Chromium plating electroplating process

Abstract

The invention relates to a chromium plating electroplating process which comprises the following steps: cleaning a plated part: cleaning floating dust and impurities on the surface layer of the plated part; a plating piece oil removal step: soaking the cleaned plating piece in oil removal liquid to remove oil on the surface layer of the plating piece; an oil removal liquid removal step: cleaning the oil removal liquid on the surface layer of the plated part after oil removal by using flowing clear water; pickling the plated part: soaking the cleaned plated part in a pickling solution to remove an oxide layer on the surface layer of the plated part; a pickling solution removal step: cleaning the pickling solution on the surface layer of the pickled plated part by using flowing clear water; electroplating a plating piece: placing the plating piece into the electroplating solution, and performing chromium electroplating under the current density of 20A / dm to 30A / dm; and a finished product air-drying step, wherein the electroplated finished product is blow-dried with hot air. According to the chromium plating electroplating process, a flat chromium plating layer can be blocked on the surface layer of the plating piece, and the requirement of special high-precision and advanced industries for high precision of the plating layer of the plating piece can be met.

Description

Technical Field

[0001] The invention relates to the field of chromium electroplating, in particular to a chromium electroplating process. Background Art

[0002] Electroplating is the process of plating a thin layer of other metals or alloys on certain metal surfaces using the principle of electrolysis. It is a process that uses electrolysis to attach a layer of metal film to the surface of metal or other material parts, thereby preventing the oxidation of the plated metal, improving the wear resistance, conductivity, reflectivity, corrosion resistance and aesthetics of the plated parts. The outer layer of many coins is also electroplated. During electroplating, the plating metal or other insoluble materials serve as the anode, and the workpiece to be plated serves as the cathode. The cations of the plating metal are reduced on the surface of the workpiece to be plated to form a plating layer. In order to eliminate the interference of other cations and make the plating uniform and firm, a solution containing the plating metal cations is used as the electroplating solution to keep the concentration of the plating metal cations unchanged. The purpose of electroplating is to plate a metal coating on the substrate to change the surface properties or size of the substrate.

[0003] However, chrome plating refers to the act of plating chrome as a coating on other metals. Chromium is a silvery-white metal with a slight bluish tint. Metallic chromium is very easy to passivate in the air, forming a very thin passivation film on the surface, thus showing the properties of precious metals. The chrome-plated layer has a very high hardness. The chrome-plated layer has good heat resistance. The chrome-plated layer has good wear resistance. In the traditional chrome plating process, the surface flatness of the chrome-plated layer is poor and cannot meet the high quality requirements. Summary of the invention

[0004] Based on this, it is necessary to provide a chrome electroplating process to address the technical problem that the surface flatness of the chrome plating layer is poor and cannot meet the high quality requirements of the traditional chrome plating process.

[0005] A chrome electroplating process, the process comprising the following steps: Plated parts cleaning steps: clean the dust and impurities on the surface of the plated parts; Plated parts degreasing steps: soak the cleaned plated parts in degreasing liquid to remove grease from the surface of the plated parts; Degreasing liquid removal steps: clean the degreasing liquid on the surface of the degreasing plated parts with running water; Pickling step for plated parts: soak the cleaned plated parts in pickling solution to remove the oxide layer on the surface of the plated parts; Pickling liquid removal step: clean the pickling liquid on the surface of the plated parts after pickling with running water; The plating step is as follows: placing the plated part in the plating solution, and electroplating chromium at a current density of 20A / dm to 30A / dm; Finished product air drying step: Dry the electroplated finished product with hot air.

[0006] In one of the embodiments, in the plated component cleaning step, an ultrasonic cleaning machine is used to clean the plated component.

[0007] In one of the embodiments, in the plated component cleaning step, the plated component is cleaned and the water on the surface is dried.

[0008] In one of the embodiments, in the degreasing liquid removal step, the plated parts are cleaned and then the water on the surface is dried.

[0009] In one of the embodiments, in the pickling solution removal step, the plated parts are cleaned and then the water on the surface is dried.

[0010] In one of the embodiments, in the step of electroplating the plated component, the temperature of the electroplating solution is 45 degrees Celsius to 55 degrees Celsius.

[0011] In one of the embodiments, in the step of electroplating the plated part, the electroplating solution includes 15g / L to 25g / L chromium sulfate, 10g / L to 20g / L chromium chloride, 10g / L to 15g / L potassium dihydrogen phosphate, 10g / L to 20g / L sodium dihydrogen phosphate, 5g / L to 10g / L sodium chloride, 5g / L to 10g / L sodium dodecyl sulfate, 6g / L to 10g / L propyl sulfonic acid, 3g / L to 5g / L sodium methylene disulfonate, 3g / L to 5g / L polyethyleneimine, 8g / L to 12g / L complexing agent, 1g / L to 2g / L stabilizer, 2g / L to 5g / L surfactant, and the solvent is water.

[0012] In one embodiment, the stabilizer is ammonium hydrochloride.

[0013] In one embodiment, the complexing agent is a mixture of propionic acid and acetic acid.

[0014] In one embodiment, the surfactant is a mixture of polyethylene glycol and polyvinyl alcohol.

[0015] The above-mentioned chrome plating electroplating process steps are concise and exquisite, easy to control, and each step is carefully and meticulously carried out. The dust and impurities on the surface of the plated part can be cleaned through the plated part cleaning step. The grease on the surface of the de-plated part can be cleaned through the plated part degreasing step. The oxide layer on the surface of the de-plated part can be cleaned through the degreasing liquid removal step. Thereby, the cleanliness of the surface of the plated part is ensured to increase the bonding force between the surface of the plated part and the coating. Through the plated part electroplating step, a dense, flat and firm chrome plating layer is plated on the surface of the plated part. The above-mentioned chrome plating electroplating process can form a flat chrome plating layer on the surface of the plated part, which can meet the high-precision requirements of special high-tech industries for plated parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1Schematic diagram of a chromium electroplating process in one embodiment. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0018] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0019] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0020] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0021] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0022] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0023] See also Figure 1 The present invention provides a chrome plating process, which comprises the following steps: Step 101: Plated component cleaning step: clean the dust and impurities on the surface of the plated component.

[0024] Specifically, the plated parts are first soaked in pure water for 20 to 30 minutes, and then cleaned with an ultrasonic cleaner to remove dust and impurities on the surface of the plated parts. After the plated parts are cleaned, the surface water is dried.

[0025] Step 102: Degreasing step of plated parts: soak the cleaned plated parts in degreasing liquid to remove grease from the surface of the plated parts.

[0026] Specifically, the cleaned plated parts are immersed in a degreasing solution to remove grease from the surface of the plated parts. Furthermore, the temperature of the degreasing solution is 50 degrees Celsius to 60 degrees Celsius, the immersion time is 1 minute to 1.5 minutes, and the plated parts are continuously shaken during the immersion process.

[0027] Step 103: Degreasing liquid removal step: Rinse the degreasing liquid on the surface of the degreasing plated parts with running water.

[0028] Specifically, a spray cleaning method is adopted to rinse the degreased plated parts with flowing pure water to remove the degreased liquid on the surface of the plated parts. After the degreased liquid on the plated parts is cleaned, the water on the surface is dried.

[0029] Step 104: Pickling of plated parts: Immerse the cleaned plated parts in a pickling solution to remove the oxide layer on the surface of the plated parts.

[0030] Specifically, the cleaned plated parts are immersed in a pickling solution to remove the oxide layer on the surface of the plated parts. Further, the temperature of the pickling solution is 45 degrees Celsius to 55 degrees Celsius, the immersion time is 1 minute to 1.5 minutes, and the plated parts are continuously shaken during the immersion process.

[0031] Step 105: Pickling liquid removal step: Use running water to clean the pickling liquid on the surface of the plated parts after pickling.

[0032] Specifically, the plated parts after pickling are rinsed with flowing pure water by spray cleaning, and the pickling liquid on the surface of the plated parts is cleaned. After the pickling liquid of the plated parts is cleaned, the water on the surface is dried.

[0033] Step 106: Part electroplating step: placing the part to be plated in the electroplating solution, and electroplating chromium at a current density of 20A / dm to 30A / dm.

[0034] Specifically, the plated part is placed in the electroplating solution, and chromium is electroplated at a current density of 20A / dm to 30A / dm. The temperature of the electroplating solution is 45 degrees Celsius to 55 degrees Celsius.

[0035] Step 107: Finished product air drying step: Dry the electroplated finished product with hot air.

[0036] Specifically, an industrial hair dryer is used to dry the electroplated finished product with hot air.

[0037] In order to increase the stability of the electroplating process and improve the flatness of the chrome-plated layer on the surface of the plated part, in one embodiment, in the plated part electroplating step, the electroplating solution includes 15g / L to 25g / L of chromium sulfate, 10g / L to 20g / L of chromium chloride, 10g / L to 15g / L of potassium dihydrogen phosphate, 10g / L to 20g / L of sodium dihydrogen phosphate, 5g / L to 10g / L of sodium chloride, 5g / L to 10g / L of sodium dodecyl sulfate, 6g / L to 10g / L of propyl sulfonic acid, 3g / L to 5g / L of sodium methylene disulfonate, 3g / L to 5g / L of polyethyleneimine, 8g / L to 12g / L of complexing agent, 1g / L to 2g / L of stabilizer, 2g / L to 5g / L of surfactant, and the solvent is water. Further, in another embodiment, the electroplating solution includes 18g / L to 22g / L chromium sulfate, 12g / L to 18g / L chromium chloride, 11g / L to 14g / L potassium dihydrogen phosphate, 12g / L to 18g / L sodium dihydrogen phosphate, 6g / L to 9g / L sodium chloride, 6g / L to 8g / L sodium dodecyl sulfate, 7g / L to 9g / L propyl sulfonic acid, 3.5g / L to 4.5g / L sodium methylene disulfonate, 3.5g / L to 4.5g / L polyethyleneimine, 9g / L to 11g / L complexing agent, 1.2g / L to 1.8g / L stabilizer, 3g / L to 4g / L surfactant, and the solvent is water. Specifically, in this embodiment, the electroplating solution includes 20 g / L chromium sulfate, 15 g / L chromium chloride, 12 g / L potassium dihydrogen phosphate, 15 g / L sodium dihydrogen phosphate, 8 g / L sodium chloride, 7 g / L sodium dodecyl sulfate, 8 g / L propyl sulfonic acid, 4 g / L sodium methylene disulfonate, 4 g / L polyethylene imine, 10 g / L complexing agent, 1.5 g / L stabilizer, 3.5 g / L surfactant, and the solvent is water. The electroplating solution composed of the above components can increase the stability of the electroplating process and improve the flatness of the chrome plating layer on the surface of the plated part.

[0038] In order to increase the stability of the electroplating process and ensure the stability of chromium ions in the electroplating solution, in one embodiment, the stabilizer is ammonium hydrogen hydrochloride, which can stabilize the trivalent chromium ions in the electroplating solution.

[0039] In order to increase the stability of the electroplating process and ensure the efficient conduct of the electroplating process, in one embodiment, the complexing agent is a mixture of propionic acid and acetic acid. The mixture of propionic acid and acetic acid can complex the trivalent chromium ions in the electroplating solution, greatly promote the cathode reduction reaction of the trivalent chromium complex ions, and thereby improve the stability of the plating solution.

[0040] In order to improve the efficiency of the electroplating process, in one embodiment, the surfactant is a mixture of polyethylene glycol and polyvinyl alcohol. The mixture of polyethylene glycol and polyvinyl alcohol can increase the efficiency of chrome plating on the surface of the plated part and increase the bonding stability between the chrome plating layer and the plated part. In this way, the efficiency of the electroplating process is improved.

[0041] The above-mentioned chrome plating electroplating process steps are concise and exquisite, easy to control, and each step is carefully and meticulously carried out. The dust and impurities on the surface of the plated part can be cleaned through the plated part cleaning step. The grease on the surface of the de-plated part can be cleaned through the plated part degreasing step. The oxide layer on the surface of the de-plated part can be cleaned through the degreasing liquid removal step. Thereby, the cleanliness of the surface of the plated part is ensured to increase the bonding force between the surface of the plated part and the coating. Through the plated part electroplating step, a dense, flat and firm chrome plating layer is plated on the surface of the plated part. The above-mentioned chrome plating electroplating process can form a flat chrome plating layer on the surface of the plated part, which can meet the high-precision requirements of special high-tech industries for plated parts.

[0042] In order to increase the degreasing efficiency of the surface of the plated component, in one embodiment, the degreasing liquid includes 20g / L to 40g / L of dodecyl dimethyl benzyl ammonium chloride, 11g / L to 23g / L of coconut oil diethanolamide, 40g / L to 60g / L of sodium hydroxide, 10g / L to 20g / L of sodium carbonate, 5g / L to 10g / L of sodium phosphate, 4g / L to 8g / L of sodium dodecyl sulfate, 4g / L to 10g / L of sodium silicate, and 6g / L to 12g / L of sodium sulfate, and the solvent is water. The degreasing liquid composed of the above components can efficiently remove grease from the surface of the plated component.

[0043] In order to increase the removal efficiency of the oxide layer on the surface of the plated part, in one embodiment, the pickling solution includes the following components by mass: 4 to 8 parts of nitric acid, 3 to 6 parts of hydrofluoric acid, 2 to 4 parts of hydrochloric acid, 3 to 5 parts of sulfuric acid, 1 to 3 parts of sodium sulfamate, 1 to 2 parts of sulfamic acid, and the balance is water. The pickling solution composed of the above components can efficiently remove the oxide layer on the surface of the plated part. The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0044] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A chrome plating process, characterized in that: The process comprises the following steps: Plated parts cleaning steps: clean the dust and impurities on the surface of the plated parts; Plated parts degreasing steps: soak the cleaned plated parts in degreasing liquid to remove grease from the surface of the plated parts; Degreasing liquid removal steps: clean the degreasing liquid on the surface of the degreasing plated parts with running water; Pickling step for plated parts: soak the cleaned plated parts in pickling solution to remove the oxide layer on the surface of the plated parts; Pickling liquid removal step: clean the pickling liquid on the surface of the plated parts after pickling with running water; The plating step is as follows: placing the plated part in the plating solution, and electroplating chromium at a current density of 20A / dm to 30A / dm; Finished product air drying step: Dry the electroplated finished product with hot air.

2. The process according to claim 1, characterized in that In the plated component cleaning step, an ultrasonic cleaning machine is used to clean the plated component.

3. The process according to claim 1, characterized in that In the plated part cleaning step, the plated part is cleaned and the water on the surface is dried.

4. The process according to claim 1, characterized in that In the degreasing liquid removal step, the plated parts are cleaned and the surface water is dried.

5. The process according to claim 1, characterized in that In the pickling solution removal step, the plated parts are cleaned and the surface water is dried.

6. The process according to claim 1, characterized in that In the step of electroplating the plated component, the temperature of the electroplating solution is 45 degrees Celsius to 55 degrees Celsius.

7. The process according to claim 1, characterized in that In the plated part electroplating step, the electroplating solution includes 15g / L to 25g / L chromium sulfate, 10g / L to 20g / L chromium chloride, 10g / L to 15g / L potassium dihydrogen phosphate, 10g / L to 20g / L sodium dihydrogen phosphate, 5g / L to 10g / L sodium chloride, 5g / L to 10g / L sodium dodecyl sulfate, 6g / L to 10g / L propyl sulfonic acid, 3g / L to 5g / L sodium methylene disulfonate, 3g / L to 5g / L polyethylene imine, 8g / L to 12g / L complexing agent, 1g / L to 2g / L stabilizer, 2g / L to 5g / L surfactant, and the solvent is water.

8. The process according to claim 7, characterized in that The stabilizer is ammonium hydrochloride.

9. The process according to claim 7, characterized in that The complexing agent is a mixture of propionic acid and acetic acid.

10. The process according to claim 7, characterized in that The surfactant is a mixture of polyethylene glycol and polyvinyl alcohol.

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