GB/T 17848-1999 Test method for electrochemical performance of sacrificial anode
Some standard content:
1cs 47. 020. 05
National Standard of the People's Republic of China
GB/T 17848—1999
Test methods for electrochemical propertiesof sacrificial anodes
1999-08-31 Issued
2000-06-01 Implementation
National Quality and Technical Supervision Bureau Issued
CB/T17848—1999Www.bzxZ.net
This standard specifies the conventional test method and the added test method for testing the electrochemical performance of sacrificial anodes of zinc alloys, aluminum alloys, and steel alloys. The strip test method is based on the long-term use and research of CE/T4918—1985 "Sacrificial Anode Constant Current Electrochemical Performance Test Method for Sacrificial Anodes" Appendix C of Aluminum-Zinc-Steel Alloy Sacrificial Anodes and GB/T1950—1985 "Sacrificial Anode Electrochemical Performance Test Method for Lead-Acid Alloy Sacrificial Anodes (Constant Current Method)". The accelerated test method is equivalent to the characteristic anode electrochemical performance test method in the Norwegian Shipbuilding Association (DNV) RP1491 "Catheter Protection Design" .
Compared with Appendix C in GB/T4948-1985 and Appendix C in GB/T4950-1985, this standard adds the electrochemical performance test method of the sacrificial anode of the lock alloy and the accelerated test method of the electrochemical performance of the sacrificial anode of the aluminum, zinc and magnesium alloys, and supplements Appendix A and Appendix B.
This standard will replace Appendix C of GB/T1948-1985 and Appendix B of GB/T1948-1985 from the date of implementation. Appendix A of this standard and Appendix 13 are both indicative appendices. This standard was proposed by China State Shipbuilding Corporation and is under the jurisdiction of Luoyang Ship Material Research Institute of China State Shipbuilding Corporation. The drafting unit of this standard: Luoyang Ship Material Research Institute of China State Shipbuilding Corporation. The main drafters of this standard: Chen Xuli, Hao Jianhua, Wen Xiuzuo, Zhu Yunlong. 1 Scope
National Standard of the People's Republic of China
Test methodsfor electrochemical preperliesof suerificial anndes
GB/T 178481999
This standard specifies the whole process of testing the electrochemical performance of sacrificial anodes by using the tape test method and the galvanometer test method, test preparation, test operation, test procedure and the method of expressing the test results. This standard is applicable to testing the electrochemical performance of zinc alloy, aluminum alloy and magnesium alloy sacrificial electrodes in seawater, as well as testing the electrochemical performance of sacrificial anodes in simulated environments. It can also be used for testing the electrochemical performance of other types of sacrificial anodes. 2 Classification of test methods
2.1 Common test method
During the specified test period, a constant current is passed through the sample, and the upper and lower currents of the anode sample are measured every two hours. At the end of the test, the actual capacitance and current efficiency of the sample are calculated, and the electrochemical state of the anode sample is observed. The tape test method is used to accurately measure the electrochemical performance of sacrificial electrodes.
2.2 Accelerated test method
In the specified test cycle, change the liquid concentration of the closed electrode sample according to the following sequence. Select the maximum potential of the over-electrode sample, and plot the actual capacitance and current efficiency of the old electrode sample, and measure the dissolution of the anode sample, and test the additional anode product. When the anode sample is new, the test method is repeated. 3 Test equipment
The micro-anode electrochemical performance test equipment mainly consists of auxiliary anode, test container, adjustable voltage, DC current meter, power meter, power supply, voltage meter, and integral ratio electrode. The circuit diagram of the test equipment is shown in Figure 1. The test container or test chamber 3 three-phase circuit limit: 1 The circuit design is carried out according to the circuit design!
6 Power source? ·Current positive table: Test equipment selection test equipment distance diagram
National Quality and Technical Supervision Bureau 1999-D8-31 approved 2000-06-01 implementation
3.1 Auxiliary electrodes
GB/T17848-1999
Auxiliary cathode plate is made of ordinary carbon steel or stainless steel. The inside and outside are both industrial surfaces. The total area is about 840cm. 3.2
Test penetrator
The size of the test container should be able to make the anode sample and the auxiliary cathode completely immersed in the test medium. It is recommended to use a 5000 mL glass ceramic ring.
Adjustable resistor
Adjustable resistor should use a decade resistor box with a resistance value of not less than 11.11 kΩ. 3.4 DC ammeter
The DC ammeter shall be a bypass meter with a rated current higher than 0.5. 3.5 Power supply
A true current source shall be used, and the rated output current shall not be less than 60 mA, and the rated output voltage shall not be less than 40 V. If a current source with a differential of 1/3 is used, the adjustable resistor, DC ammeter, and electricity meter may not be used. 3.6 Voltage meter
Alternatively, a steel meter or an electronic meter may be used. The preparation method of the steel voltmeter is shown in Appendix A (prompt recording). The accuracy of the electricity meter shall not be less than (.5%) of the full range. 3.7 Current and voltmeter
The input impedance shall be greater than 10 M8, and the minimum scale shall be 1 mV or more digital voltmeter or high-precision potentiometer, 3.8 Reference electrode
Use insulated and sheet mercury electrodes.
Preparation of anode sample
Anode sample is processed into a round shape. It can be used in Figure 2 a) and b) two structures and specifications. Each group of tests requires three test samples. 4.1
Anode sample structure diagram
4.2 The anode sample is cleaned with distilled water, and then cleaned with propane or light ethanol. 4.3 Bake in an oven at 105℃=2℃ for 30 tnin, take it out and put it in a dryer. 4.4 After the anode sample is cooled to room temperature, it is weighed for the first time; then the baking and weighing procedures are repeated. The difference between the two weighing results is no more than 2
GB/T178481999
0.1mg, and the average of the two weighings is taken as the weight of the anode sample. If the difference between the two weighing results is greater than 0.411%, a third baking and weighing should be carried out, and the half-average of the two closest weighing results should be taken as the weight of the anode sample. The weighing is carried out using a bridge balance with a minimum graduation value of 0.1 m.
4.5 If the test uses a power meter, the cathode copper sheet of the copper meter should be treated according to the methods specified in 4.2 to 4.4, and the anode steel sheet should be disinfected and dried.
4.6 The non-working surface of the anode sample and the water-immersed part connected to the copper should be sealed with highly insulating materials. The working area of the anode sample is 11 The rtm anode sample is sealed and the gap between the working surfaces is formed to avoid pore corrosion. 5 Test conditions
5.1 Test medium
When used in seawater environment, the test medium of zinc alloy, lead alloy and iron alloy anode samples is artificial seawater or clean natural seawater.
When used in environment, the test medium of magnesium alloy anode samples is artificial seawater saturated with Mg(OH) or clean natural water saturated with Mg(OH).
5.2 Mixing temperature
The medium temperature is 15~30℃.
5.3 Weak position of auxiliary cathode and anode samples
The auxiliary cathode is fixed at a position more than 10-mm above the water surface and the bottom surface, and the anode plate is suspended in the center of the cathode ring. 6 Test procedure
6.1 After the test device is connected, it is ready for use. 6.2 After the aluminum anode sample has been in the medium for 3 lh, the open circuit potential of the anode sample is measured. After the zinc and magnesium anode samples have been in the medium for 1 h, the open circuit potential of the cathode sample is measured. 6.3 Power on and adjust the adjustable resistor to keep the anode current density at the specified value in Table 1. Table 1: Current density range Conventional test method Test time, b Current width mA/cm 1nA/cm Constant specific current Test time, h n-24 2>2--48>48-72≥72~96 Accelerated test Current density +mA/cm 6.4 Measure the L potential of the anode sample with high rate. When measuring the base, the salt-corrected end of the reference electrode should be as close to the surface of the anode sample as possible. 6.5 The test cycle of the conventional test method is 210 hours, and the test cycle of the accelerated test method is 96 hours. 6.6 Soak the electrode sample in a chemical agent such as xylene to remove the coating: Clean the cathode steel sheet of the copper electrometer with distilled water. 6.7 After removing the coating seal, the corrosion products on the surface of the anode sample should be chemically treated. The treatment method is shown in Table 2. Table 2 Treatment methods for corrosion products of anode sample Name of anode sample
Lead alloy
Front alloy anode
Magnesium alloy
Other product treatment methods
Soak in 68% concentrated rubbing acid for 5 ~ 10 min, rinse with water, and soak in ammonium acetate for 2 ~ 31, use a wool to gently remove the corrosion products until the selected products are completely removed, then rinse with water, soak in 20% Cr03O3 at 60-80°C for 10 min, or control in 20% Ct0-free liquid at room temperature for 30 min, then rinse with water
GB/T 178481999
6.8 Bake and weigh the treated anode sample and the exhausted cathode copper sheet according to the requirements of 1.3 ~ 4.5, 7 7.1 Graphs and tables 7.1.1 Tabulate the open circuit potential of the anode sample. 7.1.2 Tabulate the working potential of the anode sample during the test or draw a potential-time curve of the anode sample. 7.1.3 Record the morphological characteristics of the surface flow fast state and the ionization products of the anode sample. 7.2 Calculation 7.2.1 Calculation of actual capacitance a) When the current through the plate sample is measured by a copper electrometer, the actual capacitance of the closed-electrode sample shall be calculated according to the formula (1): Q = k × (M, -MP/(m, -
Where: Q is the actual capacitance of the conductive anode sample, A·h/kg; coefficient k = 843.3, A + h/kg F
M, - the weight of the weak electrode steel sheet in the test, g;
The weight of the cathode steel sheet after the test + the weight of the anode sample before the test +
m2 --- the weight of the anode sample after the test, g. (b) When the current through the anode sample is measured by an electronic electrometer, the actual capacitance of the anode sample shall be calculated according to the formula (2): Q = k × (M, -MP/(m, -
Where: Q is the actual capacitance of the conductive anode sample, A·h/kg; coefficient k = 843.3, A + h/kg F
M, - the weight of the weak electrode steel sheet in the test, g;
The weight of the cathode steel sheet after the test + the weight of the anode sample before the test +
m2 --- the weight of the anode sample after the test, g. -m,)
Actual capacitance of sacrificial anode sample, A·h/kg: Where: Q
…-The amount of electricity passed by the sacrificial anode sample during the test cycle, A·hAnode test weight before the test, 8:
Weight of sacrificial anode sample after the test, %
7.2.2 Calculation of current efficiency
a) Calculate the theoretical capacitance of the sacrificial anode according to the main components of the alloy according to formula (3): Q,-AX-+-B.Y+C.Z+*
Q. ——Theoretical capacitance of sacrificial anode, A·h/kgt Where:
ABC-Proportion of alloy components, %,
Theoretical capacitance of alloy components, A·h/kg: XY, z
b) Calculate the current efficiency of the sacrificial anode sample according to formula (1): (%) = (Q/Q) × 100
Electrolysis efficiency of the special anode, %:
8 Precautions
8.1 Prevent chemical reagents from harming the human body
When preparing the electrolysis reagent and cleaning the anode sample, the operator should take protective measures for the eyes, skin and other parts exposed to the outside.
8.2 Prevent harmful gases from harming human health
The chemical disinfection of the sealing material and the anode corrosion product with monomethyl foam should be carried out in a ventilated cabinet. 8.3 Prevent chemical liquid from polluting the environment
Handling the chemical liquid after the anode sample is used should be handled according to the relevant provisions of the national environmental protection laws and regulations. 4
A1 Electrode material, shape and cathode current density GB/T 17848 --1999
Appendix A
(Reminder)
Preparation method of copper coulometer
The electrode material of short-circuit current meter is selected from electrolytic electrolyte with purity not less than 99.95%. The shape of the electrode is also selected in the form of a plate. The cathode current density is 2-2 A/t.*.
A2 Arrangement of electrodes and container
There is no electrode in the two anodes, and the cathode, that is, the distance between the two electrodes is 0.0~], and the container is made of plastic or plastic, with a capacity of more than 100 ml. and is sealed. A3
Composition of electrolyte
Prepare 1 L of electrolyte. See Table A1 for the composition of electrolyte. All components are analytical grade chemical reagents. Chemical composition of electrolyte
(uS) -SH.O
IL.S(),(μ1. X4 μ/mL)
<:,H.0H(1D0%)
Treatment of cathode copper sheet before and after test
Before the test, the cathode surface is polished with sandpaper, cleaned with alcohol or acetone, dried and weighed. The cathode should also be cleaned and dried. Take the cathode from the electrolyte and wash it with distilled water, ethanol or acetone, dry it for 1 hour, and weigh it. Appendix B (Tyre's Appendix) Preparation of human body water B1 Preparation of solution No. 1 The components in Table B1 are dissolved in water or distilled water with analytical grade reagents. The total amount is diluted to 7.0:1 with distilled water. Then, the mixture is sealed and stored in a sealed container. The chemical warfare agent of the solution No. Mgt'l·alo
Srl: + [,o
B2 Preparation of solution No. 2 GB/T 17848—1999
The components in B2 are dissolved in stagnant water or steamed water with analytical grade reagents according to the specified solution, and the total dilution is 7.01. Then pour into brown water and seal it for storage.
Table 132
Chemical composition of dissolved N2
B3 Preparation of artificial seawater
The method for preparing 10.0L artificial seawater is as follows: First, dissolve 245.34 NaCl and 4(,94 Va2SCO) to 8.0~9. 0L distilled water. Then slowly add 200mL of paint solution No.1 and 100mL of solution No.2, and stir thoroughly. Dilute the total amount to 10.0L with distilled water. Finally, adjust the pH value of artificial seawater to 8.2 with 0.1mol/L NaOH solution. B4 Chemical composition of artificial seawater
The chemical composition of artificial seawater is shown in Table B3,
Table B3 Chemical composition of artificial seawater
Tension·R/L
NaHcoa
Cat lg)
Actual capacitance of sacrificial anode sample, A·h/kg: Where: Q
…-the amount of electricity passed through the sacrificial anode sample during the test cycle, A·h; Anode test weight before test, 8:
Weight of sacrificial anode sample after test, %
7.2.2 Calculation of current efficiency
a) Calculate the theoretical capacitance of the sacrificial anode according to the main components of the alloy using formula (3): Q, -AX-+-B.Y+C.Z+*
Q. ——Theoretical capacitance of the sacrificial anode, A·h/kgt Where:
ABC- alloy composition ratio, %,
Theoretical capacitance of alloy composition, A·h/kg: XY, z
b) Calculate the current efficiency of the sacrificial anode sample according to formula (1): (%) = (Q/Q) × 100
The electrolytic efficiency of the sacrificial anode, %:
8 Precautions
8.1 Prevent chemical reagents from harming the human body
When preparing the electrochemical reagent and cleaning the anode sample, the operator should take protective measures for the exposed parts of the eyes, skin, etc.
8.2 Prevent harmful gases from harming human health
The chemical decontamination of the anode corrosion products with monomethyl foam should be carried out in a ventilated cabinet. 8.3 Preventing the environment from being polluted by chemical liquid
Handling the chemical liquid after the use of the anode sample should be handled in accordance with the relevant provisions of the national environmental protection laws and regulations. 4
A1 Electrode material, shape and cathode current density GB/T 17848-1999
Appendix A
(Reminder)
Preparation method of copper coulometer
The electrode material of the short-circuit meter is selected from electrolytic electrolyte with a purity of not less than 99.95%: the shape is also selected as a plate. The cathode current band is 2-2 A/t.*.
A2 Arrangement of electrodes and container
There is no electrode in the two anodes, that is, the distance between the cathodes is 0.0~], and the container is made of plastic or plastic, and its capacity is above 100 ml., and it is sealed. A3
Composition of electrolyte
Prepare 1 L. The composition of electrolyte is shown in Table A1. All components are analytical grade chemical reagents. Chemical composition of electrolyte
(uS) -SH.O
IL.S(),(μ1. X4 μ/mL)
<:,H.0H(1D0%)
Treatment of cathode copper sheet before and after test
Before the test, the cathode surface is polished with sandpaper, cleaned with alcohol or acetone, dried and weighed. The cathode juice should also be cleaned and dried. Take the cathode from the electrolyte and wash it with distilled water, ethanol or acetone, dry it for 1 hour, and weigh it. Appendix B (Tyre's Appendix) Preparation of human remains sea water B1 Preparation solution No. 1 The components in Table B1 are dissolved in water or distilled water with analytical grade reagents. The total amount is diluted to 7.0:1 with distilled water. Then, the mixture is sealed and stored in a sealed container. The chemical warfare agent of the solution No. Mgt'l·alo
Srl: + [,o
B2 Preparation solution No. 2 GB/T 17848—1999
The components in B2 are dissolved in stagnant water or steamed water with analytical grade reagents according to the specified solution, and the total dilution is 7.01. Then pour into brown water and seal it for storage.
Table 132
Chemical composition of dissolved N2
B3 Preparation of artificial seawater
The method for preparing 10.0L artificial seawater is as follows: First, dissolve 245.34 NaCl and 4(,94 Va2SCO) to 8.0~9. 0L distilled water. Then slowly add 200mL of paint solution No.1 and 100mL of solution No.2, and stir thoroughly. Dilute the total amount to 10.0L with distilled water. Finally, adjust the pH value of artificial seawater to 8.2 with 0.1mol/L NaOH solution. B4 Chemical composition of artificial seawater
The chemical composition of artificial seawater is shown in Table B3,
Table B3 Chemical composition of artificial seawater
Tension·R/L
NaHcoa
Cat lg)
Actual capacitance of sacrificial anode sample, A·h/kg: Where: Q
…-the amount of electricity passed through the sacrificial anode sample during the test cycle, A·h; Anode test weight before test, 8:
Weight of sacrificial anode sample after test, %
7.2.2 Calculation of current efficiency
a) Calculate the theoretical capacitance of the sacrificial anode according to the main components of the alloy using formula (3): Q, -AX-+-B.Y+C.Z+*
Q. ——Theoretical capacitance of the sacrificial anode, A·h/kgt Where:
ABC- alloy composition ratio, %,
Theoretical capacitance of alloy composition, A·h/kg: XY, z
b) Calculate the current efficiency of the sacrificial anode sample according to formula (1): (%) = (Q/Q) × 100
The electrolytic efficiency of the sacrificial anode, %:
8 Precautions
8.1 Prevent chemical reagents from harming the human body
When preparing the electrochemical reagent and cleaning the anode sample, the operator should take protective measures for the exposed parts of the eyes, skin, etc.
8.2 Prevent harmful gases from harming human health
The chemical decontamination of the anode corrosion products with monomethyl foam should be carried out in a ventilated cabinet. 8.3 Preventing the environment from being polluted by chemical liquid
Handling the chemical liquid after the use of the anode sample should be handled in accordance with the relevant provisions of the national environmental protection laws and regulations. 4
A1 Electrode material, shape and cathode current density GB/T 17848-1999
Appendix A
(Reminder)
Preparation method of copper coulometer
The electrode material of the short-circuit meter is selected from electrolytic electrolyte with a purity of not less than 99.95%: the shape is also selected as a plate. The cathode current band is 2-2 A/t.*.
A2 Arrangement of electrodes and container
There is no electrode in the two anodes, that is, the distance between the cathodes is 0.0~], and the container is made of plastic or plastic, and its capacity is above 100 ml., and it is sealed. A3
Composition of electrolyte
Prepare 1 L. The composition of electrolyte is shown in Table A1. All components are analytical grade chemical reagents. Chemical composition of electrolyte
(uS) -SH.O
IL.S(),(μ1. X4 μ/mL)
<:,H.0H(1D0%)
Treatment of cathode copper sheet before and after test
Before the test, the cathode surface is polished with sandpaper, cleaned with alcohol or acetone, dried and weighed. The cathode juice should also be cleaned and dried. Take the cathode from the electrolyte and wash it with distilled water, ethanol or acetone, dry it for 1 hour, and weigh it. Appendix B (Tyre's Appendix) Preparation of human remains sea water B1 Preparation solution No. 1 The components in Table B1 are dissolved in water or distilled water with analytical grade reagents. The total amount is diluted to 7.0:1 with distilled water. Then, the mixture is sealed and stored in a sealed container. The chemical warfare agent of the solution No. Mgt'l·alo
Srl: + [,o
B2 Preparation solution No. 2 GB/T 17848—1999
The components in B2 are dissolved in stagnant water or steamed water with analytical grade reagents according to the specified solution, and the total dilution is 7.01. Then pour into brown water and seal it for storage.
Table 132
Chemical composition of dissolved N2
B3 Preparation of artificial seawater
The method for preparing 10.0L artificial seawater is as follows: First, dissolve 245.34 NaCl and 4(,94 Va2SCO) to 8.0~9. 0L distilled water. Then slowly add 200mL of paint solution No.1 and 100mL of solution No.2, and stir thoroughly. Dilute the total amount to 10.0L with distilled water. Finally, adjust the pH value of artificial seawater to 8.2 with 0.1mol/L NaOH solution. B4 Chemical composition of artificial seawater
The chemical composition of artificial seawater is shown in Table B3,
Table B3 Chemical composition of artificial seawater
Tension·R/L
NaHcoa
Cat lg
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