CN102248274A - Sectional heterogeneous material high-temperature solid diffusion/low-temperature transient liquid-phase composite connection method - Google Patents
Sectional heterogeneous material high-temperature solid diffusion/low-temperature transient liquid-phase composite connection method Download PDFInfo
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Abstract
The invention discloses a sectional heterogeneous material high-temperature solid diffusion/low-temperature transient liquid-phase composite connection method. A melting point difference between two heterogeneous materials is 400-800 DEG.C, a metal material with the melting point between the melting points of two base materials is used as an intermediate layer, one end of the intermediate layer is welded with a high-melting point base material by using a solid phase diffusion welding, the welding temperature is higher than the melting point temperature of a low-melting point base material and less than the melting point temperature of the intermediate layer; then the other end of the intermediate layer is connected with the low-melting point base material by using a transient liquid-phase connection technology under a condition that welding temperature is less than the melting point of the low-melting point base material. The heterogeneous materials with obvious differences in physical, chemical and metallurgical property can be connected by using the composite connection method, such as the connection between the metals or the connection between the metal and the non-metal; and in particular, the connection between the heterogeneous materials with melting point difference of 400-800 DEG.C can be realized.
Description
Technical field
The present invention relates to the connection between foreign material, this method of attachment efficiently solves being connected between two foreign materials of physics, chemistry and metallurgical performance significant difference, particularly solved the fusing point difference up between 400 ~ 800 ℃ dissimilar metal or metal and nonmetal 's connectivity problem.
Background technology
Diffusion welding (DW) is meant under process conditions such as certain temperature, pressure, protective medium and keeps a period of time; make the weldment that fits tightly injustice place at the interface produce the micro-plastic deformation and the counterdiffusion of atom phase takes place and form the welding method of connection; usually be also referred to as the solid-state diffusion weldering; manufacturing, the especially connection between foreign material of reactor fuel element, honeycomb panel, current in electrostatic accelerating tube, various blade, impeller, punch die, screen pipe and electronic component etc. have been widely used in.Diffusion welding (DW) requires high to surface quality to be welded, weld interval is longer, the joint quality instability.
It is to add the intermediate layer alloy between by the weldering metal surface that transient liquid phase (being called for short TLP) diffusion connects, rely on the intermediate layer alloy in welding process, takes place fusing or and mother metal between eutectic reaction takes place produces transition liquid-phase and solidify in the process that is incubated, atom diffuses to form a kind of technology that is connected of welding point mutually between intermediate layer and weldment interface.TLP technology combines the advantage of soldering and solid-state diffusion weldering, productivity ratio height, weld interval lack, the strength of joint height, there are not tangible interface and welding residue, by homogenization of composition handle can obtain structural constituent evenly and performance with the close joint of mother metal, wide application prospect in industrial production.
Diffusion welding (DW) is connected with TLP and is used for foreign material and connects and to have unique advantage, has obtained approving widely and using.But in practical application in industry, often having need be to being connected between two foreign materials of physics, chemistry and metallurgical performance significant difference, especially fusing point difference is big owing to the weldment material character, fusing point difference between the dissimilar metal that has even up to 400 ~ 800 ℃, if adopt single diffusion welding (DW) or TLP to connect when connecting between two widely different like this foreign materials, though help spreading in the time of will causing welding temperature high but can cause the fusing or the scaling loss of low melting point mother metal, the bad problem of diffusion between the interface can appear again in welding temperature when low.Therefore at present also powerless to the connection between two foreign materials of significant difference, can only carry out the connection between two less foreign materials of difference.
Summary of the invention
At the prior art above shortcomings, the object of the present invention is to provide a kind of segmented high-temperature solid diffusion/low temperature TLP composite connecting method, this method efficiently solves when utilizing diffusion welding (DW) or TLP weldering that the foreign material of physics, chemistry and metallurgical performance significant difference is connected separately, especially fusing point difference is big owing to the weldment material character, though help spreading when causing welding temperature high but can cause the fusing or the scaling loss of low melting point mother metal, the bad problem of diffusion between the interface can appear again in welding temperature when low.
Technical scheme of the present invention is achieved in that a kind of segmented foreign material high-temperature solid diffusion/low temperature transient liquid phase composite connecting method, fusing point difference between two foreign materials is 400 ~ 800 ℃, fusing point is high relatively is referred to as the high-melting-point mother metal, fusing point is low relatively is referred to as the low melting point mother metal, adopt the metal material of fusing point between two mother metal fusing points as the intermediate layer, its Connection Step is:
1) utilize the solid-state diffusion weldering with intermediate layer one end and the seam of high-melting-point mother metal earlier, welding temperature is higher than low melting point mother metal melting temperature and is lower than the intermediate layer melting temperature;
2) then under the welding temperature condition that is lower than low melting point mother metal fusing point, utilize the transient liquid phase interconnection technique that the intermediate layer other end is connected with the low melting point mother metal, thereby realize connection between two foreign materials by the intermediate layer.
Two foreign materials are metal or a kind of for metal, and another kind is nonmetal, and nonmetal is ceramic.
The described the 1st) Bu welding process is carried out in vacuum or inert gas shielding atmosphere, and in the outer end of intermediate layer and high-melting-point mother metal respectively by pressure head to middle imposed load, this load adopts constant voltage or pulse pressuring method; Be provided with tantalum piece between the pressure head of between the pressure head of high-melting-point mother metal and correspondence and intermediate layer and correspondence, two working faces of tantalum piece respectively are provided with the lubricated oildag of using.
The described the 2nd) Bu connection procedure carries out in vacuum or inert gas shielding atmosphere, and applies the permanent load that size is 0.2 ~ 0.5MPa by potsherd between intermediate layer and low melting point mother metal faying face.
Compared with prior art, the present invention has the following advantages:
1. the present invention can be used for physics, chemistry and the foreign material of metallurgical performance significant difference are connected, and as between dissimilar metal or metal and nonmetal be connected, can realize that especially the fusing point difference reaches the connection between 400 ~ 800 ℃ foreign material.
2. the present invention is guaranteeing between high-melting-point mother metal and intermediate layer can to prevent effectively that the low melting point mother metal from melting in the abundant counterdiffusion mutually of element in welding process.
3. the present invention utilizes high-temperature solid diffusion and the compound interconnection technique of low temperature TLP, is beneficial to promote the joint homogenization of composition and improve bonding strength.
4. technical process of the present invention is simple, and cost is not high, is easy to realize.
In a word, this method is by segmented foreign material high-temperature solid diffusion/low temperature TLP composite connecting method, the advantage of diffusion welding (DW) and two kinds of methods of attachment of TLP weldering is combined, be used for being connected between the foreign material of physics, chemistry and metallurgical performance significant difference, when guaranteeing that high-melting-point mother metal and intermediate layer are fully spread, can prevent from welding process, to melt than the low melting point mother metal, thus the effective connection between the realization weldment.
Description of drawings
Fig. 1-of the present invention phase I-high-melting-point mother metal and intermediate layer high-temperature solid diffusion connection diagram.
Fig. 2-second stage of the present invention-low melting point mother metal is by intermediate layer and high-melting-point mother metal TLP connection diagram.
Fig. 3-phase I high-temperature solid diffusion of the present invention connects (constant voltage) embodiment process schematic representation.
Fig. 4-phase I high-temperature solid diffusion of the present invention connects (pulse pressurization) embodiment process schematic representation.
Wherein, 1-load; The 2-pressure head; The 3-oildag; The 4-tantalum piece; 5-high-melting-point mother metal; The 6-intermediate layer; The 7-permanent load; The 8-potsherd; 9-low melting point mother metal.
The specific embodiment
Thinking of the present invention is: the fusing point difference between two foreign materials is 400 ~ 800 ℃, fusing point is high relatively is referred to as the high-melting-point mother metal, fusing point is low relatively is referred to as the low melting point mother metal, adopt the metal material of fusing point between two mother metal fusing points as the intermediate layer, take two step methods of attachment pointedly, when guaranteeing that high-melting-point mother metal and intermediate layer are fully spread, prevent that the low melting point mother metal from melting in welding process: utilize high-temperature solid diffusion connection that intermediate layer and high-melting-point mother metal are carried out the high-temperature solid diffusion earlier and be connected (High-Temperature Solid-State Diffusion Bonding), according to diffusion equation, the elemental diffusion coefficient can be the index raising along with temperature raises, just can guarantee that by the high-temperature solid diffusion connecting process counterdiffusion mutually fully takes place element between high-melting-point mother metal and intermediate layer, form excellent metallurgical and engage; Then under the welding temperature condition that is lower than low melting point mother metal fusing point, utilize low temperature transient liquid phase interconnection technique (Low-Temperature Transient Liquid-Phase (TLP) Bonding), between low melting point mother metal and intermediate layer, produce a certain amount of liquid phase and realize the seam in low melting point mother metal and intermediate layer, TLP connects the quality requirement that technology can reduce the welding surface preparation, reduce weld interval and improve the stability of joint quality, thereby finally realize the effective connection between weldment.
Its specific implementation process is:
1) phase I-utilize solid-state diffusion weldering with intermediate layer 6 one ends and 5 seam of high-melting-point mother metal earlier, welding temperature is higher than low melting point mother metal melting temperature and is lower than the intermediate layer melting temperature, as shown in Figure 1.Can promote the abundant counterdiffusion mutually of element between high-melting-point mother metal and intermediate layer implement connecting under the higher welding temperature condition.For guaranteeing that connecting technical process implements, the welding process in this step is carried out in vacuum or inert gas shielding atmosphere, and respectively passes through pressure head 2 to middle imposed load 1 in the outer end of intermediate layer and high-melting-point mother metal, and this load adopts constant voltage or pulse pressuring method.Be provided with tantalum piece 4 between between high-melting-point mother metal 5 and the corresponding pressure head 2 and intermediate layer 6 and the corresponding pressure head 2 and directly contact with pressure head, respectively be provided with between two working faces of tantalum piece 4 and corresponding bonded block and lubricate usefulness oildag 3 to prevent material to be welded.
2) second stage-low melting point mother metal 9 carries out low temperature TLP by intermediate layer 6 with high-melting-point mother metal 5 and is connected.Connection procedure carries out under the condition that is lower than low melting point mother metal melting temperature, can prevent that the low melting point mother metal from melting in welding process.Utilize low temperature transient liquid phase interconnection technique, between low melting point mother metal 9 and intermediate layer 6, produce a certain amount of liquid phase, but liquid metal blind makes also some element in the liquid phase spread to mother metal, form metallurgical binding at last, realize that low melting point mother metal 9 is connected with the effective of high-melting-point mother metal 5.This step is carried out in vacuum or inert gas shielding atmosphere equally, and applies the permanent load 7 that size is 0.2 ~ 0.5MPa by potsherd 8 between intermediate layer 6 and low melting point mother metal 9 faying faces, sees Fig. 2.Potsherd 8 directly contacts with the device that applies faint load with objective table in order to prevent material to be welded.
The present invention can be used for realizing that the fusing point difference is between 400 ~ 800 ℃ dissimilar metal or metal and nonmetal be connected, and utilizes high-temperature solid diffusion and the compound interconnection technique of low temperature TLP, is beneficial to promote joint homogenization of composition and raising bonding strength.Employed solid-state diffusion weldering of phase I of the present invention there is no essential different with the TLP welding method that second stage is used with conventional solid-state diffusion weldering and TLP method of attachment.
Below provide two specific embodiments to help the understanding of the present invention.
Embodiment 1: utilizing segmented high-temperature solid diffusion/low temperature TLP composite connecting method is that the Copper Foil of 150 μ m is AZ31B magnesium alloy and the 304L stainless steel dissimilar material of 16mm as the intermediate layer weld diameter with thickness.Technological parameter is: the high-temperature solid diffusion phase: temperature is 850 ° of C, and impulse load is 5 ~ 20MPa, and the time is 20 minutes; The low temperature TLP stage: temperature is 495 ° of C, and plus load is 0.2MPa, and the time is 10 minutes.Micro-analysis is the result show, realized effective connection.
Embodiment 2: utilizing segmented high-temperature solid diffusion/low temperature TLP composite connecting method is that the Copper Foil of 150 μ m is 5083 aluminium alloys and the 304L stainless steel dissimilar material of 16mm as the intermediate layer weld diameter with thickness.Technological parameter is: the high-temperature solid diffusion phase: temperature is 850 ° of C, and impulse load is 5 ~ 20MPa, and the time is 20 minutes; The low temperature TLP stage: temperature is 555 ° of C, and plus load is 0.2MPa, and the time is 5 minutes.Micro-analysis is the result show, realized effective connection.
Embodiment 3: utilize TA17 titanium alloy and the 0Cr18Ni9Ti stainless steel dissimilar material of permanent load high-temperature solid diffusion method of attachment weld diameter for 16mm.The technological parameter of phase I is: temperature is 850 ° of C, and permanent load is 5MPa, and temperature retention time is 10 minutes; Programming rate and cooling rate are 5 ° of C/s, see Fig. 3.Micro-analysis is the result show, realized effective connection.
Embodiment 4: utilize TA17 titanium alloy and the 0Cr18Ni9Ti stainless steel dissimilar material of impulse load high-temperature solid diffusion method of attachment weld diameter for 16mm.The technological parameter of phase I is: temperature is 850 ° of C, and impulse load is 5 ~ 20MPa, and pulse frequency is 0.5Hz, and pulse number is 300 times, and temperature retention time is 10 minutes; Programming rate and cooling rate are 5 ° of C/s, see Fig. 4.Micro-analysis is the result show, realized effective connection.
Claims (4)
1. segmented foreign material high-temperature solid diffusion/low temperature transient liquid phase composite connecting method, it is characterized in that: the fusing point difference between two foreign materials is 400～800 ℃, fusing point is high relatively is referred to as the high-melting-point mother metal, fusing point is low relatively is referred to as the low melting point mother metal, adopt the metal material of fusing point between two mother metal fusing points as the intermediate layer, its Connection Step is:
1) utilize the solid-state diffusion weldering with intermediate layer one end and the seam of high-melting-point mother metal earlier, welding temperature is higher than low melting point mother metal melting temperature and is lower than the intermediate layer melting temperature;
2) then under the welding temperature condition that is lower than low melting point mother metal fusing point, utilize the transient liquid phase interconnection technique that the intermediate layer other end is connected with the low melting point mother metal, thereby realize connection between two foreign materials by the intermediate layer.
2. segmented high-temperature solid diffusion/low temperature transient liquid phase composite connecting method according to claim 1 is characterized in that: two foreign materials are metal or a kind of for metal, and another kind is nonmetal, and nonmetal is ceramic.
3. segmented high-temperature solid diffusion/low temperature transient liquid phase composite connecting method according to claim 1 and 2, it is characterized in that: the described the 1st) Bu welding process is carried out in vacuum or inert gas shielding atmosphere, and in the outer end of intermediate layer and high-melting-point mother metal respectively by pressure head to middle imposed load, this load adopts constant voltage or pulse pressuring method; Be provided with tantalum piece between the pressure head of between the pressure head of high-melting-point mother metal and correspondence and intermediate layer and correspondence, two working faces of tantalum piece respectively are provided with the lubricated oildag of using.
4. segmented high-temperature solid diffusion/low temperature transient liquid phase composite connecting method according to claim 3; it is characterized in that: the described the 2nd) Bu connection procedure carries out in vacuum or inert gas shielding atmosphere, and applies the permanent load that size is 0.2～0.5MPa by potsherd between intermediate layer and low melting point mother metal faying face.
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Cited By (4)
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| CN106475679A (en) * | 2016-11-30 | 2017-03-08 | 山东大学 | A kind of copper and the discontinuous pressure process diffusion connecting process of the unrepeatered transmission of aluminium alloy |
| CN110508957A (en) * | 2019-09-09 | 2019-11-29 | 南昌航空大学 | A kind of soldering of double panel structure/stepped combined connection method of instant liquid diffusion welding (DW) |
| CN115323200A (en) * | 2022-07-21 | 2022-11-11 | 惠州德晋昌光电科技有限公司 | Solid-liquid diffusion method of mixture, alloy material, and preparation method and application of alloy material |
| CN116689932A (en) * | 2023-08-02 | 2023-09-05 | 杭州沈氏节能科技股份有限公司 | Diffusion welding method of micro-channel heat exchanger and welded product |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN116689932A (en) * | 2023-08-02 | 2023-09-05 | 杭州沈氏节能科技股份有限公司 | Diffusion welding method of micro-channel heat exchanger and welded product |
| CN116689932B (en) * | 2023-08-02 | 2023-10-31 | 杭州沈氏节能科技股份有限公司 | Diffusion welding method of micro-channel heat exchanger and welded product |
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