CN1067929A - The nitriding method of steel - Google Patents
The nitriding method of steel Download PDFInfo
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- CN1067929A CN1067929A CN91104154.0A CN91104154A CN1067929A CN 1067929 A CN1067929 A CN 1067929A CN 91104154 A CN91104154 A CN 91104154A CN 1067929 A CN1067929 A CN 1067929A
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- gas
- nitrogenize
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- steel
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- 238000000034 method Methods 0.000 title claims abstract description 47
- 229910000831 Steel Inorganic materials 0.000 title claims description 35
- 239000010959 steel Substances 0.000 title claims description 35
- 238000005121 nitriding Methods 0.000 title claims description 25
- 238000010438 heat treatment Methods 0.000 claims abstract description 23
- 229910052731 fluorine Inorganic materials 0.000 claims abstract description 15
- 239000011737 fluorine Substances 0.000 claims abstract description 12
- PXGOKWXKJXAPGV-UHFFFAOYSA-N Fluorine Chemical compound FF PXGOKWXKJXAPGV-UHFFFAOYSA-N 0.000 claims abstract 3
- 239000007789 gas Substances 0.000 claims description 61
- QKCGXXHCELUCKW-UHFFFAOYSA-N n-[4-[4-(dinaphthalen-2-ylamino)phenyl]phenyl]-n-naphthalen-2-ylnaphthalen-2-amine Chemical compound C1=CC=CC2=CC(N(C=3C=CC(=CC=3)C=3C=CC(=CC=3)N(C=3C=C4C=CC=CC4=CC=3)C=3C=C4C=CC=CC4=CC=3)C3=CC4=CC=CC=C4C=C3)=CC=C21 QKCGXXHCELUCKW-UHFFFAOYSA-N 0.000 claims 1
- 239000000203 mixture Substances 0.000 abstract description 19
- 150000004767 nitrides Chemical class 0.000 abstract description 5
- 230000008569 process Effects 0.000 description 23
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 16
- 239000000047 product Substances 0.000 description 15
- KRHYYFGTRYWZRS-UHFFFAOYSA-M Fluoride anion Chemical compound [F-] KRHYYFGTRYWZRS-UHFFFAOYSA-M 0.000 description 10
- 229910052757 nitrogen Inorganic materials 0.000 description 10
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 9
- 238000012545 processing Methods 0.000 description 8
- 238000001816 cooling Methods 0.000 description 5
- 238000005336 cracking Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 5
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 4
- 238000004140 cleaning Methods 0.000 description 4
- 230000006378 damage Effects 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 4
- 238000004334 fluoridation Methods 0.000 description 4
- 238000012546 transfer Methods 0.000 description 4
- 230000004913 activation Effects 0.000 description 3
- 239000006227 byproduct Substances 0.000 description 3
- 238000005255 carburizing Methods 0.000 description 3
- 150000001875 compounds Chemical class 0.000 description 3
- 238000009792 diffusion process Methods 0.000 description 3
- 230000008676 import Effects 0.000 description 3
- 125000004433 nitrogen atom Chemical group N* 0.000 description 3
- 238000005406 washing Methods 0.000 description 3
- 239000002912 waste gas Substances 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- 229910045601 alloy Inorganic materials 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- 229910021529 ammonia Inorganic materials 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 230000008878 coupling Effects 0.000 description 2
- 238000010168 coupling process Methods 0.000 description 2
- 238000005859 coupling reaction Methods 0.000 description 2
- 239000011159 matrix material Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 229910052756 noble gas Inorganic materials 0.000 description 2
- 238000002161 passivation Methods 0.000 description 2
- 230000005855 radiation Effects 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 239000003566 sealing material Substances 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 239000000758 substrate Substances 0.000 description 2
- 239000000725 suspension Substances 0.000 description 2
- 239000002699 waste material Substances 0.000 description 2
- MIZLGWKEZAPEFJ-UHFFFAOYSA-N 1,1,2-trifluoroethene Chemical group FC=C(F)F MIZLGWKEZAPEFJ-UHFFFAOYSA-N 0.000 description 1
- 229910000851 Alloy steel Inorganic materials 0.000 description 1
- 229910000975 Carbon steel Inorganic materials 0.000 description 1
- XWROUVVQGRRRMF-UHFFFAOYSA-N F.O[N+]([O-])=O Chemical compound F.O[N+]([O-])=O XWROUVVQGRRRMF-UHFFFAOYSA-N 0.000 description 1
- CMUBZTZNXGBJMQ-UHFFFAOYSA-N F[N] Chemical compound F[N] CMUBZTZNXGBJMQ-UHFFFAOYSA-N 0.000 description 1
- 229910000760 Hardened steel Inorganic materials 0.000 description 1
- XSTXAVWGXDQKEL-UHFFFAOYSA-N Trichloroethylene Chemical compound ClC=C(Cl)Cl XSTXAVWGXDQKEL-UHFFFAOYSA-N 0.000 description 1
- 230000032683 aging Effects 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- LDDQLRUQCUTJBB-UHFFFAOYSA-N ammonium fluoride Chemical compound [NH4+].[F-] LDDQLRUQCUTJBB-UHFFFAOYSA-N 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 239000010962 carbon steel Substances 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000002939 deleterious effect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000005868 electrolysis reaction Methods 0.000 description 1
- 238000003682 fluorination reaction Methods 0.000 description 1
- 125000001153 fluoro group Chemical group F* 0.000 description 1
- 230000004927 fusion Effects 0.000 description 1
- 239000008246 gaseous mixture Substances 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- QJGQUHMNIGDVPM-UHFFFAOYSA-N nitrogen group Chemical group [N] QJGQUHMNIGDVPM-UHFFFAOYSA-N 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 238000002203 pretreatment Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 238000010926 purge Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000005057 refrigeration Methods 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000003351 stiffener Substances 0.000 description 1
- 238000010301 surface-oxidation reaction Methods 0.000 description 1
- 238000009423 ventilation Methods 0.000 description 1
Images
Classifications
-
- 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
-
- 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
- C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
- C23C4/02—Pretreatment of the material to be coated, e.g. for coating on selected surface areas
-
- 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
- C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
- C23C4/18—After-treatment
-
- 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
- C23C8/06—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
- C23C8/34—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 more than one element being applied in more than one step
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Plasma & Fusion (AREA)
- Solid-Phase Diffusion Into Metallic Material Surfaces (AREA)
- Basic Packing Technique (AREA)
Abstract
The present invention relates on steelwork or form the method for the nitride layer that the degree of depth is evenly arranged in the steelwork.Steelwork is fluoridized in the gas mixture atmosphere of fluorine and rare gas element composition under heating condition, carries out nitrogenize in nitrogenize gas atmosphere then under heating condition.
Description
The present invention relates to the nitrogen surface hardening nitriding method of steel, this method comprises the special processing that steelwork is helped producing darker and uniform nitride layer or nitrided surface.
For improving wear resistance, solidity to corrosion and the physical strength such as fatigue strength of steel, generally be on the surface of steel, to form one deck nitride layer or nitrided surface.Typical technology is nitrogenize (gas nitriding, a gas soft nitriding) method of taking the mixture of ammonia or ammonia and carbonaceous sources gas (RX gas) separately.These class methods are in-problem on the stability of method, because when handling the steel alloy product or the steelwork of complex configuration is arranged, resulting nitrogenize appearance is tending towards can not be smooth.
Steelwork generally is to carry out nitrogenize being not less than under 500 ℃ the temperature, and this moment, the nitrogen on steel surface absorbed or the nitrogen diffusion not only requires there is not organic or inorganic thing spot, and required No oxided film.Moreover also must there be high activity on the surface of steel itself.But in fact be impossible stop the formation of oxide film and obtain complete activated steel surface in this nitridation process, with formula stainless steel product difficult to understand is example, before nitriding furnace that it is packed into normally with hydrofluoric acid-nitric acid to remove passivation film from its surface, but will remove passivation film fully is the comparison difficulty, and the upper layer that activate steel fully also is impossible.Therefore, almost there is not possibility to form satisfied nitrogenize skin.And before nitrogenize, remove the organic or inorganic spot generally with deoil stain or make organic washing of alkali with for example trieline.But nearest antipollution detailed rules and regulations regulation (destruction of control ozonosphere) can not be used the most effective used so far purging method-organic washing, and this also is a major obstacle that forms satisfied nitrogenize appearance.
In the case, the present inventor once had discovery, promptly carried out before the steelwork nitrogenize as NF
3Fluoro-gas shelter with heating condition under fluoridize, carry out nitrogenize again, the then cleaning on steel surface (remove organic and inorganic spot and remove oxide film) and the activation just can realize.And obtain satisfied nitrogenize appearance, this technology Japan and U. S. application patent (Japanese patent application No. 1-177660 and Application No. 479,013, applying date 1990.2.12).In the method, the steelwork morals in stove, heat and with as NF
3And so on gas contact carry out pre-treatment.The result; the activation fluorine atom has destroyed and has sticked to the steel surface that the lip-deep organic and inorganic spot composition of steel has obtained cleaning; the lip-deep passive film of steel (comprising oxide film) has been transformed into fluoride films simultaneously, covers and protecting the steel surface, after this again steelwork is carried out nitrogenize.In this nitriding process, above-mentioned fluoride films the heating under be introduced in the stove by the nitriding gas that contains nitrogenous source (as NH
3) and H
2The mixed gas of forming destroys.Particularly the destruction of said fluoride films and removing has stayed cleaning and activated steel surface, and the nitrogen-atoms rapid permeability in the nitriding gas and diffuse into cleaning, activated steel surface has formed evenly and dark nitrogenize appearance.But, although NF
3Gas has above-mentioned needed performance, and its shortcoming is the expense height, moreover fluoridizing of will being fit to needs quite high temperature (280-500 ℃), and sizable energy expenditure is promptly arranged, and this has just increased processing costs.
After above-mentioned situation carried out research, as its purpose, this method can form all even darker nitrogenize appearance with nitriding method that a kind of steel is provided in the present invention, and expense is lower.
For achieving the above object, one aspect of the present invention is characterized in that fluoridizing steelwork under the fluoro-noble gas mixtures is sheltered under heating condition at a kind of nitriding method of steel, shelters the same product of nitrogenize down in nitriding gas then under heating condition; Be nitriding method on the other hand, it is characterized in that under heating condition, under fluoro-nitrogen trifluoride-noble gas mixtures is sheltered, fluoridizing steelwork, under heating condition, shelter the same product of nitrogenize down then in nitriding gas at a kind of steel.
The present inventor uses NF for reducing
3Expense as the nitriding of fluorinated gas had once been carried out a series of research, before finding at above-mentioned employing NF
3Think in the conceptual phase as the basic invention of fluorinated gas and be not suitable for fluorizated fluorine (F
2) in fact the fabulous activity of fluoridizing is arranged, and fluorine can be than NF
3Finish under the much lower temperature and fluoridize.The present invention just is based on above-mentioned discovery.
Therefore, first invention of the application is at adopting F
2With as N
2And so on the flaorination process of mixture of rare gas element.Use this technology, at about 150-300 ℃, preferably about 200-250 ℃ low relatively temperature range just can be finished substantially and fluoridize.Second invention relates to employing by N
2, F
2And NF
3The blended flaorination process of forming.The latter process can use NF in being lower than prior art technology
3As the temperature range that fluorinated gas requires, promptly about 200-400 ℃, finish under preferably about 250-300 ℃ temperature and fluoridize, though this temperature range is a little more than aforementioned process using N
2And F
2The mixture of forming is as the desired temperature range of fluorinated gas.Therefore, find using F separately
2(F
2+ N
2) and use NF separately
3(NF
3+ N
2) time fluoridize high temperature head to 100-150 ℃ arranged between the temperature.Should be known in fluoridizing among the present invention, if necessary, can under the temperature outside the above-mentioned temperature range, carry out that for example the highest employing is about 500 ℃.Available F
2Be not only the general F that fusion electrolysis method or similar approach form
2, also available fluorochemicals such as BF
3, CF
4, HF, SF
6, C
2F
6, WF
6, CHF
3, SiF
4In cracking plant, carry out the F that thermo-cracking forms
2(gas).The F of Shi Yonging in the present invention
2Comprise the F that produces by thermo-cracking
2
Below the present invention is given a detailed account.
According to the present invention, above-mentioned employing (1) N that fluoridizes
2+ F
2Mixed gas or (2) N
2+ F
2+ NF
3Mixed gas.
Under the situation of (1), N
2+ F
2Be binary mixture, F
2Concentration be set at 0.05 to 20%(volume, down with)＞.Use F
2Shortcoming be, under high density, fluoridize restive because F
2Be highly active; F when the lower concentration that is no more than 1%
2Though be easy to control,, need the processing of long period for enough case-hardened steel is arranged.Therefore, preferred F
2Concentration is 3-10%.Under the situation of (2), use F
2+ NF
3+ N
2Mixed gas, preferred F
2Concentration is 1-5%, preferred NF
3Concentration is 1-20%.Using F
2+ NF
3+ N
2During tertiary mixture, F
2And NF
3Ratio be decided by the time of fluoridizing and the temperature of being scheduled to.Therefore, because the time of fluoridizing of length means long working hour, F in the ternary gas mixture
2/ NF
3Than considering that the price of this situation and fluorinated gas decides.
The end of the present invention ladle is drawn together all kinds of steel, and as carbon steel, stainless steel etc., these steel are not limited to shape, can be tabular or round or very to cause be the machining shape of a screw or other.The end of the present invention steel also is not limited to said those steel, also comprises the alloy of said steel and based on said steel and the alloy that replenishes with other metals.
According to the present invention, end steel is handled by two kinds of methods: (A) carry out fluoridation with the first heat treated stove, handle stove with second then and carry out nitrogenize; Or (B) in having the same heat treated stove of fluoridizing chamber and nitrogenize chamber, handle.
If fluoridize the end steel processing of carrying out nitrogenize with the heat treated stove with the heat treated stove of (a), its method comprises the steps: first, in said heat treated stove, fluoridize as follows: place the first heat treated stove to be heated to 150-300 ℃ the case-hardened steelwork of desire, preferably 200-250 ℃; Under similarity condition with fluorine (F
2+ N
2) introduce the heat treated stove and steelwork was remained in said fluorine gas under the above-mentioned uniform temp about 10-120 minute, preferably about 20-90 minute, or for obtaining the about 30-60 of better effect minute.If use by such as BF
3And so on the F that produces of compound cracking
2, just need or place process furnace contiguous at the preposition cracker of process furnace.Formed F after the above-claimed cpd thermo-cracking
2With N
2Mix, mixture is imported process furnace.Be transformed into fluoride films by the lip-deep passive film of this step steel (mainly forming) by oxide compound.This reaction for example is to be undertaken by following reactional equation:
Above-mentioned processing is carried out with the heat treated stove respectively, for example the heat treated stove described in Fig. 1.
In the accompanying drawings, code name 1 expression bell housing, 2 expression tubular inner casings are within the shell; Integral body be placed in shell 1 the top be a skeleton construction 10, have coupling device 10 α and be connected with suspension hook with crane etc.; What integral body was placed in inner casing 2 tops is a shape structure 11, has coupling device 11 α and is connected with the suspension hook with crane etc.; In 2 li formation of inner casing is to fluoridize chamber, space configuration one heating chamber between shell 1 and the shell 2.The steelwork that code name 3 representatives are packed shell 2 into and taken out from shell 2.Steelwork 3 places on the platform 15 of centre hole 14, and respectively there is a centre hole in the space between the second tubular wire netting, 17 α that stretch upwards at the first tubular wire netting 16 that stretches upwards from centre hole 14 with around the platform by the porous separation scraper 17b(that inserts) merotomize, the hole of the install combustion device that code name 4 representatives form on all walls in shell 1 bottom, 4 α represent the discharge outlet on shell 1 crown wall, 5 are substrate, 6 for making furnace atmosphere round-robin fan, the centre hole 14 of alignment stage 15 belongs to net 16 from making the furnace atmosphere circulation by centre hole 14 and tubular metal.7 is heat exchanger, places the centre of pipe 7 α that stretch from the substrate of said inner casing downwards.8 for forcing the refrigeration cycle gas blower, places the pipe 7 α downstreams of heat exchanger 7.9 for introducing fluorine gas in the conduit of inner casing 2.12 α are from inner casing 2 discharging waste gas pipelines, are divided into two the tunnel in the middle, i.e. arm 17 and 19,17 mounted valves, 18,19 mounted valves 20 and vacuum pump 21.When the exhaust gas pressure in the inner casing 2 is high, use tap line 17; When exhaust gas pressure is low, use tap line 19 to vacuumize with the suction of vacuum pump, 12 for being connected in the anti-pollution device of said waste pipe 12 α ends, this anti-pollution device comprises-to horizontal activated carbon column 22, every post has heater coil 23 to twine outward and a fin-shaped heat exchanger 24, and its function is to make the waste gas that imports activated carbon column 22 by residual F
2Be transformed into harmless CF Deng thermal response with gac
4, and enter fin-shaped heat exchanger 24 and cool off.13 is one to be installed on the cleanser on the pipe 25 of extending from said heat exchanger 24, be filled with water in the cleanser, its function be will pipe 25 waste gas (HF is F in the inner casing 2 by making HF be partially dissolved in water with bubble form
2With H
2O and H
2The by product of reaction).
When using this heat treatment furnace, fluoridize as follows and carry out: connect 10 α and 11 α sling said shell 1 and inner casing 2 with crane hook (not shown), end steel 3 is placed on the platform 15, put down inner casing 2 and shell 1 to original position (being shown in Fig. 1), to place the flame heat regulating radiation of the burner (not shown) of burner port 4 to go in the heating chamber that forms between shell 1 and the inner casing 2 then, the steelwork 3 in the inner casing 2 is heated thus.Then will be such as NF
3Deng fluoro-gas introduce inner casings 2 and fluoridize from its bottom by managing 9, the time of fluoridizing is about 30-60 minute, as above addresses.
Its nitrogenize is to be undertaken by following step: because the steelwork 3 after fluoridation is covered by fluoride films, even be exposed to and also can be kept perfectly in the atmosphere and do not have the surface oxidation effect, steelwork under this condition can be stored, also can carry out nitrogenize at once in said second process furnace, second process furnace that carries out nitrogenize structurally is similar to the first above-mentioned process furnace.Method is that the inner casing 2 of the second process furnace A ' and shell 1 are sling, steelwork 3 is stacked on the platform, again inner casing 2 and shell 1 are put back to original position, then the flame heat regulating radiation of burner is gone into the steelwork that under 480-700 ℃ nitriding temperature, heats in the space between inner casing 2 and the shell 1 in the inner casing 2.This moment is with NH
3Or by NH
3Keep with this understanding about 120 minutes from the pipe 9 introducing stoves of process furnace bottom branchs and with steelwork with the gaseous mixture of carbonaceous sources or longer, in this method, said fluoride films is by H
2Or reduction of water (by product of nitrogenizing reaction) in a small amount or destruction, its reaction for example can be undertaken by following reactional equation, to obtain activated steel surface.
About the removal of fluoride films, can before introducing nitriding gas, introduce N
2And H
2Gas mixture or H
2Gas is film destruction, and the selection of this method trouble that can avoid the by product Neutral ammonium fluoride to be brought.
On formed activated steel surface, by the active nitrogen effect of nitriding gas deutero-and infiltrate and diffuse into steelwork.As a result, by the surface of steelwork to its inside, form uniform nitrogenate (as CrN, Fe
2N, Fe
3N and Fe
4N) superhard compound layer (nitride layer) and enough degree of depth are arranged is thereafter that the hard diffusion layer of N atom is formed, and above-claimed cpd layer and diffusion layer constitute whole nitrogenize appearance.
Fluoridizing in single heat treatment furnace (B) under the situation with nitrogenize, is the process furnace that adopts Fig. 2 structure for example.Among the figure, 1 ' represent process furnace, 2 ' represent the wire basket of splendid attire metallic article (not shown), 3 ' represent well heater, 5 ' represent the waste discharge tracheae, 6 ' be insulating wall, 7 ' be fire door, 8 ' be fan, 10 ' be pillar stiffener, 12 ' be vacuum pump, 13 ' be emission-control equipment, 21 ' for the body of heater of insulating wall is arranged, its inside by divider wall or luffer boards 22 ' be divided into chamber 23 ' and 24 ', divider wall can freely open and close, divider wall 22 ' make chamber 23 ' with 24 ' maintenance is airtight and to thermal isolation, the keying (as figure) of can sliding vertically, the chamber is fluoridized in 23 ' representative, 24 ' represent the nitrogenize chamber, 23 ' and 24 ' respectively have one support wire basket 2 ' matrix 25 ', 25 ' form by pair of tracks, its arrangement can make wire basket 2 ' along track optionally slip into fluoridize chamber 23 ' or nitrogenize chamber 24 '.26 ' for fluorinated gas is imported fluoridize chamber 23 ' gas inlet tube, 27 ' be temperature sensor.Fluoridize the lid 7 that 23 ' the place ahead, chamber drives with horizontal direction ' releasably cover.28 ' for nitriding gas introduce nitrogenize chamber 24 ' the nitriding gas pipe.
In above-mentioned process furnace, nitrogenize is undertaken by following step: at first will fill the basket 2 of steelwork ' place fluoridize chamber 23 ', raise fluoridize chamber 23 ' internal temperature steelwork is heated to 150-300 ℃, with this understanding with fluoro-gas (F
2+ N
2) introduce in the chamber and fluoridized 30 to 60 minutes.Fluoridize and to fluoridize chamber 23 ' ventilation gas of draining after finishing.
Then, carry out nitrogenize as follows: above-mentioned divider wall is opened, with steelwork and wire basket 2 ' be transferred to together as a whole nitrogenize chamber 24 ', close divider wall, the nitrogenize chamber 24 that raises this moment ' interior temperature to 480-600 ℃ with the heating steelwork and with H
2Introduce the nitrogenize chamber and kept 1 hour, the fluoride films that covers the steel surface is destroyed and the matrix surface exposure product.Then, with nitriding gas, promptly by NH
3, N
2, H
2, CO and CO
2The mixed gas introducing nitrogenize chamber of forming 24 ' under this temperature, carried out nitrogenize 4-5 hour.After this, room temp is reduced to 350-450 ℃, introduce by H with this understanding
2And N
2The gas mixture of forming or by N
2, H
2And CO
2The gas mixture of forming cleaned 1 hour, after this, with nitrogenize chamber 24 ' in exhaust gas emission fall and open divider wall 22 '.Then with steelwork and wire basket 2 ' as a global transfer to fluoridize chamber 23 ' and close divider wall 22 ', then under this condition, cool off.Cooling be by gas inlet tube 26 ' with nitrogen introduce fluoridize chamber 23 '.So the steelwork of handling has darker or uniform nitrogenize appearance.Steelwork fluoridize heating can nitrogenize chamber 24 ' in carry out, soon steelwork directly places the nitrogenize chamber and heats, open divider wall 22 ' then and transfer to and fluoridize chamber 23 ' fluoridize, after this again steelwork is put back to nitrogenize chamber 24 ' carry out nitrogenize steelwork.In this case, nitrogenize chamber 24 ' preheating be that heat when utilizing steelwork to fluoridize is finished.
Therefore, according to the present invention, destroyed the steel surface highly activation that can expose behind the fluoride films, nitrogen-atoms acts on and has formed the big and uniform superhard nitride layer of the degree of depth on this activatory surface.Moreover the used gas of nitrogenize is the mixed gas based on fluorine, with use NF
3Compare, not only cheap, also allow use lower fluoridize temperature, thereby in fact processing costs has fallen at the end.
Fig. 1 of the present invention is the sectional view that is used for heat treatment furnace one example of the present invention, and Fig. 2 is the sketch of another process furnace.
Now the embodiment of the invention is described below:
At first the example of double furnace is used in narration
Example 1
Fluoridize
Make some Ovshinsky CARBURIZING FURNACE FOR STAINLESS FASTENER nails (sample), with the washing of trifluoro-ethylene steam.Screw is put into first process furnace (Fig. 1), press preceding method 200 ℃ of fully heating down, then with this understanding, will be by 10%F
2And N
2The gas mixture of forming is introduced in the stove, and speed is the internal volume of 5 times of stoves of time per unit, and product kept 60 minutes therein, took out some samples then, checked the upper layer of each sample, and conclusive evidence has formed fluoride films on whole surface.
Nitrogenize
Sample transfer to the second process furnace A ' that will cross through above-mentioned fluoridation imports NH in stove
3+ 50%RX gas was in 530 ℃ of following nitrogenize 6 hours, and after disposing, sample takes out through air cooling and from stove.The Ovshinsky CARBURIZING FURNACE FOR STAINLESS FASTENER nail that above-mentioned steps provides with the nitrogen surface hardening.
Comparison example 1
Divided by N
2+ NF
3(concentration: 1%) gas mixture replaces fluoridizing gas and with 410 ℃ fluoridize outside the temperature, repeats example 1 described step, obtains the case-hardened Ovshinsky CARBURIZING FURNACE FOR STAINLESS FASTENER of nitrogen and follows closely.
Hardness, condition and the thickness of the outside the pale of civilization table of product nitrogen of example 1 and comparison example 1 are compared, found that the identical in quality of the two product.Contrast is got up, the product expense of example 1 be comparison example 1 the product expense 1/3rd.
Example 2
Fluoridize
Make some motor car engine sniff valves (sample), it is directly placed process furnace A and temperature is risen to 280 ℃, import N with this understanding
2+ 10%F
2+ 8%NF
3The mixed gas of forming, speed is 10 times of furnace volumes of time per unit, product kept in stove 30 minutes.After this, take out some samples, check the upper layer of each sample.Result's conclusive evidence, whole surface has formed fluorinated layer.
Nitrogenize
With above-mentioned through fluoridation sample transfer to the second process furnace A ' and be heated to 570 ℃.Introduce NH in the case
3+ 50%RX nitriding gas 120 minutes.After this sample takes out with air cooling and in stove.
Comparison example 2
Use NF
3(1%)+N
2Sheltering gas is heated to 380 ℃ and fluoridizes engine sniff valve sample is provided under the condition identical with example 2.
The product of the product of example 2 and comparison example 2 identical in quality fluoridized in the expense of engine sniff valve product in the ratio comparison example 2 that gas expense accounts for and uses NF
3The product that obtains low 40%.And the heating and cooling time of fluorination step can reduce 75 minutes.
Be to use the example of same heat treated stove (B) below
Example 3
Fluoridizing with nitrogenize is to carry out with having the same heat treated stove (Fig. 2) of fluoridizing chamber and nitrogenize chamber.Handle respectively with the described method of specification sheets text, the condition of each processing such as example 1 obtain the result identical with example 1.
Example 4
Fluoridize and nitrogenize with having the heat treatment furnace (Fig. 2) of fluoridizing chamber and nitrogenize chamber, the described method of by specification text is handled respectively, and the condition of each processing is identical with example 2, obtains the result identical with example 2.
State as preceding, adopt mixture based on the fluorine of cheapness to carry out fluorizated the inventive method and can reduce the required expense of handling greatly, and can be than using NF because fluoridize
3Fluoridize under the temperature of hanging down 100-150 ℃ and carry out, reduced the heat energy of demand, this also reduces expense significantly.Particularly because fluoridize and can carry out under a kind of so low relatively temperature, also can shorten the cooling time after fluoridizing, and whole process of production just can be accelerated.Moreover fluorine has the intensive smell, compares NF
3Easier leak detection more can guarantee to prevent and deleterious F
2The pollution problem that interrelates.In addition, fluorizated low temperature is good under the situation with same heat treatment furnace (continuous oven) of fluoridizing chamber and nitrogenize chamber in design, and for example, prolonged the duration of service of fluoridizing the divider wall sealing material between chamber and the nitrogenize chamber; Because fluoridizing used fluorine is highly corrosive, but when fluoridizing temperature when low, the aging structure of sealing material character is more unconspicuous, so can realize long material lifetime, other advantage is simplification and the life-time dilatation that strengthens structure and other structural elements.
Claims (2)
1, a kind of nitriding method of steel is characterized in that steelwork fluoridizes in the mixed-gas atmosphere that fluorine and rare gas element are formed under heating condition, carry out nitrogenize then in the atmosphere of nitriding gas under heating condition.
2, a kind of nitriding method of steel is characterized in that steelwork fluoridizes nitrogenize in the atmosphere of nitrogenize gas under heating condition then under heating condition in the mixed-gas atmosphere that fluorine, nitrogen trifluoride and rare gas element are formed.
Priority Applications (6)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP91305033A EP0516899B1 (en) | 1991-06-04 | 1991-06-04 | Method of nitriding steel |
| DE69113789T DE69113789T2 (en) | 1991-06-04 | 1991-06-04 | Process of nitriding steel. |
| DK91305033.2T DK0516899T3 (en) | 1991-06-04 | 1991-06-04 | Method of Nitrating Steel |
| AT91305033T ATE129023T1 (en) | 1991-06-04 | 1991-06-04 | METHOD OF NITRIDATION OF STEEL. |
| ES91305033T ES2082138T3 (en) | 1991-06-04 | 1991-06-04 | METHOD OF NITRURATION OF STEEL. |
| CN91104154.0A CN1032375C (en) | 1991-06-04 | 1991-06-24 | Steel nitriding method |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP91305033A EP0516899B1 (en) | 1991-06-04 | 1991-06-04 | Method of nitriding steel |
| CN91104154.0A CN1032375C (en) | 1991-06-04 | 1991-06-24 | Steel nitriding method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1067929A true CN1067929A (en) | 1993-01-13 |
| CN1032375C CN1032375C (en) | 1996-07-24 |
Family
ID=36781525
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN91104154.0A Expired - Lifetime CN1032375C (en) | 1991-06-04 | 1991-06-24 | Steel nitriding method |
Country Status (6)
| Country | Link |
|---|---|
| EP (1) | EP0516899B1 (en) |
| CN (1) | CN1032375C (en) |
| AT (1) | ATE129023T1 (en) |
| DE (1) | DE69113789T2 (en) |
| DK (1) | DK0516899T3 (en) |
| ES (1) | ES2082138T3 (en) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1106454C (en) * | 1995-05-25 | 2003-04-23 | 空气及水株式会社 | Nitrizing for steel |
| CN100460552C (en) * | 2002-09-24 | 2009-02-11 | 本田技研工业株式会社 | Method of nitriding metal ring and apparatus therefor |
| CN102517540A (en) * | 2011-12-20 | 2012-06-27 | 广东华南特种气体研究所有限公司 | Passivation method of excimer laser gas configuration device |
| CN107109615A (en) * | 2014-07-31 | 2017-08-29 | 世伟洛克公司 | The enhancing activation of self-passivating metal |
| CN111843407A (en) * | 2020-07-29 | 2020-10-30 | 扬州大学 | Nitriding device and nitriding processing method for 304 stainless steel spiral reamer |
| US11649538B2 (en) | 2018-06-11 | 2023-05-16 | Swagelok Company | Chemical activation of self-passivating metals |
| US11885027B2 (en) | 2020-04-29 | 2024-01-30 | Swagelok Company | Activation of self-passivating metals using reagent coatings for low temperature nitrocarburization |
| US12129556B2 (en) | 2019-12-06 | 2024-10-29 | Swagelok Company | Chemical activation of self-passivating metals |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2731232B1 (en) * | 1995-03-01 | 1997-05-16 | Stephanois Rech | PROCESS FOR TREATING FERROUS SURFACES SUBJECT TO HIGH FRICTION STRESS |
| JPH102336A (en) * | 1996-04-16 | 1998-01-06 | Koyo Seiko Co Ltd | Retainer for bearing and manufacture therefor |
| JP3699803B2 (en) * | 1997-05-09 | 2005-09-28 | 光洋精工株式会社 | Manufacturing method of bearing and bearing |
| DE102016221891A1 (en) * | 2016-11-08 | 2018-05-09 | Robert Bosch Gmbh | Process for the heat treatment of a high-alloy steel workpiece |
| EP3684961B1 (en) | 2017-09-19 | 2022-11-02 | BorTec GmbH | Improved pre-treatment process of a surface of a metallic substrate |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2851387A (en) * | 1957-05-08 | 1958-09-09 | Chapman Valve Mfg Co | Method of depassifying high chromium steels prior to nitriding |
| SU638635A1 (en) * | 1977-05-24 | 1978-12-28 | Московский Автомобильно-Дорожный Институт | Method of nitriding steel components |
| EP0352061B1 (en) * | 1988-07-20 | 1994-09-21 | Hashimoto Chemical Industries Co., Ltd. | Metal material with film passivated by fluorination and apparatus composed of the metal material |
| EP0408168B1 (en) * | 1989-07-10 | 1994-06-08 | Daidousanso Co., Ltd. | Method of pretreating metallic works and method of nitriding steel |
| US5112030A (en) * | 1990-10-01 | 1992-05-12 | Daidousanso Co., Ltd. | Heat treat furnace for fluorinating steel material |
-
1991
- 1991-06-04 DK DK91305033.2T patent/DK0516899T3/en active
- 1991-06-04 AT AT91305033T patent/ATE129023T1/en not_active IP Right Cessation
- 1991-06-04 DE DE69113789T patent/DE69113789T2/en not_active Expired - Lifetime
- 1991-06-04 ES ES91305033T patent/ES2082138T3/en not_active Expired - Lifetime
- 1991-06-04 EP EP91305033A patent/EP0516899B1/en not_active Expired - Lifetime
- 1991-06-24 CN CN91104154.0A patent/CN1032375C/en not_active Expired - Lifetime
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1106454C (en) * | 1995-05-25 | 2003-04-23 | 空气及水株式会社 | Nitrizing for steel |
| CN100460552C (en) * | 2002-09-24 | 2009-02-11 | 本田技研工业株式会社 | Method of nitriding metal ring and apparatus therefor |
| CN102517540A (en) * | 2011-12-20 | 2012-06-27 | 广东华南特种气体研究所有限公司 | Passivation method of excimer laser gas configuration device |
| US11473183B2 (en) | 2014-07-31 | 2022-10-18 | Swagelok Company | Enhanced activation of self-passivating metals |
| US10214805B2 (en) | 2014-07-31 | 2019-02-26 | Swagelok Company | Enhanced activation of self-passivating metals |
| US10604832B2 (en) | 2014-07-31 | 2020-03-31 | Swagelok Company | Enhanced activation of self-passivating metals |
| CN107109615B (en) * | 2014-07-31 | 2020-12-04 | 世伟洛克公司 | Enhanced activation of self-passivating metals |
| CN107109615A (en) * | 2014-07-31 | 2017-08-29 | 世伟洛克公司 | The enhancing activation of self-passivating metal |
| US11649538B2 (en) | 2018-06-11 | 2023-05-16 | Swagelok Company | Chemical activation of self-passivating metals |
| US12129556B2 (en) | 2019-12-06 | 2024-10-29 | Swagelok Company | Chemical activation of self-passivating metals |
| US11885027B2 (en) | 2020-04-29 | 2024-01-30 | Swagelok Company | Activation of self-passivating metals using reagent coatings for low temperature nitrocarburization |
| CN111843407A (en) * | 2020-07-29 | 2020-10-30 | 扬州大学 | Nitriding device and nitriding processing method for 304 stainless steel spiral reamer |
| CN111843407B (en) * | 2020-07-29 | 2021-11-02 | 扬州大学 | A 304 stainless steel spiral reamer nitriding device and nitriding processing method |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1032375C (en) | 1996-07-24 |
| ES2082138T3 (en) | 1996-03-16 |
| DE69113789D1 (en) | 1995-11-16 |
| DK0516899T3 (en) | 1996-02-26 |
| EP0516899B1 (en) | 1995-10-11 |
| ATE129023T1 (en) | 1995-10-15 |
| EP0516899A1 (en) | 1992-12-09 |
| DE69113789T2 (en) | 1996-04-25 |
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