CN106987793B - H13 steel mold nitrogenation treatment technology again - Google Patents
H13 steel mold nitrogenation treatment technology again Download PDFInfo
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- CN106987793B CN106987793B CN201710404495.8A CN201710404495A CN106987793B CN 106987793 B CN106987793 B CN 106987793B CN 201710404495 A CN201710404495 A CN 201710404495A CN 106987793 B CN106987793 B CN 106987793B
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C8/06—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases
- C23C8/08—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases only one element being applied
- C23C8/24—Nitriding
- C23C8/26—Nitriding of ferrous surfaces
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C8/02—Pretreatment of the material to be coated
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- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Solid-Phase Diffusion Into Metallic Material Surfaces (AREA)
Abstract
The present invention discloses a kind of H13 steel mold nitrogenation treatment technology again, it is characterised in that: for the H13 steel mold before nitrogen treatment, work belt surface is coated with rare earth-iron-boron.Technical advantage of the invention is as follows: (1) nitridation time is short, is remarkably improved production efficiency；(2) technological operation is simple, and low in cost without increasing special device.(3) nitriding result is more preferable, mold work belt surface can form the nitriding layer of 0.2~0.6mm, and most surface layer can form the white bright nitride layer of one layer of 10~20 microns of thick hard and compact, hardness is up to 1100~1200HV, therefore extrusion aluminum profile can be made to obtain the glossy surface close to mirror surface.
Description
Technical field
The present invention relates to technical field of metal material manufacture, and in particular to a kind of H13 steel mold nitrogenation treatment technology again.
Background technique
Aluminum profile needed for the various fields such as current building, rail traffic, automobile, ship, be essentially all by extruding and
Forming.Extrusion die is the core technology of aluminum profile industry, and the quality and service life of extrusion die directly affect aluminum profile
Quality and production cost.Extrusion die is formally using on the machine after design, machining, heat treatment, electric machining, die trial, finishing
Before, it usually needs surface carburization processing is carried out, to improve work surface hardness and wearability, this Nitrizing Treatment is known as first nitrogen
Change.Through after a period of time extruding production after, the nitration case of mold work belt surface be worn it is thinned, hardness reduce, cause to squeeze
Die mould material rough surface, it is therefore desirable to mold be unloaded from extruder, re-start Nitrizing Treatment after processing is clean, referred to as again
Secondary nitrogen treatment.In order to extend die life, this nitrogen treatment again usually be will do it 1~5 time.
The extrusion die material generallyd use now in industry is H13 steel, and the Nitrizing Treatment technology generallyd use is gas
Nitriding belongs to a kind of hard nitridation.Gas nitriding processing is exactly that ammonia is resolved into nitrogen and hydrogen at relatively high temperatures, therein
Partial activation nitrogen-atoms is adsorbed to mold steel surface and diffuses into steel substrate, forms the nitriding layer with high rigidity.With
First nitrogen treatment is different, again when nitrogen treatment, because die surface has the residual nitration case of certain depth, nitrogen atom concentration
Relatively first nitridation is high, therefore the more first nitrogen treatment of nitriding speed is slow, so the nitridation time needed is long, to reduce production effect
Rate.For the technology in terms of nitrogen treatment again, do not carried out further investigation in industry always, enterprise is nearly all according to warp
Test, using with nitrogenize essentially identical technique for the first time nitrogen treatment again carried out to extrusion die, be easy to appear nitrided case depth
Thin, the problems such as hardness is low, brittleness is high, ammonia utilization rate is low.Therefore, for extrusion die, nitrogen treatment carries out technical research again
And propose inventive process technology, it is the important topic that aluminum profile industry is badly in need of.
Existing research shows that rare earth element can accelerate the carburizing, nitriding, boronizing process of steel surface, but is usually to be added in
Promote multicomponent thermochemical treatment in penetration enhancer.Appropriate rare earth element is added in penetration enhancer, the preferable surface of toughness can be formed by multicomponent thermochemical treatment
Hardened layer and nitride layer, white layer, here it is so-called gas soft nitridings, but its formula is complicated, and technological operation is not easy to control, in aluminum profile
Extrusion die industrial application is few.Rare earth oxide, rare earth-iron-boron etc. all have facilitation, but existing report to nitriding process
Specific implementation method, implementation result are not described in, the gas of extruding die for aluminum shaped material is nitrogenized firmly, especially again
Nitriding process is not reported clearly more.
Summary of the invention
The technical problem to be solved by the present invention is in order to solve at present domestic extruding die for aluminum shaped material again nitrogen treatment when
Between long, the problems such as hardness is low, low efficiency, propose a kind of H13 steel mold of pretreatment process using coating rare earth-iron-boron again
Secondary nitrogen treatment new process.
Used technical solution to solve above-mentioned technical problem: a kind of H13 steel mold nitrogenation treatment technology again, it is special
Sign is: for the H13 steel mold before nitrogen treatment, work belt surface is coated with rare earth-iron-boron.
It may be preferred that the rare earth element in the rare earth-iron-boron is at least one of Ce, La, Y.
The rare earth-iron-boron applied be neutral organic solvent, ratio of the rare earth-iron-boron in the flux be 20~45 grams/
It rises.
It may be preferred that ratio of the rare earth-iron-boron in flux is 30~40 grams per liters.
Specifically, including the following steps:
Step 1: it is 0.4~0.8 μm that steel mold work belt surface, which is polishing to roughness,；
Step 2: rare earth-iron-boron, air dry cure are coated in the work belt surface of steel mold；
Step 3: steel mold is put into nitriding furnace, is first vented, and then heats to 450~520 DEG C, heat preservation 0.5~2.0
Hour, control ammonia dissociation rate 30~40%；
Step 4: being continuously heating to 530~560 DEG C, keeps the temperature 1~6 hour, and ammonia dissociation rate control is 35~45%；
Step 5: steel mold furnace cooling, and logical ammonia is kept, every to reduce by 50 DEG C, ammonia dissociation rate accordingly reduces by 3~5%,
After being cooled to 200~120 DEG C, it is passed through air and is cooled to room temperature.
It may be preferred that being warming up to 480~510 DEG C in the step 3,0.5~1.0 hour is kept the temperature, controls ammonia dissociation rate
30~35%.
In the step 4, be continuously heating to 550~560 DEG C, keep the temperature 2~4 hours, ammonia dissociation rate control for 38~
42%.
In the step 5, after being cooled to 150~120 DEG C, it is passed through air and is cooled to room temperature.
Extrusion die working face is directly with the die surface that is extruded material, and mold work belt surface is deformation material
Material is extruded the die hole periphery surface of mold, is the direct die-face for determining to squeeze out the shape and size of profile.It squeezed
The belt surface that works in journey bears severe friction, and finish and hardness directly affect the surface quality for squeezing out profile.Therefore it nitrogenizes
The emphasis of processing is to form dense sclerosis layer in work belt surface.The present invention is when mold is pre-processed in the work belt surface of mold
Coat one layer of rare earth-iron-boron film.Rare-Earth Element Chemistry property is living to be dialled, and activity is high, and ionic compound easily decomposes.Under high temperature
This rare earth-iron-boron easily decomposes, and generates the rare earth ion of high activity, to increase the activity of work belt steel surface, makes it more
It is easy attached nitrogen atom, and accelerates the diffusion of nitrogen-atoms.Therefore, it can be completed at nitridation within the shorter time using the present invention
Reason, and thicker, finer and close nitriding layer is obtained, improve mold working surface hardness and wearability.
It is lower (30~40%) that ammonia dissociation rate is controlled at 450~520 DEG C of first segment temperature in step 3, is to guarantee
Nitrogen atom concentration is sufficiently high, so that steel surface adsorbs more activated nitrogen atoms；The second segment temperature 530~560 in step 4
At DEG C, because temperature is higher, ammonia dissociation rate is controlled in higher range (35~45%), so as to when guaranteeing nitrogen atom concentration
Improve ammonia utilization rate；It is reduced in step 5 cooling procedure with temperature and reduces ammonia dissociation rate, be to guarantee activated nitrogen atom
Concentration, to obtain fine and close surface nitride hardened layer.
Compared with tradition again Nitriding Technology, technical advantage of the invention is as follows: (1) nitridation time is short.In general, using with
The identical technique of first nitrogen treatment is come out of the stove from exhaust, heating, heat preservation, cooling, is generally required 15~25 hours or even longer,
And nitriding process again of the invention is used, the entire processing time is not more than 10 hours, therefore is remarkably improved production efficiency；
(2) technological operation is simple.Pretreatment polishing, two-part nitrogen treatment temperature and ammonia dissociation rate control method of the invention is all and often
It is identical to advise technique, in work belt surface coating rare earth-iron-boron and last cooling procedure ammonia dissociation rate controlling party after only polishing
Method is different from common process.The operation of the two links is extremely simple, and low in cost without increasing special device.(3) nitrogen
It is more preferable to change effect.Using conventional nitridation process, the mold work belt surface of nitrogen treatment can form the infiltration of 0.1~0.3mm again
Nitrogen layer, but most surface layer cannot generally be formed high rigidity nitride layer, white layer (iron-nitride layer) or nitride layer, white layer it is relatively thin, it is not fine and close, because
This wear-resisting property is lower；And nitriding process again of the invention is used, mold work belt surface can form the infiltration of 0.2~0.6mm
Nitrogen layer, and most surface layer can form the white bright nitride layer of one layer of 10~20 microns of thick hard and compact, hardness is up to 1100~
1200HV, therefore extrusion aluminum profile can be made to obtain the glossy surface close to mirror surface.
Specific embodiment
Below by comparison implementation, the present invention is further illustrated:
Battery of tests is directed to four sets extrusion dies: A, B is to have also passed through two-wheeled extruding and twice after nitrogen treatment
Two sets of identical extrusion dies, C are the mold for have passed through three-wheel and squeezing and nitrogenizing three times, and D is that have passed through four-wheel to squeeze and four nitrogen
The mold of change.Technique according to the invention, by four mold working surfaces be polishing to roughness be 0.4~0.8 μm, A, C,
The work belt surface of tri- mold of D and the test position of selection coat pre-assigned lanthanum chloride alcoholic solution, and B mold is not coated by；
It frames up together with other molds to be processed after natural air drying and is put into nitriding furnace；It is first vented 0.5 hour, then heats to 510
DEG C, 0.5 hour is kept the temperature, ammonia dissociation rate 32% is controlled；It is further heated up to 545 DEG C, 3 hours are kept the temperature, ammonia dissociation rate control is
45%；Dissection power supply after to temperature, mold furnace cooling, and logical ammonia is kept, and it is every to reduce by 50 DEG C, ammonia dissociation rate is reduced by 3%；Most
After be cooled to 150 DEG C after be passed through air and be cooled to room temperature.Hardness test is carried out after coming out of the stove, and tracks and records squeezing effect.As a result
As shown in table 1.
Second group of test is carried out using small test piece.It is squeezed from a set of by two-wheeled and twice after nitrogen treatment because cracking is scrapped
The work belt position of extrusion die cut two pieces of sheet specimens, number is E, F respectively.Wherein E sample presses above-mentioned A, C, D mold
Pretreating process polished and coated, F sample is not coated by, then with other mold shove charges.First exhaust 0.5 hour, so
After be warming up to 510 DEG C, keep the temperature 0.5 hour, control ammonia dissociation rate 32%；It is further heated up to 545 DEG C, 3 hours are kept the temperature, ammonolysis craft
Rate control is 42%；Dissection power supply after to temperature, mold furnace cooling, and logical ammonia is kept, ammonia dissociation rate holding 45% is constant.It is cold
But it to ammonia is closed after 150 DEG C, is passed through air and is cooled to room temperature.Hardness test is carried out to specimen surface after coming out of the stove.As a result such as table 2
It is shown.
1 first group of test result of table
2 second groups of test results of table
As shown in table 1, technique according to the invention carries out the tri- sets of extrusion dies of embodiment A, C, D for using 2~4 times
Nitrogen treatment again, obtains the working surface of high rigidity, and wear-resisting property is excellent；And not by present invention coating rare earth-iron-boron
The comparative example B mold of (lanthanum chloride), surface hardness is significant lower, and next time nitridation before complete profile extrusion weight ratio A,
C, nearly 1 times of tri- sets of extrusion die major generals of D, embody technical advantage of the invention.
As shown in table 2, as a comparison case, although the pretreatment of E sample and nitriding process all press technological operation of the invention,
Ammonia dissociation rate is not controlled rationally by the present invention in nitridation later period cooling procedure, surface is just not easily formed adequate thickness
The white bright nitride layer of hard and compact；As another comparative example, the F sample of uncoated rare earth-iron-boron is eventually formed white bright
Nitride layer is thinner, therefore wear-resisting property is lower.
Claims (4)
1. a kind of H13 steel mold nitrogenation treatment technology again, it is characterised in that: the H13 steel mold is before nitrogen treatment, work
Make belt surface and be coated with rare earth-iron-boron, the rare earth element in the rare earth-iron-boron is at least one of Ce, La, Y, is applied
Rare earth-iron-boron be neutral organic solvent, ratio of the rare earth-iron-boron in the solvent is 20~45 grams per liters, including is walked as follows
It is rapid:
Step 1: it is 0.4~0.8 μm that steel mold work belt surface, which is polishing to roughness,；
Step 2: rare earth-iron-boron, air dry cure are coated in the work belt surface of steel mold；
Step 3: steel mold is put into nitriding furnace, is first vented, and then heats to 450~520 DEG C, keeps the temperature 0.5~2.0 hour,
Controlling ammonia dissociation rate is 30~40%；
Step 4: being continuously heating to 530~560 DEG C, keeps the temperature 1~6 hour, and ammonia dissociation rate control is 35~45%；
Step 5: steel mold furnace cooling, and logical ammonia is kept, every to reduce by 50 DEG C, ammonia dissociation rate accordingly reduces by 3~5%, cooling
To after 200~120 DEG C, it is passed through air and is cooled to room temperature.
2. H13 steel mold according to claim 1 nitrogenation treatment technology again, it is characterised in that: in the step 3, rise
Temperature keeps the temperature 0.5~1.0 hour to 480~510 DEG C, and control ammonia dissociation rate is 30~35%.
3. H13 steel mold according to claim 1 nitrogenation treatment technology again, it is characterised in that: in the step 4, after
It is continuous to be warming up to 550~560 DEG C, 2~4 hours are kept the temperature, ammonia dissociation rate control is 38~42%.
4. H13 steel mold according to claim 1 nitrogenation treatment technology again, it is characterised in that: in the step 5, drop
Temperature is passed through air and is cooled to room temperature to after 150~120 DEG C.
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| CN201710404495.8A CN106987793B (en) | 2017-06-01 | 2017-06-01 | H13 steel mold nitrogenation treatment technology again |
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| CN106987793B true CN106987793B (en) | 2019-07-30 |
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| CN216201077U (en) * | 2020-12-17 | 2022-04-05 | 武汉市华敏智造科技有限责任公司 | Integrated intelligent flow controller |
| CN115216682B (en) * | 2022-09-19 | 2022-12-09 | 中特泰来模具技术有限公司 | Automobile die-casting die steel and preparation method thereof |
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| CN1067684A (en) * | 1991-06-15 | 1993-01-06 | 徐厚国 | Hot treating method for elastic parts |
| CN101285163A (en) * | 2008-05-12 | 2008-10-15 | 十堰市郧齿汽车零部件有限公司 | Nitriding method for engine timing gear with rigid tooth face |
| CN101435065A (en) * | 2007-11-15 | 2009-05-20 | 冯俊杰 | Low temperature rare earth catalytic cementation soft nitriding processing technology for high speed steel mould |
| CN102268632A (en) * | 2011-04-19 | 2011-12-07 | 哈尔滨意锋稀土材料开发有限公司 | Solid rare earth nitriding accelerator |
| CN102864407A (en) * | 2011-07-06 | 2013-01-09 | 天津上热金属科技有限公司 | Rare earth catalyzed nitrocarburizing technology |
| CN103981482A (en) * | 2014-05-05 | 2014-08-13 | 福建省南平铝业有限公司 | Aluminum extrusion die and surface strengthening and toughening treatment process |
-
2017
- 2017-06-01 CN CN201710404495.8A patent/CN106987793B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1067684A (en) * | 1991-06-15 | 1993-01-06 | 徐厚国 | Hot treating method for elastic parts |
| CN101435065A (en) * | 2007-11-15 | 2009-05-20 | 冯俊杰 | Low temperature rare earth catalytic cementation soft nitriding processing technology for high speed steel mould |
| CN101285163A (en) * | 2008-05-12 | 2008-10-15 | 十堰市郧齿汽车零部件有限公司 | Nitriding method for engine timing gear with rigid tooth face |
| CN102268632A (en) * | 2011-04-19 | 2011-12-07 | 哈尔滨意锋稀土材料开发有限公司 | Solid rare earth nitriding accelerator |
| CN102864407A (en) * | 2011-07-06 | 2013-01-09 | 天津上热金属科技有限公司 | Rare earth catalyzed nitrocarburizing technology |
| CN103981482A (en) * | 2014-05-05 | 2014-08-13 | 福建省南平铝业有限公司 | Aluminum extrusion die and surface strengthening and toughening treatment process |
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Address after: 528225 No. 3, Hongling 4th Road, changhongling Industrial Park (phase II), Shishan town, Nanhai District, Foshan City, Guangdong Province (residence declaration) Patentee after: Guangdong Huachang Group Co.,Ltd. Patentee after: JIANGSU HUACHANG ALUMINUM FACTORY Co.,Ltd. Address before: 528225 No. 3, Hongling 4th Road, changhongling Industrial Park, Shishan town, Nanhai District, Foshan City, Guangdong Province Patentee before: GUANGDONG HUACHANG ALUMINUM FACTORY Co.,Ltd. Patentee before: JIANGSU HUACHANG ALUMINUM FACTORY Co.,Ltd. |
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