A flux for solder wire used in soft soldering of nickel parts and its preparation method

Abstract

A flux for soldering nickel components and its preparation method are disclosed. The flux comprises the following raw materials: 2.0-8.0% compounded dicarboxylic acid, 1.0-10.0% compounded ionic halogenated activator, 1.0-5.0% compounded covalent halogenated activator, 0.3-3.0% compounded surfactant, 0.5-3.0% metal salt, 0.1-1.0% antioxidant, 1.0-5.0% organic alcohol amine, 0.01-1.0% masking agent, 2.0-6.0% organic solvent, and the balance being compounded modified rosin resin. The flux for soldering nickel components of this invention exhibits high activity, fast tinning rate, easy wetting, bright, full, and clean solder joints, high residual dryness, excellent spatter control, and a comfortable and pleasant soldering experience during the soldering process. It can be industrialized with high quality and stability. The flux preparation method of the present invention is precise and standardized, which can protect the active functional groups of each additive from damage or minimize the degree of damage during the high-temperature preparation process, thereby achieving high quality and excellent stability of flux preparation.

Description

Technical Field

[0001] This invention belongs to the field of electronic soldering materials technology, specifically relating to solder wire flux for soldering nickel parts and its preparation method. Background Technology

[0002] In recent years, the market demand for nickel-plated electronic components or nickel-based materials using solder wire has been increasingly strong. Nickel possesses excellent conductivity, corrosion resistance, wear resistance, and heat resistance, which can extend the lifespan of electronic components. For example, nickel plating is often used in switch contacts and plug-in components to improve their wear and corrosion resistance. Nickel can also be used as a component of the base material to improve the stability and reliability of devices. Therefore, nickel is widely used in the electronics and electrical appliance fields, and the nickel metal materials used in these fields mainly include pure nickel metal, nickel alloys, and nickel-plated copper.

[0003] While conventional solder wires on the market offer excellent tinning performance for tin-plated and copper parts, they either fail to tinnize nickel parts at all or exhibit poor tinning performance, resulting in various soldering failures such as incomplete solder joints, easy detachment, delusion, and spiking of old solder, making it difficult to achieve ideal soldering requirements. The key reasons for this are twofold: First, from the perspective of the base material, the oxide layer on the surface of nickel parts is more difficult to remove quickly than that on tin-plated and copper parts. Based on soldering experience, the difficulty of removing the oxide layer from the base metal surface of the same type of L1 active solder wire is ranked as follows: nickel parts > copper parts > tin-plated parts. Second, from the perspective of the solder wire itself, the flux activity in the core of these solder wires is insufficient, or the activator design in the flux formula is flawed. The solder wire lacks sufficient activity to quickly remove the oxide layer from the surface of the nickel base metal, leading to soldering failures. Therefore, to achieve high-quality soft soldering of nickel parts with solder wire, the material properties of the nickel parts themselves cannot be changed. The only solution is to modify the flux properties of the solder wire core to quickly remove the dense oxide layer passivated on the surface of the nickel base metal and achieve the ideal soldering quality.

[0004] Research on flux for solder wire used in nickel soldering has been a persistent pursuit by Chinese researchers. In 2003, Chinese invention patent publication CN1449886A disclosed a flux for stainless steel that could also be used for soldering nickel-plated surfaces. It used a system of 20%-30% phosphoric acid, 10%-15% zinc chloride, and 10%-15% ammonium chloride as activators, with 40%-60% water as the carrier. This type of flux has very serious residual corrosion after soldering. In addition, even if the flux can be packaged into the core of the solder wire, it cannot solidify and be further refined. Therefore, it is not suitable for preparing solder wire with a solid flux core. In 2008, Chinese invention patent publication number CN101204762A disclosed a lead-free flux for soft soldering of aluminum and aluminum alloys, which can also be used for lead-free soft soldering of metal materials such as nickel alloys. It uses a system of 5-50% metal salts that can be reduced by aluminum, 10-50% film remover, 3-40% wetting agent, 3-20% activator, and 1-15% surfactant as activator, and also contains 2-20% corrosion inhibitor and the balance carrier. This flux is too corrosive and is paste-like rather than solid at room temperature, so it is not suitable for the production of solder wire with a solid flux core. In 2012, Chinese invention patent publication CN102728967A disclosed a flux for solder wire cores used in soft soldering of nickel-plated alloys. The flux uses an activator system consisting of 0.1%-20% organic acid, 0.1%-10% organic amine, 0.1%-20% metal salt, and 0.1%-2.0% activity enhancer, and other additives consisting of 0.1%-2.0% surfactant, 0.1%-1.0% corrosion inhibitor, and 0.1%-1.0% antioxidant. While this technology can achieve excellent soft soldering of nickel-plated alloys, its performance on pure nickel or nickel alloy substrates remains unclear. Furthermore, the formulation contains a significant amount of high-melting-point reagents such as cyclohexylamine hydrobromide and hexadecyltrimethylammonium bromide, which, based on experience, are difficult to fully melt or dissolve evenly in a 140±5℃ temperature bath. Additionally, the addition of a large amount of activator and additive components results in irritating fumes and odors during soldering, raising concerns about the adaptability of on-site soldering workers.In 2018, Chinese invention patent publication number CN109014662A disclosed a flux for soft soldering of multi-metal materials. The solder wire made from this flux can be used for soldering of various metal materials such as nickel and nickel alloys, stainless steel, aluminum and aluminum alloys. The formulation consists of 20-80% alkyd ionic liquid, 5-20% zinc fluoroborate, 5-30% zinc oxide, 2-20% basic zinc carbonate, 0.1-2% surfactant, and 0.05-0.1% corrosion inhibitor. During the preparation process, the temperature in step S2 is 95-105℃, and the temperature in step S3 is below 40℃. This flux formulation is almost entirely composed of activators. Although it has excellent soldering activity for nickel parts, there are significant risks of severe corrosion and insufficient drying after soldering. Furthermore, the low temperature during the preparation process poses a significant challenge to the rapid solidification and subsequent production line diameter-changing deep processing after being filled into the solder rod core.

[0005] In summary, the research and development of flux for nickel soldering has progressed from liquid to paste to solid states, culminating in a solid flux that can be solidified for use with solder wire cores. From a formulation perspective, it has evolved from relatively simple to more comprehensive formulation systems. Regarding core technologies, the focus has shifted towards superior activity performance, moving from relatively simple activator systems primarily based on metal salts to more complex systems incorporating metal salts, organic acids, organic amines, and activity enhancers, with some formulations even consisting almost entirely of activators. Finally, in terms of application performance, fluxes demonstrate increasingly superior overall reliability in terms of tinning activity, wetting, and corrosion inhibition for nickel soldering. However, although significant progress has been made in the research of flux for solder wire used in nickel soldering, there is still much room for improvement. Firstly, while the overall structure of the formulation is becoming more comprehensive, it lacks a more refined and industrially viable design concept. Secondly, most fluxes are not purely solid at room temperature, which will cause them to fail the flux residue dryness test. Thirdly, the core technology in flux formulations—the activator system—lacks sufficient refinement in its design. Fourthly, whether the flux preparation methods can guarantee stable and controllable solder wire quality during actual industrial production lines is a key consideration. Fifthly, flux research has almost entirely focused on welding activity and reliability, neglecting the user experience of solder wire application. For example, formulas containing large amounts of activators and additives may produce excessive fumes, irritating odors, and potentially severe solder splattering, without considering whether on-site employees can adapt to and accept these issues during soldering operations. Summary of the Invention

[0006] This invention, taking into account the practicalities of industrialized production lines for solder wire flux used in nickel soldering, the demand for excellent solderability and reliability of nickel parts, and the humanized needs of market customers for a pleasant and comfortable on-site soldering experience, aims to overcome the shortcomings of existing technologies by providing an environmentally friendly solder wire flux for nickel soldering that features high activity, fast tinning rate, easy wetting, bright, full, and clean solder joints, high residual dryness, excellent spatter control, a comfortable and pleasant soldering experience, and the ability to be industrialized with high quality and stability. This invention also provides a method for preparing this flux.

[0007] The technical solution adopted in this invention is as follows:

[0008] A flux for soldering nickel parts, by weight percentage, comprises the following raw materials:

[0009] Compound binary organic carboxylic acids 2.0-8.0%,

[0010] Compound ionic halogenated activators 1.0-10.0%,

[0011] Compound covalent halogenated activators 1.0-5.0%,

[0012] Compound surfactant 0.3-3.0%,

[0013] Metal salts 0.5-3.0%,

[0014] Antioxidant 0.1-1.0%,

[0015] Organic alcohol amines 1.0-5.0%,

[0016] Odor masking agent 0.01-1.0%,

[0017] Organic solvents 2.0-6.0%,

[0018] The remainder of the compounded modified rosin resin;

[0019] The compounded dicarboxylic acid is a combination of two or more of the following: methyl succinic acid, succinic anhydride, glutaric acid, glutaric anhydride, adipic acid, octanoic acid, sebacic acid, dodecanoic acid, and tridecanoic acid.

[0020] The compound ionic halogenated activator is a combination of two or more of the following: cyclohexylamine hydrobromide, diethylamine hydrobromide, p-tert-butylimidazolium hydrobromide, diphenylguanidine hydrobromide, 2-bromoethylamine hydrobromide, isopropylamine hydrobromide, 2-ethylimidazolium hydrobromide, n-butylmonophenylamine hydrobromide, cyclohexylamine hydrochloride, dimethylamine hydrochloride, ethylenediamine hydrochloride, triethanolamine hydrochloride, and diphenylguanidine hydrochloride.

[0021] The compounded covalent halogenated activator is chlorobrines, dibromobutenediol, dibromoethylbenzene, hydrazine bromide, and dibromosuccinic acid. Combinations of two or more of 2-chlorosuccinic acid;

[0022] The compound surfactant is a combination of a nonionic surfactant and an ionic surfactant, or a combination of a nonionic fluorocarbon surfactant and an ionic surfactant.

[0023] The metal salt is one or a combination of two or more of stannous chloride, stannous oxalate, and stannous methanesulfonate.

[0024] The antioxidant is one or a combination of two or more of BASF Ciba antioxidants 1010, 168, 1076, 1098, B215, and antioxidant BHT.

[0025] The organic alcohol amine is one or a combination of two or more of monoethanolamine, diethanolamine, triethanolamine, triisopropanolamine, and diethanol monoisopropanolamine;

[0026] The masking agent is one or a combination of two or more of the following: fruity masking agents, floral masking agents, aromatic masking agents, herbal masking agents, and fantasy masking agents.

[0027] The organic solvent is one or a combination of two or more of the following: methanol, tetrahydrofurfuryl alcohol, ethylene glycol monomethyl ether, propylene glycol monomethyl ether, propylene glycol ethyl ether, propylene glycol propyl ether, propylene glycol butyl ether, diethylene glycol methyl ether, tripropylene glycol methyl ether, tripropylene glycol butyl ether, dipropylene glycol butyl ether, and N-methylpyrrolidone.

[0028] The modified rosin resin is a combination of two or more of the following: hydrogenated water white rosin, refined hydrogenated rosin, Eastman fully hydrogenated rosin AX-E, fully hydrogenated rosin AX-80, acrylic acid modified hydrogenated rosin HM-604, and 3250 rosin.

[0029] Furthermore, the nonionic surfactant is one of oleyl alcohol polyoxyethylene ether, TX-10 phosphate ester, octylphenol polyoxyethylene ether, NP-10, and OP-10; the nonionic fluorocarbon surfactant is FS-3000 or FS-3100; and the ionic surfactant is one of hexadecyltrimethylammonium chloride, octadecyltrimethylammonium chloride, hexadecyltrimethylammonium bromide, and octadecyltrimethylammonium bromide.

[0030] Furthermore, the fruity masking agent is one of 851, 855, 856, 858, and 859; the floral masking agent is one of rose essence, jasmine essence, osmanthus essence, lily of the valley essence, magnolia essence, gardenia essence, lavender essence, violet essence, tuberose essence, acacia essence, and chrysanthemum essence; the aromatic masking agent is one of lemon aromatic essence, peppermint aromatic essence, sandalwood aromatic essence, tea tree aromatic essence, orange blossom aromatic essence, and lily aromatic essence; the herbaceous masking agent is one of artemisia essence, rosemary essence, lemongrass essence, eucalyptus essence, sage essence, thyme essence, lemongrass essence, and basil essence; and the fantasy masking agent is one of dream mist essence, fantasy rainbow essence, starry sky essence, magical forest essence, and dream island essence.

[0031] The preparation method of the flux for solder wire used in soft soldering of nickel parts according to the present invention comprises the following steps:

[0032] (1) After mixing solid dicarboxylic acid, a portion of covalent halogenated activator, a portion of ionic halogenated activator, metal salt, and antioxidant, the mixture is sealed in a solid reagent bottle for later use to obtain compound solid additive A;

[0033] (2) A portion of organic solvent is loaded into the reaction vessel, and then a portion of solid covalent halogenated activator, a portion of solid ionic halogenated activator, a portion of liquid covalent halogenated activator, a portion of ionic halogenated activator, and a compound surfactant are added to the reaction vessel. The mixture is stirred thoroughly at room temperature to ensure that all materials are fully dissolved and mixed evenly. The mixture is filtered through a filter screen to obtain a mixed solution. The mixed solution is then sealed in a liquid reagent bottle for later use to obtain a compound mixed solution B.

[0034] (3) Put the remaining organic solvent into the reaction vessel, and then put the organic alcohol amine, masking agent, remaining liquid covalent halogenated activator, and remaining liquid ionic halogenated activator into the reaction vessel. Stir, dissolve, mix and dilute at room temperature to obtain a fully dissolved and homogeneous diluted solution. Seal the diluted solution in a liquid reagent bottle for later use to obtain the compound diluted solution C.

[0035] (4) Add the compounded modified rosin resin into the flux production reactor and heat and stir at a constant temperature until completely melted;

[0036] (5) The compound solid additive A prepared in step (1) is slowly added to the molten compound modified rosin resin in step (4) while stirring. The mixture is continuously heated and stirred at a constant temperature so that the compound solid additive A is quickly dispersed into the molten rosin to obtain compound material D.

[0037] (6) While stirring, slowly add the compound mixture solution B prepared in step (2) to the compound material D in step (5), continue heating and stirring at a constant temperature, so that the compound solid additive A and the compound mixture solution B are completely melted and dissolved in the molten rosin to obtain compound material E;

[0038] (7) While stirring, slowly add the compound dilution solution C prepared in step (3) to the compound material E in step (6), continue heating and stirring at a constant temperature until the compound dilution solution C and the compound material E react fully and are dissolved and mixed evenly to obtain compound material F;

[0039] (8) Stop heating and stirring, and let the compound material F prepared in step (7) stand for 5 to 10 minutes under its own residual heat, so that the water phase and oil phase components in the compound material F can be separated by gravity. The water phase precipitate at the bottom is directly removed, and the upper oil phase is retained to obtain the flux for soldering nickel parts.

[0040] Furthermore, the flux for soldering nickel parts prepared above is packaged into the inner core of a leaded or lead-free solder rod using an extrusion press to process and prepare the solder wire product.

[0041] Further, the heating temperature of the compound modified rosin resin in step (4) is 150±10℃; the heating temperature of the compound material D in step (5) is 150±10℃; the heating temperature of the compound material E in step (6) is 150±10℃; and the heating temperature of the compound material F in step (7) is 145±5℃.

[0042] This invention proposes a flux for solder wire soldering of nickel parts, specifically designed for soldering nickel substrates with solder wire. By optimizing the activator structure and characteristics in the flux formulation and the preparation method for industrial-scale production of the flux, the flux activity and industrial-scale application experience required for soldering nickel parts are enhanced.

[0043] The flux for soldering nickel components according to the present invention has the following advantages:

[0044] (1) The flux for soldering nickel parts in this invention has excellent tinning and solderability for nickel parts. This invention has been demonstrated through practical experience and adopts a comprehensive and refined activator system. First, a reducing tin metal salt is used to react with the oxide layer of the nickel part to cause local cracking of the dense oxide layer with a "shell" structure on the surface of the nickel part. Then, an alcohol amine further reacts with the oxide layer of the nickel part to a certain strength, consuming the oxide layer of the nickel part and aggravating the width of the local cracks. Then, halides and organic acids penetrate the thin oxide layer of the nickel part and along the cracks in the locally cracked oxide layer, continuously reacting with nickel oxide until it is completely consumed. The activator continuously activates the surface of the molten nickel part, keeping it a clean pure metal bath. The solder also forms a clean pure tin solder metal bath under the same action principle of the activator. After contact, the two diffuse with each other to form an IMC layer with a certain uniform thickness, which enhances the mechanical properties of the solder joint and completes the soldering. The amount of tin metal salt should not be too large, otherwise it will precipitate during the flux production process due to its reducing properties, affecting the quality and stability of the flux.

[0045] (2) The flux for soldering nickel parts in this invention is guided by the actual application needs of the market. It comprehensively considers industrial production, the actual application technology needs of market customers, product quality stability and performance reliability, etc., and rationally designs and improves the flux formulation structure. It also adopts the compound design concept to make the actual application performance of the formulation more perfect. First, by using compound rosin as the carrier system, the advantages of different rosins can be brought into play, their defects can be reduced to a certain extent, the advantages and disadvantages can be complemented, and the stability of the overall performance of the flux can be improved. Secondly, a complex activator system consisting of compounded dicarboxylic acids, compounded ionic halogenated activators, compounded covalent halogenated activators, metal salts, and organic alcohol amines is employed to achieve excellent tinning and solderability for nickel parts. On one hand, the overall activator system comprises multiple different types of activators, ensuring the flux formulation possesses sufficient strong activity to achieve excellent soft soldering characteristics for nickel parts. Furthermore, each type of activator has different soldering activation characteristics, thus ensuring excellent soft soldering characteristics for tin-plated parts, copper parts, and other materials. On the other hand, activators of the same type are also generally designed in a compound manner to achieve complementary advantages and disadvantages between different activators, maximizing or even improving activation performance. In addition, the compound design effectively reduces the proportion of a single activator in the formulation, improving the stability of the overall flux performance. This ensures that the activity of the formulation is not reduced, while avoiding the abnormal situation of precipitation, sedimentation, or stratification caused by excessively increasing the proportion of a single activator in the formulation to increase activity intensity. Next, a combination of nonionic and ionic surfactants is used to help remove minute contaminants and oxides from the surface of the solder joints, creating conditions for a good bond between the solder and the joints. During the soldering process, these surfactants effectively reduce the surface tension of the flux and liquid solder, allowing the solder to spread better on the solid surface of the joints. This promotes better penetration of the activator into the oxide layer on the joint surface, enhancing the removal effect of the activator and improving soldering quality and reliability. Furthermore, the nonionic surfactants have good compatibility with other components in the flux, ensuring uniform dispersion of the flux components and improving flux stability. Post-soldering residues are less likely to cause short circuits or other adverse effects on electronic components. The addition of a small amount of ionic surfactant, which contains halide ions, acts as an activator. Finally, antioxidants can prevent or delay the oxidation reaction of the metal during soldering and the rapid deactivation of the flux due to oxidation in high-temperature environments, improving soldering quality and reliability. Finally, the masking agent can effectively mask other irritating odors. The organic solvent can not only effectively dissolve various solid active ingredients in the flux during the flux preparation process, promoting the rapid dissolution and melting of each component in the molten rosin, but some solvents will also evaporate and escape, improving the quality stability and morphological stability of the flux. Furthermore, it can improve the fluidity of the flux during the soldering process, creating favorable conditions for solder adhesion.

[0046] (3) The method for preparing flux for solder wire in nickel soldering of the present invention mainly consists of four parts: preparation and packaging of solid additives, preparation and packaging of mixed solution additives, preparation and packaging of diluted solution additives, and production and preparation of flux. The production and preparation of flux consists of five steps: smelting of rosin, feeding of solid additives, feeding of mixed solution additives, feeding of diluted solution additives, and static gravity sedimentation oil-water phase separation. The method for preparing flux for solder wire of the present invention fully refines and standardizes the operation process and even the steps, and has very precise and practical operability. Each additive in the formula is finely classified, weighed and packaged according to its physicochemical properties, and the flux is prepared by scientific feeding, so as to protect the active functional groups of each additive from damage or minimize the degree of damage during the high-temperature preparation process, thereby achieving high quality and excellent stability of flux preparation. In addition, the flux preparation temperature is basically constant at about 150°C, which is very convenient for production operation control. The solder wire flux preparation method of the present invention has been verified and continuously improved by the author's research team over many years of practice. It can not only be prepared in the laboratory at an experimental level, but also directly put into production line for assembly line production.

[0047] (4) The flux for soldering nickel parts in this invention, due to the rational design of its flux formula structure and the refined flux preparation and production operation method, has excellent comprehensive performance. It has high activity during the welding process, fast tinning rate, and easy wetting. It not only has excellent tinning and wetting solderability for nickel parts, but also has excellent soft soldering characteristics for tin-plated parts, copper parts and other materials. At the same time, it has low corrosion, excellent spatter performance, good electrical performance, and the solder joints after welding are bright, full and clean. The chalk powder on the surface of the solder pool is easy to remove, the residual dryness is high, the flux quality is stable, and it can be put into industrial production. In particular, the flux formulation of this invention uses organic alcohol amines, which have two active functional groups, hydroxyl and amino, and function as activators to improve the flux's removal effect on metal surface oxides. They are weakly alkaline and function as corrosion inhibitors, neutralizing some of the acidic components in the flux, thereby adjusting the flux's pH to maintain it within a suitable range. This ensures good deoxidation ability without causing excessive corrosion to the welded parts due to excessive acidity. Furthermore, practical experience has shown that they also act as brighteners, making solder joints brighter, cleaner, and more aesthetically pleasing.

[0048] (5) The flux for soldering nickel parts in this invention incorporates an odor masking agent in its formulation, effectively masking the irritating odor generated during the soldering process, making it more pleasant, and allowing for humanized adjustments based on the actual application experience of customers. Because the flux formulation contains a large amount of rosin and a certain amount of organic acids, halides, antioxidants, and other additives, some of these chemical substances will volatilize or decompose during the high-temperature soldering process, producing many irritating chemical odors. Such irritating chemical odors are unavoidable in any solder wire flux during the soldering process, and the more activators and other chemical additives are added, the stronger the irritating chemical odors become, causing on-site employees of application manufacturers to be unable to adapt during the soldering operation, and even develop strong rejection and resistance, making it impossible to effectively promote and apply the solder wire products. Practical experience has shown that adding a pleasant-smelling masking agent to the flux can effectively mask the irritating chemical odors produced during the soldering process, making them more pleasant and enhancing the user experience and acceptance of solder wire. This leads to smoother application and more efficient promotion of solder wire products in the market.

[0049] (6) The flux for solder wire for nickel soldering of the present invention meets the environmental protection requirements of EU RoHS 3.0 and REACH. It is applicable not only to lead-free solder soldering but also to lead solder soldering, and can be used to prepare solder wire products with various specifications of solder cores and wire diameters. Detailed Implementation

[0050] The present invention will be further described in detail below through embodiments, but the scope of protection of the present invention is not limited to the contents described in the embodiments.

[0051] Example 1

[0052] A flux for soldering nickel components, comprising the following raw materials by weight percentage:

[0053] Refined hydrogenated rosin 67.27%

[0054] Eastman fully hydrogenated rosin AX-E 16.82%

[0055] Glutaric acid 1.20%

[0056] Sebacic acid 0.80%

[0057] Diethylamine hydrobromide 1.00%

[0058] Diphenylguanidine hydrobromide 1.00%

[0059] Cyclohexylamine hydrochloride 2.00%

[0060] Dibromobutenediol 0.70%

[0061] 0.30% hydrazine bromide

[0062] TX-10 phosphate 1.00%

[0063] Octadecyltrimethylammonium chloride 1.00%

[0064] 0.70% stannous chloride

[0065] Stannous oxalate 0.30%

[0066] BASF Ciba Antioxidant 1010 0.10%

[0067] Monoethanolamine 1.00%

[0068] Ethylene glycol monomethyl ether 2.00%

[0069] Propylene glycol ethyl ether 0.80%

[0070] N-methylpyrrolidone 1.20%

[0071] Tripropylene glycol butyl ether 0.80%

[0072] Fruity flavor masking agent 855 0.01%.

[0073] The preparation method of flux for solder wire used in soft soldering of nickel parts is as follows:

[0074] Glutaric acid, sebacic acid, diethylamine hydrobromide, diphenylguanidine hydrobromide, cyclohexylamine hydrochloride, dibromobutenediol, hydrazine bromide, stannous chloride, stannous oxalate, and BASF Ciba Antioxidant 1010 were sequentially weighed quantitatively and sealed in well-sealed solid reagent bottles to obtain compound solid additive A; TX-10 phosphate ester, octadecyltrimethylammonium chloride, 1.00% ethylene glycol monomethyl ether, N-methylpyrrolidone, and tripropylene glycol butyl ether were sequentially weighed quantitatively and stirred thoroughly at room temperature to ensure complete dissolution and uniform mixing of all materials. Filter the solution through a 200-mesh screen and quantitatively dispense it into well-sealed liquid reagent bottles to obtain compound mixed solution B; quantify and weigh monoethanolamine, 1.00% ethylene glycol monomethyl ether, and fruit-flavor masking agent 855 sequentially, and thoroughly stir, dissolve, mix, and dilute at room temperature, then quantitatively dispense it into well-sealed liquid reagent bottles to obtain compound diluted solution C; add refined hydrogenated rosin and Eastman fully hydrogenated rosin AX-E to the flux production reactor, heat to 150°C, and maintain the temperature while stirring until completely melted; then, while stirring... While slowly adding compound solid additive A, continue heating and stirring at a constant temperature of 150°C for 5-10 minutes to allow compound solid additive A to quickly disperse into the molten rosin. After melting 1 / 3 to 1 / 2 of the amount, slowly add compound mixed solution B while stirring, continue heating to 150°C and stirring for 10-20 minutes to ensure that compound solid additive A and compound mixed solution B are completely melted, dissolved, and mixed evenly in the molten rosin. Then, while stirring, slowly add compound diluted solution C and continue heating. The mixture is heated to 145℃ and stirred for 5-10 minutes to allow the diluted compound solution C to fully react and dissolve in the molten rosin containing the compound solid additive A and the compound mixed solution B, thus obtaining the initial flux compound material F. Finally, heating and stirring are stopped, and the mixture is allowed to stand for 5-10 minutes under its own residual heat, allowing the aqueous and oil phase components in the compound material F to settle and separate under gravity. The trace amount of aqueous phase precipitate at the bottom is removed, while the upper layer of rosin flux oil phase is retained, thus preparing the flux for soldering nickel parts.

[0075] The flux used for soldering nickel parts in this embodiment was prepared into a solder rod with a core of 2.0% SnAg3.0Cu0.5 by an extruder. Then, ultra-fine solder wire with a diameter of 0.1 mm was prepared by rolling, medium drawing, fine drawing and ultra-fine drawing. The properties such as spatter, solderability, spread rate, copper plate corrosion and surface insulation resistance after soldering were tested. The test results are shown in Table 1.

[0076] Example 2

[0077] A flux for soldering nickel components, comprising the following raw materials by weight percentage:

[0078] Eastman fully hydrogenated rosin AX-E 30.08%

[0079] Fully hydrogenated rosin AX-80 30.08%

[0080] Acrylic-modified hydrogenated rosin HM-604 15.04%

[0081] Methylsuccinic acid 1.50%

[0082] Glutaric anhydride 1.50%

[0083] Dodecanoic acid 1.00%

[0084] Isopropylamine hydrobromide 1.50%

[0085] 2-Ethylimidazolium hydrobromide 1.00%

[0086] Triethanolamine hydrochloride 1.50%

[0087] Diphenylguanidine hydrochloride 2.00%

[0088] Cyclohexylamine hydrochloride 4.00%

[0089] Chlorobridged anhydride 1.00%

[0090] Dibromosuccinic acid 1.00%

[0091] 0.50% oleyl alcohol polyoxyethylene ether

[0092] 0.50% hexadecyltrimethylammonium chloride

[0093] 0.50% stannous chloride

[0094] BASF Ciba Antioxidant 168 0.50%

[0095] BASF Ciba Antioxidant 1098 0.30%

[0096] Triethanolamine 2.00%

[0097] Tetrahydrofurfuryl alcohol 2.50%

[0098] Propylene glycol butyl ether 1.00%

[0099] Fruity flavor masking agent 851 0.20%

[0100] Jasmine essence 0.15%

[0101] Lemon fragrance essence 0.15%

[0102] Eucalyptus flavoring 0.10%

[0103] Breath of the Enchanted Forest Fragrance 0.40%

[0104] The preparation method of flux for solder wire used in soft soldering of nickel parts is as follows:

[0105] Methylsuccinic acid, glutaric anhydride, dodecanoic acid, isopropylamine hydrobromide, 2-ethylimidazolium hydrobromide, triethanolamine hydrochloride, diphenylguanidine hydrochloride, cyclohexylamine hydrochloride, chlorobrinesic anhydride, BASF Ciba Antioxidant 168, and BASF Ciba Antioxidant 1098 were sequentially weighed quantitatively and sealed in well-sealed solid reagent bottles to obtain compound solid additive A; dibromosuccinic acid, hexadecyltrimethylammonium chloride, stannous chloride, oleyl alcohol polyoxyethylene ether, 1.50% tetrahydrofurfuryl alcohol, and propylene glycol butyl ether were sequentially weighed quantitatively and stirred thoroughly at room temperature to ensure complete dissolution and mixing of all materials. The mixture was filtered through a 150-mesh screen and quantitatively dispensed into well-sealed liquid reagent bottles to obtain compound mixed solution B. Triethanolamine, 1.00% tetrahydrofurfuryl alcohol, propylene glycol butyl ether, fruit-scented masking agent 851, jasmine fragrance, lemon fragrance, eucalyptus fragrance, and "Breath of the Magic Forest" fragrance were sequentially and quantitatively weighed, thoroughly stirred, dissolved, mixed, and diluted at room temperature, and quantitatively dispensed into well-sealed liquid reagent bottles to obtain compound diluted solution C. Eastman fully hydrogenated rosin AX-E, fully hydrogenated rosin AX-80, and acrylic-modified hydrogenated rosin HM-604 were added... Inside the flux production reactor, the temperature is heated to 160°C and maintained at a constant temperature with stirring until completely melted. Then, while stirring, the compound solid additive A is slowly added, and the mixture is heated and stirred at a constant temperature of 150°C for 5-10 minutes to allow the compound solid additive A to quickly disperse into the molten rosin. After melting 1 / 3 to 1 / 2 of the mixture, the compound mixed solution B is slowly added while stirring, and the mixture is heated and stirred at a constant temperature of 150°C for 10-20 minutes to ensure that the compound solid additive A and the compound mixed solution B are completely and thoroughly melted and dissolved in the molten rosin. Finally, while stirring... While slowly adding the compound dilution solution C, continuously heat and stir at a constant temperature of 145℃ for 5-10 minutes to allow the compound dilution solution C to fully react and dissolve evenly in the molten rosin containing the compound solid additive A and the compound mixed solution B, thus obtaining the initial flux compound material F; finally, stop heating and stirring, and let it stand for 5-10 minutes under its own residual heat to allow the aqueous and oil phase components in the compound material F to achieve relative sedimentation and separation under gravity, remove the very small amount of aqueous phase precipitate at the bottom, and retain the upper rosin flux oil phase to prepare the solder wire flux for nickel soft soldering.

[0106] The flux used for soldering nickel parts in this embodiment was prepared into a solder rod with a core of 3.5% SnCu0.7 by an extruder. Then, a solder wire with a diameter of 1.0 mm was prepared by rolling, medium drawing, and fine drawing. The properties such as spatter, solderability, spread rate, copper plate corrosion, and surface insulation resistance after soldering were tested. The test results are shown in Table 1.

[0107] Example 3

[0108] A flux for soldering nickel components, comprising the following raw materials by weight percentage:

[0109] Hydrogenated water rosin 13.72%

[0110] Refined hydrogenated rosin 20.58%

[0111] Eastman fully hydrogenated rosin AX-E 13.72%

[0112] Acrylic-modified hydrogenated rosin HM-604 13.72%

[0113] Acrylic-modified hydrogenated rosin 3250 6.86%

[0114] Succinic anhydride 2.00%

[0115] Adipic acid 1.60%

[0116] 1.20% octanoic acid

[0117] Tridecanoic acid 1.20%

[0118] p-tert-butylimidazolium hydrobromide 1.00%

[0119] 2-Bromoethylamine hydrobromide 2.50%

[0120] Ethylenediamine hydrochloride 2.00%

[0121] Dimethylamine hydrochloride 1.50%

[0122] Dibromobutenediol 2.00%

[0123] 0.70% dibromoethylbenzene

[0124] Dibromosuccinic acid 0.80%

[0125] 2-Chlorosuccinic acid 1.50%

[0126] FS-3000 0.10%

[0127] Octadecyltrimethylammonium bromide 0.20%

[0128] 1.0% stannous chloride

[0129] Stannous oxalate 1.20%

[0130] Stannous methanesulfonate 0.80%

[0131] Antioxidant BHT 0.40%

[0132] Diethanolamine 1.50%

[0133] Diethanol monoisopropanolamine 2.00%

[0134] Methanol 1.00%

[0135] Propylene glycol propyl ether 2.00%

[0136] Diethylene glycol methyl ether 1.00%

[0137] Tripropylene glycol methyl ether 1.00%

[0138] Dipropylene glycol butyl ether 1.00%

[0139] Gardenia fragrance 0.10%

[0140] Peppermint flavoring 0.10%.

[0141] The preparation method of flux for solder wire used in soft soldering of nickel parts is as follows:

[0142] Succinic anhydride, adipic acid, octanoic acid, tridecanoic acid, p-tert-butylimidazolium hydrobromide, 2-bromoethylamine hydrobromide, ethylenediamine hydrochloride, dibromobutenediol, dibromoethylbenzene, 2-chlorosuccinic acid, stannous chloride, stannous oxalate, stannous methanesulfonate, and antioxidant BHT were sequentially weighed quantitatively and sealed in a well-sealed solid reagent bottle to obtain compound solid additive A; dimethylamine hydrochloride, dibromosuccinic acid, FS-3000, octadecyltrimethylammonium bromide, methanol, diethylene glycol methyl ether, tripropylene glycol methyl ether, and dipropylene glycol butyl ether were sequentially weighed quantitatively and stirred thoroughly at room temperature. All materials were thoroughly dissolved and mixed, filtered through a 120-mesh filter, and quantitatively dispensed into well-sealed liquid reagent bottles to obtain compound mixed solution B. Diethanolamine, diethanolamine monoisopropanolamine, propylene glycol propyl ether, gardenia fragrance, and peppermint fragrance were sequentially and quantitatively weighed, thoroughly stirred, dissolved, mixed, and diluted at room temperature, and quantitatively dispensed into well-sealed liquid reagent bottles to obtain compound diluted solution C. Hydrogenated water white rosin, refined hydrogenated rosin, Eastman fully hydrogenated rosin AX-E, acrylic acid-modified hydrogenated rosin HM-604, and acrylic acid-modified hydrogenated rosin 3250 were also prepared. Add the flux to the flux production reactor and heat to 160°C, maintaining a constant temperature and stirring until completely melted. Then, while stirring, slowly add compound solid additive A, continuing heating and stirring at 150°C for 5-10 minutes to allow compound solid additive A to quickly disperse into the molten rosin. After melting 1 / 3 to 1 / 2 of the amount, slowly add compound mixed solution B while stirring, continuing heating and stirring at 150°C for 10-20 minutes to ensure that compound solid additive A and compound mixed solution B are completely and thoroughly melted and dissolved in the molten rosin. Then, while stirring... While stirring, slowly add the compound diluted solution C, continue heating and stirring at a constant temperature of 145℃ for 5-10 minutes, allowing the compound diluted solution C to fully react and dissolve evenly in the molten rosin containing the compound solid additive A and the compound mixed solution B, to obtain the initial flux compound material F; finally, stop heating and stirring, and let it stand for 5-10 minutes under its own residual heat, allowing the aqueous and oil phase components in the compound material F to achieve relative sedimentation and separation under gravity, removing the very small amount of aqueous phase precipitates at the bottom, and retaining the upper rosin flux oil phase, to prepare the solder wire flux for soft soldering of nickel parts.

[0143] The flux used for soldering nickel parts in this embodiment was prepared into a solder rod with a core of 2.5% Sn37.5PbA using an extruder. Then, solder wire with a diameter of 1.4 mm was prepared by large drawing, medium drawing, and fine drawing. The properties such as spatter, solderability, spread rate, copper plate corrosion, and surface insulation resistance after soldering were tested. The test results are shown in Table 1.

[0144] Example 4

[0145] A flux for soldering nickel components, comprising the following raw materials by weight percentage:

[0146] Hydrogenated water rosin 36.95%

[0147] Fully hydrogenated rosin AX-80 36.95%

[0148] Succinic anhydride 1.50%

[0149] Glutaric acid 2.00%

[0150] Glutaric anhydride 1.20%

[0151] Sebacic acid 1.80%

[0152] Dodecanoic acid 1.50%

[0153] Cyclohexylamine hydrobromide 0.80%

[0154] 0.20% n-Butyl monophenylamine hydrobromide

[0155] 1.00% dibromoethylbenzene

[0156] Dibromosuccinic acid 1.00%

[0157] 2,2-Dichlorosuccinic acid 1.50%

[0158] OP-10 2.00%

[0159] Hexadecyltrimethylammonium bromide 1.00%

[0160] Stannous oxalate 1.00%

[0161] Stannous methanesulfonate 1.00%

[0162] BASF Ciba Antioxidant 1010 0.50%

[0163] BASF Ciba Antioxidant 1076 0.30%

[0164] BASF Ciba Antioxidant B215 0.20%

[0165] Monoethanolamine 1.20%

[0166] Triisopropanolamine 1.80%

[0167] Diethanol monoisopropanolamine 2.00%

[0168] Propylene glycol monomethyl ether 2.00%

[0169] Lily fragrance essence 0.20%

[0170] Thyme flavoring 0.20%

[0171] Dream Island Fragrance 0.20%.

[0172] The preparation method of flux for solder wire used in soft soldering of nickel parts is as follows:

[0173] Succinic anhydride, glutaric acid, glutaric anhydride, sebacic acid, dodecanoic acid, cyclohexylamine hydrobromide, dibromoethylbenzene, 2,2-dichlorosuccinic acid, stannous oxalate, stannous methanesulfonate, BASF Ciba Antioxidant 1010, BASF Ciba Antioxidant 1076, BASF Ciba Antioxidant B215, and triisopropanolamine were sequentially weighed quantitatively and sealed in a well-sealed solid reagent bottle to obtain compound solid additive A; n-butyl monophenylamine hydrobromide, dibromosuccinic acid, OP-10, hexadecyltrimethylammonium bromide, and propylene glycol monomethyl ether were sequentially weighed quantitatively. The following steps were performed: 1. Measure and thoroughly stir at room temperature to ensure complete dissolution and uniform mixing of all materials. Filter the solution using a 180-mesh filter and quantitatively dispense into sealed liquid reagent bottles to obtain compound mixed solution B. 2. Sequentially weigh monoethanolamine, diethanolamine monoisopropanolamine, lily fragrance, thyme fragrance, and Dream Island fragrance. Dissolve, mix, and dilute the solution at room temperature. Quantitatively dispense the solution into sealed liquid reagent bottles to obtain compound diluted solution C. 3. Add hydrogenated water white rosin and fully hydrogenated rosin AX-80 to the flux production reactor and heat to 145℃. After complete melting by constant temperature heating and stirring, slowly add compound solid additive A while stirring, continue heating and stirring at 150°C for 5-10 minutes to allow compound solid additive A to quickly disperse into the molten rosin. After melting 1 / 3 to 1 / 2 of the amount, slowly add compound mixed solution B while stirring, continue heating and stirring at 150°C for 10-20 minutes to ensure that compound solid additive A and compound mixed solution B are completely and thoroughly melted and dissolved in the molten rosin. Then, slowly add compound dilute... Dissolve solution C, continuously heat and stir at a constant temperature of 145℃ for 5-10 minutes to allow the diluted compound solution C to fully react and dissolve evenly in the molten rosin containing compound solid additive A and compound mixed solution B, thus obtaining the initial flux compound material F; finally, stop heating and stirring, and let it stand for 5-10 minutes under its own residual heat to allow the aqueous and oil phase components in the compound material F to achieve relative sedimentation and separation under gravity, remove the very small amount of aqueous phase precipitate at the bottom, and retain the upper rosin flux oil phase to prepare the solder wire flux for nickel soft soldering.

[0174] The flux used for soldering nickel parts in this embodiment was prepared into a solder rod with a core of 1.2% Sn63PbA using an extruder. Then, solder wire with a diameter of 2.0 mm was prepared by large drawing, medium drawing, and fine drawing. The properties such as spatter, solderability, spread rate, copper plate corrosion, and surface insulation resistance after soldering were tested. The test results are shown in Table 1.

[0175] According to the relevant test methods specified in international standard IPC-TM-650, the above Examples 1-4 were tested for spatter rate, weldability, spread rate, copper plate corrosion, and surface insulation resistance after welding. The test results are shown in Table 1.

[0176] Table 1. Summary of Performance Tests for Solder Wire and Flux for Nickel Parts Soldering

[0177]

[0178]

[0179] As shown in Table 1, the flux for soldering nickel parts of the present invention belongs to the category of flux for halogenated high-activity solder wire, complies with RoHS 3.0 and REACH directives, is suitable for leaded and lead-free tin-based solders, and can be used to prepare solder wire products of various specifications and wire diameters. It has excellent wetting and solderability for nickel parts, the fumes generated during the soldering process have a pleasant aroma, good flux residue drying performance, bright and full solder joints, clean surfaces with little or no residue, good spot soldering and drag soldering performance, minimal spatter, minimal corrosion, spread rate >75%, and qualified electrical performance test results. It meets the technical requirements of the international standard IPC-TM-650, which has a surface insulation resistance >108Ω and electromigration IRfinal >IRinitial / 10, and no discoloration, corrosion, or filament growth.

[0180] The flux for soldering nickel parts in this invention belongs to the category of halogenated high-activity soldering flux. It can be prepared experimentally in the laboratory and directly put into production line operation. It is suitable for leaded and lead-free tin-based solders and can be used to prepare solder wire products of various specifications and wire diameters. It has excellent wetting and solderability on nickel and other metal parts. The fumes generated during the soldering process have a pleasant aroma. The flux residue has good drying performance. The solder joints are bright and full, with clean surfaces and little or no residue. There is less spatter and less corrosion. It meets the environmental requirements of EU RoHS 3.0 and REACH.

Claims

1. A soldering flux for soldering a nickel member, characterized by: The raw material composition is in percentage by weight: Compound binary organic carboxylic acid 2.0-8.0%, Compound ionic halogenated activator 1.0-10.0%, Compound covalent halogenated activator 1.0-5.0%, Compound surfactant 0.3-3.0%, Metal salt 0.5-3.0%, Antioxidant 0.1-1.0%, Organic alcohol amine 1.0-5.0%, Flavor masking agent 0.01-1.0%, Organic solvent 2.0-6.0%, Compound modified rosin resin balance; The compound binary organic carboxylic acid is a combination of two or more of methyl succinic acid, succinic anhydride, glutaric acid, glutaric anhydride, adipic acid, suberic acid, sebacic acid, dodecanedioic acid, and tridecanedioic acid; The compound ionic halogenated activator is a combination of two or more of cyclohexylamine hydrobromide, diethylamine hydrobromide, p-tert-butyl imidazole hydrobromide, diphenyl guanidine hydrobromide, 2-bromoethylamine hydrobromide, isopropylamine hydrobromide, 2-ethyl imidazole hydrobromide, n-butyl monophenylamine hydrobromide, cyclohexylamine hydrochloride, dimethylamine hydrochloride, ethylenediamine hydrochloride, triethanolamine hydrochloride, and diphenyl guanidine hydrochloride; The compound covalent halogenated activator is a combination of two or more of chloro-bridged anhydride, dibromo-butene diol, dibromoethylbenzene, hydrazine bromide, dibromo succinic acid, 2,2-dichlorosuccinic acid, and 2-chlorosuccinic acid; The compound surfactant is a combination of non-ionic surfactant and ionic surfactant or a combination of non-ionic fluorocarbon surfactant and ionic surfactant; The metal salt is one or a combination of two or more of stannous chloride, stannous oxalate, and stannous methylsulfonate; The organic alcohol amine is one or a combination of two or more of monoethanolamine, diethanolamine, triethanolamine, triisopropanolamine, and diethanol mono-isopropanolamine; The organic solvent is one or a combination of two or more of methanol, tetrahydrofurfuryl alcohol, ethylene glycol monomethyl ether, propylene glycol monomethyl ether, propylene glycol ethyl ether, propylene glycol propyl ether, propylene glycol butyl ether, diethylene glycol methyl ether, tripropylene glycol methyl ether, tripropylene glycol butyl ether, dipropylene glycol butyl ether, and N-methyl pyrrolidone.

2. A method of preparing a flux for soldering nickel parts with solder wire according to claim 1, characterized in that The method steps are as follows: (1) Mix the solid binary organic carboxylic acid, a part of the covalent halogenated activator, a part of the ionic halogenated activator, the metal salt, and the antioxidant, then package them in a solid reagent bottle for later use, to obtain a compound solid additive A; (2) Put a part of the organic solvent into a reaction container, then add a part of the solid covalent halogenated activator, a part of the solid ionic halogenated activator, a part of the liquid covalent halogenated activator, a part of the ionic halogenated activator, and the compound surfactant into the reaction container, fully stir at room temperature to make each material fully dissolved and mixed uniformly, filter through a filter screen to obtain a mixed solution, then package the mixed solution in a liquid reagent bottle for later use, to obtain a compound mixed solution B; (3) The remaining organic solvent is loaded into the reaction vessel, and then the organic alcohol amine, the taste masking agent, the remaining liquid covalent halogenated activator, and the remaining liquid ionic halogenated activator are loaded into the reaction vessel, and the mixture is stirred and dissolved at room temperature to obtain a fully dissolved, mixed, and uniform dilution liquid. The dilution liquid is packaged in a liquid reagent bottle for use, and a complex dilution solution C is obtained; (4) The complex modified rosin resin is added to the flux production reactor and heated and stirred at a constant temperature until completely melted; (5) The complex solid flux A prepared in step (1) is slowly added to the melted complex modified rosin resin in step (4) while stirring, and the heating and constant temperature stirring are continued to quickly disperse the complex solid flux A into the molten rosin, and a complex material D is obtained; (6) The complex mixed solution B prepared in step (2) is slowly added to the complex material D in step (5) while stirring, and the heating and constant temperature stirring are continued to completely and fully melt and dissolve the complex solid flux A and the complex mixed solution B in the molten rosin, and a complex material E is obtained; (7) The complex dilution solution C prepared in step (3) is slowly added to the complex material E in step (6) while stirring, and the heating and constant temperature stirring are continued until the complex dilution solution C and the complex material E are fully reacted and dissolved and mixed uniformly, and a complex material F is obtained; (8) Stop heating and stirring, and let the complex material F prepared in step (7) stand for 5-10 minutes under its own residual heat conditions, so that the water phase and oil phase components in the complex material F are separated by gravity, the bottom layer of the settled water phase is removed, and the upper layer of the oil phase is retained to obtain the soldering flux for soft soldering of nickel parts.

3. A method of preparing a flux for soldering nickel parts with solder wire according to claim 2, characterized in that The prepared soldering flux for soft soldering of nickel parts is packaged into the core of a lead or lead-free tin rod by an extruder device to prepare a solder wire product.

4. The method of preparing a flux for soldering nickel parts according to claim 2, wherein The heating temperature of the complex modified rosin resin in step (4) is 150±10℃; the heating temperature for preparing the complex material D in step (5) is 150±10℃; the heating temperature for preparing the complex material E in step (6) is 150±10℃; and the heating temperature for preparing the complex material F in step (7) is 145±5℃.

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