Water-plating-free bottoming surface treatment method for zinc alloy or aluminum alloy

Abstract

The invention provides a zinc alloy or aluminum alloy water-plating-free bottoming surface treatment method. The zinc alloy or aluminum alloy water-plating-free bottoming surface treatment method comprises the specific steps that (1) a zinc alloy or aluminum alloy workpiece formed through die casting is subjected to deburring and deburring treatment; (2) performing fine wiredrawing treatment on the surface; (3) cleaning and drying the zinc alloy or aluminum alloy workpiece treated in the step (2); (4) the zinc alloy or aluminum alloy workpiece cleaned and dried in the step (3) is put into vacuum coating equipment to be subjected to plasma surface activation; (5) carrying out PVD (Physical Vapor Deposition) multi-arc ion plating treatment on the zinc alloy or aluminum alloy workpiece activated in the step (4); and the treated zinc alloy or aluminum alloy product is obtained. According to the method, the precise wire drawing procedure is added, after the roughness of the surface of the zinc alloy or the aluminum alloy is increased, PVD coating and other procedures can be directly conducted on the surface of the zinc alloy or the aluminum alloy without water plating bottoming operation, and therefore the cost is saved, the product yield is increased, waste water of the electroplating industry cannot be generated, and the requirement for environmental protection is met.

Description

Technical Field

[0001] The invention relates to the technical field of metal surface treatment, in particular to a surface treatment method for zinc alloy or aluminum alloy without water plating primer. Background Art

[0002] Zinc alloy is an alloy composed of zinc and other elements. Commonly added alloying elements include aluminum, copper, magnesium, cadmium, tin, lead, titanium, etc. Zinc alloy die castings have the advantages of cheap materials, low melting point, low energy consumption, good fluidity and formability, full filling, and smooth surface of pressed castings. Therefore, its surface is more suitable for polishing, electroplating and spraying. At present, zinc alloy die castings are increasingly used in the fields of automobiles, electronics, home appliances, bathrooms, etc.

[0003] Aluminum alloy is an alloy with aluminum as the base and a certain amount of other alloying elements added. It is one of the light metal materials. In addition to the general characteristics of aluminum, aluminum alloy has some specific characteristics of alloys due to the different types and quantities of alloying elements added. The density of aluminum alloy is 2.63~2.85g / cm3, with high strength (σb is 110~650MPa), specific strength close to high alloy steel, specific stiffness exceeds steel, good casting performance and plastic processing performance, good electrical and thermal conductivity, good corrosion resistance and weldability, can be used as structural materials, and has a wide range of applications in aerospace, aviation, transportation, construction, electromechanical, light chemical and daily necessities.

[0004] Die-castings with zinc alloy or aluminum alloy substrates generally need to undergo water plating priming, that is, copper, nickel, and chrome plating are performed on the surface of the zinc alloy or aluminum alloy using a non-electrochemical deposition process before higher-level PVD (Physical Vapor Deposition) surface treatment can be performed. Otherwise, the PVD film layer cannot be bonded to the surface of the zinc alloy or aluminum alloy, and the presence of a surface oxide layer causes the PVD film layer to peel off, thus failing to meet the user's high standards for hardness, salt spray, adhesion, etc.

[0005] Water plating is a surface treatment technology that uses electrochemical principles to deposit a metal coating on the surface of a workpiece. Although it has certain environmental protection characteristics and can reduce the emission of harmful chemicals, the wastewater treatment is complicated, and the heavy metals and cyanide contained in it are difficult to meet the country's 2023 "New National Standard for Electroplating Pollutant Emissions" requiring zero cyanide emissions and green environmental protection policies. Summary of the invention

[0006] The purpose of the present invention is to overcome the shortcomings of the prior art, directly omit the water plating primer operation, save costs, improve the yield rate, achieve no electroplating industrial waste water and waste gas emissions, and provide a surface treatment method for zinc alloy or aluminum alloy without water plating primer.

[0007] To achieve the above object, the technical solution provided by the present invention is: a surface treatment method for zinc alloy without water plating primer, and the specific steps include:

[0008] (1) Deburr and trim the zinc alloy workpiece formed by die casting;

[0009] (2) Perform fine wire drawing on the surface of the zinc alloy workpiece processed in (1) to increase the surface roughness of the zinc alloy workpiece;

[0010] (3) Clean and dry the zinc alloy workpiece processed in (2);

[0011] (4) Put the zinc alloy workpiece cleaned and dried in (3) into a vacuum coating equipment for plasma surface activation, bombarding the surface of the zinc alloy workpiece with plasma to clean the surface and form an activation layer;

[0012] (5) Perform PVD multi-arc ion coating treatment on the activated zinc alloy workpiece in (4);

[0013] Obtain the processed zinc alloy product.

[0014] Preferably, the fine wire drawing in step (2) uses silicon carbide material, the grit number of the coarse wire drawing sand belt is 180#, and the grit number of the fine wire drawing sand belt is 320#;

[0015] The vacuum degree in step (4) is up to (1.0×10 -2 )~(1.0×10 -3 ) Pa, introduce argon, the power of the argon ion source is 10 KW, the duty cycle is 50%, the argon gas flow rate is 150 SCCM, the temperature is 100 degrees Celsius, and the time is 5 - 10 minutes.

[0016] Preferably, the cleaning and drying steps in step (3) include:

[0017] (3.1) Perform ultrasonic dewaxing treatment on the zinc alloy workpiece processed in (2);

[0018] (3.2) Perform ultrasonic degreasing treatment on the zinc alloy workpiece processed in (3.1);

[0019] (3.3) Perform reverse osmosis pure water rinsing on the zinc alloy workpiece processed in (3.2);

[0020] (3.4) Dry the zinc alloy workpiece processed in (3.3).

[0021] Furthermore, the concentration of the dewaxing water in step (3.1) is 20 ml / L, the treatment temperature is 60 - 80 degrees Celsius, and the treatment time is 5 minutes;

[0022] The degreasing powder content in step (3.2) is 30 g / L, the treatment temperature is 60 - 80 °C, and the treatment time is 5 minutes;

[0023] The zinc alloy or aluminum alloy workpiece in step (3.3) is rinsed in reverse osmosis pure water at least 5 times;

[0024] The drying temperature in step (3.4) is 100 - 120 °C, and the time is 30 minutes.

[0025] Preferably, the PVD multi-arc ion coating treatment step in step (5) includes:

[0026] (5.1) Perform PVD multi-arc ion deposition of a titanium film layer on the zinc alloy workpiece in (4);

[0027] (5.2) Perform PVD multi-arc ion deposition of a nickel film layer on the zinc alloy workpiece in (5.1);

[0028] (5.3) Perform PVD multi-arc ion deposition of a chromium film layer on the zinc alloy workpiece in (5.2).

[0029] Furthermore, the target material in step (5.1) is a titanium block, the argon gas flow rate is 150 SCCM, the duty cycle is 50%, the internal pressure in the equipment is 0.2 Pa, the current of the titanium block is 100 A, the voltage is 20 V, the temperature is 100 °C, and the deposition time is 5 - 10 minutes;

[0030] The target material in step (5.2) is a nickel block, the argon gas flow rate is 150 SCCM, the duty cycle is 50%, the internal pressure in the equipment is 0.2 Pa, the current of the nickel block is 100 A, the voltage is 20 V, the temperature is 100 °C, and the deposition time is 5 - 10 minutes;

[0031] The target material in step (5.3) is a chromium block, the argon gas flow rate is 150 SCCM, the duty cycle is 50%, the internal pressure in the equipment is 0.2 Pa, the current of the chromium block is 100 A, the voltage is 20 V, the temperature is 100 °C, and the deposition time is 5 - 10 minutes.

[0032] Preferably, it also includes performing AF SiO2 fingerprint-proof treatment on the zinc alloy workpiece after the treatment in step (5).

[0033] Furthermore, the deposition rate of the AF material for fingerprint-proof treatment is 0.8 nm / s, the furnace pressure in the equipment is 0.3 Pa, the temperature is 100 °C, and the time is 10 minutes.

[0034] Preferably, it also includes performing nitriding treatment on the zinc alloy workpiece after the treatment in step (5) using nitrogen;

[0035] And before obtaining the treated zinc alloy product, the zinc alloy workpiece is placed in a baking furnace for baking treatment.

[0036] Further, the ion source power for nitriding treatment is 40 KW, the duty cycle is 50%, the nitrogen gas flow rate is 300 SCCM, the temperature is 100 degrees Celsius, and the time is 10 minutes; the temperature for baking treatment is 120 degrees Celsius, and the baking time is 30 minutes.

[0037] A surface treatment method for aluminum alloy without water plating primer, using the treatment method described in any one of the above, and replacing the zinc alloy workpiece with an aluminum alloy workpiece.

[0038] This solution saves costs, improves the product yield, and does not produce waste water from the electroplating industry, meeting environmental protection requirements by adding a precision wire drawing process to increase the surface roughness of zinc alloy or aluminum alloy, so that PVD coating and other processes can be directly carried out on the surface of zinc alloy or aluminum alloy without the need for water plating primer operation. Specific embodiments

[0039] The present invention will be further described below in conjunction with specific embodiments:

[0040] Taking the process of manufacturing a zinc alloy or aluminum alloy e-cigarette shell as an example.

[0041] Example 1:

[0042] (1) Deburr and remove flash from the die-cast zinc alloy workpiece.

[0043] (2) Polish the zinc alloy workpiece processed in (1) by passing it through a grinding wheel, a hemp wheel, and a wool wheel at 2500 - 3000 RPM respectively.

[0044] (3) Clean and dry the zinc alloy workpiece processed in (2). The specific operations are as follows:

[0045] (3.1) Perform ultrasonic dewaxing treatment on the zinc alloy workpiece processed in (2). The concentration of the dewaxing water is 20 ml / L, the treatment temperature is 60 degrees Celsius, and the treatment time is 5 minutes;

[0046] (3.2) Perform ultrasonic degreasing treatment on the zinc alloy workpiece processed in (3.1). The content of the degreasing powder is 30 g / L, the treatment temperature is 60 degrees Celsius, and the treatment time is 5 minutes;

[0047] (3.3) Rinse the zinc alloy workpiece processed in (3.2) with reverse osmosis pure water and wash it at least 5 times in reverse osmosis pure water;

[0048] (3.4) Dry the zinc alloy workpiece processed in (3.3). The drying temperature is 100 degrees Celsius, and the time is 30 minutes.

[0049] (4) Put the zinc alloy workpieces cleaned and dried in (3) into a vacuum coating equipment for plasma surface activation. Specifically, evacuate to a vacuum degree of (1.0×10 -2 ) Pa, introduce argon gas. The power of the argon ion source is 10 KW, the duty cycle is 50%, the argon gas flow rate is 150 SCCM, the temperature is 100 degrees Celsius, and the time is 5 minutes. Under the condition of high voltage and low current, argon gas bombards the surface of the zinc alloy workpieces, cleaning the surface and forming an activation layer with a thickness of 5 - 10 um.

[0050] (5) Perform PVD multi - arc ion coating treatment on the activated zinc alloy workpieces in (4). The specific operation is as follows:

[0051] (5.1) Perform PVD multi - arc ion deposition of a titanium film layer on the zinc alloy workpieces in (4). The target is a 100×40 mm titanium block. The argon gas flow rate is 150 SCCM, the duty cycle is 50%, the internal pressure in the equipment is 0.2 Pa, the current of the titanium block is 100 A, the voltage is 20 V, the temperature is 100 degrees Celsius, and the deposition time is 5 minutes.

[0052] Obtain the processed zinc alloy product.

[0053] Conduct new energy tests on the above - mentioned products:

[0054] PVD film thickness: 0.2 Um

[0055] Pencil hardness: 2H

[0056] Cross - hatch test: NG

[0057] Neutral salt spray test: 8H

[0058] Artificial sweat test: 1 cycle NG

[0059] For Example 1, without the water plating under - coating operation, after the polishing process, the PVD coating film layer is too thin, the bonding force between the film layer and the substrate is poor, and the performance test fails to meet the standards.

[0060] Example 2:

[0061] (1) Deburr and trim the zinc alloy workpieces formed by die - casting.

[0062] (2) Polish the zinc alloy workpieces processed in (1), passing through a grinding wheel, a hemp wheel, and a wool wheel at 2500 - 3000 RPM respectively.

[0063] (3) Conduct fine wire drawing on the surface of the zinc alloy workpieces processed in (2) to increase the surface roughness of the zinc alloy workpieces. The fine wire drawing uses silicon carbide material. The grit number of the sand belt for rough wire drawing is 180#, and the grit number of the sand belt for fine wire drawing is 320#.

[0064] (4) Clean and dry the processed zinc alloy workpieces in (3). The specific operations are as follows:

[0065] (4.1) Perform ultrasonic dewaxing treatment on the processed zinc alloy workpieces in (3). The concentration of the dewaxing water is 20 ml / L, the treatment temperature is 60 °C, and the treatment time is 5 minutes.

[0066] (4.2) Perform ultrasonic degreasing treatment on the processed zinc alloy workpieces in (4.1). The content of the degreasing powder is 30 g / L, the treatment temperature is 60 °C, and the treatment time is 5 minutes.

[0067] (4.3) Rinse the processed zinc alloy workpieces in (4.2) with reverse osmosis pure water and over - rinse at least 5 times in the reverse osmosis pure water.

[0068] (4.4) Dry the processed zinc alloy workpieces in (4.3). The drying temperature is 100 °C and the time is 30 minutes.

[0069] (5) Put the cleaned and dried zinc alloy workpieces in (4) into a vacuum coating equipment for plasma surface activation. Specifically, evacuate to (1.0×10 -2 ) Pa, introduce argon gas. The power of the argon ion source is 10 KW, the duty cycle is 50%, the argon gas flow rate is 150 SCCM, the temperature is 100 °C, and the time is 5 minutes. The argon gas bombards the surface of the zinc alloy workpieces under high voltage and low current, cleans the surface and forms an activation layer with a thickness of 5 - 10 μm.

[0070] (6) Perform PVD multi - arc ion coating treatment on the activated zinc alloy workpieces in (5). The specific operations are as follows:

[0071] (6.1) Perform PVD multi - arc ion deposition of a titanium film layer on the zinc alloy workpieces in (5). The target is a 100×40 mm titanium block, the argon gas flow rate is 150 SCCM, the duty cycle is 50%, the internal pressure in the equipment is 0.2 Pa, the current of the titanium block is 100 A, the voltage is 20 V, the temperature is 100 °C, and the deposition time is 5 minutes.

[0072] (6.2) Perform PVD multi - arc ion deposition of a nickel film layer on the zinc alloy workpieces in (6.1). The target is a 100×40 mm nickel block, the argon gas flow rate is 150 SCCM, the duty cycle is 50%, the internal pressure in the equipment is 0.2 Pa, the current of the nickel block is 100 A, the voltage is 20 V, the temperature is 100 °C, and the deposition time is 5 minutes.

[0073] Obtain the processed zinc alloy product.

[0074] Conduct performance tests on the above - mentioned products:

[0075] PVD film thickness: 0.5 Um

[0076] Pencil hardness: 2H

[0077] Cross cut test: NG

[0078] Neutral salt spray test: 24H

[0079] Artificial sweat test: 1 cycle NG

[0080] For Example 2, after the water plating undercoat operation was not performed, after the polishing process, a fine wire drawing process was added to increase the surface roughness to increase the adhesion. After PVD titanium plating, a PVD nickel plating process was added to form a composite film layer. Compared with Example 1, the PVD film layer thickness increased from 0.2 Um to 0.5 Um, and the bonding strength between the film layer and the substrate was improved, but the performance test still did not meet the standards.

[0081] Example 3:

[0082] (1) Deburr and trim the zinc alloy workpieces formed by die casting.

[0083] (2) Perform a fine wire drawing process on the surface of the zinc alloy workpieces processed in (1) to increase the surface roughness of the zinc alloy workpieces. The fine wire drawing uses silicon carbide material, the grit number of the coarse wire drawing abrasive belt is 180#, and the grit number of the fine wire drawing abrasive belt is 320#.

[0084] (3) Clean and dry the zinc alloy workpieces processed in (2). The specific operations are as follows:

[0085] (3.1) Perform ultrasonic dewaxing on the zinc alloy workpieces processed in (2). The concentration of the dewaxing water is 20 ml / L, the processing temperature is 60 degrees Celsius, and the processing time is 5 minutes;

[0086] (3.2) Perform ultrasonic degreasing on the zinc alloy workpieces processed in (3.1). The content of the degreasing powder is 30 g / L, the processing temperature is 60 degrees Celsius, and the processing time is 5 minutes;

[0087] (3.3) Rinse the zinc alloy workpieces processed in (3.2) with reverse osmosis pure water and over - rinse at least 5 times in the reverse osmosis pure water;

[0088] (3.4) Dry the zinc alloy workpieces processed in (3.3). The drying temperature is 100 degrees Celsius and the time is 30 minutes.

[0089] (4) Put the zinc alloy workpieces cleaned and dried in (3) into a vacuum coating equipment for plasma surface activation. The specific vacuum degree is pumped to (1.0×10 -2)Pa, introduce argon gas. The power of the argon ion source is 10KW, the duty cycle is 50%, the argon gas flow rate is 150 SCCM, the temperature is 100 degrees Celsius, and the time is 5 minutes. Under high voltage and low current, the argon gas performs plasma bombardment on the surface of the zinc alloy workpiece, cleaning the surface and forming an activation layer with a thickness of 5 - 10um.

[0090] (5) Perform PVD multi-arc ion coating treatment on the activated zinc alloy workpiece in (4). The specific operation is as follows:

[0091] (5.1) Perform PVD multi-arc ion deposition of a titanium film layer on the zinc alloy workpiece in (4). The target is a 100×40mm titanium block, the argon gas flow rate is 150 SCCM, the duty cycle is 50%, the internal pressure in the equipment is 0.2 Pa, the current of the titanium block is 100A, the voltage is 20V, the temperature is 100 degrees Celsius, and the deposition time is 5 minutes;

[0092] (5.2) Perform PVD multi-arc ion deposition of a nickel film layer on the zinc alloy workpiece in (5.1). The target is a 100×40mm nickel block, the argon gas flow rate is 150 SCCM, the duty cycle is 50%, the internal pressure in the equipment is 0.2 Pa, the current of the nickel block is 100A, the voltage is 20V, the temperature is 100 degrees Celsius, and the deposition time is 5 minutes;

[0093] (5.3) Perform PVD multi-arc ion deposition of a chromium film layer on the zinc alloy workpiece in (5.2). The target is a 100×40mm chromium block, the argon gas flow rate is 150 SCCM, the duty cycle is 50%, the internal pressure in the equipment is 0.2 Pa, the current of the chromium block is 100A, the voltage is 20V, the temperature is 100 degrees Celsius, and the deposition time is 5 minutes.

[0094] Obtain the processed zinc alloy product.

[0095] Conduct performance tests on the above products:

[0096] PVD film thickness: 1Um

[0097] Pencil hardness: 2H

[0098] Cross-cut test: OK

[0099] Neutral salt spray test: 36H

[0100] Artificial sweat test: 1 cycle OK

[0101] For Example 3, the polishing process is removed, and the fine wire drawing process is retained. The principle of increasing the surface roughness to improve adhesion remains unchanged. On the basis of PVD titanium plating and PVD nickel plating, an additional PVD chromium plating is added to form a three-layer composite film layer. Comparing Examples 1 and 2, the thickness of the PVD film layer increases from 0.5 μm to 1.0 μm, the bonding strength is significantly enhanced, and it can pass the cross-cut test. Other properties can also be further enhanced.

[0102] Example 4:

[0103] (1) Deburr and trim the die-cast zinc alloy workpieces.

[0104] (2) Perform fine wire drawing on the surface of the zinc alloy workpieces processed in (1) to increase the surface roughness of the zinc alloy workpieces. Silicon carbide is used for fine wire drawing. The grit size of the coarse wire drawing abrasive belt is 180#, and the grit size of the fine wire drawing abrasive belt is 320#.

[0105] (3) Clean and dry the zinc alloy workpieces processed in (2). The specific operations are as follows:

[0106] (3.1) Perform ultrasonic dewaxing on the zinc alloy workpieces processed in (2). The concentration of the dewaxing water is 20 ml / L, the processing temperature is 80 °C, and the processing time is 5 minutes;

[0107] (3.2) Perform ultrasonic degreasing on the zinc alloy workpieces processed in (3.1). The content of the degreasing powder is 30 g / L, the processing temperature is 80 °C, and the processing time is 5 minutes;

[0108] (3.3) Rinse the zinc alloy workpieces processed in (3.2) with reverse osmosis pure water and overwash at least 5 times in reverse osmosis pure water;

[0109] (3.4) Dry the zinc alloy workpieces processed in (3.3). The drying temperature is 100 °C and the time is 30 minutes.

[0110] (4) Place the cleaned and dried zinc alloy workpieces into a vacuum coating equipment for plasma surface activation. Specifically, evacuate to a vacuum degree of (1.0×10 -3 ) Pa, introduce argon gas. The power of the argon ion source is 10 KW, the duty cycle is 50%, the argon gas flow rate is 150 SCCM, the temperature is 100 °C, and the time is 5 minutes. The argon gas bombards the surface of the zinc alloy workpieces under high voltage and low current to clean the surface and form an activation layer with a thickness of 5 - 10 μm.

[0111] (5) Perform PVD multi-arc ion coating on the activated zinc alloy workpieces in (4). The specific operations are as follows:

[0112] (5.1) Perform PVD multi-arc ion deposition of a titanium film layer on the zinc alloy workpiece in (4). The target is a 100×40 mm titanium block, the argon gas flow rate is 150 SCCM, the duty cycle is 50%, the internal pressure in the equipment is 0.2 Pa, the current of the titanium block is 100 A, the voltage is 20 V, the temperature is 100 degrees Celsius, and the deposition time is 5 minutes;

[0113] (5.2) Perform PVD multi-arc ion deposition of a nickel film layer on the zinc alloy workpiece in (5.1). The target is a 100×40 mm nickel block, the argon gas flow rate is 150 SCCM, the duty cycle is 50%, the internal pressure in the equipment is 0.2 Pa, the current of the nickel block is 100 A, the voltage is 20 V, the temperature is 100 degrees Celsius, and the deposition time is 5 minutes;

[0114] (5.3) Perform PVD multi-arc ion deposition of a chromium film layer on the zinc alloy workpiece in (5.2). The target is a 100×40 mm chromium block, the argon gas flow rate is 150 SCCM, the duty cycle is 50%, the internal pressure in the equipment is 0.2 Pa, the current of the chromium block is 100 A, the voltage is 20 V, the temperature is 100 degrees Celsius, and the deposition time is 10 minutes.

[0115] (6) Perform AF SiO2 anti-fingerprint treatment on the zinc alloy workpiece after treatment in (5). The deposition rate of the AF material for anti-fingerprint treatment is 0.8 nm / s, the furnace pressure in the equipment is 0.3 Pa, the temperature is 100 degrees Celsius, and the time is 10 minutes.

[0116] Obtain the treated zinc alloy product.

[0117] Perform new energy tests on the above products:

[0118] PVD film thickness: 2 Um

[0119] Pencil hardness: 3H

[0120] Cross-cut test: OK

[0121] Neutral salt spray test: 48H

[0122] Artificial sweat test: 2 cycles OK

[0123] For Example 4, the PVD chromium plating time is increased from 5 minutes to 10 minutes to increase the thickness of the chromium film layer, and then silicon plating and silicone anti-fingerprint treatment are added. Comparing with Examples 1-3, the PVD film layer thickness is increased from 1 UM to 2 Um, and the bonding force is further strengthened, and all performance tests are improved compared with before.

[0124] Example 5:

[0125] (1) Deburr and trim the die-cast zinc alloy workpiece.

[0126] (2) Perform a fine wire drawing treatment on the surface of the zinc alloy workpiece processed in (1) to increase the surface roughness of the zinc alloy workpiece. The fine wire drawing uses silicon carbide material. The grit size of the sand belt for rough wire drawing is 180#, and the grit size of the sand belt for fine wire drawing is 320#.

[0127] (3) Clean and dry the zinc alloy workpiece processed in (2). The specific operations are as follows:

[0128] (3.1) Perform an ultrasonic dewaxing treatment on the zinc alloy workpiece processed in (2). The concentration of the dewaxing water is 20 ml / L, the treatment temperature is 60 degrees Celsius, and the treatment time is 5 minutes.

[0129] (3.2) Perform an ultrasonic degreasing treatment on the zinc alloy workpiece processed in (3.1). The content of the degreasing powder is 30 g / L, the treatment temperature is 60 degrees Celsius, and the treatment time is 5 minutes.

[0130] (3.3) Rinse the zinc alloy workpiece processed in (3.2) with reverse osmosis pure water and over - rinse it at least 5 times in the reverse osmosis pure water.

[0131] (3.4) Dry the zinc alloy workpiece processed in (3.3). The drying temperature is 120 degrees Celsius, and the time is 30 minutes.

[0132] (4) Put the zinc alloy workpiece after cleaning and drying in (3) into a vacuum coating equipment for plasma surface activation. Specifically, evacuate to a vacuum degree of (1.0×10 -2 ) Pa, introduce argon gas. The power of the argon ion source is 10 KW, the duty cycle is 50%, the argon gas flow rate is 150 SCCM, the temperature is 100 degrees Celsius, and the time is 5 minutes. The argon gas bombards the surface of the zinc alloy workpiece under high voltage and low current, cleans the surface and forms an activation layer with a thickness of 5 - 10 um.

[0133] (5) Perform a PVD multi - arc ion coating treatment on the activated zinc alloy workpiece in (4). The specific operations are as follows:

[0134] (5.1) Perform PVD multi - arc ion deposition of a titanium film layer on the zinc alloy workpiece in (4). The target is a 100×40 mm titanium block. The argon gas flow rate is 150 SCCM, the duty cycle is 50%, the internal pressure in the equipment is 0.2 Pa, the current of the titanium block is 100 A, the voltage is 20 V, the temperature is 100 degrees Celsius, and the deposition time is 10 minutes.

[0135] (5.2) Perform PVD multi-arc ion deposition of a nickel film layer on the zinc alloy workpiece in (5.1). The target is a 100×40 mm nickel block, the argon gas flow rate is 150 SCCM, the duty cycle is 50%, the internal pressure in the equipment is 0.2 Pa, the current of the nickel block is 100 A, the voltage is 20 V, the temperature is 100 degrees Celsius, and the deposition time is 10 minutes;

[0136] (5.3) Perform PVD multi-arc ion deposition of a chromium film layer on the zinc alloy workpiece in (5.2). The target is a 100×40 mm chromium block, the argon gas flow rate is 150 SCCM, the duty cycle is 50%, the internal pressure in the equipment is 0.2 Pa, the current of the chromium block is 100 A, the voltage is 20 V, the temperature is 100 degrees Celsius, and the deposition time is 10 minutes.

[0137] (6) Perform nitriding treatment on the zinc alloy workpiece processed in (5) using nitrogen. The ion source power for nitriding treatment is 40 KW, the duty cycle is 50%, the nitrogen gas flow rate is 300 SCCM, the temperature is 100 degrees Celsius, and the time is 10 minutes.

[0138] (7) Perform AF SiO2 fingerprint-proof treatment on the zinc alloy workpiece processed in (6). The deposition rate of the AF material for fingerprint-proof treatment is 0.8 nm / s, the furnace pressure in the equipment is 0.3 Pa, the temperature is 100 degrees Celsius, and the time is 10 minutes.

[0139] (8) Place the zinc alloy workpiece processed in (7) into a baking oven for baking treatment. The baking temperature is 120 degrees Celsius, and the baking time is 30 minutes.

[0140] Obtain the processed zinc alloy product.

[0141] Perform new energy tests on the above products:

[0142] PVD film thickness: 4 - 5 Um

[0143] Pencil hardness: above 4H

[0144] Cross-cut test: OK

[0145] Neutral salt spray test: 96H

[0146] Artificial sweat test: 4 cycles

[0147] MEK acetone solvent test: 50 times

[0148] For Example 5, the temperature of ultrasonic dewaxing and ultrasonic degreasing is increased from 60 degrees Celsius to 80 degrees Celsius, making the workpiece cleaner in dewaxing and degreasing. The drying temperature is increased by 20 degrees Celsius, which can reduce the moisture in the screw holes. The vacuum degree is increased from (1.0×10 -2 ) to (1.0×10 -3)Pa can significantly reduce the miscellaneous gas generated during PVD coating of workpieces, increase the time for PVD titanium plating, nickel plating, and chromium plating, and increase the thickness of the coating. Adding a nitriding process can further stabilize the PVD coating in a vacuum furnace.

[0149] Aluminum alloy workpieces can, like zinc alloy workpieces, produce qualified products with the same effect using the above processes.

[0150] From the above embodiments, it can be seen that zinc alloy or aluminum alloy die-cast hardware parts can be directly PVD coated without the need for water plating as a primer, thus saving costs. Moreover, the products have no bubbles, no pitting, no electroplating burrs and other defective phenomena, improving the product yield. There is also no electroplating industrial wastewater generated, meeting the requirements of the "New National Standard for Electroplating Pollutant Emissions" proposed in 2023 by the state for the zero-emission of cyanide in the green environmental protection policy and meeting the environmental protection requirements.

Claims

1. A surface treatment method for zinc alloy or aluminum alloy without water plating as a primer, characterized in that: The specific steps include: (1) Deburr and remove flash from the die-cast zinc alloy or aluminum alloy workpieces; (2) Perform fine wire drawing on the surface of the zinc alloy or aluminum alloy workpieces processed in (1) to increase the surface roughness of the zinc alloy or aluminum alloy workpieces; (3) Clean and dry the zinc alloy or aluminum alloy workpieces processed in (2); (4) Put the zinc alloy or aluminum alloy workpieces cleaned and dried in (3) into a vacuum coating equipment for plasma surface activation, bombarding the surface of the zinc alloy or aluminum alloy workpieces with plasma to clean the surface and form an activation layer; (5) Perform PVD multi-arc ion coating treatment on the activated zinc alloy or aluminum alloy workpieces in (4); Obtain the processed zinc alloy or aluminum alloy products.

2. The surface treatment method for zinc alloy or aluminum alloy without water plating primer according to claim 1, characterized in that: The cleaning and drying steps in step (3) include: (3.1) Perform ultrasonic wax removal on the zinc alloy or aluminum alloy workpieces processed in (2); (3.2) Perform ultrasonic degreasing on the zinc alloy or aluminum alloy workpieces processed in (3.1); (3.3) Rinse the zinc alloy or aluminum alloy workpieces processed in (3.2) with reverse osmosis pure water; (3.4) Dry the zinc alloy or aluminum alloy workpieces processed in (3.3).

3. A surface treatment method for zinc alloy or aluminum alloy without water plating as the primer according to claim 1, characterized in that: The PVD multi-arc ion coating treatment steps in step (5) include: (5.1) Perform PVD multi-arc ion deposition of a titanium film layer on the zinc alloy or aluminum alloy workpieces in (4); (5.2) Perform PVD multi-arc ion deposition of a nickel film layer on the zinc alloy or aluminum alloy workpieces in (5.1); (5.3) Perform PVD multi-arc ion deposition of a chromium film layer on the zinc alloy or aluminum alloy workpieces in (5.2).

4. A surface treatment method for zinc alloy without water plating as the primer according to claim 1, characterized in that: It also includes performing AF SiO2 anti-fingerprint treatment on the zinc alloy or aluminum alloy workpieces after the treatment in step (5).

5. The surface treatment method for zinc alloy without water plating as the primer according to claim 1 or 4, characterized in that: It also includes performing nitriding treatment on the zinc alloy or aluminum alloy workpieces after the treatment in step (5) using nitrogen; And before obtaining the processed zinc alloy or aluminum alloy products, bake the zinc alloy or aluminum alloy workpieces in a baking furnace.

6. A surface treatment method for zinc alloy or aluminum alloy without water plating primer, characterized in that: The fine wire drawing in step (2) uses silicon carbide material, and the grit number of the coarse wire drawing abrasive belt is 180#, and the grit number of the fine wire drawing abrasive belt is 320#; The degree of vacuum in step (4) is from (1.0×10 -2 ) to (1.0×10 -3 ) Pa. Argon is introduced. The power of the argon ion source is 10 KW, the duty cycle is 50%, the argon gas flow rate is 150 SCCM, the temperature is 100 degrees Celsius, and the time is 5 - 10 minutes.

7. According to the surface treatment method for zinc alloy or aluminum alloy waterless electroplating primer-free described in claim 2, wherein: The concentration of the wax removal water in step (3.1) is 20 ml / L, the treatment temperature is 60 - 80 degrees Celsius, and the treatment time is 5 minutes; The content of the degreasing powder in step (3.2) is 30 g / L, the treatment temperature is 60 - 80 degrees Celsius, and the treatment time is 5 minutes; The zinc alloy or aluminum alloy workpieces in step (3.3) are rinsed in reverse osmosis pure water at least 5 times; The drying temperature in step (3.4) is 100 - 120 degrees Celsius, and the time is 30 minutes.

8. According to the surface treatment method for zinc alloy or aluminum alloy waterless electroplating primer-free described in claim 3, wherein: The target in step (5.1) is a titanium block, the argon gas flow rate is 150 SCCM, the duty cycle is 50%, the internal pressure in the equipment is 0.2 Pa, the current of the titanium block is 100 A, the voltage is 20 V, the temperature is 100 degrees Celsius, and the deposition time is 5 - 10 minutes; The target in step (5.2) is a nickel block, the argon gas flow rate is 150 SCCM, the duty cycle is 50%, the internal pressure in the equipment is 0.2 Pa, the current of the nickel block is 100 A, the voltage is 20 V, the temperature is 100 degrees Celsius, and the deposition time is 5 - 10 minutes; The target in step (5.3) is a chromium block, the argon gas flow rate is 150 SCCM, the duty cycle is 50%, the internal pressure in the equipment is 0.2 Pa, the current of the chromium block is 100 A, the voltage is 20 V, the temperature is 100 degrees Celsius, and the deposition time is 5 - 10 minutes.

9. A surface treatment method for zinc alloy or aluminum alloy without water plating primer, characterized in that: The deposition rate of the AF material for anti - fingerprint treatment is 0.8 nm / s, the pressure in the furnace of the equipment is 0.3 Pa, the temperature is 100 degrees Celsius, and the time is 10 minutes.

10. A surface treatment method for zinc alloy or aluminum alloy without water plating as a primer, characterized in that: The ion source power for nitriding treatment is 40 KW, the duty cycle is 50%, the nitrogen gas flow rate is 300 SCCM, the temperature is 100 degrees Celsius, and the time is 10 minutes; the temperature for baking treatment is 120 degrees Celsius, and the baking time is 30 minutes.