CN107717156B - A kind of unimach and tungsten alloy inner hole method for welding - Google Patents
A kind of unimach and tungsten alloy inner hole method for welding Download PDFInfo
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- CN107717156B CN107717156B CN201710930175.6A CN201710930175A CN107717156B CN 107717156 B CN107717156 B CN 107717156B CN 201710930175 A CN201710930175 A CN 201710930175A CN 107717156 B CN107717156 B CN 107717156B
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- shell
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- welding
- unimach
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Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K1/00—Soldering, e.g. brazing, or unsoldering
- B23K1/008—Soldering within a furnace
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K1/00—Soldering, e.g. brazing, or unsoldering
- B23K1/20—Preliminary treatment of work or areas to be soldered, e.g. in respect of a galvanic coating
- B23K1/203—Fluxing, i.e. applying flux onto surfaces
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K1/00—Soldering, e.g. brazing, or unsoldering
- B23K1/20—Preliminary treatment of work or areas to be soldered, e.g. in respect of a galvanic coating
- B23K1/206—Cleaning
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/18—Hardening; Quenching with or without subsequent tempering
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/26—Methods of annealing
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/0068—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for particular articles not mentioned below
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K2103/00—Materials to be soldered, welded or cut
- B23K2103/18—Dissimilar materials
Abstract
The invention discloses the inner hole method for welding of a kind of unimach and tungsten alloy, including cutting solder piece, the solder piece is fixed on liner outer surface, allow liner to be wrapped up the shell that will be filled with solder piece to be placed in shell inner hole by solder piece and liner assembly is put into soldering oven, setting soldering furnace temperature is more than solder piece melting point, continuous heating is for a period of time, solder piece sufficiently melts, and solder is sufficient filling with the gap between liner and case weld face, completes normalizing procedure；Annealing processing is carried out to the shell and liner assembly that are filled with solder；Soldering furnace temperature is increased to brazing filler metal melts, unimach and tungsten alloy weldment are quenched.The method of technical solution of the present invention combines high temperature brazing, quenching, tempering, combines dissimilar material soldering processes sufficiently with case material heat treatment process, obtains high-intensitive high welded rate soldered fitting while guaranteeing shell high-strength tenacity.
Description
Technical field
The invention belongs to welding manufacture technology fields, and in particular to a kind of unimach and tungsten alloy inner hole are brazed
Method.
Background technique
Soldering tech is a kind of technical process for melting solder heat, connecting two or several metal parts；
It uses the solder lower than base material temperature, and base material links together after fusing.By heating, liquid solder is in the gap of base material
Middle wetting capillary flow, is filled, is sprawled, interacting with base material, in above process, the solder of thawing and base metals it
Between dissolution, diffusion or generate intermetallic compound, firm connector is formed after condensation, so that base material be linked together.Soldering
Small, connector smooth and beautiful appearance is deformed, accurate welding, complexity and the component being made of different materials are suitable for, such as honeycomb panel, thoroughly
Flat blade, hard alloy cutter and printed circuit board etc..
Currently, the wide dissimilar metal connection combination of domestic application has: aluminium and aluminium alloy and copper, aluminium and aluminium alloy and copper
Or stainless steel, aluminium and aluminium alloy and titanium alloy, carbon steel and low-alloy steel and high temperature alloy, ceramics and ceramics and common metal etc.,
And for the vacuum brazing of unimach and tungsten alloy since its technical difficulty is excessively high, it there is no mature technical solution at present.
After unimach, which combines soldering with tungsten alloy, to be integrally formed, integration of the tungsten alloy in unimach inner hole is formd
Sub-assembly, this sub-assembly have good hot property and mechanical property；Due to the metallicity of unimach and tungsten alloy
It differs greatly, two kinds of materials, which are neither able to achieve to dissolve each other, is also not easy to be formed intermetallic compound, and current technology scheme is difficult to reach
The requirement of its soldering tech, therefore need to seek a kind of scheme that can solve unimach and combine brazing problems with tungsten alloy.
In common dissimilar material brazing process, the brazing filler metal fusing point of selection is generally less than base material, the fusing point between base material
Difference will not be very big, could keep as far as possible the shape of base material when melting solder in this way.Meanwhile the weldering between base material
Junction is generally exposed, and welding gap can adjust at any time, and welding operating space is big outside, and solder can successfully uniformly after melting
It is filled between welding surface, it is not easy to form welding bubble.After brazing filler metal melts in the gap of base material Uniform Flow, while solder
Atom interpenetrates interaction between the atom on base material welding surface surface layer at high temperature, is fixedly connected on base material after cooling
Together.But fusing point, thermal expansion coefficient, specific heat capacity and the elasticity modulus of unimach and both tungsten alloys are with biggish
Difference, if the fusing point of unimach is 1530 DEG C, the fusing point of tungsten alloy has then reached 3380 DEG C.When being brazed,
Good infiltration relationship cannot be formed if the fusing point of solder is too low, between solder and tungsten alloy, be difficult to reach solid after cooling
Determine the bond strength of unimach and tungsten alloy；If the fusing point of selection solder is excessively high, be warming up to that solder is in a liquid state when
It waits, it is possible to which the coarse grains even tissue overheating that will lead to base material unimach causes degraded toughness.Some more special
Different welding demand, if welding surface is inner hole, in the case where especially deep blind hole curved surface, welding surface is hidden in welding base metal
Portion causes the position between shell and liner to be difficult to determine, welding the size between gap is even more to have stringent size requirement.
Weld seam is excessive, then the solder for needing to fill is excessive, it is difficult to form effective metallic atom infiltration in commissure, welding quality is low；
Weld seam is too small, then the solder melted, which is difficult to uniformly be filled between welding surface, forms effective welding surface, and weld seam easy to form
Bubble influences welding position intensity.In fact, shell and liner weld interface are deep blind hole curved surface, it is to be most disadvantageous in welding
Structure.The gap between shell and liner is how controlled, the throat thickness of solder, and the control to solder temperature are adjusted,
It is all a problem to be solved, existing welding technique is also difficult to ensure the intensity of unimach Yu tungsten alloy soldered fitting.
Summary of the invention
Aiming at the above defects or improvement requirements of the prior art, the present invention provides in a kind of unimach and tungsten alloy
Hole method for welding.The method of technical solution of the present invention is difficult to meet unimach and tungsten alloy for soldering in the prior art
Welding demand the case where, using with the preferable solder of the matching degree of unimach heat treatment parameter, and after the completion of soldering
Shell is quenched and is tempered；By soldering and heat treatment process Application of composite, superhigh intensity can have effectively been solved just and tungsten
Welding Problems between alloy.
To achieve the above object, according to one aspect of the present invention, the interior of a kind of unimach and tungsten alloy is provided
Hole method for welding, is welded in shell inner hole for realizing by liner, which is characterized in that including
S1 uniformly coats solder on the welding surface of liner, the liner for being coated with solder is placed in shell inner hole, so that pricker
Material is uniformly laid between shell and the welding surface of liner；
S2 heating is filled with the shell and liner of solder piece, and heating temperature is arranged more than solder piece melting point；Persistently plus
Heat to solder piece sufficiently melts, and solder is sufficient filling with the gap between liner and case weld face；
S3 anneals to the shell and liner weldment that handle through step S2；
S4 improves heating temperature to brazing filler metal melts, quenches the shell and liner weldment that handle through step S3
Fire, to realize that the inner hole of unimach and tungsten alloy is brazed.
The inner hole method for welding of technical solution of the present invention, mainly between the biggish two kinds of base materials of physical property gap into
The soldering of row inner hole.The base material for offering inner hole to be welded is shell, and the base material being soldered in inner hole is liner.Wherein, shell
On inner hole can be through-hole, be also possible to blind hole.In order to uniformly be laid with solder between liner outer wall and shell inner hole inner wall,
In technical solution of the present invention, solder is filled by selection in the form of solder piece.Specifically, it is exactly shape according to liner
And size, solder piece is cut, the solder piece after cutting will can be uniformly enclosed with uniform fold in the outer surface of liner
The liner of solder piece is put into shell inner hole, can be realized and is uniformly laid with solder between liner outer wall and shell inner hole inner wall.
Due between shell and inner lining material have biggish physical property difference, as fusing point, thermal expansion coefficient, specific heat,
It is thermally conductive etc., in technical solution of the present invention, preferably the above-mentioned shell filled with solder piece and liner assembly are carried out at repeatedly heat
Reason guarantees welding quality to enhance the intensity in welding gap.Specifically, it is normalizing first, i.e., is filled with solder piece to above-mentioned
Shell and liner assembly to be heated to brazing filler metal melts be liquid, be sufficient filling with after welded gaps cooling；It followed by anneals, to increase
The physical property of fierce fitting；It is finally quenching, to eliminate base material in the shear stress of commissure, finally realizes unimach
It is brazed with the inner hole of tungsten alloy.
One as technical solution of the present invention preferably specifically includes in step S2,
S21 warm-up phase: heating is filled with the shell and liner assembly of solder piece, improves the pearlite of temperature to shell
With under the transition temperature boundary of austenite in 30~40 degree Celsius ranges, a period of time is kept at this temperature；
The equal thermophase of S22: heating temperature is improved to the ferrite of shell and the transition temperature boundary of austenite, in this temperature
Lower holding a period of time；
S23 welds the stage: improving heating temperature to brazing filler metal fusing point, so that solder piece sufficiently melts, solder is sufficient filling with interior
Gap between lining and case weld face.
One as technical solution of the present invention is preferred, and liner, which is also matched, is arranged with rod-shaped counterweight, and the counterweight end is goed deep into
Shell inner hole is abutted with liner inner wall, by the gravity of counterweight, applies pressure to liner, so that in described in welding process
Lining is fitted closely with shell inner hole.
Wherein, inner hole includes the through-hole and blind hole of inside parts.
One as technical solution of the present invention is preferably additionally provided with counterweight supporting element on shell, counterweight support setting is being matched
On weight supporting element, for keeping the relative position of counterweight and shell constant, the phase of shell and inner liner location in welding process is realized
To stabilization.
One as technical solution of the present invention is preferred, and method for welding carries out preferably in vacuum environment, and vacuum degree is preferred
Not less than 1.33Pa.
One as technical solution of the present invention is preferred, the preferred AgCu50 of solder.
One as technical solution of the present invention is preferred, the preferred 0.1mm of pricker material thickness.
One as technical solution of the present invention is preferred, and solder piece is preferably fixed on outside liner in such a way that spot welding is combined
Surface.
One as technical solution of the present invention is preferred, and the heating time of step S3 preferably 12 hours.
In general, through the invention it is contemplated above technical scheme is compared with the prior art, have below beneficial to effect
Fruit:
1) method of technical solution of the present invention passes through solder optimized Selection, welding part surface active, roughness control, temperature
Optimization of profile is spent, the methods of weld gap matching optimization solves both high-strength steel (DT300) and tungsten alloy (95W) fusing point, ratio
The key problem in technology problems such as thermal capacitance, thermal expansion coefficient and the huge difference of elasticity modulus, obtain soldering joint strength 450MPa or more
High-intensitive weld seam improves the reliability of solder design.
2) method of technical solution of the present invention makees shell vacuum hardening using high temperature brazing as conditioning treatment normalizing
For secondary soldering, shell tempering makes dissimilar material soldering processes and case material heat treatment process as soldering destressing processing
It sufficiently combines, obtain high-intensitive high welded rate soldered fitting while guaranteeing shell high-strength tenacity.
3) method of technical solution of the present invention is accurately mated formation by solder, with reorientation pressurization and joint clearance of brazing matching, solution
The welding structure problem of tubular connected structure in deep blind hole of having determined, soldering connection is accurate, and steel/tungsten interface ratio of brazing area is high, Ke Yishi
The ratio of brazing area for now controlling deep blind hole inner arc Combined Welding junction is not less than 70%.
4) soldering and metal heating processing technology are combined by the method for technical solution of the present invention, quick using superhigh temperature
Normalizing, homogenizing refinement material；It breaks through conventional annealing system and it is completely soft to be reached using long-time heat preservation under DT300 steel A1 point for material
Change, granulation；Height low time vacuum heat treatment of quenching obtains all good lath martensite of obdurability+micro paralympic tissue, the shell heart
Portion's whole through hardening, strength test pass through examination.Meanwhile measure of the shell vacuum hardening as secondary soldering, steel and tungsten welding are strong
Degree is enhanced again.
Detailed description of the invention
Fig. 1 is that unimach and the tungsten alloy welded structure in blind hole are illustrated in the embodiment of technical solution of the present invention
Figure；
Fig. 2 is unimach and tungsten alloy the counterweight welded structure in blind hole in the embodiment of technical solution of the present invention
Schematic diagram；
Fig. 3 is that unimach and the solder piece of tungsten alloy vacuum brazing are cut out in the embodiment of technical solution of the present invention
Expanded view；
Fig. 4 is the normalizing procedure medium temperature of unimach and tungsten alloy vacuum brazing in the embodiment of technical solution of the present invention
Degree-time plot；
Fig. 5 is the annealing process medium temperature of unimach and tungsten alloy vacuum brazing in the embodiment of technical solution of the present invention
Degree-time plot
Fig. 6 is the quenching process medium temperature of unimach and tungsten alloy vacuum brazing in the embodiment of technical solution of the present invention
Degree-time plot
Fig. 7 is the low power shape of unimach and weld seam after tungsten alloy vacuum brazing in the embodiment of technical solution of the present invention
Looks figure；Wherein, Fig. 7 (a) be in the embodiment of technical solution of the present invention after steel and tungsten vacuum brazing weld seam under 8 times of stereoscopes
Shape appearance figure, Fig. 7 (b) be in the embodiment of technical solution of the present invention after steel and tungsten vacuum brazing weld seam in 100 times of optical microscopies
Under shape appearance figure；
Fig. 8 is unimach and the microstructure after tungsten alloy vacuum brazing in the embodiment of technical solution of the present invention
Figure；
Fig. 9 is the micro-organization chart in the embodiment of technical solution of the present invention after unimach quenching heat treatment.
Specific embodiment
In order to make the objectives, technical solutions, and advantages of the present invention clearer, with reference to the accompanying drawings and embodiments, right
The present invention is further elaborated.It should be appreciated that the specific embodiments described herein are merely illustrative of the present invention, and
It is not used in the restriction present invention.As long as in addition, technical characteristic involved in the various embodiments of the present invention described below
Not constituting a conflict with each other can be combined with each other.The present invention is described in more detail With reference to embodiment.
In the embodiment of technical solution of the present invention, mainly for the inner hole brazing problems of unimach and tungsten alloy, with
Common dissimilar material soldering tech is compared, and the difference of the soldering of unimach and tungsten alloy mainly has: (1) superhigh intensity
Physical characteristic between steel and tungsten alloy differs larger, and fusing point both especially, thermal expansion wash one's face and rinse one's mouth, specific heat capacity and springform
Amount difference is very big, and two kinds of materials are both immiscible or are not easy to be formed intermetallic compound, and soldering control is very difficult.It can specifically see below
Table:
1 unimach of table and tungsten-bast alloy physical characteristic
As shown in Figure 1, being the structural representation between the superhigh intensity steel sheel of technical solution of the present invention and tungsten alloy liner
Figure.In the embodiment of technical solution of the present invention, outer shell material is unimach DT300, and internal layer inner lining material is tungsten conjunction
Golden 95W.2 shape of tungsten alloy liner and the deep blind hole of shell 1 match, i.e. tungsten alloy liner outer diameter size makes it just may be used
To be put into deep blind hole, and tungsten alloy liner matches with deep blind via bottom shape, as shown in Figure 1 and Figure 2.
After soldering and heat treatment, the mechanical strength of unimach (DT300) and tungsten alloy (95W) soldered fitting is joined
Number σ b at least needs to reach 400MPa and 450MPa respectively；Postwelding ratio of brazing area between superhigh intensity steel sheel and tungsten alloy liner
It needs to reach 70% or more；The mechanical strength parameter σ b of unimach (DT300) shell needs to reach 1750MPa or more (mark
Standard needs to reach 75J/cm for 1650MPa), impact flexibility α k2(standard 65J/cm above2), hardness 47HRC~52HRC it
Between.Meanwhile tungsten alloy (95W) in shell inner hole depth dimensions error within 0.2mm；Unimach (DT300) shell
The size diameter difference of internal diameter φ 100mm is no more than 0.35mm；Unimach (DT300) shell straightness error exists
Within 0.30mm/m, i.e., the straight line error of every meter length is no more than 0.30mm.
By being analyzed unimach (DT300) and tungsten alloy (95W) soldering processes it is recognised that being brazed temperature
It is to be mutually related between degree, weld strength and outer housing material property (especially toughness).By solder sprawl test and
Connection reliability test, comprehensively considers quality, technique and cost, preferably uses in the embodiment of technical solution of the present invention
AgCu50 silver-based hard solder is brazed the preferred 0.1mm of thickness.The solder, which has, is free of Volatile Elements, and vacuum brazing effect is good etc.
Advantage.From the point of view of welding procedure angle, AgCu50 brazing filler metal fusing point is moderate, has good intensity, plasticity, thermal conductivity and anticorrosive
Property；Especially, the solder welding procedure temperature range and the matching degree of unimach heat treatment parameter are good.
Below using specific step to the superhigh intensity in technical solution of the present invention embodiment just with tungsten alloy inner hole pricker
Weldering and heat treatment complex method are further detailed.In the embodiment of technical solution of the present invention, soldering base material is preferably used
Unimach (DT300) and tungsten alloy (95W).It is specific welding step below:
(1) welding surface of unimach and tungsten alloy is handled.Unimach and tungsten alloy carry out welding it
Before, it needs to handle welding surface, reduces welding difficulty.Specifically, including following procedure: 1. selecting suitable dimension
Superhigh intensity steel sheel and tungsten alloy liner so that size is suitable between shell and liner, is mutually matched, meeting welding is needed
It asks；2. being cleaned to the superhigh intensity steel sheel and tungsten alloy liner welding surface selected, mainly shell and liner are welded
The greasy dirt and impurity in face are cleaned, and the welding quality of greasy dirt and impurity effect welding surface is prevented；3. to superhigh intensity steel shell
The welding surface of body and tungsten alloy liner is polished, so that the soldering joint strength that solder is formed between the welding surface of base material is more
Well, base material welding surface is bigger；4. to after polishing superhigh intensity steel sheel and tungsten alloy liner welding surface carry out further third
Ketone cleaning, washes away the impurity of face of weld；5. step 4. on the basis of, superhigh intensity steel sheel and tungsten alloy liner are welded
Face carries out surface active pickling, in favor of attachment of the solder on welding surface.
(2) solder is laid between unimach and the welding surface of tungsten alloy.By calculate superhigh intensity steel sheel with
Weld gap variation of the tungsten alloy liner in process of expansion and contraction chooses suitable solder to match with welding gap.This
In inventive technique scheme, it is preferred to use AgCu50 is as brazing solder, further, for shell and liner size, preferably adopts
Small―gap suture with solder and weld size in 2.0mm~5.0mm cooperates.When calculating filling solder, technical solution of the present invention
Embodiment in preferably by the moulding of Pro-E software, will be between welding design of part size, weld seam area, solder piece density, cooperation
The data summarizations such as gap calculate, so that it is determined that the quality of filling solder.In a preferred embodiment, shell 1 is closed at one end
Deep blind hole, shell total length 770mm, error are no more than 0.2mm；Hole depth 721.5mm；Housing exterior walls diameter 105mm, inner diameter
76.7mm.In the embodiment of technical solution of the present invention, the distance of the end of tungsten alloy liner threshold value shell depth blind hole is
391.67mm error is no more than 0.2mm.At this point, the filling solder quality being calculated is 217 grams；Simultaneously, it is contemplated that feeding and
Mismachining tolerance (gap control general overgauge), to guarantee enough weld seam ratios of brazing area, in the embodiment of technical solution of the present invention
Solder material weight is preferably 280 grams under above-mentioned size.Specifically, not being directly to fill out solder when carrying out solder filling
Enter the deep blind hole of unimach, but solder is first processed into certain thickness solder piece, then carries out locating filler.Generally
For, solder piece rolls by cold rolling, lattice deformability, and yield point is higher；And tungsten alloy liner is plugged on superhigh intensity steel sheel
Soldering in deep blind hole curved surface, the assembly of the filling positioning of solder and tungsten alloy during the brazing process are all weight difficult points.The technology of the present invention side
In the embodiment of case, the shape and size being preferably unfolded according to the solder amount of putting and solder bond circular arc camber suppress solder
The solder piece of formation is cut as desired, its spot welding combination is then fixed on tungsten liner outer surface (see Fig. 3), then again
The above-mentioned tungsten alloy liner for being enclosed with solder thin slice is mated formation and is put into the deep blind hole of shell.According to the difference of welding object size,
Required solder quality also can be variant.That is, needing first to be calculated according to its size when being brazed for specific base material
It obtains the quality of required solder, then solder thin slice is cut again, and after wrapping up the welding surface of liner, put
Enter in the deep blind hole of shell.
(3) unimach and tungsten alloy assembly that are filled with solder are brazed.In technical solution of the present invention, according to
According to 875 DEG C of AgCu50 brazing filler metal fusing point, the basic datas such as the transformation temperature A1 (690 DEG C) and A3 (850 DEG C) of DT300 steel pass through a system
Column technological experiment, the final optimum process temperature for determining steel and tungsten soldering is 920 DEG C.Specific brazing process includes: that 1. will fill out
Unimach and tungsten alloy assembly filled with solder are put into soldering oven at low temperatures, and vacuum is extracted into 10 in furnace-2Pa；②
It is slowly heated welding base metal and solder assembly, in A1 point (i.e. transition temperature circle of pearlite and austenite of unimach
Limit) 650 DEG C of preheating steps are set before, certain time is kept under 650 DEG C of preheating temperatures, to reduce thermal stress accumulation；3. plus
Thermal weld base material and solder assembly, in the A3 point (temperature that the transformation of ferrite and austenite starts or ends of unimach
Degree boundary) before be arranged 850 DEG C of heat preservation steps taken a step forward with further stabilized steel, tungsten and solder temperature in brazing filler metal melts
Weighing apparatus combination temperature, to improve solder tackness, mitigate subsequent heat brazing filler metal erosion problem；4. continuing to improve filled with solder
The temperature of unimach and tungsten alloy assembly, until optimum process temperature, then continuous heating is for a period of time.Skill of the present invention
In the embodiment of art scheme, the every 5 DEG C of progress campaign of AgCu50 brazing filler metal fusing point or more preferably is respectively adopted to brazing temperature, i.e.,
At 875 DEG C or more, every 5 DEG C are once tested.
In the embodiment of technical solution of the present invention, under above-mentioned process conditions, identical two pieces braze-welded structure is chosen every time
It is put into soldering oven simultaneously and carries out same treatment, after the completion of soldering, the strength of joint of two pieces weldment is tested, to determine optimised process
Parameter.Test process is shown in Table 2:
The brazing process variables and corresponding joints intensity that table 2 is tested
According to table 2, comparative test is as a result, optimization obtains steel and the optimal technological temperature of tungsten soldering joint strength is 920 DEG C.
That is, maintain the unimach for being filled with solder and tungsten alloy assembly in 920 DEG C of a period of times, so that solder sufficiently melts,
It is sufficient filling with the gap between tungsten alloy liner and superhigh intensity steel sheel.
(4) superhigh intensity steel sheel and tungsten alloy liner braze-welded structure further progress heat treatment reinforcement and weld seam are quenched
Enhancing technology.In the embodiment of technical solution of the present invention, for the mechanical property for guaranteeing superhigh intensity shell, design has three Re Chu
Science and engineering sequence: normalizing, soft annealing and vacuum hardening.It its detailed process and is analyzed as follows: the 1. high temperature brazing journey in step (3)
Sequence, as in the embodiment of technical solution of the present invention be directed to superhigh intensity steel sheel normalizing process, the purpose of the process be for
While carrying out soldering, further homogenizing, micronization processes material, need together to process shell and liner and solder
To certain temperature, preferably 920 DEG C in the embodiment of technical solution of the present invention, after keeping the temperature a period of time, it is cooled to room temperature, that is, is completed
Normalizing (soldering) process, it is preferable to determine the Temperature-time passes in soldering normalizing procedure in the embodiment of technical solution of the present invention
System's figure is as shown in Figure 4；2. next procedure is soft annealing.The ginseng of conventional annealing is breached in the embodiment of technical solution of the present invention
Numeral system degree continues to carry out heating for 12 hours to it at a temperature of the A1 of unimach point is slightly lower, with nodularization unimach
Tissue, reduces subsequent quenching distortion, further increases the machinability of superhigh intensity steel sheel, the reality of technical solution of the present invention
Apply in example it is preferable to determine soldering annealing process in Temperature-time relational graph it is as shown in Figure 5；3. to by normalizing and annealed
The unimach and tungsten alloy weldment of journey processing continue 895 DEG C of quenching treatments；Pass through quenching, an original weld seam
Shear stress release, the stress of the molten seam organization of weight reduces, steel/tungsten strength of joint enhancing to 450MPa or more；Shell vacuum
The measure as secondary soldering is quenched, weld strength is enhanced；The lath martensite tissue being had excellent performance, shell center portion
It quenches low time to handle by vacuum height and obtains all good lath martensite of obdurability+micro paralympic tissue, guarantee Strong caps performance
It is up to standard.It is preferable to determine Temperature-time relational graph such as Fig. 6 institutes in soldering quenching process in the embodiment of technical solution of the present invention
Show
Further principles analysis is carried out to the above process below.
In unimach and tungsten alloy brazing process, influence of steel/tungsten thermal expansion coefficient to soldered seam gap is most
Greatly.When technological design, by the structure size of both the above part, material thermal expansion coefficient and technological temperature parameter input formula:
Thermally expand size delta △ L=d × α × (ti-t0), calculate separately the change in size of brazing process outer housing Yu tungsten liner.Its
In: d is material diameter, and α is thermal expansion coefficient, ti-t0For temperature variation.When weld heating, tungsten liner heat at diameter phi 75
Dilation dimension exceeds the thermal expansion size 0.82mm of shell inner hole, has exceeded the welded gaps 0.3mm of shell and lining parts, institute
With tungsten liner and shell, there are certain flexible deformations.In addition, since shell and tungsten liner front end are that arc surface cooperates, in shell
The hole conical surface squeezes tungsten liner and is allowed to by upward component, if not considering flexible deformation, tungsten liner will be moved up, and pass through mould
Quasi- software can calculate tungsten liner it is hot when move up 0.1623mm, but match depth dimensions tolerance without departing from tungsten inside lining filling.
Specifically, when unimach and tungsten alloy soldering are heated, outer housing is relied on by radiant heating in vacuum, tungsten liner
The heat transfer of outside outer housing is heated, considers heat transfer radiation velocity, when just starting to be heated, solder and tungsten liner plus
Thermal velocity and actual temperature are lower than outer housing, shell expanded by heating, and allowing solder and liner, easily accurate dropping place arrives
Outer housing inner hole bottom.In addition, during the brazing process, interior lining, which is also applied with, matches in order to further ensure the accuracy of inner liner location
Weight, as shown in Fig. 2, 1 is superhigh intensity steel sheel, 2 be tungsten alloy liner, and 3 be counterweight, and 4 be recoil inserts and counterweight supporting element.
That is, 2 sets of liner in counterweight 4, it is vertically arranged in the blind deep hole of superhigh intensity steel sheel 1 together.The reality of technical solution of the present invention
It applies in example, counterweight is column, and size and the inner wall size of tungsten alloy liner match, and tungsten alloy liner has certain thickness
Degree, therefore the circle diameter of counterweight is less than the inner wall size of superhigh intensity steel sheel, it is heavy if do not gripped to counterweight
The heart is unstable, will affect welding quality.In technical solution of the present invention, recoil inserts and counterweight supporting element 4 are mounted on unimach
On shell, for counterweight 3 to be clamped and fixed, so that counterweight will not occur with respect to the position of centre of gravity of superhigh intensity steel sheel
Change.Further, when high temperature brazing, since the tungsten alloy 95W coefficient of expansion is much higher than the expansion system of unimach DT300
Number, at heating initial stage, superhigh intensity steel sheel elder generation expanded by heating, tungsten alloy lining temperature is not high at this time, and dilation dimension is also little,
The tungsten alloy liner for being enclosed with solder piece can easily be fallen into the deep blind hole of superhigh intensity steel sheel；But heating certain time
Afterwards, tungsten alloy lining temperature rises, and dilation dimension increased dramatically, at this time after the expansion of superhigh intensity steel sheel deep blind hole ruler
The very little peripheral dimension less than tungsten alloy liner, the inward pressure of super guiding principle intensity steel sheel is received so as to cause tungsten alloy liner,
Tungsten alloy liner uplink under the squeezing action of the outer shell inner hole conical surface, influences the accuracy of soldering places.At the same time, it melts
Solder be heated pressurization between the two in steel and tungsten, the squeezing action of the superhigh intensity steel sheel and tungsten alloy liner that are subject to,
Pressure and temperature promote and form conversion zone between two kinds of materials of solder and steel tungsten, improve the reliability of solder design.
In cooling procedure, solder is gradually condensed into solid-state, and the temperature of superhigh intensity steel sheel and tungsten alloy liner is also gradually
It reduces, interaction force between the two is gradually reduced, and welding gap is gradually increased.It is very good due to having under ag-cu solder high temperature
Ductility, most of not broken separation of contact surface can be kept in the weld gap gradually increased.Further, tungsten alloy
Liner is moved down due to the weight and technique counterweight by itself while cooling meat, original position is returned to, in this process
In, the solder between superhigh intensity steel sheel and tungsten alloy liner is by a shear stress.Therefore, to prevent postwelding cold
Base material is shunk excessive to the stretching travel of solder when but, and reserved unilateral gap is no more than 0.15mm before the two weldering.In order to reduce
The step of shear stress suffered by seam organization between unimach and tungsten alloy, the embodiment of technical solution of the present invention
(4) solder secondary fusion is made by the quenching process after soldering in, the stress of seam organization is released and redistributes, stress
Level substantially reduces.
Due to superhigh intensity steel sheel thickness great disparity, needs to carry out heating for multiple times and cooling in welding and heat treatment, will lead
Mutagens shape is larger.To reach Deformation control index, it is provided with normalizing process first in the embodiment of technical solution of the present invention, to subtract
It is small to be deformed than tolerance.The normalizing process of DT300 steel substantially in order to obtain tissue be most of martensites+a small amount of bainite+
The steel of micro troostite structure, tissue is closest with the specific volume of final quenching structure, by this process, can make most
Whole quenching distortion is relatively minimal.Secondly, reducing thermal stress influences, technical solution of the present invention in order to sufficiently eliminate machining stress
Furnace, the mode of ladder slow heating, using two ladder heat-insulation preheatings, to reduce stress deformation are entered using low temperature in embodiment.Again
It is secondary, in order to guarantee tungsten alloy liner and superhigh intensity steel sheel welding position accuracy, the implementation of technical solution of the present invention
In example, counterweight is applied with to tungsten alloy liner to reduce the straight line error of tungsten alloy soldering places, to guarantee outer housing and tungsten
The soldering of liner and gaps after quenching control are within the error range.Preferably apply counterweight in the embodiment of technical solution of the present invention
20kg.In addition, avoiding gas stifled in order to reduce the bubble in gap and generating weld seam bubble, above-mentioned soldering and heat treatment process are excellent
Choosing carries out under vacuum conditions.In the embodiment of technical solution of the present invention, when soldering preferably remain vacuum degree 1.33Pa with
On.
It after steel and tungsten vacuum brazing, after weld seam dissection, is observed through 8 times and 100 times of low powers, steel/tungsten weld seam is clear, connection
The defects of locating bubble-free, crackle, such as Fig. 7.In the high power metallographic observation using 1000 times, weld seam and DT300 steel and tungsten faying face
There are transition zone, after steel and tungsten vacuum brazing, weld seam and DT300 steel and tungsten faying face transition zone width be respectively 0.02mm and
0.005mm, such as Fig. 8.Superhigh intensity structure of steel after strengthening by this method is lath martensite pattern, sees Fig. 9.
The unimach that the present invention uses/tungsten alloy combination dissimilar material high temperature brazing connects and takes into account unimach
The complex technique method of ontology strenthen-toughening mechanizm, key problem in technology are vacuum brazing and heat-treatment of annealing, normalizing, strengthen quenching
The design of the precedence and specific process parameter of equal process programs combination.
The vacuum brazing of steel tungsten and heat treatment complex technique that the present invention studies include that key problem in technology has: 1) according to vacuum radiation
The material properties such as heating effect, the fusing point of solder, mobility and the specific heat and the thermal coefficient that stick together performance, steel and tungsten, in conjunction with zero
Part structure size, the austenite transition points of welding filler metal technological temperature and high-strength steel have worked out the temperature and time range of soldering,
It is controlled by the temperature slope of brazing process, the mild isothermal step setting of multiple tracks, reduces and thermally expand between steel/tungsten dissimilar material
Influence of the larger difference of coefficient to brazing quality.It is low with corresponding weld seam that soldering processes time-temperature curve is studied by Metallographic Analysis
Times pattern, welding line joint microstructure, component gradient distributional pattern, objectively evaluate brazed joint quality.Pass through examination
It tests and determines that optimization soldering time-temperature curve, soldered seam strength of joint reach 450MPa or more；By being loaded to solder, positioning form and
The matching optimization of soldered fitting gap size solves the ratio of brazing area technology controlling and process welding problem of tubular connected structure in blind hole,
Reach 70% or more.2) shell heat treatment synthesizing and the secondary soldering tech of steel/tungsten.Using superhigh temperature quick normalizing, homogenizing is thin
Change material；It breaks through conventional annealing system to reach material using long-time heat preservation under DT300 steel A1 point and soften completely, crystal grain ball
Change；Height low time vacuum heat treatment of quenching obtains all good lath martensite of obdurability+micro paralympic tissue, and shell center portion is all quenched
Thoroughly, strength test passes through examination.Measure of the shell vacuum hardening as secondary soldering simultaneously, steel and tungsten weld strength obtain again
Enhancing.
As it will be easily appreciated by one skilled in the art that the foregoing is merely illustrative of the preferred embodiments of the present invention, not to
The limitation present invention, any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should all include
Within protection scope of the present invention.
Claims (8)
1. the inner hole method for welding of a kind of unimach and tungsten alloy is welded to superhigh intensity for realizing by tungsten alloy liner
In steel sheel inner hole, which is characterized in that including
S1 uniformly coats solder piece on the welding surface of liner, the liner for being coated with solder piece is placed in shell inner hole, so that pricker
Tablet is uniformly laid between shell and the welding surface of liner；
S2 heating is filled with the shell and liner of solder piece, and heating temperature is arranged more than solder piece melting point；Continuous heating is extremely
Solder piece sufficiently melts, and solder is sufficient filling with the gap between liner and case weld face；
S3 anneals to the shell and liner weldment that handle through step S2；
S4 improves heating temperature to brazing filler metal melts, quenches to the shell and liner weldment that handle through step S3, from
And it realizes the inner hole of unimach and tungsten alloy and is brazed；
Wherein, it is specifically included in the step S2,
S21 warm-up phase: heating is filled with the shell and liner assembly of solder piece, improves temperature to the pearlite of shell and Austria
Under the transition temperature boundary of family name's body in 30~50 degree Celsius ranges, a period of time is kept at this temperature；
The equal thermophase of S22: heating temperature is improved to the ferrite of shell and the transition temperature boundary of austenite, is protected at this temperature
Hold a period of time；
S23 welds the stage: improve heating temperature to brazing filler metal fusing point so that solder piece sufficiently melts, solder be sufficient filling with liner with
Gap between case weld face.
2. unimach according to claim 1 and tungsten alloy inner hole method for welding, wherein the liner, which is also matched, to be arranged
There is rod-shaped counterweight, the counterweight end is goed deep into shell inner hole and abutted with liner inner wall, by the gravity of counterweight, applies to liner
Plus-pressure, so that liner described in welding process is fitted closely with shell inner hole.
3. unimach according to claim 2 and tungsten alloy inner hole method for welding, wherein be additionally provided on the shell
Counterweight supporting element, counterweight support are arranged on counterweight supporting element, for keeping the relative position of counterweight and shell constant, realize weldering
Shell and inner liner location is relatively stable in termination process.
4. described in any item unimach and tungsten alloy inner hole method for welding according to claim 1~3, wherein the pricker
Soldering method carries out preferably in vacuum environment, and vacuum degree is preferably not less than 1.33Pa.
5. unimach according to claim 1 or 2 and tungsten alloy inner hole method for welding, wherein the solder is preferred
AgCu50。
6. unimach according to claim 5 and tungsten alloy inner hole method for welding, wherein the pricker material thickness is excellent
Select 0.1mm.
7. unimach according to claim 1 or 2 and tungsten alloy inner hole method for welding, wherein the solder piece is excellent
The mode for gating spot welding combination is fixed on liner outer surface.
8. unimach according to claim 1 or 2 and tungsten alloy inner hole method for welding, wherein the step S3's
Heating time preferably 12 hours.
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| CN109590681B (en) * | 2018-11-19 | 2020-06-16 | 广西天正钢结构有限公司 | High-strength self-fastening steel structure joint and manufacturing method thereof |
| CN110977074B (en) * | 2019-11-21 | 2021-10-22 | 中国航发沈阳黎明航空发动机有限责任公司 | Furnace brazing method of nickel-based high-temperature alloy material |
| CN113523471B (en) * | 2021-07-06 | 2022-04-15 | 北京科技大学 | Diffusion welding method for tungsten-nickel-iron alloy and high-strength steel for preparing intermediate layer by reducing material |
| CN114807795B (en) * | 2022-04-29 | 2023-02-28 | 中南大学 | Method for improving performance of brazed chromium-zirconium-copper alloy and chromium-zirconium-copper alloy workpiece |
| CN115338494B (en) * | 2022-07-05 | 2023-03-21 | 中机智能装备创新研究院(宁波)有限公司 | Method for regulating residual stress of heterogeneous brazed joint |
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