CN104741499A - Sandwich layer forging die and preparation method of forging die sandwich layer surfacing - Google Patents

Sandwich layer forging die and preparation method of forging die sandwich layer surfacing Download PDF

Info

Publication number
CN104741499A
CN104741499A CN201510171656.4A CN201510171656A CN104741499A CN 104741499 A CN104741499 A CN 104741499A CN 201510171656 A CN201510171656 A CN 201510171656A CN 104741499 A CN104741499 A CN 104741499A
Authority
CN
China
Prior art keywords
welding
sandwich
layers
die
built
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.)
Granted
Application number
CN201510171656.4A
Other languages
Chinese (zh)
Other versions
CN104741499B (en
Inventor
周杰
张建生
沈力
卢顺
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
CHONGQING JIEPIN TECHNOLOGY Co Ltd
CHONGQING JIEXIN LIANZHONG MECHANICAL & MANUFACTURE Co Ltd
Chongqing University
Original Assignee
Chongqing University
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Chongqing University filed Critical Chongqing University
Priority to CN201510171656.4A priority Critical patent/CN104741499B/en
Publication of CN104741499A publication Critical patent/CN104741499A/en
Application granted granted Critical
Publication of CN104741499B publication Critical patent/CN104741499B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21JFORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
    • B21J13/00Details of machines for forging, pressing, or hammering
    • B21J13/02Dies or mountings therefor
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23KSOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K9/00Arc welding or cutting
    • B23K9/04Welding for other purposes than joining, e.g. built-up welding
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23PMETAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
    • B23P15/00Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
    • B23P15/24Making specific metal objects by operations not covered by a single other subclass or a group in this subclass dies

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Plasma & Fusion (AREA)
  • Mounting, Exchange, And Manufacturing Of Dies (AREA)
  • Forging (AREA)

Abstract

The invention discloses a sandwich layer forging die and a preparation method of forging die sandwich layer surfacing. The sandwich layer forging die is used for surfacing a layer of sandwich layer soft welding material which is better in plasticity and lower in yield strength than a cast steel substrate and a double-metal gradient surfacing material between the cast steel substrate and the double-metal gradient surfacing material; the preparation method of the forging die sandwich layer surfacing comprises the following steps of taking cast steel as the cast steel substrate, and welding a sandwich layer soft material on a substrate layer; surfacing a transition layer material on a substrate of a sandwich layer welded, welding and covering all sandwich materials to form a surfacing transition layer; welding a high-temperature wearing layer material; tempering to distress after the completion of the welding, and then mechanically processing to obtain a mould. The sandwich layer forging die provided by the invention is long service life and high in loading capacity of the cast steel substrate. According to the method provided by the invention, the critical bottleneck problems that the forging die is low in life and the die is high in manufacturing cost can be solved thoroughly, the die forging forming of various materials can be supported at high temperature and high pressure, and a brand new manufacturing method can be provided for forging die manufacturing.

Description

The preparation method of a kind of sandwich of layers forging die and the built-up welding of forging die sandwich of layers
Technical field
The invention belongs to technical field of mold, be specifically related to the preparation method of a kind of sandwich of layers forging die and the built-up welding of forging die sandwich of layers.
Background technology
Along with the manufacturing development of national weight equipment, the equipment manufactures such as large aircraft, shipbuilding need rapid hoisting power.Large-scale stamp forging hydraulic press (80,000 tons of press) maximum in the world arises at the historic moment, its forging die used has been widely used in the large-scale forging part manufacturing in the fields such as Aeronautics and Astronautics, nuclear power, petrochemical industry, as large airframe framework, undercarriage, engine turbine disk etc., the forging material of these forging mainly comprises aluminium alloy, high temperature alloy, titanium alloy etc., all needs to adopt forging die to be shaped.But, the forming temperature of difficult-to-deformation material (high temperature alloy, titanium alloy etc.) large forgings is high, in forging and molding process because of forging and the contacting dies time long, it is high that mould bears pressure, and the temperature rise of die cavity top layer is fast, temperature is increased to rapidly more than 700 DEG C, cause mold work field strength, hardness reduces rapidly, cause that die deformation is very large, wearing and tearing are very serious, die life is extremely low, the distortion of die forging 1-2 part rear mold is up to more than 10mm, and mould is of serious failure the problem such as can not to re-use.
At present, only have materials such as adopting H13 steel to prepare large-scale stamp forging hydraulic press forging die, the need of production of large-scale forging die hydraulic press could be met; But although some extension of life when adopting forging H13 steel moald-cavity to manufacture forging die, H13 steel is expensive, and forging stock material and heat treatment after forging expense comparatively common process method improve nearly 1 times, and forging die manufacture cost is quite high.Therefore, manufacturing cost is high, die life the extremely low critical bottleneck having become the large-scale difficult-to-deformation material die forging of restriction and produced, also become the critical bottleneck that can large-scale stamp forging hydraulic press be afforded to use.Find a kind of service life that can significantly improve forging die, the forging die preparation method of die manufacturing cost can be reduced simultaneously, become the art problem demanding prompt solution.
Summary of the invention
For prior art above shortcomings, the object of this invention is to provide the sandwich of layers forging die that a kind of service life is longer, bearing capacity is higher.
Another object of the present invention is to provide the preparation method of a kind of forging die sandwich of layers built-up welding, the method can extend life-span, the shortening new product development cycle of forging die preferably, simultaneously can reduce die manufacturing cost again, fundamentally solve the critical bottleneck problem of large-scale difficult-to-deformation material die forging and die manufacturing cost costliness extremely low with die life.
Realize above-mentioned purpose, the present invention adopts following technical scheme: a kind of sandwich of layers forging die, comprises cast steel substrate A, transition zone C and high-temperature wearable layer D; Built-up welding one deck sandwich of layers B between cast steel substrate A and transition zone C; Better, yield strength is lower for the more described cast steel substrate A of described sandwich of layers B and transition zone C plasticity;
Wherein, the plastic range of sandwich of layers B is: δ percentage elongation >=14.7%, ψ shrinkage factor >=31.2%; Yield strength scope is: σ s yield strength >=550MPa.
Preferably, the δ percentage elongation of sandwich of layers B is 14.7% ~ 20%, ψ shrinkage factor be 31.2% ~ 36%, σ s yield strength is 550 ~ 570 MPA.
A preparation method for forging die sandwich of layers built-up welding, comprises the steps:
1) adopt cast steel to water as die matrix material and outpour die matrix to be welded; Wherein, built-up welding surplus is reserved at die cavity position; Reserved built-up welding surplus thickness depending on concrete mould kind and model, generally can reserve 40 ~ 90 mm.
2) on the die matrix to be welded poured into a mould in step 1), along the shape of reserved built-up welding place, the good and soft wlding of yield strength is low sandwich of layers of built-up welding plasticity, is welded to 14 ~ 16 mm under Die cavity profile line; Described plasticity is good and yield strength is low refers to that its mechanical performance index can reach following standard: σ syield strength>=550MPa, σ btensile strength>=760MPa, δ percentage elongation>=14.7%, ψ shrinkage factor>=31.2%, hardness 30 ~ 35HRC; Like this; when obtained mould is by after high-pressure peak stress; sandwich of layers plays cushion effect between transition zone and cast steel substrate; first the even micro-plastic deformation of elastic deformation is produced; by rapid for high-pressure peak stress expansion recedes; the safety of available protecting cast steel substrate, the peak stress value can not born because of cast steel substrate is too high, and causes cast steel substrate to break.
3) in step 2) weld on the die matrix of sandwich of layers, along the shape reserving built-up welding place surplus shape and sandwich of layers, built-up welding intensity and the higher transition zone wlding material of hardness, all cover sandwich of layers material and encase, and 8 ~ 11 mm under continuing to be welded to Die cavity profile line; Described intensity and hardness is higher refers to that its mechanical performance index can reach following standard: σ syield strength>=790MPa, σ btensile strength>=1100MPa, δ percentage elongation>=11.7%, ψ shrinkage factor>=28.9%, hardness 45 ~ 50HRC; Like this, transition zone can be combined well with sandwich of layers, effectively can be connected again with the cast steel substrate in mould upstream region, can also be combined well with high-temperature wearable layer subsequently.Due to adding of sandwich of layers material; stress spread between transition zone and cast steel substrate becomes more even; below die cavity, region of stress concentration can protect the safety of cast steel substrate effectively, and prevents buffer layer material from occurring formation of crack when bearing horizontal tensile stress.
4) weld on the die matrix of transition zone in step 3), built-up welding high-temperature wearable layer wlding material, cover the main wear-resisting working region of mould or whole wear areas, be welded to 4 ~ 6 mm on die cavity outline line; The mechanical performance index of described high-temperature wearable layer wlding material can reach following standard: σ syield strength>=1000MPa, σ btensile strength>=1400MPa, δ percentage elongation>=9.6%, ψ shrinkage factor>=26.5%, hardness 50 ~ 55HRC; This layer of strong hardness than transition zone and sandwich of layers all high, percentage elongation, shrinkage factor, impact flexibility and high-temperature behavior are good, for wear-resisting with thermal fatigue resistance ergosphere, play a major role in forging die mold work.By the collaborative compatibility combination of above-mentioned three layers of weld overlay materials, because sandwich of layers material has certain deformability when bearing high pressure, can make be extended the service life of high-temperature wearable layer and transition zone.
5) mould after three built-up welding is repeated retarded cooling process after double tempering, then the mould after second time slow cooling is placed in atmosphere, carry out air cooling to room temperature; Wherein, temperature is 530 ~ 570 DEG C, slow cooling temperature to 160 ~ 180 DEG C; This is because mould can produce the instability such as martensite, austenite tissue in welding heat affected zone, there is larger internal stress simultaneously; And if mold cools down excessive velocities, be easy to produce hardened structure, cause the defects such as crackle; Tempering slow cooling process obtains stable tempered martensite, can improve structure stability, makes mould in use no longer structural transformation occur, thus its physical dimension and property retention are stablized; Eliminate internal stress, to improve mold use performance and to stablize its physical dimension simultaneously; Also it is improved ductilityor toughness, the mechanical property of adjustment mould is to meet instructions for use; In order to prevent the generation of one-step temper embrittlement, have employed high tempering, namely temperature controls at 530 DEG C ~ 570 DEG C; In order to prevent the generation of temper brittleness, have employed double tempering retarded cooling process; After second time slow cooling, mould is placed in air and carry out air cooling to room temperature; This is because after below slow cooling to 180 DEG C, Microstructure and properties is basicly stable, can be cooled to room temperature in atmosphere.
6) machining is carried out to the mould after step 5) air cooling, mold portions size is put in place, obtained above-mentioned sandwich of layers forging die.The position of forging die heap postwelding, have higher hardness, general machining cannot ensure size.The mold cavity surface very out-of-flatness of heap postwelding, first can process plane with the dise knife of surface grinding machine or digital control processing, pincers worker is rule by drawing, first electricity consumption pulse lathe shapes, carry out the cutting of little surplus again with numerical control milling, or directly use grinder buffing, each several part size of mould is put in place.
As optimization, in described step 1), need to carry out 920 DEG C of quenchings and in the process of 650 DEG C of tempering watering the welding mould for the treatment of outpoured, and oil cooling is to room temperature.Like this, can eliminate remaining as-cast structure, it is unlikely overheated to make again to organize, and avoids obtaining annealed structure, makes its comprehensive mechanical performance meet product requirement.
Step 2 in above-mentioned technology), 3) and 4) in, as optimization, before built-up welding, welding mould need be treated and carry out surface cleaning process, the oxide skin of removal overlay surface and welding slag after three built-up welding complete.Wherein said surface cleaning process refers to remove sand, oxide skin, greasy dirt, iron rust, burr and casting flaw.Specifically can remove shrinkage cavity with carbon arc air gouging, the casting flaws such as be full of cracks, then remove sand, oxide skin, greasy dirt, iron rust, burr etc. with pneumatic grinder rifle, cleaning mold surface.
As optimization, in described step 2), 3) and 4) in, in weld deposit process, knock mould by phased manner make it vibrate, vibration frequency is 20 ~ 40 beats/min; Can reach like this makes deposited metal extend, and prevents hydrogen embrittlement, refinement strengthening position crystal grain, round and smooth corner angle, reduce stress and concentrate, improve dimensional accuracy stability, eliminate fine crack and the slag defect on built-up welding top layer, the object suppressing crackle to occur, deposited metal is improved fatigue life; Wherein crystal grain thinning not only can improve the intensity of material, can also improve its plasticity and toughness; The stress that double-layer metal resurfacing welding strengthening process is produced is discharged preferably, makes the better of each overlay cladding competency, toughness combination.
As further optimization, in described step 2) and 3) in, sandwich of layers material only covers the partial arcs (40 ~ 60%) of base layer according to maximum stress distribution, instead of conformal welding covers matrix reserved area completely; This is because sandwich of layers material yield strength is very low; perfect condition is even semi-solid material; Main Function is spread by maximum stress; and then use buffer layer material sandwich of layers to be encased completely; sandwich of layers plays cushion effect between transition zone and cast steel substrate; first the even micro-plastic deformation of elastic deformation is produced, by rapid for high-pressure peak stress expansion recedes, the safety of available protecting cast steel substrate.
As further optimization, the described step 2 in above-mentioned technology), 3) and 4) in, need CO be led to during built-up welding 2protect with the mist of Ar, the volume ratio of described gas is: Ar80% ~ 90%, CO 210% ~ 20%; Take to pass into CO 2with the mist of Ar, molten bath and molten drop can be protected, by them and air exclusion, prevent weld seam from producing the defects such as pore; Electric arc heat under the compression of shielding gas flow is concentrated, and speed of welding is very fast, and molten bath is less, and heat affected area is narrow, and weldment post welding distortion is little; And owing to have employed rich argon mixed air mode, the splashing in welding process also obviously reduces, improve welding quality.
In above-mentioned steps 2), 3) and 4) in, as one-step optimization again, during welding, welding wire feeding speed is 5 ~ 8M/min, welding current 360 ~ 440A, weldingvoltage 35 ~ 36V; Choosing of above-mentioned parameter scope is because when weldingvoltage is too low, have the tendency of adhesion mother metal; Voltage is too high, and arc phenomenon obviously increases, and molten bath is unstable, splashes and also increases; Welding current increases, and the fusion penetration of welding bead, molten wide, heap height increase all thereupon, and dilution rate slightly declines, but electric current is excessive, and splashing can increase; Along with the increase of speed of welding, the molten wide and heap of welding bead is high to be reduced, and fusion penetration and dilution rate increase, but weldering speed is too high, and arc generation ratio can be made to increase, and for controlling certain dilution rate, ensure overlay properties, speed of welding general control is at 5 ~ 8M/min; Suitable welding parameter, Absorbable organic halogens molten bath, prevents from splashing, controls dilution rate etc., improve the overlay properties obtained.
In described step 2), 3) and 4) in, as the optimization of a step again, built-up welding front mold need be preheated to 450 ~ 500 DEG C, and in weld deposit process, mold temperature need remain on more than 300 DEG C; Like this, mould can keep uniform temperature when built-up welding, makes the impact reducing temperature difference between deposited metal and mother metal, avoids the many disadvantages brought from heat affected area; And if weld does not carry out preheating, because the sharp popular drama of sweating heat is cold, its result can make high carbon cast steel mother metal generate martensite, and weld hardens, and structure property and mechanical performance degenerate, the accident that even generation crack etc. are fatal.
Tradition forging industry is main using 5CrNiMo, 5CrMnMo, H13 etc. as mould steel at present, these steel grades have certain quenching degree, elevated temperature strength and impact flexibility, but under high-temperature high-pressure state, the life-span is very low and prevailing price is higher, is difficult to be applied to difficult-to-deformation material die forging forging die.Difficult-to-deformation material (high temperature alloy, titanium alloy) forging forging die is prepared according to the original invention of applicant " method (ZL200910104604X) of forging die is prepared in a kind of double-metal layer built-up welding based on cast steel substrate ", face again die-forging forming temperature higher, forging and mould due to pressurize time of contact longer, the problems such as resistance of deformation is larger, are difficult to ensure the higher life-span.Therefore, applicant proposed a kind of forging die sandwich of layers and manufacture new method, namely be based on the original invention of applicant " method (ZL200910104604X) of forging die is prepared in a kind of double-metal layer built-up welding based on cast steel substrate " basis, the plasticity ratio that built-up welding one deck is closed between cast steel substrate and transition zone more better soft material---sandwich of layers wlding, under high pressure allow sandwich of layers that the even small plastic deformation of larger elastic deformation occurs, by the rapid diffusive attenuation of concentrated peak stress below mold cavity, and be delivered on cast steel substrate layer with approaches uniformity distributed stress, thus the maximum stress suffered by cast steel substrate is lowered, cast steel substrate is safer when pressure-bearing, peak stress is avoided directly to cause cast steel substrate to crack, and then cause mould fracture failure.Due to adding of sandwich of layers material, the stress spread between transition zone and cast steel substrate becomes more even, and below die cavity, region of stress concentration can protect the safety of cast steel substrate effectively, and prevents buffer layer material from occurring formation of crack bearing horizontal tensile stress.In addition, because sandwich of layers material has certain deformability when bearing high pressure, can make be extended the service life of high-temperature wearable layer and transition zone; The method can to support under hot conditions the die-forging forming of the difficult-to-deformation material under more high pressure and higher temperature.
Large-scale difficult-to-deformation material die forging forging die sandwich of layers manufactures new method and is prepared, and cast steel substrate lower cost materials is utilized, and can realize the saving of resource and recycling of material, meets the requirement of the sustainable development of country and society; Simultaneously because be casting mold, the production time is corresponding shortening also, saves time cost; The proposition of sandwich of layers of the present invention greatly reduces built-up welding wlding and welding job amount, and the function of cushion turn improves the pressure-bearing security of cast steel substrate, also improves mold use security simultaneously; When adopt after mould invalidation repair again time because transition zone and high-temperature wearable layer material fairly good, can direct build-up wear-resistant layer material, bonding strength is good, and rehabilitation cost is low; Moreover, the present invention adopts sandwich of layers surfacing manufacturing technology, Strengthening and Toughening process is carried out to forging die surface, makes working region meet or exceed the performance of common die steel 5CrNiMo, 5CrMnMo or H13, achieve the object reducing costs, save energy and reduce the cost and improve die life.
The mould applications of action line other type in the industry will set up a collection of new and high technology with great market prospect, the sustainable development in chain this field of promotion after the present invention promotes, become energy-saving consumption-reducing, demonstration project that circulation develops in a healthy way.
Compared to existing technology, the present invention has following beneficial effect:
1, sandwich of layers Service Life of Forging Die of the present invention improves more than 50%, by each gradient function layer of built-up welding, collaborative play each gradient layer the different efficacies that rises, comprehensively improve the performance of cast steel forging die, improve its working region intensity and toughness; By built-up welding one deck soft-centre layer welding material in the middle of sandwich of layers forging die, when mould bears high pressure stress, sandwich of layers plays cushion effect between transition zone and cast steel substrate, make the stress distribution on cast steel substrate layer more even, by rapid for high-pressure peak stress expansion recedes, the peak stress value that cast steel substrate is born is minimized, peak stress is avoided directly to cause cast steel substrate to crack, cause mould fracture failure, thus improve the pressure-bearing security of cast steel substrate, the bearing capacity improving sandwich of layers mould and general safety performance.
2, the adding of sandwich of layers material of the present invention; the stress spread between transition zone and cast steel substrate is made to become more even; below die cavity, region of stress concentration can protect the safety of cast steel substrate effectively, and prevents buffer layer material from occurring formation of crack when bearing horizontal tensile stress.In addition, because sandwich of layers material has certain deformability when bearing high pressure, can make be extended the service life of high-temperature wearable layer and transition zone.
3, the proposition of sandwich of layers of the present invention greatly reduces built-up welding wlding and welding job amount, saves raw material and workload; And the forging die that the inventive method is obtained, adopt when repairing again after mould invalidation because transition zone and high-temperature wearable layer material fairly good, can direct build-up wear-resistant layer material, bonding strength is good, and rehabilitation cost is low; Design of forging die manufacture with manufacture again, the field such as prepared by key position reparation, material, resource circulation utilization and green circulatory manufacture has wide using value and development prospect.
4, the inventive method can be applicable to the preparation of large-scale difficult-to-deformation material forging die, can significant prolongation forging die life-span, improve cast steel substrate forging die bearing capacity, the life-span of obtained sandwich of layers forging die mould improves more than 50%; Fundamentally solve the critical bottleneck problem being applicable to the large-scale difficult-to-deformation material die forging of large-scale stamp forging hydraulic press and die manufacturing cost costliness extremely low with die life, revolutionary innovative approach is provided to forging die manufacture, the method can support the die-forging forming of the various types of materials under high temperature and high pressure, die industry is had to the meaning that cannot estimate.
5, sandwich of layers surfacing manufacturing technology of the present invention is adopted, Strengthening and Toughening process is carried out to forging die surface, the bearing capacity of cast steel substrate mould is greatly improved, working region meets or exceeds the performance of common die steel 5CrNiMo, 5CrMnMo or H13, may be used for the preparation of large-scale stamp forging hydraulic press forging die, and no longer need to use expensive H13 etc. to prepare large-scale stamp forging hydraulic press forging die, the overall cost saving more than 20%, reduce die manufacturing cost, manufacturing cost shared by reduction forging, have more economical, shorten the construction cycle of new product.
6, the present invention makes cast steel substrate lower cost materials be utilized, and can realize the saving of resource and recycling of material, meets the requirement of the sustainable development of country and society; Adopt more cheap cast steel as die matrix material, whole mould to be fortified directly pours into shape to be welded, compared with original new molding jig, save forging process and machining time, cost reduces, and matrix material utilization rate is high, brand-new mold developing cycle shortens, and saves time cost.
Accompanying drawing explanation
Fig. 1 is the structural representation of the sandwich of layers forging die exemplified in detailed description of the invention;
Fig. 2 is the mold sections structural representation for illustration of each overlay cladding situation in detailed description of the invention;
In Fig. 2, A is die matrix to be welded; B is sandwich of layers; C is transition zone; D is high-temperature wearable layer; E is die cavity outline line.
Detailed description of the invention
Below in conjunction with the drawings and specific embodiments, the present invention is described in further detail, if no special instructions raw materials used in embodiment, be common commercially available.
Take the preparation process of concrete sandwich of layers forging die mould as shown in Figure 1 below, the present invention is described in further details, because the present invention to be each step of the inventive method to the place that prior art makes creative contribution, instead of be the selection of forging die shape and kind, therefore the forging die only listing a kind of concrete structure in this detailed description of the invention is described in detail to this method, but each step in the inventive method, for the forging die of difformity and kind, all should be considered as being applicable.
Need the sandwich of layers forging die prepared to be the counterdie of forging mould in this detailed description of the invention, shape as shown in Figure 1, comprises cast steel substrate A, transition zone C and high-temperature wearable layer D; Built-up welding one deck sandwich of layers B between cast steel substrate A and transition zone C; Better, yield strength is lower for the more described cast steel substrate A of described sandwich of layers B and transition zone C plasticity;
Wherein, the plasticity of sandwich of layers B is: δ percentage elongation 14.7%, ψ shrinkage factor 31.2%; Yield strength is: σ s yield strength 550MPa.
The sandwich of layers built-up welding preparation method of above-mentioned sandwich of layers forging die comprises the following steps:
A, employing cast steel water as die matrix material and outpour die matrix A to be welded, and wherein, built-up welding surplus thickness 40 mm is reserved at die cavity position; The cast steel adopted selects high carbon chromium manganese steel G35CrNiMo to pour into a mould, and adopt common pouring technology, mold cavity position is half-circle-arc shape, reserved allowance; Water the forging die mould that outpours 920 DEG C of quenchings and after 650 DEG C of temper, oil cooling to room temperature, to improve its mechanical property.
B, on die matrix to be welded A along design shape in advance at reserved built-up welding surplus place the first good and soft wlding B of yield strength is low sandwich of layers of built-up welding plasticity, sandwich of layers thickness and weld length are determined by stress distribution, 40% of covering base layer radian; Under the effect of sandwich of layers stress spread, peak stress should be reduced within the scope of cast steel substrate safe handling, is welded to about 15 mm under Die cavity profile line; Wherein, described plasticity is good and yield strength is low refers to that its mechanical performance index can reach following standard: σ s(yield strength)>=550MPa, σ b(tensile strength)>=760MPa, δ (percentage elongation)>=14.7%, ψ (shrinkage factor)>=31.2%, hardness 35 ~ 36HRC.During concrete enforcement, can select close with cast steel substrate composition, or the low hydrogen type bead welding wire that performance is more or less the same in plasticity etc. after identical heat treatment, as CD126 etc.Like this, sandwich of layers can be combined well with matrix, and what improve cast steel substrate can welding characteristic and intensity, effectively connects base layer and transition zone and high-temperature wearable layer, reduction wlding cost.
C, on the matrix of weld clip central layer material, along reserved built-up welding surplus place's shape and sandwich of layers shape, secondary built-up welding intensity and the higher transition zone C of hardness, all encase sandwich of layers material, and about 10 mm under continuing to be welded to Die cavity profile line; Wherein said intensity and hardness is higher refers to that its mechanical performance index can reach following standard: σ s(yield strength)>=790MPa, σ b(tensile strength)>=1100MPa, δ (percentage elongation)>=11.7%, ψ (shrinkage factor)>=28.9%, hardness 45 ~ 50HRC.Due to adding of sandwich of layers material, the stress spread between transition zone and cast steel substrate becomes more even, and below die cavity, region of stress concentration can effectively be protected the safety of cast steel substrate and prevent buffer layer material from occurring formation of crack bearing horizontal tensile stress.During concrete enforcement, can select with cast steel substrate close with sandwich of layers composition, or the low hydrogen type bead welding wire that performance is more or less the same in strong hardness and toughness etc. after identical heat treatment, as CD650.Like this, transition zone can be combined well with sandwich of layers and matrix, effectively connects base layer, sandwich of layers and high-temperature wearable layer, reduces wlding cost.
D, on transition zone three built-up welding high-temperature wearable layer D, be welded to about 5 mm on die cavity outline line; Usually, the thickness of three built-up welding strengthening layers is about 40 mm, covers mold work position; Wherein on outline line, about 5 mm are reserved machine-finish allowance; The mechanical performance index of its strengthening layer D is: σ s(yield strength)>=1000MPa, σ b(tensile strength)>=1400MPa, δ (percentage elongation)>=9.6%, ψ (shrinkage factor)>=26.5%, hardness 50 ~ 55HRC; Being combined by the organic compatibility of three layers of weld overlay materials, because sandwich of layers material has certain deformability when bearing high pressure, can make be extended the service life of high-temperature wearable layer and transition zone.During concrete enforcement, can select that strong hardness is high, the good low hydrogen type bead welding wire of toughness, as CDCo etc.; This layer of strong hardness can be made all high than C, and percentage elongation, shrinkage factor, impact flexibility and high-temperature behavior are good, as wear-resisting with thermal fatigue resistance ergosphere, play a major role in forging die mold work.
E, the mould after three built-up welding repeated retarded cooling process after double tempering, wherein temperature is 550 DEG C, slow cooling temperature to 180 DEG C.After second time slow cooling, mould is placed in air and carry out air cooling to room temperature.
F, machining is carried out to the mould after air cooling, mold portions size is put in place, obtained sandwich of layers forging die as shown in Figure 1.The position of forging die heap postwelding, have higher hardness, general machining cannot ensure size.The mold cavity surface very out-of-flatness of heap postwelding, first can process plane with the dise knife of surface grinding machine or digital control processing, pincers worker is rule by drawing, first electricity consumption pulse lathe shapes, carry out the cutting of little surplus again with numerical control milling, or directly use grinder buffing, each several part size of mould is put in place.
In the specific implementation, before the built-up welding of above-mentioned steps b, welding mould need be treated and carry out built-up welding strengthening pre-treatment, comprise: 1) die surface cleaning, remove sand, oxide skin, greasy dirt, iron rust, burr and casting flaw;
2) overall preheated mold to 450 DEG C;
3) insulation material coating mould, will treat that the mold cavity of built-up welding comes out; Process temperature >=300 DEG C.
In the weld deposit process of step b, c and steps d, need:
1) automatic CO is adopted 2, Ar mist (protective gas volume ratio: Ar80%, CO 220%) protect bead-welding technology, use Miller welding wire machine to carry out a sandwich of layers B built-up welding along die cavity on to be fortified of mould, solder wire convey speed is 7M/min, welding current 400A, weldingvoltage 36V.This layer is welded to about 15 mm under die cavity outline line.
2) automatic CO is adopted 2, Ar mist (protective gas ratio: Ar80%, CO 220%) protect replating technique, use Miller welding wire machine to carry out transition zone C bis-built-up welding along die cavity on to be fortified of mould, solder wire convey speed is 7M/min, welding current 400A, weldingvoltage 36V.This layer is welded to about 10 mm under die cavity outline line.
3) strengthening process point multilayer is carried out.After built-up welding last layer alloy material, remove oxide skin and the welding slag of overlay surface.
4) three built-up welding: then built-up welding specific alloy material D(high-temperature wearable layer on the weld layer after removing surface).Solder wire convey speed is 7M/min, welding current 400A, weldingvoltage 36V.This layer thickness 15 about mm.
5) oxide skin and the welding slag of overlay surface is finally removed.
In whole welding process, if mold temperature is lower than 300 DEG C, must shove charge preheating again; Be welded in process, side weld limit hammer firmly knocks.Wherein, as shown in Figure 2, in figure, A is steel casting die matrix to each overlay cladding structure, and B is built-up welding sandwich of layers, and C is built-up welding transition zone, and D is built-up welding strengthening layer, and E is the actual die cavity outline line of mould.
Above-mentioned steps e is for completing post weld heat treatment, comprises during concrete enforcement:
1) first time destressing tempering: complete the carrying out at once of built-up welding melts down intensification, charging temperature≤450 DEG C, heating-up time 0.4 h, heating-up temperature 550 DEG C ± 20 DEG C, temperature retention time calculates according to the every 50 millimeters of insulations of the biggest size of element of module for 1 hour, and temperature retention time should guarantee mould and die preheating heat penetration.
2) first time slow cooling: after first time destressing tempering, is placed in insulation sand pit by die body; Insulation sand pit is made up of the common river sand of average diameter of particles 1 mm, and insulation sand pit temperature maintains 180 DEG C; Bury completely with sand by die body, temperature retention time >=12h, takes out sand pit by mould afterwards; Temperature monitoring in process is completed by infrared thermometer.
3) second time destressing tempering: taken out from insulation sand pit by die body and enter second time destressing tempering, technological specification is as first time destressing tempering.
4) second time slow cooling: after mould completes second time destressing tempering, be placed on by die body in insulation sand pit and start second time slow cooling, technological specification is as first time slow cooling.
5) air cooling: mould complete second time slow cooling after temperature 180 DEG C, from insulation sand pit take out after placement carry out air cooling in atmosphere to room temperature.Now in die body, most of Transformation of Retained Austenite is martensite, and makes martensite eliminate internal stress, and now, surfacing part hardness is higher than die body hardness.
The mould obtained after above-mentioned steps e finally carries out machining through step f again, the complete forging die finished product of sandwich of layers of final obtained shape as described in Figure 1.Its finished product die mold cavity surface hardness average out to 50 ~ 55HRC, flawless, the defect such as to be mingled with.Sandwich of layers can be combined well with matrix, plays the maximum stress effect reducing cast steel substrate and bear.Transition zone C can be combined well with sandwich of layers and matrix, and mechanical performance index is a little better compared with after cast steel substrate modifier treatment, plays transition connection function, strengthens matrix mould simultaneously.Strengthening layer D strong hardness improves a lot than transition zone C, percentage elongation, shrinkage factor, impact flexibility and high-temperature behavior are good, play the object improving mold cavity competency, toughness.By the collaborative compatibility effect of each gradient function layer, comprehensively improve G35CrNiMo mould, improve the performances such as its working region intensity, toughness, the forging die mould produced through solid forging can be replaced.
In this forging die actual experiment, sandwich of layers forging die can improve more than 50% die life, the significant prolongation life-span of forging die; And decrease die change number of times, decrease downtime, shorten new product development cycle; Also mitigate the labour intensity of workman simultaneously, utilization rate of equipment and installations is improved greatly.
Because most importantly the place that the present invention makes creative contribution for prior art is the of method step own, therefore in a specific embodiment, a lot of data or numerical value are the optimal values announced, and all do not enumerate different numerical value with regard to each concrete number range and are described.As long as should regard as these numerical value to belong to number range described in description of the present invention, just can implement the present invention and realize goal of the invention, only just implementation result may be relatively more poor.
What finally illustrate is, above embodiment is only in order to illustrate technical scheme of the present invention and unrestricted, although with reference to preferred embodiment to invention has been detailed description, those of ordinary skill in the art is to be understood that, can modify to the technical scheme of invention or equivalent replacement, and not departing from aim and the scope of technical solution of the present invention, it all should be encompassed in the middle of right of the present invention.

Claims (6)

1. a sandwich of layers forging die, comprises cast steel substrate, transition zone and high-temperature wearable layer; It is characterized in that, built-up welding one deck sandwich of layers between cast steel substrate and transition zone; The plastic range of described sandwich of layers is: δ percentage elongation >=14.7%, ψ shrinkage factor >=31.2%; Yield strength scope is: σ s yield strength >=550MPa.
2. a preparation method for forging die sandwich of layers built-up welding, is characterized in that, comprises the steps:
1) adopt cast steel to water as die matrix material and outpour die matrix to be welded; Wherein, built-up welding surplus is reserved at die cavity position;
2) on the die matrix to be welded poured into a mould in step 1), along the shape of reserved built-up welding place, the good and sandwich of layers wlding that yield strength is low of built-up welding plasticity;
3) in step 2) weld on the die matrix of sandwich of layers, along the shape reserving built-up welding place surplus shape and sandwich of layers, built-up welding intensity and the higher transition zone wlding material of hardness, all cover sandwich of layers material and encase, and 8 ~ 11 mm under continuing to be welded to Die cavity profile line;
4) weld on the die matrix of transition zone in step 3), built-up welding high-temperature wearable layer wlding material, cover the main wear-resisting working region of mould or whole wear areas, be welded to 4 ~ 6 mm on die cavity outline line;
5) mould after three built-up welding is repeated retarded cooling process after double tempering, then the mould after second time slow cooling is placed in atmosphere, carry out air cooling to room temperature;
6) machining is carried out to the mould after step 5) air cooling, mold portions size is put in place, obtain sandwich of layers forging die described in claim 1.
3. the preparation method of forging die sandwich of layers built-up welding according to claim 2, is characterized in that, in described step 1), die matrix to be welded selects high carbon chromium manganese steel to pour into a mould.
4. the preparation method of forging die sandwich of layers built-up welding according to claim 2, is characterized in that, in described step 1), reserved built-up welding surplus thickness is 40 ~ 90 mm.
5. the preparation method of forging die sandwich of layers built-up welding according to claim 2, is characterized in that, described step 2) in sandwich of layers be welded to 14 ~ 16 mm under Die cavity profile line.
6. the preparation method of forging die sandwich of layers built-up welding according to claim 2, is characterized in that, described step 2) in sandwich of layers built-up welding cover 40 ~ 60% of base layer radian.
CN201510171656.4A 2015-04-13 2015-04-13 Sandwich layer forging die and preparation method of forging die sandwich layer surfacing Active CN104741499B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201510171656.4A CN104741499B (en) 2015-04-13 2015-04-13 Sandwich layer forging die and preparation method of forging die sandwich layer surfacing

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201510171656.4A CN104741499B (en) 2015-04-13 2015-04-13 Sandwich layer forging die and preparation method of forging die sandwich layer surfacing

Publications (2)

Publication Number Publication Date
CN104741499A true CN104741499A (en) 2015-07-01
CN104741499B CN104741499B (en) 2017-05-24

Family

ID=53582073

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201510171656.4A Active CN104741499B (en) 2015-04-13 2015-04-13 Sandwich layer forging die and preparation method of forging die sandwich layer surfacing

Country Status (1)

Country Link
CN (1) CN104741499B (en)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108607945A (en) * 2018-05-17 2018-10-02 湖北三环锻造有限公司 3D wldings print die multilayered coating structure and coating thickness determine method
CN108746374A (en) * 2018-07-20 2018-11-06 重庆大学 A kind of preparation method of the hot stamping forming die insert with conformal cooling channel
CN109570368A (en) * 2018-12-05 2019-04-05 重庆江东机械有限责任公司 A method of preparing ultra-high strength steel hot stamping forming die
CN110153350A (en) * 2019-06-24 2019-08-23 重庆大学 A kind of heavy-duty forging die tool and its manufacturing method
CN110180983A (en) * 2019-05-23 2019-08-30 重庆大学 A kind of profile-followed reticular structure hot forged mould of type cavity surface layer and preparation method thereof
CN113151641A (en) * 2021-04-21 2021-07-23 中山市江润金属压铸有限公司 Mold activation method capable of prolonging service life of mold
CN113145954A (en) * 2021-03-30 2021-07-23 广西天正钢结构有限公司 Bridge welding device and bridge welding method
CN113151749A (en) * 2021-04-28 2021-07-23 重庆大学 High-toughness die forged steel base material, sandwich layer forging die and preparation method thereof
CN114309534A (en) * 2021-12-29 2022-04-12 恒新增材制造研究中心(佛山)有限公司 Die-casting die and preparation method thereof

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113174541B (en) * 2021-04-28 2022-11-01 重庆大学 High-strength die forged steel base material, sandwich layer forging die and preparation method thereof
CN113174540B (en) * 2021-04-28 2022-11-01 重庆大学 Low-cost die forged steel base material, sandwich layer forging die and preparation method thereof

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5620160A (en) * 1979-07-27 1981-02-25 Mitsubishi Heavy Ind Ltd Padding method by spraying aluminum
US4277108A (en) * 1979-01-29 1981-07-07 Reed Tool Company Hard surfacing for oil well tools
CN1438088A (en) * 2003-03-27 2003-08-27 上海宝山热喷涂厂 Large rooler hard-surface build-up welding repairing method
CN101310914A (en) * 2007-05-22 2008-11-26 上海宝钢设备检修有限公司 Surfacing welding rod of transition layer of sink roller for melted zinc bath and surfacing technique
CN101628374A (en) * 2009-08-11 2010-01-20 重庆大学 Method for preparing forging mould by double-layer metal resurfacing welding based on cast steel substrate
CN102950363A (en) * 2012-10-16 2013-03-06 河北钢铁股份有限公司唐山分公司 Overlaying repair process for winch drum
CN103009015A (en) * 2013-01-13 2013-04-03 邯郸市永固冶金备件有限公司 Method for manufacturing double metal composite wear-resistant metallurgical rollers

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4277108A (en) * 1979-01-29 1981-07-07 Reed Tool Company Hard surfacing for oil well tools
JPS5620160A (en) * 1979-07-27 1981-02-25 Mitsubishi Heavy Ind Ltd Padding method by spraying aluminum
CN1438088A (en) * 2003-03-27 2003-08-27 上海宝山热喷涂厂 Large rooler hard-surface build-up welding repairing method
CN101310914A (en) * 2007-05-22 2008-11-26 上海宝钢设备检修有限公司 Surfacing welding rod of transition layer of sink roller for melted zinc bath and surfacing technique
CN101628374A (en) * 2009-08-11 2010-01-20 重庆大学 Method for preparing forging mould by double-layer metal resurfacing welding based on cast steel substrate
CN102950363A (en) * 2012-10-16 2013-03-06 河北钢铁股份有限公司唐山分公司 Overlaying repair process for winch drum
CN103009015A (en) * 2013-01-13 2013-04-03 邯郸市永固冶金备件有限公司 Method for manufacturing double metal composite wear-resistant metallurgical rollers

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
付礼成: "辊压机的挤压辊表面堆焊技术研究", 《中国优秀硕士学位论文全文数据库(工程科技Ⅰ辑)》 *
佚名: "辊压机挤压辊堆焊材料的选择", 《HTTP://WWW.ARCEQ.COM/ZHN/NEWS_WZ.JSP?PID=1335777361958》 *

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108607945A (en) * 2018-05-17 2018-10-02 湖北三环锻造有限公司 3D wldings print die multilayered coating structure and coating thickness determine method
CN108746374A (en) * 2018-07-20 2018-11-06 重庆大学 A kind of preparation method of the hot stamping forming die insert with conformal cooling channel
CN109570368A (en) * 2018-12-05 2019-04-05 重庆江东机械有限责任公司 A method of preparing ultra-high strength steel hot stamping forming die
US11465195B2 (en) 2019-05-23 2022-10-11 Chongqing Jiepin Technology Co., Ltd Hot-forging die with conformal meshy structured cavity surface layer and preparation method thereof
CN110180983A (en) * 2019-05-23 2019-08-30 重庆大学 A kind of profile-followed reticular structure hot forged mould of type cavity surface layer and preparation method thereof
WO2020232775A1 (en) * 2019-05-23 2020-11-26 重庆杰品科技股份有限公司 Hot-forging die with conformal network structure on surface layer of cavity and preparation method therefor
CN110153350A (en) * 2019-06-24 2019-08-23 重庆大学 A kind of heavy-duty forging die tool and its manufacturing method
CN113145954A (en) * 2021-03-30 2021-07-23 广西天正钢结构有限公司 Bridge welding device and bridge welding method
CN113145954B (en) * 2021-03-30 2023-03-24 广西天正钢结构有限公司 Bridge welding device and bridge welding method
CN113151641A (en) * 2021-04-21 2021-07-23 中山市江润金属压铸有限公司 Mold activation method capable of prolonging service life of mold
CN113151749B (en) * 2021-04-28 2022-07-12 重庆大学 High-toughness die forged steel base material, sandwich layer forging die and preparation method thereof
CN113151749A (en) * 2021-04-28 2021-07-23 重庆大学 High-toughness die forged steel base material, sandwich layer forging die and preparation method thereof
CN114309534A (en) * 2021-12-29 2022-04-12 恒新增材制造研究中心(佛山)有限公司 Die-casting die and preparation method thereof

Also Published As

Publication number Publication date
CN104741499B (en) 2017-05-24

Similar Documents

Publication Publication Date Title
CN104741499B (en) Sandwich layer forging die and preparation method of forging die sandwich layer surfacing
CN101628374B (en) Method for preparing forging mould by double-layer metal resurfacing welding based on cast steel substrate
CN109468634B (en) Process method for recovering precision of rolling mill step pad by laser cladding technology
CN101767262B (en) Reproducing method of forging mold by using composite build-up welding
CN105290703B (en) A kind of method that hot roll is worn with submerged arc overlay welding and laser melting coating reparation
CN103182618B (en) Roll forging die enabling surfacing manufacturing renovation technique
CN103084703B (en) A kind of large-scale interior empty steel-casting mends built-up welding reproducing method by replacing a damaged part
CN103255412B (en) High hardness material laser cladding process method for roller work surface
CN104722702B (en) Supercritical unit high temperature steam pipeline forging molding process
CN103706921A (en) Build up welding repair method of supporting roller of hot continuous rolling finishing mill
CN105779861B (en) A kind of wear-resisting high vanadium nitrogen high-speed steel shaped roll and its manufacture method
CN105506530A (en) Mold surface composite strengthening method
CN103252622A (en) Hook tail frame body machining technology
CN104532131B (en) A kind of method promoting milling train slitting wheel work-ing life
CN106381488B (en) Preparation method of continuous casting crystallizer foot roller coating
CN104162761A (en) Flywheel crack repair method
CN109570368A (en) A method of preparing ultra-high strength steel hot stamping forming die
CN104141131A (en) Process for repairing piston ring groove
CN105441844B (en) A kind of extrusion blooming method of male sportsman ingot casting
KR101489052B1 (en) Repairing methods for slab of the continuous casting machine mold by using of the Laser and its productions
CN101767268A (en) Preparation method of forging mold by using composite build-up welding and spray welding method
CN106111717B (en) A kind of aluminium alloy extrusion mould splits the restorative procedure of bridge and its mould of reparation
CN108213304B (en) Fist-type large-scale hot forging die with bionic structure and manufacturing method thereof
CN107962167B (en) A kind of method that founding remanufactures roll
CN104999228A (en) Steel casting surface quality processing technology

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
TA01 Transfer of patent application right
TA01 Transfer of patent application right

Effective date of registration: 20170425

Address after: 400044 Shapingba District Sha Street, No. 174, Chongqing

Applicant after: Chongqing University

Applicant after: Chongqing Jiepin Technology Co., Ltd.

Applicant after: CHONGQING JIEXIN LIANZHONG MECHANICAL & MANUFACTURE CO., LTD.

Address before: 400044 Shapingba District Sha Street, No. 174, Chongqing

Applicant before: Chongqing University

GR01 Patent grant
GR01 Patent grant