A plating process for a metal encapsulation housing of a radio frequency interference filter

Abstract

The application discloses a plating process of a metal packaging shell of a radio frequency interference filter, which comprises the following steps: S1, electroplating a nickel layer on the outer wall of the shell, the inner wall of a blind hole and a lead wire; S2, electroplating a gold layer one on the nickel layer, wherein the thickness of the gold layer one is 0.01-0.05 um; S3, electroplating a gold layer two on the gold layer one, wherein the thickness of the gold layer two is 0.09-0.15 um; S4, electroplating a gold layer three on the outer wall of the shell and the lead wire located outside the blind hole, wherein the gold layer three is deposited on the gold layer two, and the thickness of the gold layer three is 0.2-0.6 um; and S5, electroplating a gold layer four on the lead wire located outside the blind hole, wherein the gold layer four is deposited on the gold layer three, and the thickness of the gold layer four is 2.5-4.2 um. The gold layer is electroplated by multiple steps, so that the thickness of the gold layer electroplated on each part can better meet the requirements, and the thickness fluctuation is small.

Description

Technical Field

[0001] This application relates to the field of metal packaging shell plating technology, and in particular to a plating process for a metal packaging shell of a radio frequency interference filter. Background Technology

[0002] Radio frequency interference filters consist of a metal enclosure and filtering elements housed within it. The metal enclosure provides circuit support, electrical signal transmission, heat dissipation, sealing, and chemical protection. Figure 1 As shown, the metal encapsulation housing includes a housing 1, a lead wire 2, and a substrate. The housing 1 is provided with a sealing hole 11. The lead wire 2 is disposed in the sealing hole 11 through a glass insulator 3. The inner sidewall of the sealing hole 11 and the lower surface of the glass insulator 3 form a blind hole 12.

[0003] To better meet performance requirements, the housing and leads must first be electroplated with a nickel layer, followed by a gold layer, with strict requirements on the thickness of both the nickel and gold layers. Figure 1 As shown, A1, A2, and A3 are any three points in the designated area of ​​the lead wire located outside the blind hole 12. Point A1 is any point on the lead wire end face at the opening end of the housing, point A2 is any point on the outer wall of the lead wire at the opening end of the housing, and point A3 is any point on the outer wall of the lead wire at the glass insulator end. The nickel layer thickness of A1, A2, and A3 should satisfy 3µm≤(A1+A2+A3) / 3≤5µm, and the gold layer thickness should satisfy 2.8µm≤(A1+A2+A3) / 3≤5µm; B1, B2, and B3 are any three points on the outer wall of the housing. The nickel layer thickness of B1, B2, and B3 should satisfy 3µm≤(B1+B2+B3) / 3≤5µm, and the gold layer thickness should satisfy 0.3µm≤(B1+B2+B3) / 3≤0.8µm; C1, C2, and C3 For any three points on the inner wall of the blind via, C1, C2, and C3 should have a nickel layer thickness of 3µm ≤ (C1 + C2 + C3) / 3 ≤ 5µm and a gold layer thickness of 0.1µm ≤ (A1 + A2 + A3) / 3 ≤ 0.2µm. For any three points on the outer wall of the lead located inside the blind via, D1, D2, and D3 should have a nickel layer thickness of 3µm ≤ (D1 + D2 + D3) / 3 ≤ 5µm and a gold layer thickness of 0.1µm ≤ (D1 + D2 + D3) / 3 ≤ 0.2µm.

[0004] Currently, the process for plating nickel and gold onto the metal package of an RF interference filter involves: first, barrel plating to deposit a 3-5µm thick nickel layer on the package and leads; then, barrel plating again to deposit a 0.3-0.8µm thick gold layer on the package and leads; finally, rack plating to electroplate a gold layer onto the leads outside the blind vias, resulting in a 2.8-5µm thick gold layer on the leads outside the package. However, this plating process results in a gold layer thickness on the inner wall of the blind vias exceeding requirements, increasing costs. Furthermore, because the gold plating on the package is done in a single electroplating process, the package and leads need to remain in the plating bath for approximately 20 minutes. This prolonged stay causes extremely uneven circulation of the plating solution within the blind vias, leading to significant fluctuations in the thickness of the gold layer on the inner wall of the blind vias, thus affecting the heat dissipation performance of the metal package. Summary of the Invention

[0005] In order to solve at least one of the above-mentioned technical problems, and to develop a plating process that can better meet the requirements for the thickness of the gold layer electroplated on the inner wall of the blind hole, and has small fluctuations in the thickness of the gold layer electroplated on the inner wall of the blind hole, this application provides a plating process for the metal packaging shell of a radio frequency interference filter.

[0006] This application provides a plating process for the metal package housing of a radio frequency interference filter, including the following steps:

[0007] S1. Electroplating a nickel layer on the outer wall of the housing, the inner wall of the blind hole, and the lead wire;

[0008] S2. Electroplating a gold layer one on the nickel layer, the thickness of the gold layer one being 0.01~0.05um;

[0009] S3. Electroplating a second gold layer on the first gold layer, the thickness of the second gold layer being 0.09–0.15 μm;

[0010] S4. Gold layer three is electroplated on the outer wall of the shell and on the lead wire located outside the blind hole. Gold layer three is deposited on gold layer two and the thickness of gold layer three is 0.2~0.6um.

[0011] S5. Electroplating a fourth gold layer on the lead outside the blind via. The fourth gold layer is deposited on the third gold layer, and the thickness of the fourth gold layer is 2.5 to 4.2 μm.

[0012] By adopting the above technical solution, the gold layer on the inner wall of the blind hole and the gold layer on the lead wire inside the blind hole have the same thickness, both consisting of gold layer one and gold layer two. The gold layer on the outer wall of the shell consists of gold layer one to gold layer three, and the gold layer on the lead wire outside the blind hole consists of gold layer one to gold layer four. This ensures that the thickness of the gold layer electroplated in each part meets the requirements well. Since the gold layer is electroplated in multiple steps, the time that the shell and the lead wire stay in the electroplating solution is short each time the gold layer is electroplated. This results in smaller fluctuations and more uniform thickness of the gold layer deposited on the inner wall of the blind hole, the outer wall of the shell, and the lead wire.

[0013] Optionally, before step S1, the housing and leads may also undergo degreasing, chemical polishing, and other treatments.

[0014] By adopting the above technical solution, the oxide layer on the surface of the shell and the lead wire can be effectively removed, so as to avoid the occurrence of defects such as bubbles, black spots and discoloration on the surface of the shell caused by the oxide layer during the electroplating process.

[0015] Optionally, in step S1, a nickel layer is electroplated on the outer wall of the housing, the inner wall of the blind hole, and the lead wire using a horizontal barrel plating method, with a nickel layer thickness of 3-5 μm.

[0016] Optionally, in step S2, the first gold plating layer is deposited using a horizontal barrel plating method. The shell and leads with the nickel layer deposited are placed into a barrel containing the gold plating solution. The barrel rotates at a speed of 5 to 15 revolutions per minute for 0.5 to 1 minute, so that the first gold layer is deposited on the nickel layer.

[0017] By adopting the above technical solution, the residence time of the shell and leads in the gold plating solution is shorter, much shorter than the existing residence time. This avoids the problem of uneven circulation of the electroplating solution in the blind hole, thereby making the thickness fluctuation of the gold layer on the inner wall of the blind hole and the leads in the blind hole smaller.

[0018] Optionally, in step S3, the second gold plating layer is deposited using a horizontal barrel plating method. The shell with the first gold layer and the lead wire are placed into a barrel containing a gold plating solution. The barrel rotates at a speed of 5 to 15 revolutions per minute for 1 to 2 minutes, so that the second gold layer is deposited on the first gold layer.

[0019] By adopting the above technical solution, the sum of the thicknesses of gold layer one and gold layer two can better meet the requirements of the inner wall of the blind hole and the lead wire located in the blind hole for the thickness of the electroplated gold layer.

[0020] Optionally, step S4, before electroplating the third gold layer, also includes sealing the inner wall of the blind hole and the lead wire located in the blind hole.

[0021] By adopting the above technical solution, since the thickness of the gold layer plated on the inner wall of the blind hole and the lead wire located in the blind hole already meets the requirements, sealing these two parts can prevent the deposition of excess gold layer in these two parts during the subsequent gold plating process.

[0022] Optionally, a sealing clamp is used for sealing. The sealing clamp is made of Teflon and has a connecting hole. The diameter of the connecting hole is smaller than the radial diameter of the lead wire. When the sealing clamp is engaged with the lead wire, the lower end face of the blind hole is in close contact with the sealing clamp.

[0023] By adopting the above technical solution, the interference fit between the lead wire and the corresponding connecting hole can prevent the electroplating solution from contacting the lead wire in the blind hole during subsequent electroplating. The lower end face of the blind hole is tightly attached to the sealing fixture to prevent the electroplating solution from entering the blind hole 12 and contacting the inner wall of the blind hole during subsequent electroplating.

[0024] Optionally, the sealing clamp includes a support plate, the support plate having an electroplating hole, and a boss that can be embedded in a blind hole on the support plate above the electroplating hole, the boss having a connecting hole communicating with the electroplating hole.

[0025] Optionally, a guide hole is provided on the connection hole.

[0026] By adopting the above technical solution, the guide hole facilitates the insertion of the lead wire into the connection hole.

[0027] Optionally, in step S5, the fourth gold plating layer is plated using a rack plating method.

[0028] In summary, this application includes at least one of the following beneficial technical effects:

[0029] 1. The thickness of the gold layer on the inner wall of the blind hole and the thickness of the gold layer on the lead wire inside the blind hole are the same, both consisting of gold layer one and gold layer two. The gold layer on the outer wall of the shell consists of gold layer one, gold layer two and gold layer three. The gold layer on the lead wire outside the blind hole consists of gold layer one, gold layer two, gold layer three and gold layer four, thus ensuring that the thickness of the electroplated gold layer in each part meets the requirements well.

[0030] 2. Because the gold layer is electroplated in multiple steps, the time that the shell and leads spend in the electroplating solution is relatively short each time the gold layer is electroplated. This results in smaller fluctuations and more uniform thickness of the gold layer deposited on the inner wall of the blind hole, the outer wall of the shell, and the leads.

[0031] 3. When the thickness of the gold plating on the inner wall of the blind hole and the lead wire located in the blind hole meets the requirements, these two parts are sealed with sealing clamps to prevent excess gold from being deposited in these two parts during subsequent gold plating.

[0032] 4. The sealing clamp has a simple structure, is easy to operate, and the shell can be reused repeatedly after cleaning. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the structure of an existing metal packaging shell;

[0034] Figure 2 A schematic diagram of the structure of the sealing clamp provided in this application for sealing the blind hole and the lead wire located in the blind hole;

[0035] Figure 3 This is an enlarged structural diagram of part E;

[0036] Explanation of reference numerals in the attached drawings: 1. Housing; 11. Sealing hole; 12. Blind hole; 2. Lead wire; 3. Glass insulator; 4. Sealing clamp; 41. Support plate; 42. Electroplating hole; 43. Boss; 44. Connecting hole; 45. Guide hole. Detailed Implementation

[0037] The present application will be further described in detail below with reference to the accompanying drawings and embodiments.

[0038] This application designs a plating process for the metal packaging shell of a radio frequency interference filter.

[0039] The metal packaging shell of the radio frequency interference filter disclosed in this application is prepared by the following method, including the following steps:

[0040] S1. Electroplating a nickel layer on the outer wall of the housing, the inner wall of the blind hole, and the lead wire;

[0041] S2. Electroplating a gold layer one on the nickel layer, the thickness of the gold layer one being 0.01~0.05um;

[0042] S3. Electroplating a second gold layer on the first gold layer, the thickness of the second gold layer being 0.09–0.15 μm;

[0043] S4. Gold layer three is electroplated on the outer wall of the shell and on the lead wire located outside the blind hole. Gold layer three is deposited on gold layer two and the thickness of gold layer three is 0.2~0.6um.

[0044] S5. Electroplating a fourth gold layer on the lead outside the blind via. The fourth gold layer is deposited on the third gold layer, and the thickness of the fourth gold layer is 2.5 to 4.2 μm.

[0045] The gold layer on the inner wall of the blind hole and the gold layer on the lead wire inside the blind hole have the same thickness, both consisting of gold layer one and gold layer two. The gold layer on the outer wall of the shell consists of gold layer one to gold layer three, and the gold layer on the lead wire outside the blind hole consists of gold layer one to gold layer four. This ensures that the thickness of the gold layer electroplated in each part meets the requirements well. Since the gold layer is electroplated in multiple steps, the time that the shell and the lead wire spend in the electroplating solution is short each time the gold layer is electroplated. This results in smaller fluctuations and more uniformity in the thickness of the gold layer deposited on the inner wall of the blind hole, the outer wall of the shell, and the lead wire.

[0046] In the above technical solution, optionally, step S4, before electroplating the third gold layer, further includes sealing the inner wall of the blind hole and the lead wire located in the blind hole.

[0047] By adopting the above technical solution, since the thickness of the gold layer plated on the inner wall of the blind hole and the lead wire located in the blind hole already meets the requirements, sealing these two parts can prevent the deposition of excess gold layer in these two parts during the subsequent gold plating process.

[0048] Example 1

[0049] A plating process for the metal package housing of a radio frequency interference filter includes the following steps:

[0050] S1. Cleaning and degreasing

[0051] The housing and its leads are immersed in a potassium ferricyanide solution for chemical cleaning using ultrasound. After cleaning, the housing and leads are rinsed with tap water and deionized water in sequence. The cleaned housing and its leads are then immersed in an electrolyte solution for degreasing using electrolysis. After degreasing, the housing and leads are rinsed with tap water and deionized water in sequence.

[0052] S2, chemical polishing

[0053] After cleaning and degreasing, the housing and its leads are immersed in a polishing solution for chemical polishing to remove the oxide layer on the surface of the housing and leads. The polishing solution is a mixture of 85% concentrated phosphoric acid and 5% hydrogen peroxide by mass, with a weight ratio of 7:3 for phosphoric acid to hydrogen peroxide. After chemical polishing, the housing and leads are rinsed with tap water and deionized water in sequence.

[0054] S3, nickel plating layer

[0055] The housing and its leads are placed in a drum containing a nickel plating solution and rotated at 5 rpm for 10 minutes to perform horizontal barrel plating on the housing and its leads. This process deposits a nickel layer of 4 μm thickness on the outer wall of the housing, the inner wall of the blind holes, and the outer wall of the leads. After the nickel plating, the nickel layer on the housing and leads is rinsed with tap water and then with deionized water.

[0056] S4, Pre-plated gold

[0057] The shell with the nickel layer and the leads are placed in a drum containing a gold plating solution. The drum is rotated at 10 rpm for 0.5 minutes to perform horizontal barrel plating on the shell and the leads on the shell, so that a gold layer with a thickness of 0.01 μm is deposited on the nickel layer.

[0058] S5, barrel-plated gold

[0059] The housing with the first gold layer deposited and the leads are placed in a drum containing a gold plating solution. The drum is rotated at 5 rpm for 1.5 minutes to perform horizontal barrel plating on the housing and leads, so that a second gold layer with a thickness of 0.09 μm is deposited on top of the first gold layer. After the second gold layer is barrel plated, the second gold layer on the housing and leads is rinsed with tap water and deionized water in sequence. After rinsing, the housing and leads are removed and dried.

[0060] S6. Gold plating on the outer wall of the housing and the leads located outside the blind holes.

[0061] After electroplating the inner wall of blind hole 12 and the lead wire located inside blind hole 12 with gold layer 2, the thickness of the gold layer on the inner wall of blind hole 12 and the lead wire located inside blind hole 12 meets the required thickness. Therefore, subsequent electroplating does not require further electroplating of these two parts. This application uses a sealing clamp 4 to seal these two parts to prevent the electroplating solution from contacting the inner wall of blind hole 12 and the lead wire located inside blind hole 12 during subsequent electroplating, thereby better electroplating gold onto the outer wall of housing 1 and the lead wire outside blind hole 1. The sealing clamp 4 is made of Teflon, which was purchased from Shenzhen Jinruihuang Plastic Materials Co., Ltd. The sealing clamp 4 has acid and alkali resistance, cold and heat resistance, and is also elastic.

[0062] like Figure 2 , Figure 3As shown, the sealing clamp 4 includes a support plate 41, on which a plurality of electroplating holes 42 are provided. The diameter of the electroplating holes 42 gradually decreases from bottom to top. A plurality of lead wires 2 are installed on the housing 1, resulting in a plurality of blind holes 12. The plurality of electroplating holes 42 correspond to the plurality of lead wires 2. A boss 43 is provided on the support plate 41 above the electroplating holes 42. The radial diameter of the boss 43 is smaller than the diameter of the blind holes 12. A connecting hole 44 communicating with the electroplating holes 42 is provided on the boss 43. The diameter of the connecting hole 44 is smaller than the radial diameter of the lead wires 2. A guide hole 45 is provided at the top of the connecting hole 44. The guide hole 45 communicates with the connecting hole 44. The diameter of the guide hole 45 gradually decreases from top to bottom.

[0063] During installation, align the lead wire 2 with the corresponding guide hole 45, then insert the lead wire 2 into the corresponding connecting hole 44 and extend it out of the electroplating hole 42. The lead wire 2 and the corresponding connecting hole 44 are press-fitted, and the lower end face of the blind hole 12 is tightly attached to the upper surface of the support plate 41, thereby making the sealing clamp 4 stably engaged with the housing and the lead wire. The press-fit between the lead wire 2 and the corresponding connecting hole 44 can prevent the electroplating solution from contacting the lead wire in the blind hole during subsequent electroplating. The tight attachment of the lower end face of the blind hole 12 to the upper surface of the support plate 41 can prevent the electroplating solution from entering the blind hole 12 and contacting the inner wall of the blind hole 12 during subsequent electroplating.

[0064] After the sealing clamp 4 is attached to the housing and lead wire to form an assembly, the entire assembly is subjected to ultrasonic chemical degreasing. Then, the assembly is cleaned with tap water and deionized water in sequence. The cleaned assembly is then placed in an electrolyte for degreasing using electrolysis. After degreasing, the assembly is cleaned with tap water and deionized water in sequence. The cleaned assembly is then placed in a drum containing gold plating solution and rotated at 7 rpm for 2.5 minutes to perform horizontal barrel plating on the housing and the lead wire on the housing. This results in a gold layer of 0.2 μm thickness being electroplated on the outer wall of the housing and the lead wire outside the blind hole. After barrel plating the gold layer of 0.2 μm, the gold layer of 0.2 μm on the housing and the lead wire is cleaned with tap water and deionized water in sequence. After cleaning, the assembly is removed and dried.

[0065] S7, Gold-plated Leads

[0066] The assembly is mounted on the hanger with the large-diameter end of the electroplating hole 42 facing upwards. Then, the assembly is placed in the gold plating solution and electrodeposited for 6 minutes to deposit a fourth gold layer with a thickness of 2.5 mm on the lead wire located outside the blind hole. After depositing the fourth gold layer on the third gold layer, the fourth gold layer on the assembly is cleaned with tap water and deionized water in sequence. After cleaning, the sealing fixture is removed and the housing and lead wire are dried. After drying, it can enter the packaging stage. The cleaned sealing fixture can be recycled.

[0067] Example 2

[0068] A plating process for the metal package housing of a radio frequency interference filter includes the following steps:

[0069] S1. Cleaning and degreasing

[0070] S2, chemical polishing

[0071] S3, nickel plating layer

[0072] The housing and its leads are placed in a drum containing a nickel plating solution and rotated at 7.5 rpm for 5 minutes to perform horizontal barrel plating on the housing and its leads. This process deposits a nickel layer with a thickness of 3 μm on the outer wall of the housing, the inner wall of the blind holes, and the outer wall of the leads. After the nickel plating, the nickel layer on the housing and leads is rinsed with tap water and then with deionized water.

[0073] S4, Pre-plated gold

[0074] The shell with the nickel layer and the leads are placed in a drum containing a gold plating solution. The drum is rotated at 5 rpm for 1 minute to perform horizontal barrel plating on the shell and the leads on the shell, so that a gold layer with a thickness of 0.04 μm is deposited on the nickel layer.

[0075] S5, barrel-plated gold

[0076] The housing with the first gold layer deposited and the lead wires are placed into a drum containing a gold plating solution. The drum is rotated at 15 rpm for 1 minute to perform horizontal barrel plating on the housing and the lead wires, so that a second gold layer with a thickness of 0.1 μm is deposited on the first gold layer. After the second gold layer is barrel plated, the second gold layer on the housing and the lead wires is washed with tap water and deionized water in sequence. After washing, the housing and the lead wires on the housing are removed and dried.

[0077] S6. Gold plating on the outer wall of the housing and the leads located outside the blind holes.

[0078] After the inner wall of the blind hole 12 and the lead wire located inside the blind hole are electroplated with gold layer 2, the thickness of the gold layer on the inner wall of the blind hole 12 and the lead wire located inside the blind hole meets the required thickness. Therefore, in subsequent electroplating processes, it is not necessary to electroplat these two parts again. This application uses a sealing clamp 4 to seal these two parts to prevent the electroplating solution from contacting the inner wall of the blind hole 12 and the lead wire located inside the blind hole 12 during subsequent electroplating, thereby better electroplating gold on the outer wall of the housing 1 and the lead wire outside the blind hole 1.

[0079] After the sealing clamp 4 is attached to the housing and lead wire to form an assembly, the entire assembly is subjected to ultrasonic chemical degreasing. Then, the assembly is cleaned with tap water and deionized water in sequence. The cleaned assembly is then placed in an electrolyte for degreasing using electrolysis. After degreasing, the assembly is cleaned with tap water and deionized water in sequence. The cleaned assembly is then placed in a drum containing a gold plating solution and rotated at a speed of 5 rpm for 4 minutes to perform horizontal barrel plating on the housing and the lead wire on the housing. This results in a gold layer of 0.6 μm thickness being electroplated on the outer wall of the housing and the lead wire outside the blind hole. After barrel plating the gold layer of 0.6 μm, the gold layer of 0.6 μm on the housing and the lead wire is cleaned with tap water and deionized water in sequence. After cleaning, the assembly is removed and dried.

[0080] S7, Gold-plated Leads

[0081] The assembly is mounted on the hanger with the large-diameter end of the electroplating hole 42 facing upwards. Then, the assembly is placed in the gold plating solution and electrodeposited for 6 minutes to deposit a fourth gold layer with a thickness of 2.5 mm on the lead wire located outside the blind hole. After depositing the fourth gold layer on the third gold layer, the fourth gold layer on the assembly is cleaned with tap water and deionized water in sequence. After cleaning, the sealing fixture is removed and the housing and lead wire are dried. After drying, it can enter the packaging stage. The cleaned sealing fixture can be recycled.

[0082] Example 3

[0083] A plating process for the metal package housing of a radio frequency interference filter includes the following steps:

[0084] S1. Degreasing and cleaning; S2. Chemical polishing

[0085] S3, nickel plating layer

[0086] The housing and its leads are placed in a drum containing a nickel plating solution and rotated at 8 rpm for 7 minutes to perform horizontal barrel plating on the housing and its leads. This process deposits a nickel layer with a thickness of 4 μm on the outer wall of the housing, the inner wall of the blind holes, and the outer wall of the leads. After the nickel plating, the nickel layer on the housing and leads is rinsed with tap water and then with deionized water.

[0087] S4, Pre-plated gold

[0088] The shell with the nickel layer and the leads are placed in a drum containing a gold plating solution. The drum is rotated at 7 rpm for 0.7 minutes to perform horizontal barrel plating on the shell and the leads, so that a gold layer with a thickness of 0.03 μm is deposited on the nickel layer.

[0089] S5, barrel-plated gold

[0090] The housing with the first gold layer deposited and the lead wires are placed into a drum containing a gold plating solution. The drum is rotated at 10 rpm for 2 minutes to perform horizontal barrel plating on the housing and the lead wires, so that a second gold layer with a thickness of 0.12 μm is deposited on top of the first gold layer. After the second gold layer is barrel plated, the second gold layer on the housing and the lead wires is washed with tap water and deionized water in sequence. After washing, the housing and the lead wires are removed and dried.

[0091] S6. Gold plating on the outer wall of the housing and the leads located outside the blind holes.

[0092] After the inner wall of the blind hole 12 and the lead wire located inside the blind hole are electroplated with gold layer 2, the thickness of the gold layer on the inner wall of the blind hole 12 and the lead wire located inside the blind hole meets the required thickness. Therefore, in subsequent electroplating processes, it is not necessary to electroplat these two parts again. This application uses a sealing clamp 4 to seal these two parts to prevent the electroplating solution from contacting the inner wall of the blind hole 12 and the lead wire located inside the blind hole 12 during subsequent electroplating, thereby better electroplating gold on the outer wall of the housing 1 and the lead wire outside the blind hole 1.

[0093] After the sealing clamp 4 is attached to the housing and lead wire to form an assembly, the entire assembly is subjected to ultrasonic chemical degreasing. Then, the assembly is cleaned with tap water and deionized water in sequence. The cleaned assembly is placed in an electrolyte for degreasing by electrolysis. After degreasing, the assembly is cleaned with tap water and deionized water in sequence. The cleaned assembly is placed in a drum containing gold plating solution and the drum is rotated at 10 rpm for 3 minutes to perform horizontal barrel plating on the housing and the lead wire on the housing. This results in a gold layer 3 being electroplated on the outer wall of the housing and the lead wire outside the blind hole. The thickness of the gold layer 3 is 0.5 μm. After barrel plating the gold layer 3, the gold layer 3 on the housing and the lead wire is cleaned with tap water and deionized water in sequence. After cleaning, the assembly is removed and dried.

[0094] S7, Gold-plated Leads

[0095] The assembly is mounted on the hanger with the electroplating hole 42 facing upwards. Then, the assembly is immersed in the gold plating solution and electrodeposited for 8 minutes to deposit a fourth gold layer on the lead wire outside the blind hole. The thickness of the fourth gold layer is 4.2 mm. After depositing the fourth gold layer on the third gold layer, the fourth gold layer on the assembly is cleaned with tap water and deionized water in sequence. After cleaning, the sealing fixture is removed, and the housing and lead wire are dried. After drying, it can enter the packaging stage. The cleaned sealing fixture can be recycled.

[0096] Example 4

[0097] A plating process for the metal package housing of a radio frequency interference filter includes the following steps:

[0098] S1. Cleaning and degreasing

[0099] S2, chemical polishing

[0100] S3, nickel plating layer

[0101] The housing and its leads are placed in a drum containing a nickel plating solution and rotated at 10 rpm for 5 minutes to perform horizontal barrel plating on the housing and its leads. This process deposits a nickel layer with a thickness of 3.5 μm on the outer wall of the housing, the inner wall of the blind holes, and the outer wall of the leads. After the nickel plating, the nickel layer on the housing and leads is rinsed with tap water and then with deionized water.

[0102] S4, Pre-plated gold

[0103] The shell with the nickel layer and the leads are placed in a drum containing a gold plating solution. The drum is rotated at 12 rpm for 0.55 minutes to perform horizontal barrel plating on the shell and the leads, so that a gold layer with a thickness of 0.02 μm is deposited on the nickel layer.

[0104] S5, barrel-plated gold

[0105] The housing with the first gold layer deposited and the leads are placed in a drum containing a gold plating solution. The drum is rotated at 7.5 rpm for 1.6 minutes to perform horizontal barrel plating on the housing and the leads, so that a second gold layer with a thickness of 0.15 μm is deposited on top of the first gold layer. After the second gold layer is barrel plated, the second gold layer on the housing and leads is rinsed with tap water and deionized water in sequence. After rinsing, the housing and the leads are removed and dried.

[0106] S6. Gold plating on the outer wall of the housing and the leads located outside the blind holes.

[0107] After the inner wall of the blind hole 12 and the lead wire located inside the blind hole are electroplated with gold layer 2, the thickness of the gold layer on the inner wall of the blind hole 12 and the lead wire located inside the blind hole meets the required thickness. Therefore, in subsequent electroplating processes, it is not necessary to electroplat these two parts again. This application uses a sealing clamp 4 to seal these two parts to prevent the electroplating solution from contacting the inner wall of the blind hole 12 and the lead wire located inside the blind hole 12 during subsequent electroplating, thereby better electroplating gold on the outer wall of the housing 1 and the lead wire outside the blind hole 1.

[0108] After the sealing clamp 4 is attached to the housing and lead wire to form an assembly, the entire assembly is subjected to ultrasonic chemical degreasing. Then, the assembly is cleaned with tap water and deionized water in sequence. The cleaned assembly is then placed in an electrolyte for degreasing by electrolysis. After degreasing, the assembly is cleaned with tap water and deionized water in sequence. The cleaned assembly is then placed in a drum containing gold plating solution and rotated at 12 rpm for 3.5 minutes to perform horizontal barrel plating on the housing and the lead wire on the housing. This results in a gold layer 3 being electroplated on the outer wall of the housing and the lead wire outside the blind hole. The thickness of the gold layer 3 is 0.3 μm. After barrel plating the gold layer 3, the gold layer 3 on the housing and the lead wire is cleaned with tap water and deionized water in sequence. After cleaning, the assembly is removed and dried.

[0109] S7, Gold-plated Leads

[0110] The assembly is mounted on the hanger with the electroplating hole 42 facing upwards. Then, the assembly is immersed in the gold plating solution and electrodeposited for 7 minutes to deposit a fourth gold layer with a thickness of 3.5 mm on the lead wire located outside the blind hole. After depositing the fourth gold layer on the third gold layer, the fourth gold layer on the assembly is cleaned with tap water and deionized water in sequence. After cleaning, the sealing fixture is removed, and the housing and lead wire are dried. After drying, it can enter the packaging stage. The cleaned sealing fixture can be recycled.

[0111] Example 5

[0112] A plating process for the metal package housing of a radio frequency interference filter includes the following steps:

[0113] S1. Cleaning and degreasing

[0114] S2, chemical polishing

[0115] S3, nickel plating layer

[0116] The housing and its leads are placed in a drum containing a nickel plating solution and rotated at 12 rpm for 15 minutes to perform horizontal barrel plating on the housing and its leads. This process deposits a nickel layer with a thickness of 5 μm on the outer wall of the housing, the inner wall of the blind holes, and the outer wall of the leads. After the nickel plating, the nickel layer on the housing and leads is rinsed with tap water and deionized water in sequence.

[0117] S4, Pre-plated gold

[0118] The shell with the nickel layer and the leads are placed in a drum containing a gold plating solution. The drum is rotated at 15 rpm for 0.6 minutes to perform horizontal barrel plating on the shell and the leads, so that a gold layer with a thickness of 0.02 μm is deposited on the nickel layer.

[0119] S5, barrel-plated gold

[0120] The housing with the first gold layer deposited and the leads are placed in a drum containing a gold plating solution. The drum is rotated at 8 rpm for 1.8 minutes to perform horizontal barrel plating on the housing and the leads, so that a second gold layer with a thickness of 0.13 μm is deposited on top of the first gold layer. After the second gold layer is barrel plated, the second gold layer on the housing and leads is rinsed with tap water and deionized water in sequence. After rinsing, the housing and the leads are removed and dried.

[0121] S6. Gold plating on the outer wall of the housing and the leads located outside the blind holes.

[0122] After the inner wall of the blind hole 12 and the lead wire located inside the blind hole are electroplated with gold layer 2, the thickness of the gold layer on the inner wall of the blind hole 12 and the lead wire located inside the blind hole meets the required thickness. Therefore, in subsequent electroplating processes, it is not necessary to electroplat these two parts again. This application uses a sealing clamp 4 to seal these two parts to prevent the electroplating solution from contacting the inner wall of the blind hole 12 and the lead wire located inside the blind hole 12 during subsequent electroplating, thereby better electroplating gold on the outer wall of the housing 1 and the lead wire outside the blind hole 1.

[0123] After the sealing clamp 4 is attached to the housing and lead wire to form an assembly, the entire assembly is subjected to ultrasonic chemical degreasing. Then, the assembly is cleaned with tap water and deionized water in sequence. The cleaned assembly is placed in an electrolyte for degreasing by electrolysis. After degreasing, the assembly is cleaned with tap water and deionized water in sequence. The cleaned assembly is placed in a drum containing gold plating solution and the drum is rotated at 15 rpm for 3 minutes to perform horizontal barrel plating on the housing and the lead wire on the housing. This results in the electroplating of a third gold layer with a thickness of 0.4 μm on the outer wall of the housing and the lead wire outside the blind hole. After barrel plating the third gold layer, the third gold layer on the housing and the lead wire is cleaned with tap water and deionized water in sequence. After cleaning, the assembly is removed and dried.

[0124] S7, Gold-plated Leads

[0125] The assembly is mounted on the hanger with the electroplating hole 42 facing upwards. Then, the assembly is immersed in the gold plating solution and electrodeposited for 6.5 minutes to deposit a fourth gold layer with a thickness of 3mm on the lead wire located outside the blind hole. After depositing the fourth gold layer on the third gold layer, the fourth gold layer on the assembly is cleaned with tap water and deionized water in sequence. After cleaning, the sealing fixture is removed, and the housing and lead wire are dried. After drying, it can enter the packaging stage. The cleaned sealing fixture can be recycled.

[0126] Example 6

[0127] A plating process for the metal package housing of a radio frequency interference filter includes the following steps:

[0128] S1. Cleaning and degreasing

[0129] S2, chemical polishing

[0130] S3, nickel plating layer

[0131] The housing and its leads are placed in a drum containing a nickel plating solution and rotated at 15 rpm for 10 minutes to perform horizontal barrel plating on the housing and its leads. This process deposits a nickel layer with a thickness of 4.2 μm on the outer wall of the housing, the inner wall of the blind holes, and the outer wall of the leads. After the nickel plating, the nickel layer on the housing and leads is rinsed with tap water and then with deionized water.

[0132] S4, Pre-plated gold

[0133] The shell with the nickel layer and the leads are placed in a drum containing a gold plating solution. The drum is rotated at 8 rpm for 0.85 minutes to perform horizontal barrel plating on the shell and the leads on the shell, so that a gold layer with a thickness of 0.05 μm is deposited on the nickel layer.

[0134] S5, barrel-plated gold

[0135] The housing with the first gold layer deposited and the leads are placed into a drum containing a gold plating solution. The drum is rotated at 12 rpm for 1 minute to perform horizontal barrel plating on the housing and leads, so that a second gold layer with a thickness of 0.1 μm is deposited on top of the first gold layer. After the second gold layer is barrel plated, the second gold layer on the housing and leads is rinsed with tap water and deionized water in sequence. After rinsing, the housing and leads are removed and dried.

[0136] S6. Gold plating on the outer wall of the housing and the leads located outside the blind holes.

[0137] After the inner wall of the blind hole 12 and the lead wire located inside the blind hole are electroplated with gold layer 2, the thickness of the gold layer on the inner wall of the blind hole 12 and the lead wire located inside the blind hole meets the required thickness. Therefore, in subsequent electroplating processes, it is not necessary to electroplat these two parts again. This application uses a sealing clamp 4 to seal these two parts to prevent the electroplating solution from contacting the inner wall of the blind hole 12 and the lead wire located inside the blind hole 12 during subsequent electroplating, thereby better electroplating gold on the outer wall of the housing 1 and the lead wire outside the blind hole 1.

[0138] After the sealing clamp 4 is attached to the housing and lead wire to form an assembly, the entire assembly is subjected to ultrasonic chemical degreasing. Then, the assembly is cleaned with tap water and deionized water in sequence. The cleaned assembly is placed in an electrolyte for degreasing by electrolysis. After degreasing, the assembly is cleaned with tap water and deionized water in sequence. The cleaned assembly is placed in a drum containing gold plating solution and the drum is rotated at 10 rpm for 4 minutes to perform horizontal barrel plating on the housing and the lead wire on the housing. This results in the electroplating of a third gold layer with a thickness of 0.3 μm on the outer wall of the housing and the lead wire outside the blind hole. After barrel plating the third gold layer, the third gold layer on the housing and the lead wire is cleaned with tap water and deionized water in sequence. After cleaning, the assembly is removed and dried.

[0139] S7, Gold-plated Leads

[0140] The assembly is mounted on the hanger with the electroplating hole 42 facing upwards. Then, the assembly is immersed in the gold plating solution and electrodeposited for 6.5 minutes to deposit a fourth gold layer with a thickness of 3mm on the lead wire located outside the blind hole. After depositing the fourth gold layer on the third gold layer, the fourth gold layer on the assembly is cleaned with tap water and deionized water in sequence. After cleaning, the sealing fixture is removed, and the housing and lead wire are dried. After drying, it can enter the packaging stage. The cleaned sealing fixture can be recycled.

[0141] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A plating process for a metal-encased housing of a radio frequency interference filter, characterized in that, Includes the following steps: S1. Electroplating nickel layer on the outer wall of the housing, the inner wall of the blind hole, and the lead wire; S2. Electroplating a gold layer one on the nickel layer, the thickness of the gold layer one being 0.01~0.05um; S3. Electroplating a second gold layer on the first gold layer, the thickness of the second gold layer being 0.09–0.15 μm; S4. Gold layer three is electroplated on the outer wall of the shell and on the lead wire located outside the blind hole. Gold layer three is deposited on gold layer two and the thickness of gold layer three is 0.2~0.6um. S5. A fourth gold layer is electroplated on the lead located outside the blind via. The fourth gold layer is deposited on the third gold layer, and the thickness of the fourth gold layer is 2.5–4.2 μm. Step S4, before the third gold plating layer, also includes sealing the inner wall of the blind hole and the lead wire located in the blind hole; sealing is performed using a sealing clamp made of Teflon, the sealing clamp is provided with a connecting hole, the diameter of the connecting hole is smaller than the radial diameter of the lead wire, when the sealing clamp is engaged with the lead wire, the lower end face of the blind hole is tightly attached to the sealing clamp.

2. The plating process of a metal-encased housing of a radio frequency interference filter according to claim 1, wherein, Before step S1, the housing and leads are also subjected to cleaning, degreasing, and chemical polishing.

3. The plating process for a radio frequency interference filter's metal-encased housing of claim 1, wherein, In step S1, a nickel layer is electroplated on the outer wall of the shell, the inner wall of the blind hole, and the lead wire using a horizontal barrel plating method. The thickness of the nickel layer is 3-5 μm.

4. The plating process for a radio frequency interference filter's metal-encased housing of claim 1, wherein, In step S2, the first gold plating layer is deposited using a horizontal barrel plating method. The shell and leads with the nickel layer deposited are placed into a barrel containing the gold plating solution. The barrel rotates at a speed of 5 to 15 revolutions per minute for 0.5 to 1 minute, so that the first gold layer is deposited on the nickel layer.

5. The plating process for the metal packaging shell of the radio frequency interference filter according to claim 1, characterized in that, In step S3, the second gold plating layer is deposited using a horizontal barrel plating method. The shell with the first gold layer and the lead wire are placed into a barrel containing a gold plating solution. The barrel rotates at a speed of 5 to 15 revolutions per minute for 1 to 2 minutes, so that the second gold layer is deposited on the first gold layer.

6. The plating process for a radio frequency interference filter's metal-encased housing of claim 1, wherein, The sealing clamp includes a support plate with electroplating holes. Above the electroplating holes, the support plate has a boss that can be embedded in a blind hole. The boss has a connecting hole that communicates with the electroplating holes.

7. The plating process for a radio frequency interference filter metal-enclosed housing as recited in claim 6, wherein, A guide hole is provided on the connection hole.

8. The plating process for a radio frequency interference filter's metal-encased housing of claim 1, wherein, In step S5, the fourth electroplated gold layer is applied using a rack plating method.

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