CN1413797A - Expansion soldering method of aluminium-copper tube and active connection agent for the method and its making method - Google Patents

Abstract

The expansion brazing method of aluminum-copper pipe and the active connecting agent used in the method and its preparation method. The present invention relates to the connection method of aluminum-copper pipe and the active connecting agent used in the method and its preparation method. The active linking agent contains active nanometer powder, non-corrosion brazing flux, and adhesive components. The preparation method is to crush the active particles with a purity of 99.9% to 100% into nano powders with a particle size of 20nm to 100μm; mix. The brazing method of aluminum-copper tubes is to process the joints of aluminum tubes and copper tubes into conical surfaces (3), and then apply solder-free active linking agent on the conical surfaces, and heat them. During the heating process, the two ends of the welded tubes put pressure on. The bonding agent welds different metals and non-metals to produce less stress, lower welding temperature and lower pressure. By adopting the method of the invention to braze aluminum and copper pipes, the compactness of the brazing seam can reach more than 85%.

Description

The expansion method for brazing of aluminium-copper tube and be used for the active bridging agent and the method for making thereof of this method

Technical field: the present invention relates to the soldering connecting method of aluminium-copper tube, especially relating to no solder does not have the method for the quick brazed aluminum copper pipe of corrosion and is used for the active bridging agent of no solder of this method and the preparation method of this activity bridging agent.

Background technology: at present, air conditioner industry makes that the production cost is difficult to reduce owing to adopted a large amount of copper pipes on product.Be the target that people seek with aluminium for copper for many years, because the proportion of aluminium alloy is 2.7g/cm always ³, and the proportion of brass is 8.5g/cm ³, therefore will reduce product weight and cost effectively for copper with aluminium.But,, therefore to solve the problem that can aluminium, copper pipe link together between the two effectively for the key of copper with aluminium if will realize that fine and close to connect difficulty reliably bigger because aluminium, copper material physical property differs greatly.Though present conventional soldering interconnection technique has solved this problem, but because the effect of solder, brazing flux is to environmental protection, all cause certain harm to the operator, and have temperature height, big, the ineffective shortcoming of pressure, cause this conventional method for brazing not apply.

Summary of the invention: the present invention is the expansion method for brazing of a kind of aluminium-copper tube of development and active bridging agent and the method for making thereof that is used for this method, the stability that the viscosity that makes the active bridging agent of no solder have appropriateness is become reconciled makes brazing process speed fast, and it is little to produce stress, temperature required low, pressure is little.The active bridging agent of no solder of the present invention comprises following composition: active nano powder, non-corrosion type brazing flux, bonding agent, the part by weight of each composition close and are; Bonding agent: non-corrosion type brazing flux: active nano powder=(1～20): (1～5): (0～1), wherein the purity of active nano powder is 99.9%～100%, granularity is 20nm～100 μ m, when adopting granularity is that the active nano powder of 20nm～10 μ m is made into bridging agent, and its performance is better.Bonding agent is to be in harmonious proportion and to be made by water, organic cellulose, and the weight ratio of water and organic cellulose is 100: (0.1～5).The method for making of the active bridging agent of no solder of the present invention is: be that 99.9%～100% active particle is made the nanometer powder that granularity is 20nm～100 μ m through mechanical crushing or powder injection process with purity; Make bonding agent by water, organic cellulose mediation, the weight ratio of water and organic cellulose is 100: (0.1～5).Above two kinds of compositions and non-corrosion type brazing flux are mixed bonding agent: non-corrosion type brazing flux: active nano powder=(1～20): (1～5) by following part by weight relation: (0～1) makes it become the active bridging agent of no solder.The rapid expanding method for brazing of aluminum bronze insertion pipe of the present invention is: at first be processed into the conical surface 3 in the grafting joint of aluminum pipe 1 and copper pipe 2, to not have again on the faying face of the conical surface 3 that the active bridging agent 4 of solder is coated in aluminum pipe 1 and copper pipe 2 grafting joints, connect conventional brazing temperature heating then, P again exerts pressure at the two ends of two welded tubes in the time of heating process, make between aluminum pipe 1 and the copper pipe 2 and in brazing process, remain tight the contact, finish quick brazing process.The difference of the linear expansion coefficient of aluminum bronze makes between aluminum pipe 1 and the copper pipe 2 and keeps closely contacting when utilizing heating, and generation contacts pressure between faying face.In the time of in aluminum pipe 1 is inserted in copper pipe 2, the connection-peg of aluminum pipe 1 and copper pipe 2 is not processed the conical surface, the soldering of directly pegging graft.The thermal coefficient of expansion of aluminium produces contact pressure greater than the thermal coefficient of expansion of copper when utilizing heating between aluminum pipe 1 and copper pipe 2, realizes contact reaction brazing.Also can carry out the draw to copper pipe 2 and handle in the back of having pegged graft, and then soldering, to strengthen the closeness of contact of 2 of aluminum pipe 1 and copper pipes.The active bridging agent of no solder of the present invention has the viscosity of appropriateness, and the energy long preservation, can not react with any composition, can weld different metal, nonmetal, the stress that is produced is little, and welding temperature is low, pressure is little, and is less demanding to environment and specimen surface.The active bridging agent of no solder can adopt coating processes such as brushing, spraying, dipping to place on the composition surface of workpiece to be welded.Heating means can adopt methods such as flame heat, eddy-current heating and electric furnace heating.The active nano powder can react at a certain temperature with aluminum pipe and copper pipe, forms a kind of novel alloy between aluminum pipe and copper pipe, and brazing flux can be removed the oxide and the pollutant of aluminum pipe and copper pipe surface when reaching certain heating-up temperature.Quick method for brazing of the present invention is compared with the method for brazing of routine, has realized that the fine and close soldering of aluminium, copper two kinds of materials connects, and the compactness of brazed seam reaches more than 85%, and makes that soldering processes are simplified, the cost reduction.Reduce by 50% with aluminium copper substituting material cost, integrated cost reduces by 35%.

Description of drawings: Fig. 1 is the syndeton schematic diagram of aluminum pipe 1 and copper pipe 2 in the specific embodiment four, Fig. 2 is the syndeton schematic diagram of copper pipe 2 and aluminum pipe 1 in the specific embodiment five, Fig. 3 is the syndeton schematic diagram of copper pipe 2 and aluminum pipe 1 in the specific embodiment six, and Fig. 4 is the syndeton schematic diagram of aluminum pipe 1 and copper pipe 2 in the specific embodiment seven.

The specific embodiment one: the active bridging agent of no solder is made up of active nano powder, non-corrosion type brazing flux, bonding agent composition in the present embodiment, the part by weight relation of these compositions is: bonding agent: non-corrosion type brazing flux: active nano powder=(1～20): (1～2): (0.1～0.4), wherein the purity of active nano powder is 99.90～99.93%, granularity is that 20nm～10 μ m bonding agents are in harmonious proportion and are made by water, organic cellulose, and the weight ratio of water and organic cellulose is 100: (0.5～3).

The specific embodiment two: present embodiment and the specific embodiment one are different is that the purity of active nano powder is 99.93～99.96%, and granularity is 11nm～30 μ m; Each composition part by weight of the active bridging agent of no solder is: bonding agent: non-corrosion type brazing flux: active nano powder=(1～20): (2～4): (0.5～0.8).

The specific embodiment three: present embodiment and the specific embodiment one, two are different is that the purity of active nano powder is 99.96～99.99%, and granularity is 31nm～60 μ m; Each composition part by weight of the active bridging agent of no solder is: bonding agent: non-corrosion type brazing flux: active nano powder=(1～20): (4～5): (0.8～1).

The specific embodiment four: the quick method for brazing of the aluminium of present embodiment, copper insertion pipe is: at first aluminum pipe 1 is processed into outer single conical surface 3-1 with faying face 3 places of the grafting joint of copper pipe 2, and make aluminum pipe 1 at inboard, copper pipe 2 in the outside, spraying the active bridging agent 4 of no solder on the faying face 3, brazing temperature heating routinely then, heating time the P that exerts pressure at the two ends of soldered two pipes, make between aluminum pipe 1 and the copper pipe 2 and in brazing process, remain tight the contact, finish quick brazing process.

The specific embodiment five: present embodiment and the specific embodiment four are different be copper pipe 2 in the inboard, aluminum pipe 1 is in the outside.Other process is identical with the specific embodiment four.

The specific embodiment six: present embodiment and the specific embodiment four are different is that the faying face 3 of joint is processed into bipyramid face 3-2.Other process is identical with the specific embodiment four, five.

The specific embodiment seven: present embodiment and the specific embodiment four are different is in aluminum pipe 1 is inserted in copper pipe 2 time, and the connection-peg of aluminum pipe 1 and copper pipe 2 is not processed the conical surface, the soldering of directly pegging graft.

The specific embodiment eight: the difference of the present embodiment and the specific embodiment seven is also can carry out the draw to copper pipe 2 in the back of having pegged graft to handle, and then soldering.

Claims (10)

1, no brazing material active linking agent, it is characterized in that it comprises following composition: active nanopowder, non-corrosion type brazing flux, bonding agent, the weight ratio relation of each composition is: bonding agent: non-corroding type brazing flux: active Nano powder=(1～20):(1～5):(0～1). 2. The solder-free active connecting agent according to claim 1, characterized in that the purity of the active nano powder is 99.9%-100%, and the particle size is 20nm-100μm. 3. The solder-free active connecting agent according to claim 1, characterized in that the adhesive is prepared by blending water and organic cellulose, and the weight ratio of water to organic cellulose is 100: (0.1-5). 4. The solder-free active connecting agent according to claim 1, characterized in that the purity of the active nano powder is 99.92-99.98%, and the particle size is 20nm-10μm. 5. The preparation method of active linking agent without brazing material, which is characterized in that the active particles with a purity of 99.9% to 100% are mechanically crushed into nano powders with a particle size of 20nm to 100μm; Adhesive, the weight ratio of water and organic cellulose is 100: (0.1 ~ 5), above two kinds of compositions and non-corrosion type flux are mixed by following weight ratio relation, adhesive agent: non-corrosion type flux: active nanometer Powder=(1～5):(1～20):(0～1), making it a solder-free active linking agent. 6. The expansion brazing method of aluminum-copper tubes is characterized in that at first the plug joints of the aluminum tubes (1) and the copper tubes (2) are processed into tapered surfaces (3), and then the solder-free active linking agent (4 ) coated on the brazing surface of the taper surface (3) of the aluminum tube (1) and the copper tube (2) plug joint, and then heated according to the conventional brazing temperature, and pressure is applied to both ends of the two welded tubes during the heating process P, so that the aluminum pipe (1) and the copper pipe (2) are always in close contact during the brazing process, and the rapid brazing process is completed. 7. The expansion brazing method for aluminum-copper tubes according to claim 6, characterized in that the brazing surface (3) of the plug joint between the aluminum tube (1) and the copper tube (2) is processed into an outer single cone surface (3-1), and make the aluminum tube (1) on the outside and the copper tube (2) on the inside. 8. The expansion brazing method for aluminum-copper pipes according to claim 6, characterized in that the brazing surface (3) is processed into a double cone surface (3-2). 9. The expansion brazing method of aluminum-copper tubes according to claim 6, characterized in that when the aluminum tube (1) is inserted into the copper tube (2), the insertion of the aluminum tube (1) and the copper tube (2) The joint does not process the tapered surface and is directly plugged and brazed. 10. The brazing method for aluminum-copper tubes according to claim 9, characterized in that the copper tubes (2) are shrunk after being plugged in, and then brazed.

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