CN114406391A - Welding method for aluminum-based flexible circuit board and component - Google Patents
Welding method for aluminum-based flexible circuit board and component Download PDFInfo
- Publication number
- CN114406391A CN114406391A CN202210198753.2A CN202210198753A CN114406391A CN 114406391 A CN114406391 A CN 114406391A CN 202210198753 A CN202210198753 A CN 202210198753A CN 114406391 A CN114406391 A CN 114406391A
- Authority
- CN
- China
- Prior art keywords
- aluminum
- circuit board
- flexible circuit
- based flexible
- component
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K1/00—Soldering, e.g. brazing, or unsoldering
- B23K1/005—Soldering by means of radiant energy
- B23K1/0056—Soldering by means of radiant energy soldering by means of beams, e.g. lasers, E.B.
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K3/00—Apparatus or processes for manufacturing printed circuits
- H05K3/30—Assembling printed circuits with electric components, e.g. with resistor
- H05K3/32—Assembling printed circuits with electric components, e.g. with resistor electrically connecting electric components or wires to printed circuits
- H05K3/34—Assembling printed circuits with electric components, e.g. with resistor electrically connecting electric components or wires to printed circuits by soldering
- H05K3/341—Surface mounted components
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Mechanical Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Electric Connection Of Electric Components To Printed Circuits (AREA)
Abstract
The invention discloses a method for welding an aluminum-based flexible circuit board and a component, which comprises the following steps: carrying out surface treatment on the original aluminum-based flexible circuit board to obtain a treated aluminum-based flexible circuit board; pre-coating tin-based solder on the treated aluminum-based flexible circuit board to obtain a target aluminum-based flexible circuit board; and carrying out laser soldering on the target aluminum-based flexible circuit board and the component to be soldered to complete soldering. The influence of an oxide film on the surface of the aluminum-based flexible circuit board is removed through surface treatment, and the wettability of the joint is improved; by pre-coating tin-based brazing filler metal and introducing a laser soldering method, the problems of long welding time, low efficiency and high energy consumption caused by reflow soldering are solved on the basis of ensuring that the micron-sized aluminum substrate and the copper-based component are effectively connected, the pressure sensitivity and the temperature sensitivity in the traditional welding method are overcome, the high-efficiency and high-quality connection of the aluminum-based flexible circuit board and the component is realized, and the aluminum-based flexible circuit board can be further popularized and applied.
Description
Technical Field
The invention relates to the field of electronic packaging and automobiles, in particular to a method for welding an aluminum-based flexible circuit board and a component.
Background
Copper-based Circuit boards (including a PCB and a FPCB) are mostly used in the traditional FPC (Flexible Printed Circuit) industry, but since aluminum has the obvious advantages of good electrical conductivity, thermal conductivity, light weight (30% of copper) and low cost (1/6 of copper), the weight of the whole automobile can be effectively reduced while the cost is greatly reduced, and finally the fuel economy is improved and the emission is reduced, so that the carbon emission reduction is realized. Therefore, in the application of the automobile industry, particularly in the new energy electrodynamic force automobile industry, the aluminum substrate is expected to replace the traditional copper-based circuit board, so that the production cost is greatly reduced, the endurance mileage is increased, and the energy consumption is reduced.
In the prior art, in the first aspect, the technology of soldering components (the pins or the solder joints of which are mostly copper-based) on the surface of the pad of the conventional copper-based flexible circuit board is very mature (mainly adopting reflow soldering). However, the number of components (solder joint area) to be connected on the surface of the vehicle-mounted circuit board is very small compared with the area of the whole circuit board, and the reflow soldering method brings about the problems of long soldering time, low efficiency and energy waste. Therefore, the reflow soldering method is not recommended to be applied to soldering of an aluminum-based flexible wiring board and a copper-based component.
In the second aspect, when the copper substrate is replaced with the aluminum substrate, aluminum oxide (Al) is present on the surface of the aluminum substrate2O3) The oxide film is difficult to remove, and the aluminum-based flexible circuit board and the tin-based solder are difficult to wet to form a good welding joint due to the compact high-melting-point aluminum oxide film. In order to improve the wettability of the joint, the prior art mainly utilizes a chemical reaction welding method, and the method adopts NaOH solution to remove Al on the surface of an aluminum substrate by alkaline etching2O3Oxidizing the film and then using HNO3Passivating its surface at HNO3After passivation, the solder paste is applied immediately and then reflow soldered, thus minimizing Al2O3The thickness of the oxide film, and the addition of Zn, Ga, Na and the like in the solder paste enables the solder paste to be alloyed, so that the wettability of the joint can be effectively improved. However, this method requires addition of alloying elements and Al2O3The oxide film could not be completely removed, and Al remained in the local region2O3The method is still adopted for the traditional reflow soldering, so the efficiency is not improved, and the method is not suitable for soldering of an aluminum-based flexible circuit board and a copper-based component.
In the third aspect, the welding of the aluminum-based flexible circuit board and the copper-based component is actually the connection problem of micron-sized copper and aluminum, and the connection method of micron-sized copper and aluminum reported in advanced documents and technologies mainly comprises solid-phase welding (including methods such as friction stir welding and ultrasonic welding) and nano-laser welding. Aiming at solid phase welding, such as ultrasonic welding, the method uses ultrasonic waves to break an oxide film on the surface of an aluminum substrate to form connection, but the aluminum substrate is millimeter-sized, the thickness of a flexible circuit board is micron-sized and is extremely sensitive to pressure, and due to the size effect (less than 100 mu m) of the aluminum-based flexible circuit board and components, the problems that tooling is difficult, the circuit board is easily damaged by high pressure and the like are difficult to solve in the actual operation process. Therefore, the method is not suitable for welding the aluminum-based flexible circuit board and the copper-based component. Aiming at nano laser welding, the micron-sized aluminum substrate and the copper plate can be effectively connected, but based on the characteristic of high energy density of nano laser, the welding joint can inevitably have the defect formed after laser ablation, so that the service safety performance of the flexible circuit board can be greatly reduced, and the application to welding of the aluminum-based flexible circuit board and the copper-based component is not recommended.
In conclusion, how to realize the high-efficiency and high-quality connection of the aluminum-based flexible circuit board and the component is a neck clamping problem which restricts the further popularization and application of the aluminum-based flexible circuit board.
Disclosure of Invention
In view of this, the embodiment of the present invention provides a method for welding an aluminum-based flexible circuit board and a component, so as to solve the problems in the prior art that an oxide film appearing on the surface of the aluminum-based flexible circuit board hinders reaction wetting of the aluminum-based flexible circuit board and a solder, high temperature sensitivity and pressure sensitivity of the aluminum-based flexible circuit board during a welding process, and long welding time, low efficiency, high energy consumption and the like caused by adopting a conventional reflow welding method, and can realize efficient and high-quality connection between the aluminum-based flexible circuit board and the component, so that the aluminum-based flexible circuit board can be further popularized and applied.
The embodiment of the invention provides a method for welding an aluminum-based flexible circuit board and a component, which comprises the following steps:
carrying out surface treatment on the original aluminum-based flexible circuit board to obtain a treated aluminum-based flexible circuit board;
pre-coating tin-based brazing filler metal on the treated aluminum-based flexible circuit board to obtain a target aluminum-based flexible circuit board;
and carrying out laser soldering on the target aluminum-based flexible circuit board and the component to be welded to finish welding.
Optionally, the surface treatment of the original aluminum-based flexible circuit board includes:
sequentially carrying out oil removal treatment and alkaline etching treatment on the original aluminum-based flexible circuit board to obtain a first aluminum-based flexible circuit board;
and cleaning the first aluminum-based flexible circuit board by adopting purified water to obtain a second aluminum-based flexible circuit board.
Optionally, after the first aluminum-based flexible circuit board is cleaned, the method further includes:
chemically zincating the second aluminum-based flexible circuit board to obtain a third aluminum-based flexible circuit board;
and carrying out nickel plating on the third aluminum-based flexible circuit board to obtain the treated aluminum-based flexible circuit board.
Optionally, the nickel plating has a thickness in the range of 4 to 7 μm.
Optionally, the nickel plating has a thickness in the range of 5 to 6 μm.
Optionally, before pre-coating the tin-based solder on the processed aluminum-based flexible circuit board, the method further comprises:
carrying out ultrasonic cleaning on the aluminum-based flexible circuit board to be treated;
and carrying out air drying treatment on the aluminum-based flexible circuit board after ultrasonic cleaning.
Optionally, the thickness of the tin-based solder ranges from 15 to 20 μm.
Optionally, the laser soldering the target aluminum-based flexible circuit board and the component to be soldered includes:
fixing the target aluminum-based flexible circuit board;
placing the pin of the component to be welded above the fixed target aluminum-based flexible circuit board, and fixing the component to be welded;
and welding the fixed target aluminum-based flexible circuit board and the fixed pin of the component to be welded by adopting laser soldering equipment.
Optionally, a laser spot emitted by the laser welding device coincides with the center of the pin of the component to be welded.
Optionally, the diameter range of the welding wire provided by the laser welding equipment is 0.3-0.6 mm.
Optionally, in soldering the target aluminum-based flexible circuit board and the pin of the component to be soldered, the method further includes:
detecting the welding temperature between the target aluminum-based flexible circuit board and the pin of the component to be welded in real time by adopting infrared temperature detection equipment; wherein the welding temperature is less than 500 ℃.
The invention has the beneficial effects that:
by carrying out surface treatment on the original aluminum-based flexible circuit board, on one hand, the influence of an oxide film on the surface of the aluminum-based flexible circuit board can be removed, so that the phenomenon that the oxide film obstructs reaction wetting of the aluminum-based flexible circuit board and brazing filler metal is avoided, the wettability of a joint is improved, and on the other hand, the adoption of a traditional reflow soldering method can be avoided, and the high efficiency of soldering is ensured; the tin-based solder is pre-coated on the aluminum-based flexible circuit board to be treated, so that the tin-based solder can be conveniently melted and forms good metallurgical bonding with a copper pin and a nickel layer of a component respectively, and the high-efficiency and high-quality connection of the aluminum-based flexible circuit board and the copper-based component is realized; on the basis of tin-based solder, a laser soldering method is introduced in the welding of a target aluminum-based flexible circuit board and a component to be welded, on the basis of ensuring that a micron-sized aluminum substrate and a copper-based component are effectively connected, the problems of long welding time, low efficiency and high energy consumption caused by reflow soldering can be solved, the production cost is further reduced, and the achievement of carbon peak reaching and carbon neutralization is promoted; on one hand, the pressure sensitivity in the traditional solid-phase welding method can be avoided, the phenomena of difficult tooling, high pressure, easy damage to a circuit board and the like can be avoided, on the other hand, the temperature sensitivity in the traditional nano laser welding method can be overcome, and the service safety performance of the flexible circuit board can not be reduced due to the defect of laser ablation formation;
by the welding method of the aluminum-based flexible circuit board and the component, the problems that in the prior art, an oxide film on the surface of the aluminum-based flexible circuit board hinders reaction wetting of the aluminum-based flexible circuit board and a brazing filler metal, the aluminum-based flexible circuit board has high temperature sensitivity and pressure sensitivity in the welding process, and the traditional reflow welding method is adopted to bring about long welding time, low efficiency, high energy consumption and the like can be effectively solved, and the aluminum-based flexible circuit board can be efficiently and excellently connected with the component, so that the aluminum-based flexible circuit board can be further popularized and applied.
Drawings
The features and advantages of the present invention will be more clearly understood by reference to the accompanying drawings, which are illustrative and not to be construed as limiting the invention in any way, and in which:
fig. 1 shows a flow chart of a method for welding an aluminum-based flexible circuit board and a component in an embodiment of the invention;
FIG. 2 shows a flow chart for obtaining a process for treating an aluminum-based flexible wiring board in an embodiment of the present invention;
FIG. 3 shows a flow chart of steps prior to pre-tinning solder on an aluminum-based flexible wiring board in an embodiment of the present invention;
FIG. 4-1 shows an SEM surface topography of a target aluminum-based flexible circuit board in an embodiment of the invention;
FIG. 4-2 shows an enlarged view of the dashed box portion of FIG. 4-1;
FIG. 5 is a cross-sectional view showing a structure model of a target aluminum-based flexible wiring board according to an embodiment of the present invention;
FIG. 6 shows a flow chart of laser soldering of a target aluminum-based flexible circuit board and a component to be soldered in an embodiment of the present invention;
fig. 7 shows a schematic diagram of a laser soldering method according to an embodiment of the present invention.
The reference numerals are explained below:
100. the method comprises the following steps of preparing a target aluminum-based flexible circuit board, 110, an original aluminum-based flexible circuit board, 120, a nickel layer, 130, tin-based solder, 200, a component to be welded, 210, a copper pin, 300, laser welding equipment, 310, a laser, 311, a laser spot, 320, a wire feeder, 321 and welding wires.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The embodiment of the invention provides a welding method of an aluminum-based flexible circuit board and a component, as shown in figure 1, the welding method comprises the following steps:
s10, carrying out surface treatment on the original aluminum-based flexible circuit board to obtain a treated aluminum-based flexible circuit board;
s20, pre-coating tin-based solder on the processed aluminum-based flexible circuit board to obtain a target aluminum-based flexible circuit board;
and S30, performing laser soldering on the target aluminum-based flexible circuit board and the component to be soldered to complete soldering.
Specifically, in this embodiment S10, an aluminum-based flexible wiring board of 100 μm (in which the polyimide film is 20 μm thick) is selected as the original aluminum-based flexible wiring board for surface treatment.
Preferably, as shown in fig. 2, step S10 includes:
s101: sequentially carrying out oil removal treatment and alkaline etching treatment on the original aluminum-based flexible circuit board to obtain a first aluminum-based flexible circuit board;
s102: cleaning the first aluminum-based flexible circuit board by using purified water to obtain a second aluminum-based flexible circuit board;
s103: chemically zincating the second aluminum-based flexible circuit board to obtain a third aluminum-based flexible circuit board;
s104: and carrying out nickel plating on the third aluminum-based flexible circuit board to obtain the treated aluminum-based flexible circuit board.
The degreasing treatment and the alkaline etching treatment are sequentially carried out, so that a metal oxide film on the surface of the original aluminum-based flexible circuit board can be removed, the adverse effect caused by the inert metal oxide film is further avoided, and a welding joint with no defect and excellent performance can be formed between the component and the aluminum-based flexible circuit board; the alkaline solution remained on the surface of the first aluminum-based flexible circuit board can be cleaned by cleaning the purified water, and meanwhile, a water film is remained on the surface of the second aluminum-based flexible circuit board obtained after cleaning, so that the contact between the aluminum surface and the air can be isolated to the greatest extent to generate a new oxidation film; by chemical zinc dipping, the surface of the third aluminum-based flexible circuit board can be further ensured to be a Zn layer instead of Al2O3Oxide film of Al on the surface of the aluminum-based flexible wiring board2O3Oxide film is completely eliminated and a barrier layer is formed to prevent Al2O3The formation of the oxide film further effectively avoids the adverse effect brought by the metal oxide film; the nickel plating on the surface of the third aluminum-based flexible circuit board can ensure that the surface of the treated aluminum-based flexible circuit board finally obtained after surface treatment has good bonding force, and is beneficial to forming defect-free components and aluminum-based flexible circuit boardsAnd a weld joint having excellent properties.
Specifically, in this embodiment S101, alcohol or acetone is selected to perform oil removal treatment on the original aluminum-based flexible circuit board, and a 20% NaOH solution is selected to soak the original aluminum-based flexible circuit board after the oil removal treatment for 3 to 5min, so that the alkali etching treatment is completed, where the soaking time is 3 to 5 min. In this embodiment S102, after the original aluminum-based flexible printed circuit board is subjected to oil removal treatment and alkaline etching treatment, the obtained first aluminum-based flexible printed circuit board is immediately put into purified water, and can clean the 20% NaOH solution remaining on the surface, at this time, a water film remains on the surface of the aluminum-based flexible printed circuit board, which can isolate the aluminum surface from contacting with air to generate a new oxide film as much as possible. In this embodiment S103, when the second aluminum-based flexible printed circuit board obtained after cleaning is immediately placed in a zincate solution for chemical zincing, the concentration ratio of the zincate solution can be set and adjusted according to actual conditions.
The chemical reaction equation of chemical zinc dipping is as follows: 2Al +3Zn2+→3Zn+2Al3+。
Specifically, in this embodiment S104, the thickness of the nickel plating is in the range of 4 to 7 μm, and preferably, the thickness of the nickel plating is in the range of 5 to 6 μm.
And nickel plating is carried out according to the thickness range, so that on one hand, the Ni plating layer on the surface of the aluminum-based flexible circuit board can have good bonding force, and on the other hand, the cost increase caused by the Ni plating layer with large thickness can be avoided.
Preferably, as shown in fig. 3, before S20, the method further includes:
s201: carrying out ultrasonic cleaning on the aluminum-based flexible circuit board to be treated;
s202: and carrying out air drying treatment on the aluminum-based flexible circuit board after ultrasonic cleaning.
Specifically, in this embodiment S201, the aluminum-based flexible printed circuit board is subjected to ultrasonic cleaning with absolute ethanol, so that the integrity and cleanliness of the nickel film on the surface of the aluminum-based flexible printed circuit board can be ensured.
Specifically, in this embodiment S20, the thickness of the tin-based solder ranges from 15 μm to 20 μm.
In order to ensure that the aluminum-based flexible circuit board has certain rigidity, a layer of polyimide board (namely, a PI board) is often attached to the back surface of the aluminum-based flexible circuit board, and the tin-based solder with the thickness range can be used for ensuring that the tin-based solder can absorb heat radiated by laser so that the PI board is not discolored when the heat is transmitted to the PI board; on the other hand, the cost increase caused by the tin-based solder with large thickness can be avoided, the solidification nonuniformity of the solder and the laser radiation time can be avoided from being increased, and therefore the welding efficiency is ensured.
More specifically, the thickness of the nickel plating in this example was 5 μm, and the thickness of the tin-based solder SAC305 was 18 μm. As shown in fig. 4-1 and 4-2, fig. 4-1 is an SEM (scanning electron microscope) surface topography of the target aluminum-based flexible wiring board after being plated with a 5 μm nickel layer and an 18 μm tin-based solder, respectively, and fig. 4-2 is an enlarged view of a dashed frame in fig. 4-1. By observing the surface topography obtained by a scanning electron microscope, the nickel layer is evenly and smoothly distributed along the upper side of the aluminum after the nickel layer with the thickness of 5 mu m is plated, and the black nickel phenomenon does not occur. After the 18 mu m tin-based solder is plated, the whole tin layer consists of tin grains with different sizes and shapes, and the whole tin layer is uniformly and flatly distributed on the nickel layer without the defects of cracks, holes and the like.
A model diagram of the target aluminum-based flexible circuit board 100 obtained by performing surface treatment, nickel plating and tin-based solder plating on the present embodiment is shown in fig. 5, the surface of the original aluminum-based flexible circuit board 110 is plated with a nickel layer 120, and the nickel layer 120 is plated with a tin-based solder 130.
Preferably, as shown in fig. 6, S30 includes:
s301: fixing the target aluminum-based flexible circuit board;
s302: placing the pin of the component to be welded above the fixed target aluminum-based flexible circuit board, and fixing the component to be welded;
s303: and welding the fixed target aluminum-based flexible circuit board and the fixed pin of the component to be welded by adopting laser soldering equipment.
Specifically, a model diagram of laser welding in the present embodiment is shown in fig. 7, and in fig. 7, a laser soldering apparatus 300 is manufactured by dr. The laser 310 is a semiconductor laser, the full power is 60W, the wavelength is 970nm, and a laser spot 311 emitted by the semiconductor laser coincides with the center of the copper pin 210 of the component 200 to be welded. The wire feeder 320 provides a welding wire 321, wherein the welding wire is a tin-based welding wire, and the diameter range of the welding wire is 0.3-0.6 mm; more specifically, 0.3mm lead-free F3M 705(Sn-3Ag-0.5Cu) is selected as the tin-based welding wire. The wire feeder 320 is an existing wire feeder, and details thereof are not described herein.
A target aluminum-based flexible circuit board is fixed on a workbench by using a welding fixture, a component to be welded is a universal amplifier of 8-SOIC (0.154 and 3.90mm in width), a pin to be welded of the component to be welded is placed above the position of the pre-tinned solder of the target aluminum-based flexible circuit board and is fixed by using the welding fixture, and deviation in the welding process is prevented. The device to be welded generally has a plurality of pins which need to be welded with a target aluminum-based flexible circuit board, and in the welding process of each pin, a laser spot emitted by the laser welding equipment needs to be superposed with the center of the pin of the device to be welded, so that a good welding effect is ensured. Wherein, the welding fixture is the existing welding tool, and the specific details are not repeated here.
In the laser tin soldering process, the semiconductor laser starts radiation to perform heating and preheating treatment on the pin of the component to be soldered, then the tin-based welding wire is fed under the action of the wire feeder and is melted under the radiation of laser emitted by the semiconductor laser to form molten drops which fall on the copper pin of the component to be soldered, the tin-based welding wire is pumped back under the pumping back action of the wire feeder while the molten drops form drops, the semiconductor laser is simultaneously closed, and the soldering is completed.
In the laser soldering process, molten tin-based welding wires form molten drops and fall on the copper pins, heat is further transferred to tin-based brazing filler metal below the pins through heat conduction, the brazing filler metal is molten and forms good metallurgical bonding with the pins and the nickel layers respectively, and finally high-quality components and aluminum-based flexible circuit board welding joints can be obtained. The mechanical property of the obtained welding joint depends on the bonding capacity of the nickel layer and the aluminum-based flexible circuit board and the metallurgical bonding capacity formed by the melted welding wire, the nickel layer and the pins, the adverse effect caused by the inert oxide film on the surface of the aluminum-based flexible circuit board is fundamentally solved, and the welding joint with no defect and excellent performance can be formed by the components and the aluminum-based flexible circuit board.
Preferably, in S303, the method further includes:
detecting the welding temperature between the target aluminum-based flexible circuit board and the pin of the component to be welded in real time by adopting infrared temperature detection equipment; wherein the welding temperature is less than 500 ℃.
By detecting the welding temperature between the target aluminum-based flexible circuit board and the pin of the component to be welded in real time and requiring the welding temperature to be less than 500 ℃, the temperature bearing range of the PI board and the temperature sensitivity range of the whole aluminum-based flexible circuit board can be fully considered in the laser soldering process, and the defect caused by laser ablation is avoided, so that the service safety performance of the flexible circuit board is reduced.
In one embodiment, the entire laser welding process in S303 is divided into five steps. The first step is that laser starts to irradiate the copper pin of the element to be welded, and the temperature in the circular laser irradiation area is raised to T1 within 0.1 s; continuously irradiating laser to enable the holding time of the temperature in the circular laser irradiation area under T1 to be T1, and preheating; the third step is that the laser continues to be irradiated, and the temperature in the circular laser irradiation area is increased to the peak temperature T2 from T1 within T1; the fourth step is that the laser is continuously irradiated, so that the time for keeping the temperature in the circular laser irradiation area at T2 is T2, and meanwhile, the wire feeder starts to feed wires; the fifth step is that when the time reaches t3, the wire feeding is stopped and the laser stops irradiating to complete the welding. Through a plurality of tests, the PI board at the bottom of the aluminum-based flexible circuit board is easy to discolor due to the action of heat conduction when the peak temperature T2 is more than or equal to 500 ℃, as shown in the following table. Therefore, the welding temperature in the actual laser soldering process should be less than 500 ℃.
PI (polyimide) plate at bottom of aluminum-based flexible circuit board at different peak temperatures of meter
Specifically, in this embodiment S303, laser soldering is performed by selecting appropriate parameters, which include T1 ═ 140 ℃, T2 ═ 342 ℃, T1 ═ 0.1S, T2 ═ 0.36S, and T3 ═ 0.66S. Under the parameters, nickel and tin based solder are plated according to the steps of the invention, and the upper surface forming and cross section appearance of the laser tin soldering joint of the aluminum-based flexible circuit board and the component to be soldered are observed in a comparison way. The result shows that the tin-based solder without tin plating on the surface is not spread and connected to the periphery of the copper pin, but is solidified on the copper pin and condensed into a spherical shape, the copper pin is not effectively connected with the aluminum-based flexible circuit board, and the whole tin-based solder is agglomerated on the copper pin and is not completely spread and wetted; the tin-plated aluminum-based flexible circuit board is effectively connected with the component to be welded, and the whole tin-based brazing filler metal is not agglomerated and shrunk on the copper pins but is completely wetted and spread on the aluminum substrate and the copper pins.
Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations fall within the scope defined by the appended claims.
Claims (10)
1. A method for welding an aluminum-based flexible circuit board and a component is characterized by comprising the following steps:
carrying out surface treatment on the original aluminum-based flexible circuit board to obtain a treated aluminum-based flexible circuit board;
pre-coating tin-based brazing filler metal on the treated aluminum-based flexible circuit board to obtain a target aluminum-based flexible circuit board;
and carrying out laser soldering on the target aluminum-based flexible circuit board and the component to be welded to finish welding.
2. The method for welding the aluminum-based flexible circuit board and the component as claimed in claim 1, wherein the surface treatment of the original aluminum-based flexible circuit board comprises:
sequentially carrying out oil removal treatment and alkaline etching treatment on the original aluminum-based flexible circuit board to obtain a first aluminum-based flexible circuit board;
and cleaning the first aluminum-based flexible circuit board by adopting purified water to obtain a second aluminum-based flexible circuit board.
3. The method for soldering the aluminum-based flexible circuit board and the component as claimed in claim 2, further comprising, after the first aluminum-based flexible circuit board is cleaned:
chemically zincating the second aluminum-based flexible circuit board to obtain a third aluminum-based flexible circuit board;
and carrying out nickel plating on the third aluminum-based flexible circuit board to obtain the treated aluminum-based flexible circuit board.
4. The method for welding the aluminum-based flexible circuit board and the component as claimed in claim 3, wherein the thickness of the nickel plating is 5-6 μm.
5. A method for soldering an al-based flexible wiring board and a component as claimed in claim 1, wherein before the pre-application of the tin-based solder to the processed al-based flexible wiring board, the method further comprises:
carrying out ultrasonic cleaning on the aluminum-based flexible circuit board to be treated;
and carrying out air drying treatment on the aluminum-based flexible circuit board after ultrasonic cleaning.
6. The method for welding the aluminum-based flexible circuit board and the component as claimed in claim 1, wherein the thickness of the tin-based solder is in a range of 15 to 20 μm.
7. The method for welding the aluminum-based flexible circuit board and the component according to claim 1, wherein the laser soldering of the target aluminum-based flexible circuit board and the component to be welded comprises:
fixing the target aluminum-based flexible circuit board;
placing the pin of the component to be welded above the fixed target aluminum-based flexible circuit board, and fixing the component to be welded;
and welding the fixed target aluminum-based flexible circuit board and the fixed pin of the component to be welded by adopting laser soldering equipment.
8. The method for welding the aluminum-based flexible circuit board and the component as claimed in claim 7, wherein a laser spot emitted by the laser welding equipment coincides with the center of a pin of the component to be welded.
9. The welding method of the aluminum-based flexible circuit board and the component as claimed in claim 7, wherein the diameter range of the welding wire provided by the laser welding equipment is 0.3-0.6 mm.
10. The method for soldering the aluminum-based flexible circuit board and the component according to claim 7, wherein in soldering the target aluminum-based flexible circuit board and the pin of the component to be soldered, the method further comprises:
detecting the welding temperature between the target aluminum-based flexible circuit board and the pin of the component to be welded in real time by adopting infrared temperature detection equipment; wherein the welding temperature is less than 500 ℃.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210198753.2A CN114406391A (en) | 2022-03-02 | 2022-03-02 | Welding method for aluminum-based flexible circuit board and component |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210198753.2A CN114406391A (en) | 2022-03-02 | 2022-03-02 | Welding method for aluminum-based flexible circuit board and component |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114406391A true CN114406391A (en) | 2022-04-29 |
Family
ID=81261814
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210198753.2A Pending CN114406391A (en) | 2022-03-02 | 2022-03-02 | Welding method for aluminum-based flexible circuit board and component |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114406391A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117161497A (en) * | 2023-10-24 | 2023-12-05 | 无锡锐科光纤激光技术有限责任公司 | Double-beam laser scanning brazing method |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006206945A (en) * | 2005-01-27 | 2006-08-10 | Toyo Kohan Co Ltd | SURFACE-TREATED Al SHEET HAVING EXCELLENT SOLDERABILITY WITH LOW MELTING POINT |
| CN101771142A (en) * | 2010-02-10 | 2010-07-07 | 力佳电源科技(深圳)有限公司 | Tab material of flexible-packaging lithium battery as well as electroplating method and application method thereof |
| CN101930804A (en) * | 2008-12-01 | 2010-12-29 | 日立电线株式会社 | Surface-treated metal material and manufacturing method of the same |
| CN102065646A (en) * | 2011-01-18 | 2011-05-18 | 武汉正维电子技术有限公司 | Surface mount technology of ratio frequency power amplification mainboard |
| CN102943291A (en) * | 2012-10-18 | 2013-02-27 | 中国电子科技集团公司第十研究所 | Surface treatment method for weldability and protectivity of aluminium alloy tube shell |
-
2022
- 2022-03-02 CN CN202210198753.2A patent/CN114406391A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006206945A (en) * | 2005-01-27 | 2006-08-10 | Toyo Kohan Co Ltd | SURFACE-TREATED Al SHEET HAVING EXCELLENT SOLDERABILITY WITH LOW MELTING POINT |
| CN101930804A (en) * | 2008-12-01 | 2010-12-29 | 日立电线株式会社 | Surface-treated metal material and manufacturing method of the same |
| CN101771142A (en) * | 2010-02-10 | 2010-07-07 | 力佳电源科技(深圳)有限公司 | Tab material of flexible-packaging lithium battery as well as electroplating method and application method thereof |
| CN102065646A (en) * | 2011-01-18 | 2011-05-18 | 武汉正维电子技术有限公司 | Surface mount technology of ratio frequency power amplification mainboard |
| CN102943291A (en) * | 2012-10-18 | 2013-02-27 | 中国电子科技集团公司第十研究所 | Surface treatment method for weldability and protectivity of aluminium alloy tube shell |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117161497A (en) * | 2023-10-24 | 2023-12-05 | 无锡锐科光纤激光技术有限责任公司 | Double-beam laser scanning brazing method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP0875331B1 (en) | Method of bonding an electronic part to a substrate. | |
| CN1245857C (en) | Circuit board and mounting method for the same, and electronic apparatus using the same | |
| CN102114561B (en) | Method of pre-copper-plated induction welding-brazing of aluminum-steel stud bolt | |
| JP5392463B2 (en) | Heat conduction member for solder handling machine, electric soldering iron and electric desoldering tool provided with the heat conduction member | |
| CN110449683B (en) | High-reliability printed circuit board assembly QFN (quad Flat No lead) assembling and welding pretreatment method | |
| CN113068324A (en) | Method for manufacturing circuit board by using remelting solder as weldability protective layer | |
| CN1301173C (en) | Return soldering method | |
| CN110666281B (en) | Brazing welding method for aluminum target and copper-containing back plate | |
| CN114406391A (en) | Welding method for aluminum-based flexible circuit board and component | |
| CN1253932C (en) | Semiconductor device and manufacture thereof, electronic machine | |
| CN111785644A (en) | Method for preparing pre-welded copper-clad ceramic substrate through laser cladding | |
| CN1817071A (en) | Reflow soldering method using pb-free solder alloy and hybrid packaging method and structure | |
| CN111112842A (en) | Gold-removing tin-coating method and application | |
| JPH02256249A (en) | Circuit substrate and method of its surface treatment | |
| Dušek et al. | Overview of selected issues related to soldering | |
| CN113695695A (en) | Method for soldering tin paste for semiconductor chip | |
| CN108672867B (en) | Fluxing agent-free pulse ultrasonic low-temperature brazing method for copper-based material | |
| US20060086718A1 (en) | Soldering method and device | |
| CN112820652B (en) | Method for removing Jin Tang tin from L-shaped welding terminal of QFN packaging device | |
| CN1066373C (en) | Method for dry fluxing of metallic surface, before soldering or tinning, using atmosphere which includes water vapour | |
| JP4599929B2 (en) | Method for manufacturing power semiconductor device | |
| US10933675B2 (en) | Aluminum based solderable contact | |
| JP2010051989A (en) | Laser joining method | |
| CN114434042A (en) | Solder powder for copper-aluminum interconnection and welding process | |
| CN100346679C (en) | Circuit board, electronic equipment using the circuit board and method of sorting circuit board |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |