece after the cleaning process is detected, the contact is AgSnO2In2O3 contact, the diameter of the electrical contact piece is 4 mm, an ellipsometer (SENTECH, SEUV800, Germany) is used to characterize the surface of the electrical contact piece, the instrument is equipped with a xenon lamp and a halogen lamp, the measurement range is 200~900 nm of 701 wavelength units, and the organic protective film thickness d org =4.76 nm of the surface of the electrical contact piece is obtained in real time by ellipsometric spectroscopy, the oxide film thickness is d ox =1.16 nm, R const is calculated, R const =1.507 mΩ is obtained, R org =29.56 mΩ is obtained, R ox =20.77 mΩ, as described above, the predicted resistance value R c =R const +R org +R ox =51.84 mΩ, R c > 25 mΩ, it is judged that the electrical contact piece is failure, and through the further judgment by the back-end processing flow, d1 is 1.0 nm, d ox >d1, d org>d3, determine as pickling insufficient, while judging as inhibitor concentration too high, in the case of inhibitor concentration too high, due to the inhibitor on the formation of the transition of the electric contact piece, corrosion protection, but not conducive to the removal of the surface of the electric contact piece in the cleaning process of the acidizing agent on the formation of the oxide film, therefore, in the case of high oxide film, resulting in electric contact piece failure. Need to reduce the concentration of the inhibitor or improve the concentration of the acidizing agent in the cleaning process, so as to achieve the effect of the cleaning process of the electric contact piece of the corrosion treatment.

[0083] The above-mentioned treated contact, using the existing contact resistance test, test method same as example 1, actual measurement and calculation of the contact resistance R = 5.321 x 10 -2 Ω, actual measurement and the predicted resistance value R c =51.84 mΩ compared to the error value 2.57%, the error is less than 10%, good reliability.

[0084] Compared with example 1, example 2~example 5, the oxide layer thickness d ox of the electric contact piece after the corrosion treatment of methyl imidazole is significantly reduced, wherein the electric contact piece corrosion effect of example 3 is best, d ox The oxide layer thickness of the electric contact piece of example 4 and example 5 is reduced by 76.23%, but when the concentration of the corrosion inhibitor is increased, the d ox oxide layer thickness of the electric contact piece is increased, which indicates that there is local corrosion on the surface of the electric contact piece, and the high concentration of the corrosion inhibitor will also affect the corrosion failure of the electric contact piece in the cleaning process.

[0085] The above examples only express the embodiment of the present application, which is described in detail and specifically, but it cannot be understood as the limitation of the scope of the present application. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, a number of variations and improvements can be made, which belong to the protection scope of the present application.

Claims

1. A method for detecting the failure of the corrosion protection of silver alloy sheet-like electrical contact pieces, characterized in that, The method comprises the following steps: S1: Real-time acquisition of the organic protective film thickness d on the surface of the electrical contact piece by means of ellipsometric spectroscopy org and the oxide film thickness d ox ; S2: the organic protective film thickness d org or the oxide film thickness d ox inputting a preset film thickness-contact resistance correlation model, and outputting a predicted contact resistance value R c ; S3: when the predicted contact resistance R c ≦ 25 mΩ, the electrical contact piece is determined to be qualified; when the predicted contact resistance R c > 25 mΩ, the electrical contact piece is determined to be failed, a back-end processing flow is triggered, and the front-end cleaning process is returned to. In step S3, the back-end processing flow is performed according to the following method: S4: When d ox d1, determine that pickling is insufficient; wherein d1 is an oxide film threshold value, in nm; S5: when d org< d2, determine that the inhibitor is ineffective, when d org > d3, determine that the inhibitor concentration is too high, wherein d2, d3 are organic film threshold values, in nm; The preset film thickness-contact resistance correlation model is constructed based on Holm contact theory and satisfies the following general form: R c = R const + R org + R ox (1) wherein: R const is the shrinkage resistance independent of the film layer, in units of mΩ; R org is the resistance function related to the thickness of the organic film, in units of mΩ; R ox is the resistance function related to the thickness of the oxide film, in units of mΩ.

2. The failure detection method for corrosion inhibition treatment of a silver alloy sheet-shaped electrical contact according to claim 1, wherein in formula (1), the R const , which is calculated as follows: R const = 500 x p x sqrt (π x H / F) (2) ρ is the resistivity of the electrical contact piece material, the unit is Ω·m, H is the hardness of the electrical contact piece material, the unit is Pa, and F is the contact pressure, the unit is N.

3. The method of claim 1, wherein R in (1) is the ratio of the area of the silver alloy sheet contact patch to the area of the silver alloy sheet contact patch at the end of the test. org which is calculated as follows: R org =ρ org ×d org ×10 -6 / A nom (3) p org is the organic film resistivity in Ω-m, d org is the organic film thickness in nm, A nom is the nominal contact area of the electrical contact piece in m 2 .

4. The method of claim 1, wherein R in (1) is the ratio of the area of the silver alloy sheet contact patch to the area of the silver alloy sheet contact patch at the end of the test. ox which is calculated as follows: R ox =h 2 ×d ox ×exp[4×π×d ox ×sqrt(2×m×Phi) / h] / [A nom ×e 2 ×sqrt(2×m×Phi)](4) Phi is the barrier height, the unit is ev, h is the Planck constant, m is the electron mass, and e is the electron charge.

5. A system for regulating the failure of silver alloy sheet electrical contact sheet corrosion mitigation treatment characterized by, The method comprises the following steps: The ellipsometric spectrum detection unit comprises a work station for positioning the electrical contact piece and a detection device for performing ellipsometric scanning on the work station, the detection device is electrically connected with a control mainboard, the control mainboard displays the thickness d of the organic protective film measured by the detection device in real time org and the thickness d of the oxide film ox The control mainboard transmits the thickness d of the organic protective film org and the thickness d of the oxide film ox to a lower processing unit. A resistance prediction unit, which is built-in with the preset film thickness-contact resistance correlation model, receives the organic protective film thickness d transmitted from the control mainboard org and the oxide film thickness d ox According to the preset film thickness-contact resistance correlation model, the R c =R const +R org +R ox predicted R c value is obtained, and the predicted R c value is transmitted to the next processing unit; a process decision unit receiving R c value transmitted from the resistance prediction unit, and transmitting an execution signal to a next process unit when the contact resistance R c > 25 mΩ is predicted. The actuator receives the execution signal from the process decision unit and sorts the unqualified electrical contact piece into the corresponding rework process tank.

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