A surface treatment device and method for improving the corrosion resistance of a tin-based coating or tin-based alloy

Abstract

The present invention relates to the technical field of metal corrosion and surface treatment, and particularly relates to a surface treatment device and method for improving the corrosion resistance of a tin-based coating or a tin-based alloy. The surface treatment device includes a chamber, a temperature control component, a humidity control component, an ultraviolet generator, and a power supply. The chamber has a treatment cavity and a transfer channel. The temperature control component is used to adjust the temperature in the treatment cavity; the humidity control component is used to adjust the humidity in the treatment cavity; the treatment cavity is used to provide a treatment environment required by the surface treatment process; the transfer channel is used to send in / out the tin-based coating or tin-based alloy to be treated into / from the treatment cavity; the ultraviolet generator is used to provide the ultraviolet rays required by the surface treatment process and is electrically connected to the power supply. During surface treatment, the tin-based coating or tin-based alloy is exposed in the treatment cavity, and the surface to be treated is placed face to face with the ultraviolet generator. The present invention is applicable to the corrosion resistance treatment of the surface of a tin-based coating or a tin-based alloy, with simple process, environmental protection and no pollution, stable treatment effect, and strong operability.

Description

Technical Field

[0001] The present invention relates to the technical field of metal corrosion and surface treatment, and particularly to a surface treatment device and method for improving the corrosion resistance of a tin-based coating or tin-based alloy. Background Art

[0002] China is the country with the largest proven reserves of tin ore in the world, with proven reserves of 26 million tons, accounting for 1 / 4 of the world's proven reserves. Tin has the characteristics of relatively soft texture, low melting point, strong plasticity, and very good malleability, and is widely used in industries such as electronics, information, electrical appliances, chemical engineering, metallurgy, building materials, machinery, and food packaging. Specifically, it is mainly used to manufacture tin-based coatings or tin-based alloys:

[0003] (1) For the preparation of tin foil, tinplate, pure tin or tin-based alloy coatings. Tin foil is mainly used in fields such as medicine, chemical engineering, light industry, food, art supplies, and handicraft production; Tinplate (also known as tinplate) refers to cold-rolled thin steel plates with a very thin layer of metallic tin plated on both sides. It combines the hardness and strength of steel with the weldability, corrosion resistance, and bright appearance of tin, and has the advantages of being odorless, non-toxic, lightweight, and easy to process and form. It has been widely used in industries such as the food canning industry, electronic devices, and chemical paints; In addition, with the rapid development of the electronics industry, metallic tin is widely used to make binary or multi-component solderable coatings based on tin, mainly including bright pure tin coatings, tin-lead alloys, and binary coatings such as tin-cerium, tin-antimony, tin-bismuth, and tin-indium.

[0004] (2) For the preparation of tin-based alloys or lead-free tin-based solders. Metallic tin is also widely used to prepare tin-based alloys. For example, tin-antimony-copper alloy is mainly used for bearings operating under high-speed and heavy-load conditions; The tin-based bearing alloy in Babbitt alloy is the most well-known bearing material and is widely used in large marine diesel engines, turbines, alternators, and other mining machinery and large rotating machinery; Furthermore, metallic tin is also widely used to manufacture lead-free tin-based solders, such as Sn-Ag-Cu series, Sn-Ag series, Sn-Cu series, Sn-Bi series, Sn-Zn series, Sn-In series, etc., which are mainly applied in fields such as electronic packaging and temperature fuses to achieve the connection function between connected materials, such as achieving the connection between electronic components and circuit boards through reflow soldering or wave soldering.

[0005] To ensure the quality of tin-based coatings or tin-based alloy products and reduce the harm caused by corrosion. During actual production, storage, and transportation, surface treatments such as passivation of tin-based coatings or tin-based alloys are usually required. Chinese Patent CN110284131A discloses a passivation process for tinplate with a low tin content, and the passivation solution uses a sodium dichromate solution; Chinese Patent CN114381779A discloses a tinplate with an extremely low tin content having good corrosion resistance and its preparation method, where the tinplate is first phosphated in a phosphate solution and then passivated in a chromate passivation solution. However, such passivation processes using chromate passivation solutions are highly toxic and environmentally polluting. In addition, Chinese Patent CN100564597C, Chinese Patent CN104099649A, Chinese Patent CN105331966A, Chinese Patent CN110938852A, Chinese Patent CN111304706A, Chinese Patent CN110373661A, and Chinese Patent CN104357825A have each disclosed chromium-free passivation processes and treatment methods, but most of these chromium-free passivation processes use phosphorus-containing passivation solutions or various heavy metal salts, which are prone to problems such as eutrophication of water bodies and high waste liquid treatment costs.

[0006] It can be seen that traditional passivation treatment processes more or less use chemical reagents such as chromates, phosphates, heavy metal salts, or concentrated acids. However, with the increasingly strict environmental protection regulations globally, the demand for environmentally friendly processes that are pollution-free, easy to operate, and can improve the corrosion resistance of the surface of tin-based coatings or tin-based alloys is becoming increasingly urgent. Summary of the Invention

[0007] Aiming at the above deficiencies in the prior art, the purpose of the present invention is to provide a surface treatment device and method for improving the corrosion resistance of tin-based coatings or tin-based alloys. The surface treatment device has a simple structure, low cost, and diverse design methods; the surface treatment method is simple, environmentally friendly and pollution-free, with stable treatment effects, strong operability, and is suitable for corrosion resistance treatment of the surfaces of materials such as tin foil, tinplate, pure tin coatings or tin-based binary / multiple coatings, tin-based alloys, and lead-free tin-based solders.

[0008] The technical solution of the present invention is as follows:

[0009] A surface treatment device for improving the corrosion resistance of tin-based coatings or tin-based alloys, including a chamber, a temperature control component, a humidity control component, an ultraviolet generator, and a power supply. The specific structure is as follows:

[0010] The chamber has a processing cavity and a transfer channel. The inner cavity of the chamber is the processing cavity, and the transfer channels are located on both sides of the opposite surfaces of the chamber sidewalls. The transfer channels communicate with the processing cavity. The ultraviolet generator is arranged in the processing cavity and is located above the tin-based coating or tin-based alloy to be processed at the bottom of the processing cavity. The temperature control component is fixed in the processing cavity, communicates and is exposed in the processing cavity through a reserved notch in the chamber. The humidity control component is fixed in the processing cavity, communicates and is exposed in the processing cavity through a reserved notch in the chamber. A reserved notch is provided at the top of the chamber for the wires of the ultraviolet generator to pass through, and the ultraviolet generator is electrically connected to the power supply.

[0011] For the surface treatment device for improving the corrosion resistance of tin-based coatings or tin-based alloys, the temperature control component is used to regulate the environmental temperature in the processing cavity to be consistent with the environmental temperature required by the surface treatment process; the humidity control component is used to regulate the environmental humidity in the processing cavity to be consistent with the environmental humidity required by the surface treatment process; the processing cavity is used to provide the processing environment required by the surface treatment process; the transfer channel is used when the tin-based coating or tin-based alloy sample to be processed is sent into / out of the processing cavity, and the transfer channel is in a closed state during the surface treatment process.

[0012] For the surface treatment device for improving the corrosion resistance of tin-based coatings or tin-based alloys, the ultraviolet generator is exposed in the processing cavity and is in a face-to-face state with the surface of the tin-based coating or tin-based alloy sample to be processed.

[0013] For the surface treatment device for improving the corrosion resistance of tin-based coatings or tin-based alloys, the environmental temperature in the processing cavity is 20 - 50 °C, and the environmental relative humidity (RH) in the processing cavity is 60 - 100% RH.

[0014] For the surface treatment device for improving the corrosion resistance of tin-based coatings or tin-based alloys, preferably, the environmental temperature in the processing cavity is 20 - 30 °C, and the environmental relative humidity (RH) in the processing cavity is 70 - 80% RH.

[0015] For the surface treatment device for improving the corrosion resistance of tin-based coatings or tin-based alloys, the ultraviolet generator is an instrument that emits ultraviolet rays, including but not limited to high-pressure or medium-pressure or low-pressure ultraviolet mercury or mercury lamps, metal halide lamps, light cleaning lamps, plate-making lamps, ultraviolet iron lamps, short-arc xenon lamps or xenon lamps, excimer discharge lamps or ultraviolet aging lamps, with a power range of 8 - 100 W.

[0016] For the surface treatment device for improving the corrosion resistance of tin-based coatings or tin-based alloys, the distance between the ultraviolet generator and the surface of the tin-based coating or tin-based alloy sample to be processed is 0 - 400 mm, corresponding to the irradiation intensity received by the surface of the tin-based coating or tin-based alloy sample to be processed being not less than 0.15 mW / cm 2 。

[0017] The surface treatment device for improving the corrosion resistance of a tin-based coating or tin-based alloy. Preferably, the distance between the ultraviolet generator and the surface of the tin-based coating or tin-based alloy sample to be treated is 100 - 250 mm, corresponding to the irradiation intensity received by the surface of the tin-based coating or tin-based alloy sample to be treated being 5.0 - 0.15 mW / cm 2 .

[0018] A surface treatment method for improving the corrosion resistance of a tin-based coating or tin-based alloy, comprising the following steps:

[0019] (1) Adjust the temperature and relative humidity in the treatment chamber to the temperature range and relative humidity range required by the surface treatment process through the temperature control component and the humidity control component respectively;

[0020] (2) Place the tin-based coating or tin-based alloy sample to be treated into the treatment chamber through the transfer channel, and adjust the distance between the surface of the sample to be treated and the ultraviolet generator to the distance required by the surface treatment process;

[0021] (3) Close the transfer channel;

[0022] (4) Electrically connect the ultraviolet generator to the power supply, and adjust the power of the ultraviolet processor to the ultraviolet power range required by the surface treatment process;

[0023] (5) Mark the start time of the surface treatment process as t0, mark the end time of the surface treatment process as t1, and record the duration of the surface treatment process as t = t1 - t0; According to the required improvement amplitude of the corrosion resistance of the tin-based coating or tin-based alloy sample to be treated, adjust the duration t of the surface treatment process to 10 s to 20 d.

[0024] For the surface treatment method for improving the corrosion resistance of a tin-based coating or tin-based alloy, no other post-treatment process is required on the surface of the tin-based coating or tin-based alloy sample after surface treatment.

[0025] The design concept of the present invention is:

[0026] (1) The present invention utilizes the fact that a protective oxide film layer is easily formed on the surface of a tin-based coating or tin-based alloy. This film layer is relatively dense, has good electrochemical stability, and thus has good corrosion resistance.

[0027] (2) Generally speaking, the outer layer of the protective film layer on the surface of a tin-based coating or tin-based alloy is rich in SnO2, and the inner layer close to the substrate is rich in SnO. SnO2 has better corrosion resistance than SnO. Therefore, the higher the content of SnO2 in the film layer, the better the corrosion resistance of the film layer.

[0028] (3) Both SnO2 and SnO have semiconductor properties and are sensitive to ultraviolet irradiation. Under the action of ultraviolet irradiation, the conversion of SnO to SnO2 will be accelerated, and ultimately more SnO2 will be generated, enhancing the corrosion resistance of the surface oxide film layer;

[0029] (4) When the environmental relative humidity (RH) is 60 - 100% RH, a large amount of SnO exists in the surface oxide film layer of the tin-based coating or tin-based alloy. At this time, under the action of ultraviolet irradiation, a large amount of SnO will be converted into a large amount of SnO2, increasing the content of SnO2 in the film layer and improving the compactness of the film layer. Therefore, the corrosion resistance of the film layer on the surface of the tin-based coating or tin-based alloy is improved.

[0030] Compared with the prior art, the advantages and beneficial effects of the present invention are:

[0031] (1) The environmental temperature in the treatment chamber of the present invention is 20 - 50 °C, and the relative humidity (RH) is 60 - 100% RH. This environment easily enables a thin water film to form on the surface of the tin-based coating or tin-based alloy, accelerating the corrosion of the tin-based coating or tin-based alloy substrate and generating a large amount of SnO products, providing an accumulation of product quantity for the subsequent conversion of SnO to SnO2.

[0032] (2) The source of ultraviolet rays in the present invention is abundant. The ultraviolet generator includes but is not limited to ultraviolet mercury (mercury) lamps (high pressure / medium pressure / low pressure), metal halide lamps, photo cleaning lamps, printing platesetting lamps, ultraviolet iron lamps, short arc xenon lamps (xenon lamps), excimer discharge lamps, and ultraviolet aging lamps.

[0033] (3) The ultraviolet rays in the present invention can accelerate the conversion of SnO to SnO2, increasing the content of SnO2 in the surface film layer of the tin-based coating or tin-based alloy and improving the compactness of the film layer. Therefore, the corrosion resistance of the film layer on the surface of the tin-based coating or tin-based alloy is improved.

[0034] (4) The surface treatment method for improving the corrosion resistance of the tin-based coating or tin-based alloy provided by the present invention does not use chemical reagents such as chromates, phosphates, heavy metal salts, or concentrated acids. The process is simple, environmentally friendly and pollution-free, the treatment effect is stable, and the device structure is simple, the design method is diverse, and the operability is strong, which can accelerate the formation of the protective film layer on the surface of the tin-based coating or tin-based alloy. Description of the Drawings

[0035] Figure 1 Schematic diagram of the surface treatment device for improving the corrosion resistance of the tin-based coating or tin-based alloy according to an embodiment of the present invention;

[0036] Figure 2 Comparison diagram of the impedance modulus values of lead-free pure tin solder exposed to dark atmosphere and ultraviolet irradiated atmosphere for 20 d in the embodiment. In the figure, the ordinate impedance modulus value represents the corrosion resistance (kΩ·cm2 ), the larger the impedance modulus, the better the corrosion resistance.

[0037] Explanation of reference numerals:

[0038] 10. Surface treatment device for improving the corrosion resistance of tin-based coatings or tin-based alloys; 100. Chamber; 110. Processing chamber; 120. Conveyor channel; 200. Temperature control component; 300. Humidity control component; 400. Ultraviolet generator; 500. Tin-based coating or tin-based alloy to be processed; 600. Power supply. Detailed implementation manners

[0039] To facilitate the understanding of the present invention, the present invention will be described more comprehensively below with reference to the relevant drawings. Preferred embodiments of the present invention are shown in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0040] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there can also be a middle element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be a middle element at the same time.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs. The terms used in the description of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0042] See Figure 1 As shown, this embodiment relates to a surface treatment device 10 for improving the corrosion resistance of tin-based coatings or tin-based alloys. The surface treatment device 10 for improving the corrosion resistance of tin-based coatings or tin-based alloys includes a chamber 100, a temperature control component 200, a humidity control component 300, an ultraviolet generator 400, a tin-based coating or tin-based alloy 500 to be processed, and a power supply 600.

[0043] The chamber 100 has a processing chamber 110 and a transfer channel 120. The inner cavity of the chamber 100 is the processing chamber 110. The transfer channel 120 is located on both sides of the opposite surfaces of the side walls of the chamber 100, and the transfer channel 120 communicates with the processing chamber 110; the ultraviolet generator 400 is disposed in the processing chamber 110; the temperature control component 200 is fixed to the processing chamber 110, communicates and is exposed in the processing chamber 110 through a reserved notch of the chamber 100, and is located above the tin-based coating or tin-based alloy 500 to be processed at the bottom of the processing chamber 110; the humidity control component 300 is fixed to the processing chamber 110, communicates and is exposed in the processing chamber 110 through a reserved notch of the chamber 100; a reserved notch is provided at the top of the chamber 100 for the wire of the ultraviolet generator 400 to pass through, and the ultraviolet generator 400 is electrically connected to the power supply 600.

[0044] See Figure 1 As shown, the temperature control component 200 is used to regulate the environmental temperature in the processing chamber 110 to be consistent with the environmental temperature required by the surface treatment process. Its specification model can be the Deli DL336101 temperature controller; the humidity control component 300 is used to regulate the environmental humidity in the processing chamber 110 to be consistent with the environmental humidity required by the surface treatment process. Its specification model can be the Acrel WHD46-22 humidity controller; the processing chamber 110 is used to provide a processing environment required by the surface treatment process; the transfer channel 120 is used when the tin-based coating or tin-based alloy sample 500 to be processed is sent into / out of the processing chamber 110, and the transfer channel 120 is in a closed state during the surface treatment process.

[0045] See Figure 1 As shown, the ultraviolet generator 400 is exposed in the processing chamber 110 and is in a face-to-face state with the surface of the tin-based coating or tin-based alloy sample 500 to be processed. Its specification model can be the Guanhongya UVA-340 ultraviolet aging lamp.

[0046] See Figure 1 As shown, the environmental temperature in the processing chamber 110 is 20 to 50 °C, but the processing effect is best when the environmental temperature is 20 to 30 °C.

[0047] See Figure 1 As shown, the environmental relative humidity (RH) in the processing chamber 110 is 60 to 100%RH, but the processing effect is best when the environmental relative humidity is 70 to 80%RH.

[0048] See Figure 1 As shown, the ultraviolet generator 400 is an appliance that can emit ultraviolet rays, including but not limited to ultraviolet mercury (mercury) lamps (high pressure / medium pressure / low pressure), metal halide lamps, light cleaning lamps, plate-making lamps, ultraviolet iron lamps, short-arc xenon lamps (xenon lamps), excimer discharge lamps or ultraviolet aging lamps, and the power range is 8 to 100W.

[0049] See Figure 1 As shown, the distance between the ultraviolet generator 400 and the surface of the tin-based coating or tin-based alloy sample 500 to be treated is 0 to 400 mm, but the treatment effect is best when the distance is 100 to 250 mm, corresponding to the irradiation intensity received by the surface of the tin-based coating or tin-based alloy sample 500 to be treated is not less than 0.15 mW / cm 2 .

[0050] When the surface treatment device for improving the corrosion resistance of tin-based coatings or tin-based alloys is used for surface treatment to improve the corrosion resistance of tin-based coatings or tin-based alloys, a surface treatment method for improving the corrosion resistance of tin-based coatings or tin-based alloys is involved.

[0051] A surface treatment method for improving the corrosion resistance of tin-based coatings or tin-based alloys includes the following steps:

[0052] See Figure 1 As shown, the temperature in the treatment chamber 110 is adjusted to 25°C and the relative humidity is adjusted to 80% RH through the temperature control component 200 and the humidity control component 300 respectively;

[0053] See Figure 1 As shown, the tin-based coating or tin-based alloy sample 500 to be treated is placed into the treatment chamber 110 through the transfer channel 120, and the distance between the surface 500 of the sample to be treated and the ultraviolet generator 400 is adjusted to 100 mm, corresponding to the irradiation intensity received by the surface of the tin-based coating or tin-based alloy sample 500 to be treated is 5.0 to 0.35 mW / cm 2 ;

[0054] See Figure 1 As shown, the transfer channel 120 is closed;

[0055] See Figure 1 As shown, the ultraviolet generator 400 is electrically connected to the power supply 600, and the power of the ultraviolet processor 400 is adjusted to the ultraviolet power range required by the surface treatment process, such as: using an ultraviolet aging lamp with a power of 8 to 100 W;

[0056] See Figure 1 As shown, the start time of the surface treatment process is marked as t0, the end time of the surface treatment process is marked as t1, and the time maintained by the surface treatment process is recorded as t = t1 - t0. According to the requirement for the improvement amplitude of the corrosion resistance of the tin-based coating or tin-based alloy sample 500 to be treated, the time t maintained by the surface treatment process is adjusted to 20 d (days).

[0057] See Figure 1As shown, no other post-treatment processes are required for the surface of the tin-based coating or tin-based alloy sample 500 after surface treatment.

[0058] As Figure 2 shown, the experimental data after treating with the surface treatment method for improving the corrosion resistance of tin-based coatings or tin-based alloys in this embodiment are as follows: The surface of lead-free pure tin solder is treated by ultraviolet irradiation. After 10 days (d), the impedance modulus values of the lead-free pure tin solder treated and untreated by the case (embodiment) are 1800 kΩ·cm 2 and 900 kΩ·cm 2 . It can be seen that the corrosion resistance of the pure Sn solder after ultraviolet treatment is twice that of the pure Sn solder sample without ultraviolet treatment.

[0059] The results of this embodiment show that the surface treatment method of the present invention for improving the corrosion resistance of tin-based coatings or tin-based alloys can effectively improve the corrosion resistance of the surface of lead-free pure tin solder, with simple process, environmental protection and no pollution, stable treatment effect and strong operability.

[0060] In addition, in the embodiment, the corrosion resistance treatment is carried out on the surfaces of materials such as tin foil, tinplate, pure tin coating or tin-based binary / multicomponent coatings (such as: pure Sn coating, Sn-Zn coating, Sn-Cu coating), tin-based alloys (such as tin-based bearing alloy: ZchSnSb11-6, ZchSnSb8-4), and lead-free tin-based solder alloys (such as: Sn-Ag series, Sn-Cu series and Sn-Ag-Cu series). After ultraviolet treatment, the corrosion resistance of the tin foil is twice that of the tin foil sample without ultraviolet treatment; the corrosion resistance of the tinplate is twice that of the tinplate sample without ultraviolet treatment; the corrosion resistance of the pure tin coating is 2.8 times that of the pure tin coating sample without ultraviolet treatment; the corrosion resistance of the tin-based binary / multicomponent coating is 3 times that of the tin-based binary / multicomponent coating sample without ultraviolet treatment; the corrosion resistance of the tin-based alloy is 3 times that of the tin-based alloy sample without ultraviolet treatment. It can be seen that the results of the embodiment show that the surface treatment method of the present invention for improving the corrosion resistance of tin-based coatings or tin-based alloys can effectively improve the corrosion resistance of the surface of tin-based coatings or tin-based alloys, with simple process, environmental protection and no pollution, stable treatment effect and strong operability.

[0061] The results show that the present invention combines a temperature control component, a humidity control component, an ultraviolet generator, etc. and they act synergistically, where: the temperature control component is used to adjust the temperature in the processing chamber; the humidity control component is used to adjust the humidity in the processing chamber; the ultraviolet generator is used to emit ultraviolet rays required for the surface treatment process and is connected to a power source. The tin-based coating or tin-based alloy sample to be processed is exposed in the processing chamber and is in a "face-to-face" state with the ultraviolet generator; the ultraviolet generator is turned on to perform ultraviolet irradiation treatment on the tin-based coating or tin-based alloy sample. Thus, a surface treatment for improving the corrosion resistance of the tin-based coating or tin-based alloy can be carried out, and the treatment effect is stable.

[0062] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0063] The above-described embodiments only represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

1. A surface treatment method for improving the corrosion resistance of a tin-based coating or tin-based alloy, characterized in that, The method adopts a surface treatment device for improving the corrosion resistance of a tin-based coating or a tin-based alloy, which includes a chamber, a temperature control component, a humidity control component, an ultraviolet generator, and a power supply. The specific structure is as follows: The chamber has a treatment cavity and a transfer channel. The inner cavity of the chamber is the treatment cavity, and the transfer channels are located on both sides of the opposite surfaces of the chamber sidewall. The transfer channels communicate with the treatment cavity. The ultraviolet generator is arranged in the treatment cavity and is located above the tin-based coating or tin-based alloy to be treated at the bottom of the treatment cavity. The temperature control component is fixed in the treatment cavity and communicates and is exposed in the treatment cavity through a reserved notch in the chamber. The humidity control component is fixed in the treatment cavity and communicates and is exposed in the treatment cavity through a reserved notch in the chamber. A reserved notch is provided at the top of the chamber for the wire of the ultraviolet generator to pass through, and the ultraviolet generator is electrically connected to the power supply; The temperature control component is used to adjust the environmental temperature in the treatment cavity to be consistent with the environmental temperature required by the surface treatment process; the humidity control component is used to adjust the environmental humidity in the treatment cavity to be consistent with the environmental humidity required by the surface treatment process; the treatment cavity is used to provide a treatment environment required by the surface treatment process; the transfer channel is used when the tin-based coating or tin-based alloy sample to be treated is sent into / removed from the treatment cavity, and the transfer channel is in a closed state during the surface treatment process; The ultraviolet generator is exposed in the treatment cavity and is in a face-to-face state with the surface of the tin-based coating or tin-based alloy sample to be treated; The environmental temperature in the treatment cavity is 20 - 30 °C, and the environmental relative humidity (RH) in the treatment cavity is 70 - 80%RH; The distance between the ultraviolet generator and the surface of the tin-based coating or tin-based alloy sample to be treated is 0 to 400 mm, corresponding to the irradiation intensity received by the surface of the tin-based coating or tin-based alloy sample to be treated being not less than 0.15 mW / cm 2 ; The method includes the following steps: (1) Adjust the temperature and relative humidity in the treatment cavity to the temperature range and relative humidity range required by the surface treatment process respectively through the temperature control component and the humidity control component; (2) Place the tin-based coating or tin-based alloy sample to be treated into the treatment cavity through the transfer channel, and adjust the distance between the surface of the sample to be treated and the ultraviolet generator to the distance required by the surface treatment process; (3) Close the transfer channel; (4) Electrically connect the ultraviolet generator to the power supply, and adjust the power of the ultraviolet processor to the ultraviolet power range required by the surface treatment process; (5) Mark the start time of the surface treatment process as t0, mark the end time of the surface treatment process as t1, and record the time maintained by the surface treatment process as t = t1 - t0; according to the requirement for the improvement amplitude of the corrosion resistance of the tin-based coating or tin-based alloy sample to be treated, adjust the time t maintained by the surface treatment process to be 10 s to 20 d.

2. The surface treatment method for improving the corrosion resistance of a tin-based coating or tin-based alloy according to claim 1, characterized in that, The ultraviolet generator is an instrument that emits ultraviolet rays, including high-pressure or medium-pressure or low-pressure ultraviolet mercury lamps, metal halide lamps, ultraviolet iron lamps or excimer discharge lamps, and the power range is 8 - 100 W.

3. The surface treatment method for improving the corrosion resistance of a tin-based coating or tin-based alloy according to claim 1, characterized in that, The distance between the ultraviolet generator and the surface of the tin-based coating or tin-based alloy sample to be treated is 100 to 250 mm, corresponding to an irradiation intensity received by the surface of the tin-based coating or tin-based alloy sample to be treated of 5.0 to 0.15 mW / cm 2 .

4. The surface treatment method for improving the corrosion resistance of a tin-based coating or tin-based alloy according to claim 1, wherein, For the surface of the tin-based coating or tin-based alloy sample after surface treatment, no other post-treatment processes are required.

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