A soldering high-wettability brass rod and a preparation method and application thereof

Abstract

The application discloses a kind of welding high wettability brass rod and its preparation method and application, the brass rod includes the following mass percentage components, Cu:57-61%, Pb:1.0-2.0%, Al:0.1-0.4%, Fe:0.1-0.3%, B:10-20ppm, Sn<0.5%, Ni<0.1%, the balance is Zn and inevitable impurities;The welding high wettability brass rod includes Fe3Al, FeB and Al2B crystal nucleus particle, the diameter of the crystal nucleus particle is 1~5nm.The application controls the composition, size and interplanar distance of crystal nucleus particle in rod, controls the welding wettability of brass rod, and subsequently develops suitable welding cooling process, by appropriately extending the air cooling time of brass welding cooling process, so that the welding structure is in nascent state, and then the processing performance, welding performance, corrosion and electrochemical performance are guaranteed, and has wide application prospect in the preparation of electronic appliances, instruments and other devices.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of metallurgical materials, and particularly relates to a high-wetting brass rod for welding, a preparation method and application thereof. BACKGROUND

[0002] With the development of society and the improvement of people's living standards, the demand for the application of copper alloys is increasing, and the environmental performance of material application is also increasingly valued. Lead brass is widely used in water heating, plumbing, electrical appliances, instruments, equipment manufacturing and many other industries due to its excellent mechanical properties, cutting performance, corrosion resistance and forming performance.

[0003] However, during the welding process of brass and red copper, or stainless steel, the welding is often not tight, and the problems of easy disconnection, air leakage and liquid leakage in the sealing test often occur. The existence of this problem causes great safety hazards to air conditioning refrigeration pressure sealing, electrical performance connection and equipment structure support. Improving poor welding is an urgent task for material workers.

[0004] Patent document CN113814510B discloses a laser welding process for brass and steel, which comprises: preparing brass and steel workpieces for welding; galvanizing the surface of the steel; arranging the brass plate and the galvanized steel plate together, using laser brazing, concentrating the laser energy mainly on the brass side, melting the brass into a liquid state, and keeping the steel in a solid state, using the molten liquid brass to infiltrate the steel interface to form a brazing joint; this method uses a deep penetration welding mechanism on the brass side and a brazing mechanism on the steel side, uses a swing welding method, and adjusts the appropriate defocusing amount to spread the liquid brass on the steel surface, achieving flat, firm and uniform welding of brass and steel.

[0005] Patent document CN103753021A discloses a laser welding method for red copper and brass, which comprises the following steps: cleaning the red copper and brass to be welded; machining a welding opening on the welding part of the brass to be welded; butting and fixing the brass and red copper to be welded at the welding opening; applying a layer of intermediate material on the welding opening of the brass by laser cladding; laser welding the red copper and brass at the intermediate material site; and naturally cooling to complete the preparation. The present application uses Ni-based alloy material as the intermediate material, supplements Si, B and other elements in the Ni-based alloy material to improve the surface quality of the intermediate material, fills the depression caused by the evaporation of Zn element in the laser cladding process of brass, and uses laser power density that is much lower than the laser power density used in laser welding in the laser cladding process, which can inhibit the dezincification of brass and ensure the welding quality of brass material.

[0006] Although the prior art has studied how to improve the welding quality of brass and other metals, the prior art has less research on improving the brass raw material itself to have better welding performance. In addition, high temperature heat flow will be used in the welding process to melt the welding rod, so that the metals to be welded are combined under the adhesion of the solder, but high temperature will cause the organization of the metal to be welded to change, such as abnormal grain growth, abnormal proliferation of dendritic organization, boundary overburning and surface dezincification, etc., which seriously affects its welding performance.

[0007] Therefore, it is an urgent task for material workers to develop a brass rod with excellent welding performance for electronic appliances, hardware and bathroom industries to solve the welding problem of existing lead brass. SUMMARY

[0008] The purpose of the present application is to provide a high-wetting brass rod for welding and its preparation method and application. The brass rod has fine and uniform grain structure, smooth cutting surface, low roughness, and good mirror effect, and has good welding performance for subsequent processing.

[0009] The first aspect of the present application provides a high-wetting brass rod for welding, comprising the following components by mass percentage: Cu: 57-61%, Pb: 1.0-2.0%, Al: 0.1-0.4%, Fe: 0.1-0.3%, B: 10-20ppm, Sn <0.5%, Ni <0.1%, the balance being Zn and unavoidable impurities; the high-wetting brass rod for welding comprises Fe3Al, FeB and Al2B crystal nucleus particles, and the diameter of the crystal nucleus particles is 1-5nm.

[0010] The present application controls the composition and size of the crystal nucleus (crystallization core) particles to regulate the welding wetting performance of the brass rod. Fe3Al, FeB and Al2B as crystal nucleus particles can provide a large number of nucleation sites, thereby refining the structure of the brass. This refining effect helps to improve the microstructure of the brass, making its surface smoother, and thus improving the wettability of the brass with other metals or materials.

[0011] The smaller crystal nucleus particles can generate more fine grains when growing, thus obtaining more compact material organization, and the fine grain polycrystal boundary organization surface can absorb more molten liquid flow, and by improving the strength and toughness, sufficient high-temperature softening resistance performance is obtained, the wetting angle is reduced and the wetting performance is improved, therefore, the diameter of the crystal nucleus particles is controlled below 5nm. For the crystal nucleus particles less than 1nm, only those embryos with a size equal to or greater than a certain critical size can stably exist and spontaneously grow by overcoming the increase of surface energy with more energy, therefore, the diameter of the crystal nucleus particles is controlled above 1nm.

[0012] Preferably, the crystal nucleus particles satisfy: 0.15nm < crystal face distance < 0.2nm in the (111) closest packing face direction; 0.2nm < crystal face distance < 0.25nm in the (110) face direction; and 0.2nm < crystal face distance < 0.25nm in the (100) face direction; and the number of crystal nucleus particles per unit area in the closest packing direction is 2000-6000 / mm 2 .

[0013] The size of the crystal face distance affects the arrangement density and stability of atoms on the crystal face. The face density of the crystal face with larger crystal face distance is higher, that is, the number of atoms per unit area is more, which is beneficial to the adsorption and arrangement of atoms, thus possibly promoting the growth of the crystal. In order to obtain more refined grains, promote the flow of the welding liquid in the welding process, the smaller the crystal face distance, the higher the density of the crystal, the greater the hardness and strength of the crystal, the shape of the stable material welding process is avoided, and the problems of debonding and cracking are avoided. At the same time, the present application combines the requirement of ultra-fine grain size of 5um or less and the size limitation requirement of the crystal nucleus particle growth, and finally controls the crystal face distance in the above range.

[0014] Preferably, in the welding high-wetting brass rod, the mass ratio of Fe, Al and B is 20000-30000:30000-40000:1. According to the optimal element ratio of Fe3Al, FeB and Al2B crystal nucleus particles, the ratio range of the related elements is determined, and excessive iron element will form the oxide Fe2O3 of elemental iron, which affects the bonding degree of welding. Excessive aluminum content will form the oxide Al2O3 of aluminum, which affects the compactness of welding, causes debonding and too much slag. Excessive boron content will cause the existence of boron oxide B2O3, which causes the risk of cracking in the welding process and the bonding degree of welding. Too low of an element will cause abnormality of other related elements, and finally cause welding abnormality. More preferably, in the welding high-wetting brass rod, the mass ratio of Fe, Al and B is 25000-30000:34000-40000:1.

[0015] Preferably, the roughness of the high-wettability brass rod after welding is less than or equal to 0.05 um. The present application controls the roughness of the brass rod to be less than or equal to 0.05 um, so that a better mirror effect can be obtained, the surface of the rod is very smooth, the welding process can be well vented and de-sludging, and the wettability is improved.

[0016] Preferably, the wetting angle of the high-wettability brass rod during welding is 5-7°. If the wetting angle is less than 5°, the solder is too thin and too much spread, which causes the shrinkage cracking problem of the welding layer. If the wetting angle is greater than 7°, the soldering is prone to stacking problems, and the soldering is prone to slag inclusion and unstable wetting, which causes air leakage problems.

[0017] The second aspect of the present application provides a preparation method of the high-wettability brass rod, which comprises the following steps: batching, melting and casting, wire drawing, annealing and grinding.

[0018] In the melting and casting process, the refining agent is a mixture of potassium fluoroborate, potassium fluorotitanate and potassium fluorosilicate.

[0019] In the melting and casting process, secondary water ring cooling is used, the temperature of the rod at the outlet of the crystallizer is 550-650 DEG C, and the temperature of the rod after secondary water ring cooling is 15-30 DEG C.

[0020] On the basis of the refining agent, the present application controls the melting and casting process to obtain the crystal nucleus particles with the above-mentioned size and interplanar distance. The crystal nucleus particles combined with the B element in the refining agent, the melting and casting temperature and the cooling speed obtain a certain supercooling degree, control the grain production, and obtain the required grain size and interplanar distance.

[0021] The refining agent is mainly used for refining the grain structure of brass. The refining agent of the present application enters the copper water to form smaller Fe3Al, FeB and Al2B crystal nucleus particles, more fine grains can be produced, so that a more dense material structure can be obtained, more molten liquid flow can be adsorbed, the strength, toughness and high-temperature softening resistance of the prepared material can be improved, the wetting angle can be reduced and the wettability can be improved. In addition, the crystal nucleus particles of the refining agent of the present application can inhibit the growth of grains during the welding process.

[0022] The existing refining agents such as boron-aluminum alloy, boron-iron, potassium fluoroborate and boron powder have blind areas in the refining process, and the problems of poisoning of the refining agent and poor quality of the refined crystal nucleus particles are prone to occur. The refining agent of the present application is a mixture of potassium fluoroborate, potassium fluorotitanate and potassium fluorosilicate. The addition of fluorine salt can reduce the triggering problem of the core reaction of the crystal nucleus particles, so that the grains are more fine and uniform, and the above-mentioned problems can be overcome.

[0023] In addition, the refiner of the present application can homogenize the distribution of lead particles, and improve the comprehensive mechanical properties of the material. Due to the refinement of the crystal grains, the interface channels increase, and the second phase cutting particles Pb phase can be more uniformly distributed in the matrix and the grain boundary position, so that the processing product is more smooth, the chip is more fine, and the processing surface roughness is lower.

[0024] Preferably, in the refiner, the mass ratio of potassium fluoborate, potassium fluotitanate and potassium fluorosilicate is 6-8:1-2:2-4. The refiner with this composition has better refining effect, and can better improve the comprehensive properties of the material such as wettability, strength and toughness.

[0025] Preferably, the addition amount of the refiner is 0.02-0.05% of the total mass of the raw materials. The present application controls the formation of Fe3Al, FeB and Al2B crystal nucleus particles in the alloy bar by controlling the composition and addition amount of the refiner to provide a large number of nucleation sites, thereby refining the structure of the brass and avoiding the presence of Fe2O3, Al2O3 or B2O3 oxides to affect the welding performance of the material.

[0026] More preferably, the addition amount of the refiner is 0.03% of the total mass of the raw materials.

[0027] Preferably, the secondary water ring cooling is carried out in a water ring cooling device, the water ring cooling device comprises a first water ring and a second water ring with a spacing of 50-200mm, the first water ring and the second water ring are provided with water inlets, and the inner wall of the water ring is provided with a plurality of water spraying holes with downward inclined water spraying direction. During the cooling process, the cooling water is sprayed out from the water spraying holes to cool the bar which passes through the center of the first water ring and the second water ring in sequence.

[0028] Preferably, the water spraying holes are circumferentially arranged along the inner wall of the water ring.

[0029] Preferably, during the secondary water ring cooling process, the primary cooling water flow rate is 10-40m 3 / h, the secondary cooling water flow rate is 1-30m 3 / h, the water pressure is 0.4-0.6MPa, the water inlet temperature is 20-40℃, and the water outlet temperature is 40-60℃.

[0030] Preferably, in the melting and casting process, the raw materials are added according to the alloy composition ratio, and then heat preservation is carried out after melting. The heat preservation temperature is 980-1020℃, the heat preservation time is 3-5min, after the heat preservation is completed, the furnace temperature is increased to 1050-1080℃, after refining and slag removal, the temperature is adjusted to 1000-1030℃, the above-mentioned refiner is added, stirring is carried out, and after the spectral test composition is qualified, traction casting is carried out, the traction speed is 220-400mm / min, and the traction temperature is 1030-1040℃.

[0031] Preferably, the annealing temperature in the stress relief annealing process is 280-350 DEG C, and the annealing time is 2-4h. The stress relief annealing process of the application adopts uniform annealing to eliminate the structure defects.

[0032] Preferably, the roughness of the rod is controlled to be below 0.05um in the grinding process. After the annealing process of the rod is completed, the surface roughness is high, which will become a shelter for pores and slag in the welding process, so the mirror level rod needs to be obtained. The rod surface is polished by grinding and polishing treatment, so that the rod surface is very smooth, the welding process can well exhaust and deslag, and the effect of improving the wetting property is achieved. The roughness of the rod is less than or equal to 0.05um, and a good mirror effect can be obtained.

[0033] The third aspect of the application provides the application of the high-wetting brass rod in the preparation of electronic appliances, instruments or hardware and bathroom accessories. The brass rod of the application has good welding performance under the premise of ensuring the comprehensive performance of the lead brass, and has a wide application prospect in electronic appliances, instruments or hardware and bathroom.

[0034] Preferably, in the preparation of the above-mentioned electronic appliances, instruments or hardware and bathroom accessories, the brass rod is welded with other metal materials, and the obtained welded material is water-cooled after air-cooling for 10-25s.

[0035] In the welding process, high-temperature heat flow is used to melt the welding rod, so that the metals to be welded are combined under the adhesion of the welding material. However, high temperature can also cause the structure of the welded metal to change, such as abnormal grain growth, abnormal proliferation of dendritic structure, overburning of the interface, and dezincification of the surface. By developing a suitable welding cooling process, the welding structure can be in the nascent state, the processing performance, the welding performance, the corrosion and the electrochemical performance are guaranteed.

[0036] The time of the welding cooling process can cause the change of the structure. The prior art usually adopts a short air-cooling time (about 5s) for welding, which makes the structure of the welding material at high temperature mainly be coarse beta phase grain structure. At this time, the rapid cooling will cause the coarse and brittle beta phase to remain in the room temperature structure, and the stress of the material is also increased, which finally causes the cracking risk of the material.

[0037] The application prolongs the air-cooling time in the welding cooling process to 10-25s, and then performs rapid cooling, so that a good fine grain structure can be obtained, the performance of the brass structure in the welding process is avoided to be deteriorated, and the stability of the welding is improved.

[0038] Compared with the prior art, the application has at least the following beneficial effects:

[0039] (1) The present application can control the grain production and obtain the required grain size and interplanar distance by adding special refiner in the melting and casting process and controlling the melting and casting process, combining the B element compound nucleus particles in the refiner, the melting and casting temperature and the cooling speed to obtain certain supercooling degree.

[0040] (2) The present application can make the rod material have good mirror surface effect after the rod material annealing process is completed, so that it can well exhaust and discharge slag in the welding process, and achieve the effect of improving the wetting performance.

[0041] (3) The present application develops a suitable welding cooling process in the process of welding brass, prolongs the air cooling time of the brass welding cooling process, so that the welding structure is in the nascent state, and then the processing performance, welding performance, corrosion and electrochemical performance are guaranteed. BRIEF DESCRIPTION OF DRAWINGS

[0042] Figure 1 It is a schematic diagram of the secondary water ring cooling device in the embodiment of the present application; wherein 1 is a first water ring; 2 is a second water ring.

[0043] Figure 2 It is a microstructure diagram of the brass rod material prepared in Example 1.

[0044] Figure 3 It is the wetting angle of the brass rod material prepared in Example 1 when welding.

[0045] Figure 4 It is a microstructure diagram of the brass rod material prepared in Example 2.

[0046] Figure 5 It is the wetting angle of the brass rod material prepared in Example 2 when welding.

[0047] Figure 6 It is a microstructure diagram of the brass rod material prepared in Example 3.

[0048] Figure 7 It is the wetting angle of the brass rod material prepared in Example 3 when welding.

[0049] Figure 8 It is a microstructure diagram of the brass rod material prepared in Comparative Example 1.

[0050] Figure 9 It is the wetting angle of the brass rod material prepared in Comparative Example 1 when welding. DETAILED DESCRIPTION

[0051] Example 1

[0052] The alloy composition of this embodiment is: Cu 59.50%, Pb 1.50%, Al 0.35%, Fe 0.25%, Sn 0.2%, Ni 0.04%, the balance being Zn, and the content of B is 11 ppm. A special refiner X for brass (70% potassium fluoborate, 20% potassium fluorosilicate, and 10% potassium fluorotitanate) is configured, and the addition amount of the refiner X is 0.03% of the total amount of the furnace charge.

[0053] In the production of a 3t power frequency furnace The cast blank is subjected to skinning production Rod.

[0054] The casting process is as follows:

[0055] 1. The 2.5t processed recycled raw materials are added into the power frequency furnace in two batches. In the first time, 1.5t of the recycled materials are added into the furnace, and after the recycled materials are completely melted, the remaining 1t of the processed recycled materials is added into the furnace. After the recycled materials are completely melted, the temperature is set at 980-1020°C.

[0056] 2. After the holding is finished, the furnace temperature is increased to 1050-1080°C, and the fire is sprayed for about 1min. The refining agent is added into the furnace, and then stirred. After the stirring is finished, the slag in the furnace is cleaned, the temperature is adjusted to 1000-1030°C, the sample is taken for spectral testing, and 800g of the refiner X is pressed into the furnace by using a press spoon. After 1min of stirring, the holding is static, and the spectral testing is qualified. The traction casting can be arranged.

[0057] 3. After the spectral testing is qualified, the traction is arranged, the traction speed is 320mm / min, the traction temperature is 1030-1040°C, and the ingot specification In the casting process of this embodiment, the secondary water ring cooling is adopted, the primary cooling water flow is 25m 3 / h, the secondary cooling water flow is 25m 3 / h, the water pressure is 0.4-0.6MPa, the water inlet temperature is 20-40°C, the water outlet temperature is 40-60°C, the continuous casting rod outlet temperature of the crystallizer is 550-650°C, and the temperature of the cast rod after the secondary cooling is 15-30°C.

[0058] The schematic diagram of the secondary water ring cooling device in the embodiment of the application is shown in Figure 1 The secondary water ring cooling device includes a first water ring and a second water ring, and the distance between the first water ring and the second water ring is 150mm. A plurality of water spraying holes with a downward inclined water spraying direction are arranged on the inner walls of the first water ring and the second water ring, and the water spraying holes are arranged along the circumferences of the water ring inner walls. In the cooling process, the primary water enters the water chamber from the water inlet 1, and the primary cooling of the continuous casting rod is performed by the water outlet from the water spraying holes on the water outlet 1. The secondary water enters the water chamber from the water inlet 2, and the secondary cooling of the continuous casting rod is performed by the water outlet from the water spraying holes on the water outlet 2.

[0059] Wire drawing process:

[0060] The drawn blank is directly put on a straight drawing machine to be peeled to obtain a semi-finished product, i.e.

[0061] Stress relief annealing:

[0062] The rod is heated and annealed to relieve stress, and the annealing temperature is 300°C and the time is 3h.

[0063] Grinding process:

[0064] The annealed and ground rod is continuously polished by a polishing wheel, and the roughness of the polished rod is 0.05um or less.

[0065] Inspection and storage.

[0066] Customer welding: the actual welding process, and the cooling temperature needs to be determined according to the actual efficiency requirement, and the air cooling time is extended to 15s for water cooling.

[0067] The alloy composition and the microstructure parameters of the product of the embodiment are shown in Table 1 and Table 2, respectively.

[0068] Spectrum composition: Cu 59.50%, Pb 1.50%, Al 0.35%, Fe 0.25%, Sn 0.2%, Ni 0.04%, the balance being Zn, and the content of B being 11ppm. The cutting performance of the finished product produced by the above process is 87% of that of HPb63-3, the cutting end morphology is small crescent, the machining surface roughness is 0.05um, the mirror effect is obvious, and the solder wetting effect is good. The particle diameters of Fe3Al, FeB and Al2B are 2nm, the crystal face distance in the closest packed (111) plane direction of the brass is 0.15nm, the number of particles per unit area in the <110> closest packed direction is 4500 / mm 2 2nm; and the crystal face distance in the (100) plane direction is 0.2nm, which ensures sufficient solid solution or nucleation and growth of the second phase crystal nucleus particles.

[0069] Figure 2 The microstructure of the brass rod prepared in Example 1 is shown in Table 1 and Table 2, respectively. Figure 2 As can be seen, the grain structure of the brass rod prepared in the embodiment is relatively fine, composed of α phase and β phase, and there is local dendrite, which may be due to the influence of certain temperature gradient in the cooling process, and the grain size is generally uniform.

[0070] Figure 3 The wetting angle of the brass rod prepared in Example 1 during welding is 5.17°, as shown in Table 1 and Table 2. Figure 3 As can be seen, after welding, the solder and the substrate are combined in a relatively dense manner, and the solder wetting angle is gentle and uniform.

[0071] Example 2

[0072] The alloy composition of this example is: Cu 60.50%, Pb 1.70%, Al 0.38%, Fe 0.27%, Sn 0.2%, Ni 0.04%, Zn balance, and the content of B is 12 ppm. A special refiner X for brass (70% potassium fluoborate, 20% potassium fluorosilicate, and 10% potassium fluorotitanate) is used, and the addition amount of the refiner X is 0.03% of the total amount of the charge.

[0073] In the production of a 3t power frequency furnace The cast blank is subjected to skinning production Rod.

[0074] Melting and casting process:

[0075] 1. The 2.5t processed scrap raw material is added into the power frequency furnace in two batches, 1.5t of scrap is added into the furnace at the first time, and after the scrap is completely melted, the remaining 1t of processed scrap is added into the furnace, after the scrap is completely melted, the temperature is set at 980-1020°C.

[0076] 2. After the holding is finished, the furnace temperature is increased to 1050-1080°C, and the flame is sprayed for about 1min, the refining agent is added into the furnace, then stirred, after the stirring is finished, the slag in the furnace is cleaned, the temperature is adjusted to 1000-1030°C, the sample is taken for spectral testing, at the same time, 800g of the refiner X is pressed into the furnace by using the press spoon, stirred for 1min, then held still, and the spectral testing is qualified to arrange the traction casting.

[0077] 3. The spectral testing composition is qualified, the traction is arranged, the traction speed is 290mm / min, the traction temperature is 1030-1040°C, and the ingot specification In the casting process of this example, the secondary water ring cooling is used, the primary cooling water flow is 30m 3 / h, the secondary cooling water flow is 25m 3 / h, the water ring spacing is 150mm, the water pressure is 0.4-0.6MPa, the water inlet temperature is 20-40°C, the water outlet temperature is 40-60°C, the continuous casting rod temperature at the crystallizer outlet is 550-650°C, and the casting rod temperature after the secondary cooling is 15-30°C.

[0078] Drawing process:

[0079] The traction blank is directly put on the straight drawing machine to peel off the skin and output the semi-finished product, that is

[0080] Stress relief annealing:

[0081] The rod is subjected to stress relief heating annealing, and the annealing temperature is 300°C, and the time is 3h.

[0082] Grinding process:

[0083] After annealing, the grinding rod is continuously polished by a polishing wheel, and the roughness of the polished rod is below 0.045um.

[0084] Inspection and storage.

[0085] Customer welding: actual welding process, cooling temperature needs to be determined according to actual efficiency requirements, and the air cooling time is extended to 19s for water cooling.

[0086] The alloy composition and microstructure parameters of the product of the embodiment are shown in Table 1 and Table 2, respectively.

[0087] Spectrum composition: Cu 60.50%, Pb 1.70%, Al 0.38%, Fe 0.27%, Sn 0.2%, Ni 0.04%, Zn balance, and the content of B is 12ppm. The cutting performance of the finished product produced by the above process is 90% of that of HPb63-3, the cutting end morphology is small crescent, the machining surface roughness is 0.045um, the mirror effect is obvious, and the solder wetting effect is good. The diameters of Fe3Al, FeB and Al2B particles are 3nm, the crystal face distance in the closest packed (111) plane direction of brass is 0.18nm, the number of particles per unit area in the <110> closest packed direction is 5000 / mm2, the crystal face distance in the (110) plane direction is 0.15nm, and the crystal face distance in the (100) plane direction is 0.15nm, which ensures sufficient solid solution or nucleation and growth of the second phase crystal nucleus particles. 2

[0088] Figure 4 The microstructure metallographic diagram of the brass rod prepared in Example 2 is shown in Figure 2. Figure 4 As can be seen from the diagram, the grain structure of the brass rod prepared in the embodiment is relatively fine, composed of α phase and β phase, mainly in the form of short rods and islands, and uniformly distributed.

[0089] Figure 5 The wetting angle (6.87°) of the brass rod prepared in Example 2 during welding is shown in Figure 3. Figure 5 As can be seen from the diagram, after welding, the solder and the substrate are combined in a relatively dense manner, and the solder wetting angle is gentle and uniform.

[0090] Example 3

[0091] The alloy composition of the embodiment is Cu 57.50%, Pb 1.90%, Al 0.37%, Fe 0.28%, Sn 0.2%, Ni 0.02%, Zn balance, and the content of B is 10ppm. A special brass refiner X (potassium fluoroborate 70%, potassium fluorosilicate 20%, and potassium fluorotitanate 10%) is configured, and the addition amount of the refiner X is 0.03% of the total amount of the furnace charge.

[0092] ​In 3t power frequency furnace production The casting blank is stripped Bar.

[0093] Melting process:

[0094] 1. Add 2.5t of processed return material to the power frequency furnace in two batches. Add 1.5t of return material to the furnace first, and then add the remaining 1t of processed return material after the return material is completely melted. After the return material is completely melted, perform heat preservation with the temperature set at 980-1020℃.

[0095] 2. After the heat preservation is completed, increase the furnace temperature to 1050-1080℃, spray fire for about 1min, add the refining agent to the furnace, then stir, clean the slag in the furnace, adjust the temperature to 1000-1030℃, take samples for spectral testing, and use a press spoon to press 800g of refining agent X into the furnace, stir for 1min, then perform heat preservation and static, and arrange for traction casting after the spectral test is qualified.

[0096] 3. After the spectral test is qualified, arrange for traction at a speed of 360mm / min and a temperature of 1030-1040℃, and the ingot specification In the casting process of this embodiment, two-stage water ring cooling is used, the first cooling water flow is 35m 3 / h, the second cooling water flow is 30m 3 / h, the water ring spacing is 150mm, the water pressure is 0.4-0.6MPa, the water inlet temperature is 20-40℃, the water outlet temperature is 40-60℃, the continuous casting bar outlet temperature of the crystallizer is 550-650℃, and the casting bar temperature after secondary cooling is 15-30℃.

[0097] Drawing process:

[0098] The traction blank is directly placed on the straight drawing machine for skinning to obtain a semi-finished product, that is

[0099] Stress relief annealing:

[0100] The bar is subjected to stress relief heating annealing at a temperature of 300℃ for 3h.

[0101] Grinding process:

[0102] The annealed and ground bar is subjected to continuous polishing treatment using a polishing wheel, and the roughness of the polished bar is 0.04um or less.

[0103] Inspection, storage.

[0104] Customer welding: In the actual welding process, the cooling temperature needs to be adjusted according to the actual efficiency requirement, and the air cooling time is extended to 21s for water cooling.

[0105] The alloy composition and microstructure parameters of the product of this embodiment are shown in Table 1 and Table 2, respectively.

[0106] Spectrum composition: Cu 57.50%, Pb 1.90%, Al 0.37%, Fe 0.28%, Sn 0.2%, Ni 0.02%, Zn balance, B content 10 ppm. The cutting performance of the finished product produced by the above process is 85% of that of HPb63-3, the cutting end morphology is small crescent, the machining surface roughness is 0.04 um, the mirror effect is obvious, and the solder wetting effect is good. The particle diameters of Fe3Al, FeB and Al2B are 4 nm, the crystal face distance in the closest packed (111) plane direction of the brass is 0.15 nm, and the number of particles per unit area in the <110> closest packed direction is 5200 / mm2. 2 The crystal face distance in the (110) plane direction is 0.17 nm, and the crystal face distance in the (100) plane direction is 0.17 nm, which ensures sufficient solid solution or nucleation and growth of the second phase crystal nucleus particles.

[0107] Figure 6 The microstructure metallographic diagram of the brass rod prepared in Example 3 is shown in Figure 2, which shows that the grain structure of the brass rod prepared in this embodiment is relatively fine, composed of α phase and β phase, mainly in the form of short rods and islands, and there are some fine dendrites in some parts, and the distribution is uniform. Figure 6 As can be seen from Figure 2, the grain structure of the brass rod prepared in this embodiment is relatively fine, composed of α phase and β phase, mainly in the form of short rods and islands, and there are some fine dendrites in some parts, and the distribution is uniform.

[0108] Figure 7 The wetting angle of the brass rod prepared in Example 3 during welding is 5.25°, as shown in Figure 3, which shows that after welding, the solder and the substrate are combined in a relatively dense manner, and the solder wetting angle is gentle and uniform. Figure 7 As can be seen from Figure 3, after welding, the solder and the substrate are combined in a relatively dense manner, and the solder wetting angle is gentle and uniform.

[0109] Comparative Example 1

[0110] The alloy composition of this comparative example is: Cu 58.50%, Pb 1.85%, Al 0.33%, Fe 0.20%, Sn 0.2%, Ni 0.02%, Zn balance.

[0111] In a 3t power frequency furnace, the casting billet is stripped to produce the rod.

[0112] Melting process:

[0113] 1. Add 2.5t of processing return material to the power frequency furnace in two batches, add 1.5t of return material to the furnace first, and then add the remaining 1t of processing return material to the furnace after the return material is completely melted, and then perform heat preservation with the temperature set at 980-1020°C.

[0114] ​2. After the holding, the furnace temperature is increased to 1050-1080°C, and the flame is sprayed for about 1 minute. Then the refining agent is added into the furnace, and stirred. After the stirring, the slag in the furnace is cleaned, the temperature is decreased to 1000-1030°C, and the sample is taken for spectrum test. Meanwhile, 800g of refining agent (95% boron powder and 5% iron powder) is pressed into the furnace by a press spoon, and stirred for 1 minute. Then the sample is held and tested by spectrum. If the spectrum test is qualified, the drawing is arranged.

[0115] 3. If the spectrum test is qualified, the drawing is arranged, the drawing speed is 360mm / min, the drawing temperature is 1030-1040°C, and the ingot size is

[0116] Drawing process:

[0117] The drawing blank is directly put on the straight drawing machine to peel the skin and get the semi-finished product, i.e.

[0118] Stress relief annealing:

[0119] The bar is heated and annealed by stress relief, the annealing temperature is 300°C, and the time is 3h.

[0120] Grinding process:

[0121] Inspection and storage.

[0122] Customer welding: the actual welding process, the cooling temperature needs to be determined according to the actual efficiency requirement, and the air cooling time is about 5s for water cooling.

[0123] The alloy composition and the microstructure parameters of the product of the comparative example are shown in Table 1 and Table 2, respectively.

[0124] Spectrum composition: Cu 58.50%, Pb 1.85%, Al 0.13%, Fe 0.1%, Sn 0.2%, Ni 0.02%, Zn balance. The cutting performance of the finished product produced by the above process is 90% of that of HPb63-3, the cutting end appearance is small crescent, the machining surface roughness is 0.7um, the mirror surface is seriously diffuse reflected, the mirror surface is blurred, and the welding wetting effect is poor. The particle diameter of Fe3Al, FeB and Al2B is 20nm, the crystal face distance of brass in the closest packed (111) direction is 0.5nm, the number of particles per unit area in the <110> closest packed direction is 1200 / mm 2 ; the crystal face distance in the (110) direction is 0.2nm; the crystal face distance in the (100) direction is 0.2nm, which ensures sufficient solid solution or nucleation and growth of the second phase crystal nucleus particles.

[0125] Figure 8 The microstructure metallographic diagram of the brass bar prepared in Comparative Example 1 is shown in Figure 8It can be seen that the metallographic interface grain structure of the brass rod prepared in the comparative example is coarse, composed of a phase and β phase, and mainly presents a large island grain morphology distribution.

[0126] Figure 9 The wetting angle (40.53°) of the brass rod prepared for the comparative example 1 when welding is obtained from Figure 9 It can be seen that after welding, the combination degree of the solder and the base body is relatively loose, and the solder has a significant problem of pores and slag, and the solder wetting angle is steep.

[0127] Table 1 alloy rod composition (wt%) of the examples and comparative examples of the present application

[0128]

[0129] Table 2 microstructure and properties of the alloy rod of the examples and comparative examples of the present application

[0130]

Claims

1. A soldering high-wettability brass rod material, characterized by, The welding high-wetting brass rod comprises the following components in percentage by mass: Cu: 57-61%, Pb: 1.0-2.0%, Al: 0.1-0.4%, Fe: 0.1-0.3%, B: 10-20ppm, Sn <0.5%, Ni <0.1%, and the balance of Zn and inevitable impurities; the welding high-wetting brass rod comprises Fe3Al, FeB and Al2B crystal nucleus particles, and the diameter of the crystal nucleus particles is 1-5nm.

2. The soldering high-wettability brass rod according to claim 1, characterized by, The crystal nucleus particle satisfies: 0.15 nm < crystal face distance < 0.2 nm in the (111) closest packing face direction; 0.2 nm < crystal face distance < 0.25 nm in the (110) face direction; and 0.2 nm < crystal face distance < 0.25 nm in the (100) face direction; and the number of crystal nucleus particles per unit area in the closest packing direction is 2000-6000 / mm 2 .

3. The soldering high-wettability brass rod according to claim 1, characterized by, The roughness of the high-wettability brass rod is less than or equal to 0.05 μm; and the wetting angle of the high-wettability brass rod during welding is 5-7 o .

4. The method of producing a soldering high-wettability brass rod according to any one of claims 1 to 3, characterized by, The method comprises the following steps: batching, melting and casting, wire drawing, annealing and grinding. In the melting and casting process, the refiner is a mixture of potassium fluoroborate, potassium fluorotitanate and potassium fluorosilicate. In the melting and casting process, secondary water ring cooling is adopted, the temperature of the rod at the outlet of the crystallizer is 550-650 DEG C, and the temperature of the rod after the secondary water ring cooling is 15-30 DEG C.

5. The preparation method according to claim 4, characterized in that, In the refiner, the mass ratio of potassium fluoroborate, potassium fluorotitanate and potassium fluorosilicate is 6-8:1-2:2-4, and the adding amount of the refiner is 0.02-0.05% of the total mass of the raw materials.

6. The preparation method according to claim 4, characterized in that, The secondary water ring cooling is carried out in a water ring cooling device, the water ring cooling device comprises a first water ring and a second water ring with a spacing of 50-200mm, the first water ring and the second water ring are provided with water inlets, and the inner wall of the water ring is provided with a plurality of water spraying holes with the water spraying direction inclined downward; during the cooling process, the cooling water is sprayed out from the water spraying holes to cool the rod which passes through the center of the first water ring and the second water ring in sequence.

7. The preparation method according to claim 4, characterized in that, The secondary water ring cooling process has a primary cooling water flow rate of 10-40 m 3 / h, a secondary cooling water flow rate of 1-30 m 3 / h, a water pressure of 0.4-0.6 MPa, an inlet water temperature of 20-40 DEG C, and an outlet water temperature of 40-60 DEG C.

8. The welding high-wetting brass rod according to any one of claims 1-3 is applied in the preparation of electronic appliances, instruments or hardware and bathroom accessories.

9. Use according to claim 8, characterized in that, During the application, the welding high-wetting brass rod is welded, and after the welding is completed, the obtained welded material is subjected to water cooling after air cooling for 10-25s.

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