CN105659724B - A kind of method and fixture of dissimilar metal salt bath Diffusion Welding - Google Patents
A kind of method and fixture of dissimilar metal salt bath Diffusion WeldingInfo
- Publication number
- CN105659724B CN105659724B CN200610119879.7A CN200610119879A CN105659724B CN 105659724 B CN105659724 B CN 105659724B CN 200610119879 A CN200610119879 A CN 200610119879A CN 105659724 B CN105659724 B CN 105659724B
- Authority
- CN
- China
- Prior art keywords
- salt bath
- welding
- fixture
- diffusion welding
- dissimilar metal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Links
- 238000003466 welding Methods 0.000 title claims abstract description 62
- 238000009792 diffusion process Methods 0.000 title claims abstract description 42
- 239000011780 sodium chloride Substances 0.000 title claims abstract description 38
- 150000003839 salts Chemical class 0.000 title claims abstract description 35
- 239000002184 metal Substances 0.000 title claims abstract description 14
- 229910052751 metal Inorganic materials 0.000 title claims abstract description 14
- PXHVJJICTQNCMI-UHFFFAOYSA-N nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims abstract description 37
- 229910052759 nickel Inorganic materials 0.000 claims abstract description 18
- 238000000034 method Methods 0.000 claims abstract description 17
- 238000010791 quenching Methods 0.000 claims abstract description 9
- 239000011888 foil Substances 0.000 claims abstract description 8
- 238000010438 heat treatment Methods 0.000 claims abstract description 7
- 238000001816 cooling Methods 0.000 claims abstract description 5
- 238000009413 insulation Methods 0.000 claims abstract description 4
- 238000010030 laminating Methods 0.000 claims abstract description 4
- 238000007747 plating Methods 0.000 claims abstract description 4
- 238000010792 warming Methods 0.000 claims abstract description 4
- 239000007769 metal material Substances 0.000 claims abstract description 3
- 239000000463 material Substances 0.000 claims description 20
- WCUXLLCKKVVCTQ-UHFFFAOYSA-M potassium chloride Chemical compound [Cl-].[K+] WCUXLLCKKVVCTQ-UHFFFAOYSA-M 0.000 claims description 6
- FAPWRFPIFSIZLT-UHFFFAOYSA-M sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 claims description 6
- 239000000203 mixture Substances 0.000 claims description 4
- 229910052718 tin Inorganic materials 0.000 abstract description 15
- ATJFFYVFTNAWJD-UHFFFAOYSA-N tin hydride Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 abstract description 15
- 229910000906 Bronze Inorganic materials 0.000 abstract description 14
- 239000010974 bronze Substances 0.000 abstract description 14
- 229910000746 Structural steel Inorganic materials 0.000 abstract description 13
- 238000004519 manufacturing process Methods 0.000 abstract description 5
- 229910000679 solder Inorganic materials 0.000 abstract description 3
- 238000005516 engineering process Methods 0.000 description 7
- 238000006073 displacement reaction Methods 0.000 description 6
- 239000000243 solution Substances 0.000 description 6
- 230000000171 quenching Effects 0.000 description 5
- 229920003023 plastic Polymers 0.000 description 4
- 229910052802 copper Inorganic materials 0.000 description 3
- 229920000426 Microplastic Polymers 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- 125000004429 atoms Chemical group 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000012071 phase Substances 0.000 description 2
- 238000005476 soldering Methods 0.000 description 2
- 239000006104 solid solution Substances 0.000 description 2
- 206010011376 Crepitations Diseases 0.000 description 1
- 229910018054 Ni-Cu Inorganic materials 0.000 description 1
- 229910018481 Ni—Cu Inorganic materials 0.000 description 1
- 235000008331 Pinus X rigitaeda Nutrition 0.000 description 1
- 235000011613 Pinus brutia Nutrition 0.000 description 1
- 241000018646 Pinus brutia Species 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 239000003082 abrasive agent Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- REDXJYDRNCIFBQ-UHFFFAOYSA-N aluminium(3+) Chemical class [Al+3] REDXJYDRNCIFBQ-UHFFFAOYSA-N 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 230000000977 initiatory Effects 0.000 description 1
- 229910000765 intermetallic Inorganic materials 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000003350 kerosene Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 238000003032 molecular docking Methods 0.000 description 1
- 230000002085 persistent Effects 0.000 description 1
- 238000010008 shearing Methods 0.000 description 1
- 230000000087 stabilizing Effects 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
Abstract
The present invention is a kind of method and fixture of dissimilar metal salt bath Diffusion Welding, and processing step the following is: (1) calculates welding pressure required between tin bronze and structural steel; (2) between the faying face that tin bronze and structural steel need to weld using nickel foil or on a kind of metal material nickel plating as intermediate layer, (3) the faying face laminating clamping that above-mentioned tin bronze and structural steel need to weld by special fixture is adopted, (4) tin bronze after packing clamp into and structural steel workpiece are put into salt bath heating stove, its welding and thermal process system are as follows: the first stage: workpiece is warming up to 860 ~ 880 DEG C with stove, insulation 30min, carries out diffusion welding (DW); Second stage: quench, oil cooling. Adopt the slippery boots assembly of above-mentioned explained hereafter successfully to realize production domesticization, solder yield can reach more than 85%, meets the indices requirement that product uses.<pb pnum="1" />
Description
Technical field
The present invention is a kind of method and fixture of dissimilar metal salt bath Diffusion Welding, belongs to solder technologyField.
Background technology
Salt bath Diffusion Welding is a kind of process of special, solid-state connection, and it is to protect at salt bathProtecting under state utilizes certain temperature and pressure that part welding surface is contacted with each other, and is moulded by microcosmicProperty is out of shape and makes welding surface produce micro-liquid phase and expand the physical contact of face of weld, thenA kind of welding method of metallurgical binding is realized through the atom phase counterdiffusion of long period. This diffusionThe advantage of method of attachment maximum be weld region without defects such as cast sturcture, brittle zone, crackles,Do not generate the low melting point district as soldering.
In the precision friction submember of high performance turbine product, adopt high-abrasive material and structure in a large numberThe friction pair that Material constitution coefficient of friction is little, performance good, the life-span is long, as Soviet Union-27, meter Ge-29,Various plunger displacement pumps in the aircrafts such as F-16. At China WS10 engine plunger displacement pump and Soviet Union-27 engineIn plunger displacement pump overhaul, also use the friction pair member of wear-resisting tin bronze and structural steel composition, whereinWear-resisting tin bronze requires to adopt diffusion welding (DW) to be connected with structural steel. Because diffusion welding craft comes from Russia,As an important know-how, foreign side is very tight to the control of this technology, cannot obtainRelated data, can only rely on domestic tackling key problem.
Before using salt bath Diffusion Welding, adopt the method for vacuum diffusion welding, but vacuum diffusion weldingUnder at present domestic condition, have some technical problems to be solved all the time at all, its mainly:
1. diffusion in vacuum soldering equipment does not possess the gas function of quenching, and part postwelding is annealed condition, Bu NengmanThe requirement of centre hardness, case hardness and the pulling-out force of foot steelwork, needs again before part processingHeating quenching easily causes weld cracking in quenching process;
2. technology stability is subject to the impact of season, equipment etc. comparatively large, and percent defective and welding cost are all veryHeight, the production cycle very long (every stove needs a whole day), production efficiency is very restricted. Along with lifeThe expanding day of product demand, wishes that a kind of suitable technology generations is for diffusion in vacuum Welding.
In order to solve above-mentioned Problems existing, the method for salt bath Diffusion Welding need to be developed.
Summary of the invention
The present invention designs provide for above-mentioned domestic existing technology status and existing problems justMethod and the fixture of dissimilar metal salt bath Diffusion Welding, its objective is and adopt ordinary salt liquid furnace to enterRow Diffusion Welding, reaches process stabilizing, reliable in quality, high, the lower-cost technique of production efficiencyEffect.
The object of the invention is to be realized by following technological measure:
The method of dissimilar metal salt bath Diffusion Welding of the present invention, is characterized in that: the methodStep be:
(1) the faying face laminating clamping that dissimilar metal need to weld by fixture is used, institute's applied pressureCalculate by the lower material of yield strength, its computing formula is:
Qmax＝[σ]×A
Wherein: Qmax is the maximum positive voltage power applying, A is that face of weld is long-pending
[σ] is allowable stress [σ] < σ0.2σ0.2For the yield strength of this kind of material
Pressure selection and the vacuum diffusion welding of salt bath diffusion welding (DW) are very different. Vacuum diffusion weldingPressure parameter is set by technological requirement before weldering, and in whole welding process thereafter, pressure is constantBecome or regulate and control on demand, this persistent pressure mode does not need disposable (before weldering) to existWorkpiece imposes severe pressure (4MPa ~ 10MPa can meet diffusion welding (DW) needs conventionally), from welderingConnect in principle and say, under vacuum diffusion welding process conditions, face of weld produces micro-plastic deformation and isIn heating process, progressively realize.
Salt bath diffusion welding (DW) is that fixture is put into salt bath, therefore can only before weldering the disposable pressure that applies,Consider that the fastening bolt of fixture, under continuous high temperature, plastic deformation and high-temerature creep can occur, causeThe phenomenon of the lax reduction of pressure, requires the thrust of once exerting pressure that the compression of vacuum diffusion welding should be greater thanPower, can ensure that the face of weld of workpiece in the starting stage of solid-state and high temperature, namely atom occurs and expandsLoose required micro-plastic deformation.
For salt bath diffusion welding (DW), how to determine that welding pressure is a blank in theory, do not haveAny data can be for reference, has according to material expansion coefficient calculations pressure in diffusion in vacuum WeldingViewpoint, but the obvious inapplicable salt bath diffusion welding craft of this viewpoint, when conceptual design, thisBright technical scheme proposes the yield strength (σ according to material0.2) set the thinking of welding pressure, bothWelding pressure produces the strength degree of plastic deformation as critical value taking material, determines upper pressure limit. ?The occasion of dissimilar metal diffusion welding (DW), welding pressure is by yield strength (σ0.2) lower material calculates,This is set as to upper pressure limit, and rated pressure should not be greater than the yield strength (σ of alloy0.2), otherwiseEasily there is macroscopical plastic deformation, cause the faults in material such as intergranular micro-crack.
(2) workpiece of clamping is put into salt bath furnace, salt bath composition is by weight percentage: 50%NaCl, 50% KCl, its welding and heat treatment process system is as follows:
First stage: workpiece is warming up to 860 ~ 880 DEG C with stove, insulation 25 ~ 30min;
Second stage: quench, oil cooling.
Improve diffusion welding (DW) temperature to 860 ~ 880 DEG C, be improve strength of joint the most directly, the most effectiveWay, but too high welding temperature can make the rear much higher hard of steelwork quenching, affects following process,For solving this contradiction, technical solution of the present invention proposes mentality of designing and the method in intermediate layer.
The use in intermediate layer, the welding for foreign material has multiple special effect. Xenogenesis materialMaterial is due to the difference of thermal coefficient of expansion, in cooling procedure, and the docking area of weldment can produce remainingStress, coefficient of expansion difference is larger, and residual stress is also larger, and adopts the coefficient of expansion between two kindsBetween material or the material of high-ductility as intermediate layer, the stress of generation can be made to be relaxed. ?In Diffusion Welding, use intermediate layer that part real contact area can also be increased, accelerate the shape of metallic bondBecome and enhanced dispersion process.
According to above-mentioned mentality of designing, technical solution of the present invention is before above-mentioned steps (1), at xenogenesis goldBelong to need welding faying face between using nickel foil or on a kind of metal material nickel plating as intermediate layer,Wherein, the thickness of nickel foil is: 8 ~ 25 μm, and the thickness of nickel coating is: 13 ~ 20 μm.
Between material, form intermetallic compound and brittlement phase, require intermediate layer and two kindsMaterial can form solid solution, and intermediate layer material is greater than to the diffusion velocity that is diffused materialBe diffused the diffusion velocity of material to intermediate layer.
Weld jig is to ensureing that welding quality has very important effect, and this is salt bath diffusion welding (DW)Operational characteristic determines. In welding process, guarantee that face of weld fits tightly fixture will be leaned on completelyEffect, slightly changes a series of weld defect such as seam will be caused bad.
With respect to vacuum diffusion welding, salt bath diffusion welding (DW) is higher to the requirement of jig Design, and this on the one handThat service condition due to fixture is very severe, as the heat treatment repeatedly of high-temperature salt bath burn into, repeatedlyDismounting, causes reduce service life, on the other hand, because welding pressure is large and Repeat quenching, and folderThe deformation extent of tool is large, needs often processing finishing and standard of replacement part to maintain the precision of fixture,Therefore, jig Design must be considered above feature, instructions for use should be met, have againEconomy preferably.
According to above-mentioned technical requirement, the fixture that is applicable to technical solution of the present invention is designed to tubular,Be processed with through hole along axis, the two ends of through hole are by screw thread setting pressure nut, the top of pressure nutEnd is pressure head, and welding work pieces is arranged between two pressure heads, on the fixture sidewall at location of workpiece placeBe added with salt discharge orifice.
The fixture of this kind of structure improves the force-bearing situation of workpiece, screwing force pine when also improve high temperatureThe phenomenon of speeding, in addition, it is simple to operate, high life, good reliability and processing cost also thanLower.
Accompanying drawing explanation
Fig. 1 is the structural representation of the fixture described in technical solution of the present invention
Detailed description of the invention
Below with reference to drawings and Examples, technical solution of the present invention is further described:
China WS10 engine plunger displacement pump (RZB10A) and Soviet Union's-27 engine plunger displacement pumps (H ∏ 96M)In overhaul, also use friction pair member, piston shoes and the swash plate of wear-resisting tin bronze and structural steel compositionThis is more than 300 kilograms to pair of friction components contact force, and piston shoes are subject to spin friction, shearing and impact. SlidingBoots are worked under high-voltage high-speed, and working media is kerosene, and condition of work is more severe. Wherein wear-resisting tinBronze requires to adopt salt bath diffusion welding (DW) to be connected with structural steel. Requirement is that joint tensile strength is greater than150Mpa。
Adopt the concrete technology step of technical solution of the present invention as follows:
(1) welding pressure required between tin bronze and structural steel is calculated:
Welding pressure calculates by the lower material of yield strength (σ 0.2), according to this thinking, rightThe welding pressure of ZCuSn10Pb2Ni3 tin bronze calculates, bending of ZCuSn10Pb2Ni3 tin bronzeTake intensity (σ 0.2) for 182.28MPa, this is set as to upper pressure limit, and rated pressure should be not largeIn the yield strength (σ 0.2) of alloy, otherwise easily there is macroscopical plastic deformation, initiation intergranular fine fisssureThe faults in material such as line,
Computational process is as follows:
The yield strength σ 0.2=182.28MPa of tin bronze
Allowable stress [σ] choosing value is: [σ] < σ 0.2=121.5MPa
The maximum pressure that can apply:
Qmax＝[σ]×A＝121.5×3.14×20.32÷4＝39.3KN
A is that face of weld is long-pending
(2) between the faying face that tin bronze and structural steel need to weld with nickel foil or at a kind of metalOn material, nickel plating is as intermediate layer,
When adopting nickel foil material, the thickness of nickel foil is chosen as: 8 ~ 25 μm, be covered in needsThe faying face of welding;
Adopt during nickel coating, by nickel metal-plated on the surface that structural steel need to weld, nickel coatingThickness is 13 ~ 20 μm.
Do intermediate layer with Ni, according to the equilibrium state diagram of Fe-Ni-Cu, Ni and Fe and Cu all canForm unlimited continuous solid solution, Ni can improve Fe dissolving in Fe at Cu and Cu greatly simultaneouslyDegree, these features have very large benefit concerning dissimilar metal diffusion welding (DW).
(3) see shown in accompanying drawing 1, adopt this kind of fixture that above-mentioned tin bronze and structural steel are needed to weldingFaying face laminating clamping, this fixture 1 is tubular, is processed with through hole, the two ends of through hole along axisBy screw thread setting pressure nut 3, the top of pressure nut 3 is pressure head 4, by tin bronze and structureWelding work pieces 5 after the faying face that steel need to weld fits together is arranged between two pressure heads 4,Fixture 1 sidewall of workpiece 5 position is added with salt discharge orifice 2. By screwing two pressure nuts 3Pressure head 4 is pressurizeed to workpiece 5, and pressurization size is determined by calculated value above. The work of salt discharge orifice 2With being in welding process, fused salt can directly be heated welding position by it.
(4) tin bronze after packing clamp into and structural steel workpiece are put into salt bath heating stove, typeNumber be RDMZS-6-9, salt bath composition is by weight percentage: 50% NaCl, 50% KCl, itsWelding and heat treatment process system is as follows:
First stage: workpiece is warming up to 880 DEG C with stove, insulation 30min, carries out diffusion welding (DW);
Second stage: quench, oil cooling.
Adopt the slippery boots assembly of above-mentioned explained hereafter in a large number for H ∏ 96M overhaul (300 component parts for assembly of a machine portionsDivide and change part) and assembling RZB10A plunger displacement pump (30), successfully realizing production domesticization, is piston shoes groupSalt bath diffusion welding craft route, technological parameter, examination requirements that part is formulated are correct, feasible,Technical process is basicly stable, can meet design requirement by the slippery boots assembly of current technology scheme welding,Solder yield can reach more than 85%.
Claims (3)
1. a method for dissimilar metal salt bath Diffusion Welding, is characterized in that: the step of the methodFor:
(1) the faying face laminating clamping that dissimilar metal need to weld by fixture is used, institute's applied pressureCalculate by the lower material of yield strength, its computing formula is:
Qmax＝[σ]×A
Wherein: Qmax is the maximum positive voltage power applying, A is that face of weld is long-pending
[σ] is allowable stress [σ] < σ0.2σ0.2For the yield strength of this kind of material
(2) workpiece of clamping is put into salt bath furnace, salt bath composition is by weight percentage: 50%NaCl, 50% KCl, its welding system of heat treatment process is as follows:
First stage: workpiece is warming up to 860 ~ 880 DEG C with stove, insulation 25 ~ 30min;
Second stage: quench, oil cooling.
2. the method for dissimilar metal salt bath Diffusion Welding according to claim 1, its feature existsIn: before above-mentioned steps (1), between the faying face that dissimilar metal need to weld with nickel foil orOn a kind of metal material, nickel plating as intermediate layer, wherein, and the thickness of nickel foil is: 8 ~ 25 μm, platingThe thickness of nickel dam is: 13 ~ 20 μm.
3. the method for the dissimilar metal salt bath Diffusion Welding described in the claims 1Fixture, is characterized in that: this fixture (1) is tubular, is processed with through hole, the two ends of through hole along axisBy screw thread setting pressure nut (3), the top of pressure nut (3) is pressure head (4), and workpiece (5) is establishedPut between two pressure heads (4), fixture (1) sidewall of workpiece (5) position is added with salt discharge orifice(2)。
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN105659724B true CN105659724B (en) | 2011-04-27 |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106271033A (en) * | 2016-08-28 | 2017-01-04 | 中航力源液压股份有限公司 | A kind of tin bronze and the diffusion welding method of steel welding construction |
| CN107214411A (en) * | 2017-07-07 | 2017-09-29 | 中国科学院工程热物理研究所 | Printed circuit board Welding of Heat-exchanger system and method |
| CN113042876A (en) * | 2021-04-01 | 2021-06-29 | 东北大学秦皇岛分校 | Friction stir material increase manufacturing method with preset heterogeneous metal interlayer |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106271033A (en) * | 2016-08-28 | 2017-01-04 | 中航力源液压股份有限公司 | A kind of tin bronze and the diffusion welding method of steel welding construction |
| CN106271033B (en) * | 2016-08-28 | 2019-01-08 | 中航力源液压股份有限公司 | A kind of diffusion welding method of tin bronze and steel welding construction |
| CN107214411A (en) * | 2017-07-07 | 2017-09-29 | 中国科学院工程热物理研究所 | Printed circuit board Welding of Heat-exchanger system and method |
| CN107214411B (en) * | 2017-07-07 | 2019-09-24 | 衡水中科衡发动力装备有限公司 | Printed circuit board Welding of Heat-exchanger system and method |
| CN113042876A (en) * | 2021-04-01 | 2021-06-29 | 东北大学秦皇岛分校 | Friction stir material increase manufacturing method with preset heterogeneous metal interlayer |
| CN113042876B (en) * | 2021-04-01 | 2023-04-21 | 东北大学秦皇岛分校 | Friction stir additive manufacturing method for presetting heterogeneous metal interlayer |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR03 | Grant of secret patent right | ||
| DC01 | Secret patent status has been lifted | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20110427 Termination date: 20180926 |