CN102002743A - Preparation method for electroplating thick tungsten coating on pure copper or copper alloy substrate with molten salt - Google Patents
Preparation method for electroplating thick tungsten coating on pure copper or copper alloy substrate with molten salt Download PDFInfo
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- CN102002743A CN102002743A CN 201010575369 CN201010575369A CN102002743A CN 102002743 A CN102002743 A CN 102002743A CN 201010575369 CN201010575369 CN 201010575369 CN 201010575369 A CN201010575369 A CN 201010575369A CN 102002743 A CN102002743 A CN 102002743A
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Abstract
The invention discloses a method for electroplating a thick tungsten coating on the substrate surface of pure copper or copper alloy with molten salt, belonging to the technical field of surface engineering. The method comprises the steps of: carrying out surface and drying process on electrodes, wherein the working electrode (substrate metal) is CuZrCr or oxygen-free copper (OF-Cu) or dispersion-strengthening copper alloy, and the counter electrode (anode) is pure metal tungsten piece; weighing the molten salt according to a certain molar ratio and drying, wherein the molten salt is Na2WO4-WO3 binary system; equally blending and heating to a molten state; connecting the cathode with the anode; and setting the current parameters and adjusting the electroplating time to obtain the metal tungsten coating with a needed thickness, wherein the current is unidirectional pulse current, the fixed mean current density is 100-150 mA/cm2, the pulse frequency is 10-1000 Hz, the duty ratio is 0.1-0.75, and the tungsten coating with a needed thickness of more than 1 mm is obtained through adjusting the electroplating time. The method for electroplating the thick tungsten coating on the substrate surface of pure copper or copper alloy iwith molten salt is suitable for the parts with abnormal shapes and has the advantages of: high density and high bonding strength of metal tungsten coating, simple processing equipment, convenient operation, low cost and no pollution.
Description
Technical field
The invention belongs to the Surface Engineering field, the method for a kind of fine copper or copper alloy matrix surface plating thick tungsten coating in molten salt bath particularly is provided.
Background technology
In the development of new forms of energy, material restricts one of its key of success factor often, as in the nuclear fusion energy towards plasma material (Plasma Facing Compoents, PFM); Target in the X-ray production apparatus; The throat liner material of solid propellant rocket trunnion; The materials such as transmitter of the probe in the microelectronic device, contact and motor car engine must have wear-resisting, performance such as anti-corrosion or anti-irradiation.Tungsten is owing to have high plasma resistant scouring capability, high-melting-point, boiling point, and high intensity, hardness, very little electron work functon and good chemical stability are considered to be applied in one of the candidate material of the best in these fields.But by the tungsten material that powder metallurgy is produced, very heavy and be difficult to processing, thereby to utilize coating technology to form tungsten coatings on other complicated structured materials surfaces are being good solutions.
The method for preparing at present tungsten coating on fine copper or copper alloy plate is a lot, as plasma spraying, and vapour deposition etc.Wherein electrochemical plating are a kind of traditional, effective meanss that obtain the tungsten coating, and contrast additive method, electrochemical plating equipment are to simply, and technology realizes being easier to.If choose suitable electrolyte in the plating, control current parameters and galvanized other external conditionss well just can to obtain fine and close pure metal tungsten from the oxide compound of tungsten and one step of salt, reduced the complex techniques process of preparation tungsten powder etc.In addition, reasonably coating process also will satisfy the various complicated shape requirements of part, and obviously, the fused salt electro-plating method can satisfy this requirement.
Because the current potential of tungsten is more negative than hydrogen, so being difficult in the aqueous solution, refractory metals tungsten obtains by electroplating, generally all adopt in melting salt, to electroplate to obtain tungsten.The oxide compound melting salt system of plated metal tungsten coating has Na at present
2WO
4-ZnO-WO
3But the ZnO in this system might influence tungsten and deposit on the matrix.Usually can destroy the quality of tungsten coating because electroplating parameter is set unreasonable or other uncontrollable factors make ZnO together deposit on the matrix as impurity and tungsten.
Summary of the invention
The invention provides a kind of Na
2WO
4-WO
3The preparation method of binary molten salt system fused salt plating thick tungsten coating on fine copper or copper alloy matrix, purpose overcome ZnO may together deposit on the matrix as impurity and tungsten, destroy the problem of the quality of tungsten coating.
This preparation method's molten salt system is Na
2WO
4-WO
3Wherein, WO
3Be the ion source of tungsten, Na
2WO
4Be solubility promoter.Fine copper or copper alloy are negative electrode, and pure metal tungsten sheet is an anode, while and WO
3Together also as the tungsten ion source.By adjusting the pure metal tungsten coating that current parameters and electroplating time obtain different thickness.Its concrete preparation process is:
The configuration of a, melting salt
Fused salt comprises Na
2WO
4And WO
3Two kinds of components, two kinds of component concentrations according to molar percentage are: Na
2WO
4: WO
3=5: 2.Fused salt is pressed the dehydration of component weighing after drying.
B, electrode surface pre-treatment
Fine copper or copper alloy are as negative electrode, and pure metal tungsten all will be earlier through strict surface treatment, to remove adherent filth and surperficial grease as anode.Be specially earlier through mechanical grinding polishing, acetone ultrasonic cleaning and deionized water ultrasonic cleaning then, final drying.
C, plating
Na
2WO
4300 ℃ of dryings 10~20 hours, WO
3100 ℃ of dryings 10~20 hours.Evenly mixed to the fused salt handled well, be heated to 850 ℃~920 ℃ in the electrolyzer of packing into, the ionic constituent that is incubated then to the fused salt is stable.Connect negative electrode and anode this moment, set current parameters and begin to electroplate.
D, plating piece are handled
Plating piece after plating finished takes out from fused salt, put into 5~30% NaOH solution rapidly washing the fused salt that adheres to, and coating is carried out quench treatment, and then use acetone and deionized water ultrasonic cleaning respectively, thoroughly to remove the dirt settling on the plating piece, obtain the thick tungsten coating material.
Described current parameters is that electric current adopts unidirectional pulse electric current or periodic reverse electric current respectively; The fixed current density that wherein adopts the unidirectional pulse electric current is at 30~120mA/cm
2, pulse-repetition is 100~1000Hz, and dutycycle is 0.1~0.75, and electroplating time is 10~20 hours; The fixed current density that adopts the periodic reverse electric current is at 30~120mA/cm
2, pulse-repetition is 100~1000Hz, electroplating time is 10~20 hours.
The diffusion layer thickness that described thick tungsten coating material is negative electrode and tungsten is 0.01-0.05mm, and the pure tungsten coat-thickness is 1.0-2.0mm.
Above-mentioned operation is all carried out under air atmosphere, and operating equipment is simple, and cost is low, easily realizes.
Above-mentioned tungsten ion source is WO
3With the tungsten positive plate.
Na
2WO
4-WO
3Thereby the binary molten salt system has been owing to removed the appearance that ZnO has avoided this problem, makes electroplating parameter easier control, and quality of coating also is greatly improved.At Na
2WO
4-WO
3Adopt pulsive electroplating to prepare the tungsten coating in the binary molten salt system, need to set the suitable current parameter, after fused salt is heated to certain temperature negative electrode and anode are connected, be immersed in the fused salt, pass to electric current obtains different thickness by the adjustment of electroplating time tungsten coating then.Because existing thermodiffusion has cathode overpotential again in melting salt, makes that the bonding force of tungsten coating and matrix is very high, good compactness is applicable to irregular part.
The invention has the advantages that:
1, at Na
2WO
4-WO
3Electroplate tungsten in the melting salt system, the coating densification that obtains, the formation of tungsten coating is to make tungsten forming core and growing up on matrix because impressed current forms cathode overpotential, also can further form one deck diffusion layer between tungsten coating and matrix owing to thermodiffusion makes simultaneously, increase bonding strength.
2, by adopting unidirectional pulse or reverse pulse electric current all can obtain the pure metal tungsten coating, by adjusting the coating that electroplating time can obtain controllable thickness.This just makes the performance of tungsten coating and thickness control current parameters outward by groove fully and realizes.
3, can handle the workpiece of complicated shapes such as curved surface, endoporus.
4, processing unit is simple, and is easy to operate, with low cost, pollution-free.
Embodiment
Matrix (negative electrode): CuCrZr alloy (oxygen free copper or dispersion strengthening copper alloy)
Supporting electrode (anode): tungsten
Implementation step:
Embodiment 1:
1, molten salt electrolyte is according to molar percentage weighing: Na
2WO
4: WO
3=5: 2; Na
2WO
4300 ℃ of drying and dehydratings 10 hours, WO
3100 ℃ of dryings 10 hours, mix then.
2, negative electrode CuCrZr alloy and anode tungsten sheet carry out mechanical grinding, polishing respectively, remove the greasy dirt and the dirt settling on surface then respectively in 8 minutes with acetone and deionized water ultrasonic cleaning.
3, the melting salt of mixing is put into electrolyzer and be warmed up to 850 ℃, then constant temperature for some time, make the fused salt ionic constituent stable.
4, connect negative electrode plating piece and anode tungsten sheet, earlier with 40mA/cm
2Pre-the plating 20 minutes of reverse direct current, adopt 120mA/cm then
2The unidirectional pulse electric current carry out plating, pulse-repetition 1000Hz, dutycycle is 0.1, electroplating time 10 hours.
5, the plating piece that plating is finished takes out the dirt settling of putting into 5%NaOH solution flush away surface rapidly.
Embodiment 2:
1, molten salt electrolyte is according to molar percentage weighing: Na
2WO
4: WO
3=5: 2; Na
2WO
4300 ℃ of drying and dehydratings 15 hours, WO
3100 ℃ of dryings 15 hours, mix then.
2, negative electrode CuCrZr alloy and anode tungsten sheet carry out mechanical grinding, polishing respectively, remove the greasy dirt and the dirt settling on surface then respectively in 8 minutes with acetone and deionized water ultrasonic cleaning.
3, the melting salt of mixing is put into electrolyzer and be warming up to 900 ℃, then constant temperature for some time, make the fused salt ionic constituent stable.
4, connect negative electrode plating piece and anode tungsten sheet, earlier with 40mA/cm
2Pre-the plating 20 minutes of reverse direct current, adopt 60mA/cm then
2Pulsed current carry out plating, pulse-repetition 100Hz, dutycycle 0.25, electroplating time 15 hours.
5, the plating piece that plating is finished takes out the dirt settling of putting into 10%NaOH solution flush away surface rapidly.
Embodiment 3:
1, molten salt electrolyte is according to molar percentage weighing: Na
2WO
4: WO
3=5: 2; Na
2WO
4300 ℃ of drying and dehydratings 20 hours, WO
3100 ℃ of dryings 20 hours, mix then.
2, negative electrode CuCrZr alloy and anode tungsten sheet carry out mechanical grinding, polishing respectively, remove the greasy dirt and the dirt settling on surface then respectively in 8 minutes with acetone and deionized water ultrasonic cleaning.
3, the melting salt of mixing is put into electrolyzer and be warming up to 920 ℃, then constant temperature for some time, make the fused salt ionic constituent stable.
4, connect negative electrode plating piece and anode tungsten sheet, earlier with 40mA/cm
2Pre-the plating 20 minutes of reverse direct current, adopt 30mA/cm then
2Pulsed current carry out plating, pulse-repetition 1000Hz, dutycycle 0.75, electroplating time 20 hours.
5, the plating piece that plating is finished takes out the dirt settling of putting into 15%NaOH solution flush away surface rapidly.
Embodiment 4:
1, molten salt electrolyte is according to molar percentage weighing: Na
2WO
4: WO
3=5: 2; Na
2WO
4300 ℃ of drying and dehydratings 10 hours, WO
3100 ℃ of dryings 10 hours, mix then.
2, negative electrode CuCrZr alloy and anode tungsten sheet carry out mechanical grinding, polishing respectively, remove the greasy dirt and the dirt settling on surface then respectively in 8 minutes with acetone and deionized water ultrasonic cleaning.
3, the melting salt of mixing is put into electrolyzer and be warming up to 850 ℃, then constant temperature for some time, make the fused salt ionic constituent stable.
4, connect negative electrode plating piece and anode tungsten sheet,, earlier with 40mA/cm
2Pre-the plating 20 minutes of reverse direct current, adopt forward current density 120mA/cm then
2Periodic reverse electric current (forward and reverse time ratio 4: 1, forward and reverse current density ratio 6: 1), pulse-repetition 1000Hz, electroplating time 10 hours.
5, the plating piece that plating is finished takes out rapidly the dirt settling of putting into 20% NaOH solution flush away surface.
Embodiment 5:
1, molten salt electrolyte is according to molar percentage weighing: Na
2WO
4: WO
3=5: 2; Na
2WO
4300 ℃ of drying and dehydratings 15 hours, WO
3100 ℃ of dryings 15 hours, mix then.
2, negative electrode CuCrZr alloy and anode tungsten sheet carry out mechanical grinding, polishing respectively, remove the greasy dirt and the dirt settling on surface then respectively in 8 minutes with acetone and deionized water ultrasonic cleaning.
3, the melting salt of mixing is put into electrolyzer and be warming up to 900 ℃, then constant temperature for some time, make the fused salt ionic constituent stable.
4, connect negative electrode plating piece and anode tungsten sheet, earlier with 40mA/cm
2Pre-the plating 20 minutes of reverse direct current, adopt forward current density 60mA/cm then
2Periodic reverse electric current (forward and reverse time ratio 4: 1, forward and reverse current density ratio 6: 1), pulse-repetition 100Hz, electroplating time 15 hours.
5, the plating piece that plating is finished takes out rapidly the dirt settling of putting into 25% NaOH solution flush away surface.
Embodiment 6:
1, molten salt electrolyte is according to molar percentage weighing: Na
2WO
4: WO
3=5: 2; Na
2WO
4300 ℃ of drying and dehydratings 20 hours, WO
3100 ℃ of dryings 20 hours, mix then.
2, negative electrode CuCrZr alloy and anode tungsten sheet carry out mechanical grinding, polishing respectively, remove the greasy dirt and the dirt settling on surface then respectively in 8 minutes with acetone and deionized water ultrasonic cleaning.
3, the melting salt of mixing is put into electrolyzer and be warming up to 920 ℃, then constant temperature for some time, make the fused salt ionic constituent stable.
4, connect negative electrode plating piece and anode tungsten sheet,, earlier with 40mA/cm
2Pre-the plating 20 minutes of reverse direct current, adopt forward current density 30mA/cm then
2Periodic reverse electric current (forward and reverse time ratio 4: 1, forward and reverse current density ratio 6: 1), pulse-repetition 1000Hz, electroplating time 20 hours.
5, the plating piece that plating is finished takes out rapidly the dirt settling of putting into 30% NaOH solution flush away surface.
Claims (5)
1. the preparation method of fused salt plating thick tungsten coating on fine copper or copper alloy matrix, it is characterized in that: preparation method's step is divided into configuration, electrode surface pre-treatment, plating, the plating piece of melting salt and handles four steps; Concrete steps are:
The configuration of a, melting salt
The melting salt composition comprises Na
2WO
4And WO
3, each component concentration by mole per-cent is: Na
2WO
4: WO
3=5: 2, WO wherein
3Be the ion source of tungsten, Na
2WO
4Be solubility promoter;
B, electrode surface pre-treatment
Fine copper or copper alloy plating piece are as negative electrode, and pure metal tungsten is as anode; Negative electrode and anode will pass through mechanical grinding, polishing, ultrasonic cleaning and drying treatment; Anticathode and anode carry out dimensional measurement and weight weighing before the plating;
C, plating
With Na
2WO
4300 ℃ of dryings 10~20 hours to take off crystal water, with WO
3100 ℃ of dryings 10~20 hours; With blended Na
2WO
4-WO
3Melting salt rises to 850 ℃~920 ℃ with stable heat-up rate and forms fused salt, is incubated to molten salt system to stablize, and connects negative electrode and anode, connects power supply, sets electroplating parameter, the beginning plating;
D, plating piece are handled
Plating piece after plating finished takes out, and removes the dirt settling on the plating piece; Obtain the thick tungsten coating material.
2. as claimed in claim 1 on fine copper or copper alloy matrix the preparation method of fused salt plating thick tungsten coating, it is characterized in that: described ultrasonic cleaning comprises acetone ultrasonic cleaning and two stages of deionized water ultrasonic cleaning.
3. as claimed in claim 1 on fine copper or copper alloy matrix the preparation method of fused salt plating thick tungsten coating, it is characterized in that: described electroplating parameter is that electric current adopts unidirectional pulse electric current or periodic reverse electric current respectively; The fixed current density that wherein adopts the unidirectional pulse electric current is at 30~120mA/cm
2, pulse-repetition is 100~1000Hz, and dutycycle is 0.1~0.75, and electroplating time is 10~20 hours; The fixed current density that adopts the periodic reverse electric current is at 30~120mA/cm
2, pulse-repetition is 100~1000Hz, electroplating time is 10~20 hours.
4. as claimed in claim 1 on fine copper or copper alloy matrix the preparation method of fused salt plating thick tungsten coating, it is characterized in that: diffusion layer thickness 0.01~0.05mm that described thick tungsten coating material is negative electrode and tungsten, the pure tungsten coat-thickness is 1.0~2.0mm.
5. as claimed in claim 1 on fine copper or copper alloy matrix the preparation method of fused salt plating thick tungsten coating, it is characterized in that: after the plating piece after plating is finished takes out, put into 5~30% NaOH solution to wash the fused salt that adheres to, and coating carried out quench treatment, and then use acetone and deionized water ultrasonic cleaning respectively, remove the dirt settling on the plating piece; Obtain the thick tungsten coating material.
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Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105200471A (en) * | 2015-10-28 | 2015-12-30 | 南京信息工程大学 | Method for pulse inversion electrodeposition of thick tungsten coating layer |
CN107201537A (en) * | 2017-05-19 | 2017-09-26 | 北京科技大学 | A kind of of the same race or different alloys connection methods |
CN110528033A (en) * | 2019-08-19 | 2019-12-03 | 北京工业大学 | The method that a kind of electro-deposition of fused salt original position prepares tungsten coating |
CN116103603A (en) * | 2020-11-04 | 2023-05-12 | 苏州热工研究院有限公司 | Preparation method of gamma ray shielding coating |
CN118492594A (en) * | 2024-07-18 | 2024-08-16 | 吉林大学 | Method for prolonging service life of end face of aluminum alloy resistance spot welding electrode |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0280589A (en) * | 1988-09-17 | 1990-03-20 | Nisshin Steel Co Ltd | Tungsten electroplating bath and plating method using the bath |
-
2010
- 2010-12-01 CN CN2010105753697A patent/CN102002743B/en not_active Expired - Fee Related
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0280589A (en) * | 1988-09-17 | 1990-03-20 | Nisshin Steel Co Ltd | Tungsten electroplating bath and plating method using the bath |
Non-Patent Citations (2)
Title |
---|
《中国有色金属学报》 20001031 马瑞新等 Na2WO4-WO3-ZnO体系熔盐镀钨 715-718 1-5 第10卷, 第5期 2 * |
《材料保护》 19991231 马瑞新等 熔盐镀钨的历史与发展趋势 1-7 1-5 第32卷, 第2期 2 * |
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105200471A (en) * | 2015-10-28 | 2015-12-30 | 南京信息工程大学 | Method for pulse inversion electrodeposition of thick tungsten coating layer |
CN107201537A (en) * | 2017-05-19 | 2017-09-26 | 北京科技大学 | A kind of of the same race or different alloys connection methods |
CN107201537B (en) * | 2017-05-19 | 2019-11-12 | 北京科技大学 | A kind of of the same race or different alloys connection methods |
CN110528033A (en) * | 2019-08-19 | 2019-12-03 | 北京工业大学 | The method that a kind of electro-deposition of fused salt original position prepares tungsten coating |
CN110528033B (en) * | 2019-08-19 | 2020-11-10 | 北京工业大学 | Method for preparing tungsten coating by fused salt in-situ electrodeposition |
CN116103603A (en) * | 2020-11-04 | 2023-05-12 | 苏州热工研究院有限公司 | Preparation method of gamma ray shielding coating |
CN118492594A (en) * | 2024-07-18 | 2024-08-16 | 吉林大学 | Method for prolonging service life of end face of aluminum alloy resistance spot welding electrode |
CN118492594B (en) * | 2024-07-18 | 2024-09-24 | 吉林大学 | Method for prolonging service life of end face of aluminum alloy resistance spot welding electrode |
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