Hardware surface treatment process

Abstract

The invention discloses a hardware surface treatment process. The hardware surface treatment process comprises the steps that firstly, the surface of hardware is cleaned, and a pre-plating layer with the thickness of 0.01-0.05 micrometer is formed; then, the pre-plating layer is subjected to micro-crystallization treatment and annealed under the protective atmosphere, so that internal stress is released; next, a hard chromium layer is electroplated on the annealed hardware, the current density is controlled not to exceed 200 amperes per square meter, and uniform deposition is ensured; the hard chromium layer is polished after electroplating, and a nanoscale oxide coating is applied to enhance the binding force with the base material; then the surface of the hard chromium layer is subjected to vibration treatment for 5 minutes through ultrasonic waves with the frequency of 20-50 kHz, and interface stress is eliminated; and finally, the surface of the hardware is coated with an organic silicon resin protective film, curing is conducted for at least one hour at the temperature of 100-150 DEG C, and the additional stress buffering effect is provided. By means of the steps, the internal stress between the base material and the hard chromium plating layer is effectively controlled, cracks are reduced, meanwhile, the abrasion resistance and corrosion resistance of the plating layer are enhanced, and the service life of the hardware is prolonged.

Description

Technical Field

[0001] The invention belongs to the technical field of hardware processing, and in particular relates to a hardware surface treatment process. Background Art

[0002] In modern manufacturing, surface treatment of hardware is a crucial process, especially for those parts that need to have high wear resistance and corrosion resistance. Hard chrome plating has become one of the commonly used surface treatment technologies due to its excellent physical properties. Hard chrome plating has good hardness, wear resistance and corrosion resistance, and is widely used in automobile manufacturing, aerospace, precision machinery and other industries.

[0003] The existing hard chrome electroplating process mainly includes basic steps such as cleaning the substrate and electroplating the hard chrome layer. However, in actual applications, it is found that although the hard chrome plating provides a good protective effect, the plating may still crack or peel under some extreme conditions of use, such as high friction load or strong corrosion environment. These problems are mainly attributed to the internal stress between the substrate and the plating. When this stress exceeds a certain limit, it will lead to the failure of the plating.

[0004] In the existing hard chrome electroplating process, how to effectively control the stress between the substrate and the coating and reduce the occurrence of cracks is one of the key issues that need to be solved. Although many methods have been tried to improve this situation, such as improving the coating quality by optimizing the electroplating parameters, the defects caused by stress have not been completely avoided. Summary of the invention

[0005] The purpose of the present invention is to provide a hardware surface treatment process, which not only enhances the bonding strength between the coating and the substrate by adding a nano-scale oxide coating and a silicone resin protective film, but also further improves the wear resistance and corrosion resistance of the hardware surface, so as to solve the problems raised in the above-mentioned background technology.

[0006] To achieve the above object, the present invention adopts the following technical solution: a surface treatment process for hardware, comprising the following steps:

[0007] S1: After cleaning the surface of the hardware and removing oil and impurities, a pre-plating layer is formed on the surface of the hardware, and the thickness of the pre-plating layer is controlled within the range of 0.01 to 0.05 microns;

[0008] S2: performing microcrystallization treatment on the formed pre-plating layer to refine the crystal structure of the pre-plating layer, performing an intermediate annealing process, heating to 350 to 450 degrees Celsius under a protective atmosphere, and maintaining for 30 minutes to release the internal stress of the pre-plating layer;

[0009] S3: Electroplating a hard chrome layer on the annealed hardware, during which the current density is controlled not to exceed 200 amperes per square meter, so that the hard chrome layer is deposited evenly;

[0010] S4: After the electroplating is completed, the hard chromium layer is surface polished, and a layer of nano-scale oxide coating is applied to the polished hard chromium layer to enhance the bonding force between the hard chromium layer and the substrate;

[0011] S5: After the oxide coating is completed, the surface of the hard chrome layer is treated with ultrasonic vibration, with the frequency set between 20 kHz and 50 kHz and the vibration time being 5 minutes to eliminate the interface stress;

[0012] S6: Coat a layer of silicone resin protective film on the surface of the hardware after ultrasonic treatment, set the curing temperature at 100 to 150 degrees Celsius, and the curing time is not less than 1 hour to provide additional stress buffering effect.

[0013] Preferably, cleaning the surface of the hardware includes the following sub-steps: using a non-ionic surfactant to prepare a 1% aqueous solution to soak the hardware for 10-15 minutes, and then manually scrubbing the surface of the hardware with a soft brush; rinsing the hardware with running water to remove the residual active agent and loose impurities on the surface. After rinsing, the hardware is placed in an oven at a temperature of 60-65 degrees Celsius to dry for 30-35 minutes; using a dust-free cloth dipped in isopropyl alcohol to wipe the surface of the hardware to finally remove fine particles.

[0014] Preferably, forming a pre-plating layer on the surface of the hardware includes the following sub-steps: immersing the cleaned hardware in an electrolyte containing nickel salt as an anode, maintaining the electrolyte temperature at 40-45 degrees Celsius, applying a constant current density of 0.5 amperes per square decimeter, and setting the continuous electroplating time to 5-7 minutes; then using deionized water to thoroughly rinse the hardware to prevent electrolyte residue from affecting subsequent processes; after rinsing, placing the hardware in a ventilated place to dry naturally, ready to enter the next process.

[0015] Preferably, the microcrystallization treatment of the formed pre-plating layer includes the following sub-steps: placing the formed pre-plating hardware into a microcrystallization bath containing sodium dodecyl sulfate and urea, and maintaining the bath temperature at 30-35 degrees Celsius; applying a pulse current to the hardware, with the frequency set to 50 Hz, the current density being 1 ampere per square decimeter, and the treatment time being 2 minutes; after completion, immediately removing the hardware from the bath; after removal, immediately rinsing the hardware with pure water to remove surface residues; placing the hardware in a dry environment to air dry, ensuring that the surface is completely dry so as to proceed to the next step.

[0016] Preferably, the intermediate annealing process includes the following sub-steps: placing the hardware that has completed the microcrystallization treatment into a furnace preheated to 350 degrees Celsius, gradually increasing the furnace temperature to 400 degrees Celsius, and ensuring that the furnace is an inert gas environment; when the specified temperature is reached, maintaining this temperature for 30 minutes, during which the inert gas atmosphere is maintained unchanged, after the insulation period, cooling to room temperature with the furnace, after cooling is completed, taking the hardware out of the furnace and preparing to enter the subsequent processing stage.

[0017] Preferably, electroplating a hard chromium layer on the annealed hardware includes the following sub-steps: preparing an electroplating solution containing chromic acid and adjusting the pH value to between 4.5 and 5.0, using the annealed hardware as a cathode and immersing it in the electroplating solution prepared in the first sub-step; turning on the DC power supply, setting the current density to 180 amperes per square meter, and continuing the electroplating for 20-22 minutes; during the electroplating period, continuously stirring the electroplating solution to ensure that the hard chromium layer is evenly deposited on the surface of the hardware, and after the electroplating is completed, turning off the power supply, taking out the hardware and rinsing it thoroughly with deionized water.

[0018] Preferably, the surface polishing of the hard chrome layer includes the following sub-steps: using a 1000-mesh abrasive paste to evenly apply it on the surface of the electroplated hard chrome layer, and using a polishing machine with a rotation speed of 1000 revolutions per minute and a wool wheel to polish the hardware for 5-7 minutes; after completion, checking the surface of the hard chrome layer to confirm that the micro-roughness has been improved; then, thoroughly cleaning the surface of the hardware with a high-pressure water spray gun to remove all abrasive paste residues, and after cleaning, wiping the hardware with a clean lint-free cloth to ensure that there are no water stains and other contaminants on the surface.

[0019] Preferably, applying a layer of nano-scale oxide coating to the polished hard chromium layer includes the following sub-steps: placing the polished hardware in a vacuum coating chamber, evacuating the chamber, and introducing aluminum metal vapor into the coating chamber; depositing a layer of aluminum oxide film with a thickness of about 50 nanometers on the surface of the hard chromium layer by electron beam evaporation, and after the deposition process is completed, gradually restoring the pressure in the coating chamber to normal pressure; taking out the hardware, checking whether the coating evenly covers the surface of the hard chromium layer, and confirming that it is well bonded to the substrate.

[0020] Preferably, the use of ultrasonic vibration to treat the surface of the hard chrome layer includes the following sub-steps: placing the hardware after applying a layer of nano-scale oxide coating on an ultrasonic vibration table, starting the ultrasonic device, and adjusting the frequency to 30 kHz; after the frequency is set, starting the vibration treatment, and setting the duration to 5 minutes. During the vibration treatment, monitor the working state of the vibration table to ensure that the frequency is stable and the hardware remains motionless; after the end, turn off the ultrasonic device, take out the hardware, and check whether there are signs of stress release on the surface.

[0021] Preferably, coating a layer of silicone resin protective film on the surface of the hardware after ultrasonic treatment includes the following sub-steps: uniformly spraying a layer of silicone resin solution on the surface of the hardware after ultrasonic treatment; after spraying, leaving the hardware to stand for 10-15 minutes to allow the silicone resin to initially solidify, and during the standing period, preparing an oven and preheating it to 120 degrees Celsius; placing the hardware that has been left to stand in the preheated oven and starting the curing treatment, the curing time is not less than 1 hour, so that the silicone resin is fully cured.

[0022] Technical effects and advantages of the present invention: Compared with the prior art, the surface treatment process of hardware proposed by the present invention has the following advantages:

[0023] The present invention effectively controls the internal stress between the substrate and the hard chrome plating layer by microcrystallizing the pre-plating layer and annealing it in a protective atmosphere, thereby reducing the generation of cracks. In addition, by adding a nano-scale oxide coating and an organic silicone resin protective film, not only the bonding force between the plating layer and the substrate is enhanced, but also the wear resistance and corrosion resistance of the surface of the hardware are further improved, thereby extending the service life of the hardware. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The present invention is a flow chart of a hardware surface treatment process. DETAILED DESCRIPTION

[0025] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. The specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0026] The present invention provides a hardware surface treatment process, such as Figure 1 As shown, the following steps are included:

[0027] S1: After cleaning the surface of the hardware and removing oil and impurities, a pre-plating layer is formed on the surface of the hardware, and the thickness of the pre-plating layer is controlled within the range of 0.01 to 0.05 microns;

[0028] Further cleaning of the hardware surface includes the following sub-steps:

[0029] Soaking treatment: Use a non-ionic surfactant to prepare a 1% aqueous solution, immerse the hardware completely in the solution, and set the soaking time to 10 to 15 minutes to ensure that oil stains and impurities are fully dissolved.

[0030] Manual scrubbing: After soaking, use a soft-bristled brush to manually scrub the surface of the hardware, especially for grooves and hard-to-reach areas, which need to be cleaned carefully to ensure that there is no residual dirt on the surface.

[0031] Rinse with running water: After brushing, use running water to thoroughly rinse the hardware to remove residual surfactants and loose impurities on the surface to ensure that the surface is clean and free of residue.

[0032] Drying: After rinsing, place the hardware in an oven at 60 to 65 degrees Celsius and set the drying time to 30 to 35 minutes to ensure that the surface of the hardware is completely dry.

[0033] Isopropyl alcohol wiping: After drying, use a dust-free cloth to dip in an appropriate amount of isopropyl alcohol and carefully wipe the surface of the hardware to remove any small particles and prepare for subsequent processes.

[0034] Furthermore, forming a pre-plating layer on the surface of the hardware comprises the following sub-steps:

[0035] Immerse in electrolyte: Immerse the cleaned hardware through the above steps in an electrolyte containing nickel salt as an anode. The electrolyte temperature is maintained at 40 to 45 degrees Celsius to maintain the stability of the electrolyte and the activity of the metal ions.

[0036] Apply current: Apply a constant current density of 0.5 amperes per square decimeter to the hardware immersed in the electrolyte, and set the continuous electroplating time to 5 to 7 minutes to ensure that the pre-plating layer is evenly deposited and the thickness is controlled within the range of 0.01 to 0.05 microns.

[0037] Rinse to remove residue: After electroplating is completed, immediately rinse the hardware thoroughly with deionized water to prevent electrolyte residue from adversely affecting subsequent processes.

[0038] Natural drying: After rinsing, place the hardware in a well-ventilated place to dry naturally, ready for the next process.

[0039] Through the above steps, the hardware surface treatment process provided by the present invention can effectively remove oil stains and impurities on the surface of the hardware, and form a uniform and thin pre-plating layer on the surface thereof, which not only helps the hard chromium electroplating layer in the subsequent process to adhere better, but also through fine cleaning and pre-plating treatment, significantly reduces the internal stress between the hard chromium layer and the substrate, thereby effectively preventing the occurrence of cracks and peeling.

[0040] In addition, the present invention enhances the bonding force between the hard chromium layer and the substrate by controlling the thickness and uniformity of the pre-plating layer, further improves the wear resistance and corrosion resistance of the surface of the hardware, and prolongs the service life of the hardware.

[0041] S2: performing microcrystallization treatment on the formed pre-plating layer to refine the crystal structure of the pre-plating layer, performing an intermediate annealing process, heating to 350 to 450 degrees Celsius under a protective atmosphere, and maintaining for 30 minutes to release the internal stress of the pre-plating layer;

[0042] Further microcrystallization of the formed pre-plating layer includes the following sub-steps:

[0043] Immerse in microcrystallization bath: Place the hardware that has been treated in the first step and has a pre-plated layer into a microcrystallization bath containing sodium dodecyl sulfate and urea. The bath temperature is maintained at 30 to 35 degrees Celsius to promote the refinement of the crystal structure of the pre-plated layer.

[0044] Applying pulse current: Based on the first sub-step, a pulse current with a frequency of 50 Hz and a current density of 1 ampere per square decimeter is applied to the hardware for a processing time of 2 minutes to refine the crystal structure of the pre-plating layer.

[0045] Removing the Hardware: After the second sub-step is completed, remove the hardware from the bath immediately to avoid prolonged contact with the bath solution that may lead to excessive handling.

[0046] Rinse the hardware: After taking it out, immediately rinse the hardware with pure water to remove the bath liquid components remaining on the surface.

[0047] Air dry: After rinsing, place the hardware in a dry environment to air dry, ensuring that the surface is completely dry so that you can proceed to the next step.

[0048] The further implementation of the intermediate annealing process comprises the following sub-steps:

[0049] Put into the furnace: Place the hardware that has completed the microcrystallization treatment into the furnace preheated to 350 degrees Celsius.

[0050] Heating treatment: gradually increase the furnace temperature to 400 degrees Celsius and ensure that the furnace is in an inert gas environment to prevent oxidation reactions.

[0051] Heat preservation treatment: When the furnace temperature reaches 400 degrees Celsius, maintain this temperature for 30 minutes, during which time the inert gas atmosphere is maintained unchanged to release the stress in the pre-plating layer.

[0052] Cooling with the furnace: After the insulation period, cool to room temperature with the furnace to avoid new stress caused by rapid cooling.

[0053] Through the above steps, the hardware surface treatment process provided by the present invention can effectively refine the crystal structure of the pre-plating layer, and enhance the compactness and uniformity of the coating. The microcrystallization treatment makes the crystals of the pre-plating layer finer, and improves the overall performance of the coating. The subsequent intermediate annealing process effectively releases the residual stress in the pre-plating layer by heating and keeping warm under a protective atmosphere, and reduces cracks and peeling caused by excessive stress.

[0054] The entire process not only improves the bonding strength between the hard chrome plating and the substrate, but also significantly enhances the wear resistance and corrosion resistance of the hardware surface, thereby extending the service life of the hardware.

[0055] S3: electroplating a hard chrome layer on the annealed hardware, controlling the current density to not exceed 200 amperes per square meter during the electroplating process, so that the hard chrome layer is uniformly deposited; further comprising the following sub-steps:

[0056] Prepare the plating solution: Prepare a plating solution containing chromic acid and adjust the pH value to between 4.5 and 5.0 to ensure that the solution is in the best state for plating.

[0057] Immerse the hardware: Use the annealed hardware as the cathode and immerse it in the prepared electroplating solution, making sure the hardware is completely immersed in the solution.

[0058] Turn on the power supply for electroplating: Turn on the DC power supply, set the current density to 180 amperes per square meter, and continue the electroplating time for 20 to 22 minutes to ensure that the hard chrome layer can be evenly deposited on the surface of the hardware.

[0059] Stirring the solution: During the entire electroplating period, the electroplating solution is continuously stirred to ensure that the chromic acid in the solution is evenly distributed, avoiding local concentrations that are too high or too low, thereby ensuring the uniformity of the hard chromium layer on the surface of the hardware.

[0060] Remove the hardware: After the electroplating is completed, turn off the power, immediately remove the hardware from the electroplating solution, and immediately rinse the surface of the hardware thoroughly with deionized water to remove all residual electroplating solution to prevent corrosion or other adverse reactions in subsequent processes.

[0061] Natural drying: After rinsing, place the hardware in a well-ventilated environment to dry naturally and prepare for the next process.

[0062] Through the above steps, the hardware surface treatment process provided by the present invention forms a uniform and dense hard chromium layer on the surface of the hardware after annealing. By strictly controlling the current density during the electroplating process to not exceed 200 amperes per square meter and maintaining it at 180 amperes per square meter, the uniform deposition of the hard chromium layer on the surface of the hardware is ensured, avoiding the problem of inconsistent performance caused by local excessive thickness or excessive thinness.

[0063] In addition, the operation of continuously stirring the electroplating solution further ensures the uniformity of the hard chrome layer and enhances the bonding force between the plating layer and the substrate. After such treatment, the hard chrome layer not only has excellent wear resistance and corrosion resistance, but also can effectively resist the influence of the external environment, greatly extending the service life of the hardware. At the same time, the uniform hard chrome layer can also reduce cracks and peeling caused by stress concentration, improving the overall quality and reliability of the hardware.

[0064] S4: After the electroplating is completed, the hard chromium layer is surface polished, and a layer of nano-scale oxide coating is applied to the polished hard chromium layer to enhance the bonding force between the hard chromium layer and the substrate;

[0065] Further surface polishing of the hard chrome layer includes the following sub-steps:

[0066] Apply abrasive paste: Use a 1000 mesh abrasive paste and apply it evenly on the surface of the hard chrome layer after electroplating to ensure that the entire surface is evenly covered.

[0067] Polishing: Use a polishing machine with a rotation speed of 1000 revolutions per minute and a wool wheel to polish the hardware. The duration is set to 5 to 7 minutes to ensure that the micro-roughness of the surface of the hard chrome layer is effectively improved.

[0068] Check the surface: After polishing, check the surface of the hard chrome layer to confirm that the micro-roughness has been improved and the surface is smooth and scratch-free.

[0069] Cleaning hardware: Use a high-pressure water spray gun to thoroughly clean the surface of the hardware to remove all abrasive paste residue and ensure that the surface is clean and free of contamination.

[0070] Dry the hardware: After cleaning, use a clean, lint-free cloth to dry the hardware to ensure that there is no water stains and other contaminants on the surface, ready for the next step.

[0071] Further applying a nano-scale oxide coating to the polished hard chrome layer comprises the following sub-steps:

[0072] Prepare the coating chamber: Place the polished hardware in the vacuum coating chamber and evacuate to the desired pressure level.

[0073] Introducing Aluminum Metal Vapor: Introducing aluminum metal vapor into the coating chamber in preparation for oxide coating deposition.

[0074] Deposition of oxide coating: A layer of aluminum oxide (Al2O3) film with a thickness of about 50 nanometers is deposited on the surface of the hard chrome layer by electron beam evaporation to ensure that the coating evenly covers the surface of the hard chrome layer.

[0075] Restoring to normal pressure: After the deposition process is completed, gradually restore the coating chamber to normal pressure to avoid the impact of sudden pressure changes on the coating.

[0076] Check the coating: Take out the hardware and check whether the coating evenly covers the surface of the hard chrome layer, confirm that it is well bonded to the substrate, and there are no obvious defects or unevenness.

[0077] Through the above steps, the hardware surface treatment process provided by the present invention can effectively improve the microscopic roughness of the hard chrome layer surface, making the surface smoother and improving the appearance quality and touch of the hardware. The polishing treatment not only removes the microscopic unevenness of the surface, but also provides a better adhesion basis for the subsequent oxide coating.

[0078] The application of nano-scale oxide coating further enhances the bonding force between the hard chrome layer and the substrate, and improves the wear resistance and corrosion resistance of the coating. The Al2O3 coating has excellent chemical stability and mechanical strength, which can effectively resist the erosion of the external environment, while also reducing the stress between the hard chrome layer and the substrate, reducing the risk of cracks and peeling.

[0079] Overall, this process not only improves the aesthetics and functionality of the hardware surface, but also significantly extends the service life of the hardware, making it suitable for a variety of high-demand application scenarios.

[0080] S5: After the oxide coating is completed, the surface of the hard chrome layer is treated by ultrasonic vibration, the frequency is set between 20 kHz and 50 kHz, the vibration time is 5 minutes, and the interface stress is eliminated; further comprising the following sub-steps:

[0081] Place the hardware: Place the hardware treated with nano-oxide coating steadily on the ultrasonic vibration table to ensure that the hardware is stable and does not move.

[0082] Start the ultrasonic device: Start the ultrasonic device and adjust the frequency to 30 kHz, which is the best frequency range selected based on experimental data and can effectively transfer energy to the surface of the hard chrome layer.

[0083] Start vibration treatment: After the frequency setting is completed, start the vibration treatment and set the duration to 5 minutes. During this period, it is necessary to closely monitor the working status of the vibration table to ensure that the frequency is stable and the hardware remains motionless during the entire treatment process to avoid position displacement due to vibration.

[0084] Check the treatment effect: After the vibration treatment is completed, turn off the ultrasonic device and carefully remove the hardware. Check whether there are signs of stress release on the surface of the hard chrome layer, such as reduced or disappeared cracks, smoother surface, etc.

[0085] Record results: Record the inspection results to ensure that the vibration treatment has achieved the desired effect, that is, effectively eliminate the stress at the interface between the hard chrome layer and the substrate.

[0086] Through the above steps, the hardware surface treatment process provided by the present invention utilizes ultrasonic vibration treatment to effectively eliminate the stress at the interface between the hard chrome layer and the substrate. Ultrasonic vibration treatment transfers energy to the surface of the hard chrome layer through high-frequency vibration, so that the microscopic defects inside the hard chrome layer are alleviated, thereby reducing the interface stress and reducing the risk of cracks and peeling.

[0087] Specifically, the frequency of ultrasonic vibration treatment is set at 30 kHz and the duration is 5 minutes. This parameter setting can ensure that the energy is evenly transferred to the surface of the hard chrome layer and promote the uniform release of stress. At the same time, the working status of the vibration table is monitored during the vibration treatment process to ensure the consistency and effectiveness of the treatment and avoid poor treatment results due to equipment failure or improper operation.

[0088] After ultrasonic vibration treatment, the bonding force between the hard chrome layer and the substrate is significantly enhanced, and the surface quality is improved. This not only improves the wear resistance and corrosion resistance of the hardware, but also further extends the service life of the hardware.

[0089] S6: Coating a layer of silicone resin protective film on the surface of the hardware after ultrasonic treatment, with the curing temperature set at 100 to 150 degrees Celsius and the curing time not less than 1 hour to provide additional stress buffering effect. Further comprising the following sub-steps:

[0090] Spraying silicone resin solution: Spray a layer of silicone resin solution evenly on the surface of the ultrasonically treated hardware. Ensure that the spraying is even and covers the entire hard chrome layer surface to avoid missing or uneven spraying.

[0091] After spraying, let the hardware stand for 10 to 15 minutes to allow the silicone resin to solidify. During this period, the silicone resin will begin to solidify and form a stable film.

[0092] Prepare the oven: During the rest period, prepare the oven and preheat it to 120 degrees C. Make sure the oven temperature is evenly distributed to ensure a consistent cure.

[0093] Curing treatment: Place the hardware that has been left to stand in an oven preheated to 120 degrees Celsius to start the curing treatment. The curing time should be no less than 1 hour to ensure that the silicone resin is fully cured and forms a solid and uniform protective film.

[0094] Remove the hardware: After curing is completed, turn off the oven power, wait for the oven temperature to drop to a safe temperature, and carefully remove the hardware. Check whether the silicone resin protective film is evenly covered on the surface of the hard chrome layer, and confirm that it is tightly combined with the hard chrome layer without blistering or peeling.

[0095] Final inspection: Conduct a comprehensive inspection on the cured hardware to ensure that the surface is flat and flawless, there is no obvious boundary between the silicone resin protective film and the hard chrome layer, and the overall bonding is in good condition.

[0096] Through the above steps, the hardware surface treatment process provided by the present invention coats a layer of silicone resin protective film on the surface of the hard chrome layer after ultrasonic treatment, and ensures the full curing of the protective film through high temperature curing. This process step not only further enhances the bonding force between the hard chrome layer and the substrate, but also provides an additional stress buffering effect, significantly improving the wear resistance and corrosion resistance of the hardware surface.

[0097] Specifically, the silicone resin protective film has excellent weather resistance and chemical stability, and can effectively resist the erosion of the external environment. The cured silicone resin protective film forms a uniform and tight film covering the surface of the hard chrome layer, which not only enhances the smoothness of the surface, but also reduces the stress concentration between the hard chrome layer and the substrate, reducing the risk of cracks and peeling.

[0098] In addition, by curing at 120 degrees Celsius for no less than 1 hour, the silicone resin is fully cross-linked and cured to form a stable and durable protective layer. This not only improves the surface quality of the hardware, but also significantly extends the service life of the hardware, making it perform well in various complex working environments and suitable for industrial applications with high requirements for surface performance.

[0099] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A hardware surface treatment process, characterized in that: The following steps are involved: S1: After cleaning the surface of the hardware and removing oil and impurities, a pre-plating layer is formed on the surface of the hardware, and the thickness of the pre-plating layer is controlled within the range of 0.01 to 0.05 microns; S2: performing microcrystallization treatment on the formed pre-plating layer to refine the crystal structure of the pre-plating layer, performing an intermediate annealing process, heating to 350 to 450 degrees Celsius under a protective atmosphere, and maintaining for 30 minutes to release the internal stress of the pre-plating layer; S3: Electroplating a hard chrome layer on the annealed hardware, during which the current density is controlled not to exceed 200 amperes per square meter, so that the hard chrome layer is deposited evenly; S4: After the electroplating is completed, the hard chromium layer is surface polished, and a layer of nano-scale oxide coating is applied to the polished hard chromium layer to enhance the bonding force between the hard chromium layer and the substrate; S5: After the oxide coating is completed, the surface of the hard chrome layer is treated with ultrasonic vibration, with the frequency set between 20 kHz and 50 kHz and the vibration time being 5 minutes to eliminate the interface stress; S6: Coat a layer of silicone resin protective film on the surface of the hardware after ultrasonic treatment, set the curing temperature at 100 to 150 degrees Celsius, and the curing time is not less than 1 hour to provide additional stress buffering effect.

2. A hardware surface treatment process according to claim 1, characterized in that: Cleaning the surface of hardware includes the following sub-steps: Use a 1% aqueous solution of non-ionic surfactant to soak the hardware for 10-15 minutes, then use a soft brush to manually scrub the surface of the hardware; Rinse the hardware with running water to remove the residual surfactant and loose impurities on the surface. After rinsing, place the hardware in an oven at 60-65 degrees Celsius to dry for 30-35 minutes; Use a lint-free cloth dipped in isopropyl alcohol to wipe the surface of the hardware to eventually remove small particles.

3. A hardware surface treatment process according to claim 2, characterized in that: Forming a pre-plating layer on the surface of the hardware includes the following sub-steps: immersing the cleaned hardware in an electrolyte containing nickel salt as an anode, maintaining the electrolyte temperature at 40-45 degrees Celsius, applying a constant current density of 0.5 amperes per square decimeter, and setting the continuous electroplating time to 5-7 minutes; then using deionized water to thoroughly rinse the hardware to prevent electrolyte residue from affecting subsequent processes; after rinsing, placing the hardware in a ventilated place to dry naturally, ready to enter the next process.

4. A hardware surface treatment process according to claim 3, characterized in that: The microcrystallization treatment of the formed pre-plating layer includes the following sub-steps: The formed pre-plated hardware is placed in a microcrystallization bath containing sodium dodecyl sulfate and urea, and the bath temperature is maintained at 30-35 degrees Celsius; a pulse current is applied to the hardware, the frequency is set to 50 Hz, the current density is 1 ampere per square decimeter, and the treatment time is 2 minutes; After completion, immediately remove the hardware from the bath; after removing, immediately rinse the hardware with pure water to remove surface residues; place the hardware in a dry environment to air dry, ensuring that the surface is completely dry before proceeding to the next step.

5. A hardware surface treatment process according to claim 4, characterized in that: The intermediate annealing process includes the following sub-steps: Place the microcrystallized hardware into a furnace preheated to 350 degrees Celsius, gradually increase the furnace temperature to 400 degrees Celsius, and ensure that the furnace is in an inert gas environment; When the specified temperature is reached, this temperature is maintained for 30 minutes, during which the inert gas atmosphere is maintained unchanged. After the insulation period, the furnace is cooled to room temperature. After cooling is completed, the hardware is taken out of the furnace and prepared for the subsequent processing stage.

6. A hardware surface treatment process according to claim 5, characterized in that: The electroplating of hard chrome layer on the annealed hardware includes the following sub-steps: Prepare an electroplating solution containing chromic acid and adjust the pH value to between 4.5 and 5.0, and immerse the annealed hardware as a cathode in the electroplating solution prepared in the first sub-step; Turn on the DC power supply, set the current density to 180 amperes per square meter, and continue electroplating for 20-22 minutes; During electroplating, the plating solution is continuously stirred to ensure that the hard chromium layer is evenly deposited on the surface of the hardware. After electroplating is completed, turn off the power, remove the hardware and rinse it thoroughly with deionized water.

7. A hardware surface treatment process according to claim 6, characterized in that: The surface finishing of the hard chrome layer includes the following sub-steps: Use a 1000-mesh abrasive paste to evenly apply it on the surface of the hard chrome layer after electroplating, and use a polishing machine with a rotation speed of 1000 revolutions per minute and a wool wheel to polish the hardware for 5-7 minutes; After completion, check the surface of the hard chrome layer to confirm that the micro-roughness has been improved; Then, use a high-pressure water spray gun to thoroughly clean the surface of the hardware to remove all abrasive paste residues. After cleaning, wipe the hardware dry with a clean lint-free cloth to ensure that there are no water stains and other contaminants on the surface.

8. A hardware surface treatment process according to claim 7, characterized in that: Applying a nano-scale oxide coating to the polished hard chrome layer includes the following sub-steps: The polished hardware is placed in a vacuum coating chamber, vacuumized, and aluminum metal vapor is introduced into the coating chamber; A layer of aluminum oxide film with a thickness of about 50 nanometers is deposited on the surface of the hard chrome layer by electron beam evaporation. After the deposition process is completed, the pressure in the coating chamber is gradually restored to normal pressure. Take out the hardware and check whether the coating evenly covers the surface of the hard chrome layer to confirm that it is well bonded to the substrate.

9. A hardware surface treatment process according to claim 8, characterized in that: The surface treatment of the hard chrome layer by ultrasonic vibration includes the following sub-steps: Place the hardware with a layer of nano-scale oxide coating on an ultrasonic vibration table, start the ultrasonic device, and adjust the frequency to 30 kHz; After the frequency is set, start the vibration treatment and set the duration to 5 minutes. During the vibration treatment, monitor the working status of the vibration table to ensure that the frequency is stable and the hardware remains stationary; When finished, turn off the ultrasonic device, remove the hardware, and inspect the surface for signs of stress relief.

10. A hardware surface treatment process according to claim 9, characterized in that: Coating a layer of silicone resin protective film on the surface of the hardware after ultrasonic treatment includes the following sub-steps: Evenly spray a layer of silicone resin solution on the surface of the ultrasonically treated hardware; After spraying, let the hardware stand for 10-15 minutes to allow the silicone resin to solidify. During the standing period, prepare the oven and preheat it to 120 degrees Celsius. Place the hardware that has been left to stand in a preheated oven and begin the curing process. The curing time should be no less than 1 hour to allow the silicone resin to fully cure.

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