CN111663097A - Austenitic nitriding process - Google Patents
Austenitic nitriding process Download PDFInfo
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- CN111663097A CN111663097A CN202010555438.1A CN202010555438A CN111663097A CN 111663097 A CN111663097 A CN 111663097A CN 202010555438 A CN202010555438 A CN 202010555438A CN 111663097 A CN111663097 A CN 111663097A
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- nitriding
- treatment
- furnace
- ammonia
- austenitic
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- 238000005121 nitriding Methods 0.000 title claims abstract description 66
- 238000000034 method Methods 0.000 title claims abstract description 25
- 230000008569 process Effects 0.000 title claims abstract description 21
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims abstract description 45
- NLXLAEXVIDQMFP-UHFFFAOYSA-N Ammonia chloride Chemical compound [NH4+].[Cl-] NLXLAEXVIDQMFP-UHFFFAOYSA-N 0.000 claims abstract description 18
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 16
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 14
- 238000005202 decontamination Methods 0.000 claims abstract description 11
- 230000003588 decontaminative effect Effects 0.000 claims abstract description 11
- 239000006004 Quartz sand Substances 0.000 claims abstract description 10
- 235000019270 ammonium chloride Nutrition 0.000 claims abstract description 9
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 8
- 238000009713 electroplating Methods 0.000 claims abstract description 7
- 239000011248 coating agent Substances 0.000 claims abstract description 6
- 238000000576 coating method Methods 0.000 claims abstract description 6
- 239000007787 solid Substances 0.000 claims abstract description 5
- 238000007664 blowing Methods 0.000 claims abstract description 4
- 238000001816 cooling Methods 0.000 claims abstract description 4
- 239000004576 sand Substances 0.000 claims abstract description 4
- 229910021529 ammonia Inorganic materials 0.000 claims description 15
- 239000011521 glass Substances 0.000 claims description 8
- 238000010438 heat treatment Methods 0.000 claims description 8
- 150000003839 salts Chemical class 0.000 claims description 8
- 238000004321 preservation Methods 0.000 claims description 7
- 239000000428 dust Substances 0.000 claims description 6
- 239000000203 mixture Substances 0.000 claims description 6
- 238000007789 sealing Methods 0.000 claims description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 3
- 229920000742 Cotton Polymers 0.000 claims description 3
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 3
- 238000000354 decomposition reaction Methods 0.000 claims description 3
- 239000004744 fabric Substances 0.000 claims description 3
- 235000019353 potassium silicate Nutrition 0.000 claims description 3
- 239000000779 smoke Substances 0.000 claims description 3
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 claims description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 3
- 229910001566 austenite Inorganic materials 0.000 abstract description 3
- 238000002161 passivation Methods 0.000 abstract 1
- 229910000963 austenitic stainless steel Inorganic materials 0.000 description 5
- 230000009471 action Effects 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000002349 favourable effect Effects 0.000 description 2
- 239000003973 paint Substances 0.000 description 2
- 238000004140 cleaning Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 238000004904 shortening 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
- C23C8/06—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 invention discloses an austenite nitriding process, which comprises the following steps: step one, decontamination treatment; step two, seepage-proofing treatment; step three, secondary decontamination; step four, exhausting and nitriding; step five, cooling; in the first step, the part is subjected to dry sand blowing treatment on the surface of the part by using 100-200-mesh quartz sand and compressed air; in the second step, the non-nitriding part of the part treated in the first step is subjected to anti-seepage nitrogen treatment by using electroplating or coating; according to the invention, the secondary decontamination treatment is carried out on the surface of the part, so that the removal of residual stains on the surface of the part is facilitated, the nitriding treatment is further facilitated, the leakage condition of ammonia gas is detected timely by detecting the ammonia gas regularly, the occurrence of dangerous accidents is avoided, meanwhile, the removal of a passivation film on the surface of the part is facilitated by using the placed solid ammonium chloride, the nitriding treatment of the part is facilitated, the nitriding treatment time is shortened, and the working efficiency is improved.
Description
Technical Field
The invention relates to the technical field of austenite nitriding, in particular to a process for austenite nitriding.
Background
Austenitic stainless steel, mean have austenitic stainless steel of tissue at room temperature, because austenitic stainless steel has comprehensive and good comprehensive properties, have obtained the extensive application in every trade, wherein need to carry on the nitriding treatment to austenitic stainless steel in the course of making austenitic stainless steel often, but the grain succession of the traditional nitriding treatment is unfavorable to making the dirt of the surface of the part totally clear up, thus unfavorable to the nitriding treatment to the part, and unfavorable to checking the gas leakage situation in the course of nitriding treatment, apt to cause the emergence of the dangerous accident, nitriding time is long at the same time, has reduced the working efficiency.
Disclosure of Invention
The object of the present invention is to provide a process for austenitic nitriding that solves the problems set forth in the background art mentioned above.
In order to solve the technical problems, the invention provides the following technical scheme: the austenitic nitriding process comprises the following steps: step one, decontamination treatment; step two, seepage-proofing treatment; step three, secondary decontamination; step four, exhausting and nitriding; step five, cooling;
in the first step, the part is subjected to dry sand blowing treatment on the surface of the part by using 100-200-mesh quartz sand and compressed air;
in the second step, the non-nitriding part of the part treated in the first step is subjected to anti-seepage nitrogen treatment by using electroplating or coating;
in the third step, the nitrided part of the part treated in the second step is wiped by using gasoline or alcohol on the surface of the part, the non-nitrided part is subjected to dust collection treatment by using a dust collector, and then the part is wiped clean by using cotton cloth;
in the fourth step, the part treated in the third step is placed in a nitriding furnace, a mixture of solid ammonium chloride and quartz sand is added into the nitriding furnace, the furnace cover is sealed and then can be heated, ammonia gas is introduced into the nitriding furnace in the heating process to discharge air remained in the nitriding furnace, the air in the nitriding furnace needs to be completely discharged before the nitriding furnace is heated to 150 ℃, Ph test paper soaked by water or a glass rod soaked with salt is used for checking the sealing conditions of the nitriding furnace and a pipeline every 20 minutes in the exhausting process, the ammonia gas is continuously introduced to ensure that the air pressure in the nitriding furnace reaches 200-400Pa, the heating temperature is 510-530 ℃, the heat is preserved for 15-20 hours, the decomposition rate of the ammonia is 60-65%, and the nitriding treatment is carried out 3 hours before the nitriding is finished;
in the fifth step, after the heat preservation in the fourth step is finished, the exhaust valve is closed, the ammonia flow is reduced, the heat preservation is carried out for 2 hours, the nitrogen concentration on the surface of the part is reduced, then the power is cut off and the temperature is reduced, a small amount of ammonia gas is continuously introduced into the furnace, the positive pressure is preserved in the furnace, the ammonia supply is stopped when the furnace temperature is cooled to 155 ℃ which is equal to the temperature of 145 and equal to the temperature of 155 ℃, and then the part is discharged from the furnace and is subjected to.
According to the technical scheme, in the step one, the pressure of the compressed air is 0.3-0.5 MPa.
According to the technical scheme, in the second step, the electroplating is tinning, and the coating is a mixture of water glass and graphite powder.
According to the technical scheme, in the fourth step, the ratio of the fixed ammonium chloride to the quartz sand is 1: 180.
according to the technical scheme, in the fourth step, the soaked Ph test paper turns blue when meeting ammonia, and the glass rod stained with salt is discharged with white smoke when meeting ammonia.
According to the technical scheme, in the fourth step, the nitrogen withdrawal temperature is 560-570 ℃.
Compared with the prior art, the invention has the following beneficial effects: according to the austenitic nitriding process, secondary decontamination treatment is carried out on the surface of the part, so that residual stains on the surface of the part can be removed, and nitriding treatment is further facilitated; meanwhile, the ammonia gas is periodically detected through the arranged soaked Ph test paper and the glass rod stained with salt, so that the ammonia gas leakage condition can be timely and visually detected, and dangerous accidents are avoided; and the placed solid ammonium chloride is beneficial to removing the passive film on the surface of the part in the process of nitriding the part, thereby shortening the nitriding treatment time and improving the working efficiency.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:
FIG. 1 is a process flow diagram of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1, the present invention provides a technical solution: the austenitic nitriding process comprises the following steps: step one, decontamination treatment; step two, seepage-proofing treatment; step three, secondary decontamination; step four, exhausting and nitriding; step five, cooling;
in the first step, the part is subjected to dry sand blowing treatment on the surface of the part by using 100-200-mesh quartz sand and compressed air, and the pressure of the compressed air is 0.3-0.5 MPa;
in the second step, electroplating or coating paint is used for carrying out anti-nitriding treatment on the non-nitriding part of the part treated in the first step, wherein the electroplating is tinning, and the paint is a mixture of water glass and graphite powder;
in the third step, the nitrided part of the part treated in the second step is wiped by using gasoline or alcohol on the surface of the part, the non-nitrided part is subjected to dust collection treatment by using a dust collector, and then the part is wiped clean by using cotton cloth;
in the fourth step, the part treated in the third step is placed in a nitriding furnace, a mixture of solid ammonium chloride and quartz sand is added into the nitriding furnace, and the ratio of the fixed ammonium chloride to the quartz sand is 1: 180, heating after sealing the furnace cover, introducing ammonia gas into the nitriding furnace to discharge air remained in the nitriding furnace in the heating process, completely discharging the air in the nitriding furnace before heating to 150 ℃, using a Ph test paper soaked by water or a glass rod soaked with salt to check the sealing conditions of the nitriding furnace and a pipeline every 20 minutes in the exhaust process, wherein the soaked Ph test paper turns blue when encountering ammonia gas, the glass rod soaked with salt is discharged when encountering ammonia gas with white smoke, continuously introducing ammonia gas to ensure that the air pressure in the nitriding furnace reaches 200-400Pa, the heating temperature is 510 nitriding-530 ℃, the heat preservation is 15-20 hours, the decomposition rate of the ammonia is 60-65%, and performing nitrogen-removing treatment 3 hours before nitriding is finished, and the nitrogen-removing temperature is 560-570 ℃;
in the fifth step, after the heat preservation in the fourth step is finished, the exhaust valve is closed, the ammonia flow is reduced, the heat preservation is carried out for 2 hours, the nitrogen concentration on the surface of the part is reduced, then the power is cut off and the temperature is reduced, a small amount of ammonia gas is continuously introduced into the furnace, the positive pressure is preserved in the furnace, the ammonia supply is stopped when the furnace temperature is cooled to 155 ℃ which is equal to the temperature of 145 and equal to the temperature of 155 ℃, and then the part is discharged from the furnace and is subjected to.
Based on the above, the method has the advantages that the secondary decontamination treatment is carried out on the part before the nitriding treatment, so that the surface cleaning of the part is facilitated, the surface residue and the stain of the part are avoided, and the nitriding treatment of the part is not facilitated; utilize the soaked Ph test paper that sets up and be stained with the glass stick of salt to carry out periodic detection to the ammonia simultaneously, be favorable to in time and audio-visually detect out the emergence that the condition of revealing of ammonia has avoided dangerous accident, utilize the fixed ammonium chloride that sets up to be favorable to getting rid of the passive film that part surface formed simultaneously, avoided the part surface to remain there is the passive film to be unfavorable for carrying out the nitriding treatment to the part to work efficiency has been improved.
It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that changes may be made in the embodiments and/or equivalents thereof without departing from the spirit and scope of the invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (6)
1. The austenitic nitriding process comprises the following steps: step one, decontamination treatment; step two, seepage-proofing treatment; step three, secondary decontamination; step four, exhausting and nitriding; step five, cooling; the method is characterized in that:
in the first step, the part is subjected to dry sand blowing treatment on the surface of the part by using 100-200-mesh quartz sand and compressed air;
in the second step, the non-nitriding part of the part treated in the first step is subjected to anti-seepage nitrogen treatment by using electroplating or coating;
in the third step, the nitrided part of the part treated in the second step is wiped by using gasoline or alcohol on the surface of the part, the non-nitrided part is subjected to dust collection treatment by using a dust collector, and then the part is wiped clean by using cotton cloth;
in the fourth step, the part treated in the third step is placed in a nitriding furnace, a mixture of solid ammonium chloride and quartz sand is added into the nitriding furnace, the furnace cover is sealed and then can be heated, ammonia gas is introduced into the nitriding furnace in the heating process to discharge air remained in the nitriding furnace, the air in the nitriding furnace needs to be completely discharged before the nitriding furnace is heated to 150 ℃, Ph test paper soaked by water or a glass rod soaked with salt is used for checking the sealing conditions of the nitriding furnace and a pipeline every 20 minutes in the exhausting process, the ammonia gas is continuously introduced to ensure that the air pressure in the nitriding furnace reaches 200-400Pa, the heating temperature is 510-530 ℃, the heat is preserved for 15-20 hours, the decomposition rate of the ammonia is 60-65%, and the nitriding treatment is carried out 3 hours before the nitriding is finished;
in the fifth step, after the heat preservation in the fourth step is finished, the exhaust valve is closed, the ammonia flow is reduced, the heat preservation is carried out for 2 hours, the nitrogen concentration on the surface of the part is reduced, then the power is cut off and the temperature is reduced, a small amount of ammonia gas is continuously introduced into the furnace, the positive pressure is preserved in the furnace, the ammonia supply is stopped when the furnace temperature is cooled to 155 ℃ which is equal to the temperature of 145 and equal to the temperature of 155 ℃, and then the part is discharged from the furnace and is subjected to.
2. The process of austenitic nitriding according to claim 1, characterized in that: in the first step, the pressure of the compressed air is 0.3-0.5 MPa.
3. The process of austenitic nitriding according to claim 1, characterized in that: in the second step, the electroplating is tinning, and the coating is a mixture of water glass and graphite powder.
4. The process of austenitic nitriding according to claim 1, characterized in that: in the fourth step, the ratio of the fixed ammonium chloride to the quartz sand is 1: 180.
5. the process of austenitic nitriding according to claim 1, characterized in that: in the fourth step, the soaked Ph test paper turns blue when meeting ammonia, and white smoke is discharged when the glass rod stained with salt meets ammonia.
6. The process of austenitic nitriding according to claim 1, characterized in that: in the fourth step, the nitrogen withdrawal temperature is 560-570 ℃.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010555438.1A CN111663097A (en) | 2020-06-17 | 2020-06-17 | Austenitic nitriding process |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010555438.1A CN111663097A (en) | 2020-06-17 | 2020-06-17 | Austenitic nitriding process |
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| CN111663097A true CN111663097A (en) | 2020-09-15 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202010555438.1A Pending CN111663097A (en) | 2020-06-17 | 2020-06-17 | Austenitic nitriding process |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0652300A1 (en) * | 1993-10-05 | 1995-05-10 | Hans Prof. Dr.-Ing. Berns | Case nitriding for producing a high-strength austenitic skin in stainless steels |
| CN101649441A (en) * | 2008-08-12 | 2010-02-17 | 贵州红林机械有限公司 | Process method for nitriding austenitic stainless steel material |
| CN103014601A (en) * | 2012-12-09 | 2013-04-03 | 常州大学 | Austenitic stainless steel ion nitriding permeation catalyzing process |
| CN103215536A (en) * | 2012-01-20 | 2013-07-24 | 上海世传金属材料研发中心 | Low-temperature nitriding method for forming corrosion-resistant hardened layer on surface of stainless steel |
| CN109487202A (en) * | 2018-11-16 | 2019-03-19 | 中国航发西安动力控制科技有限公司 | For the nitridation process of stainless steel material |
-
2020
- 2020-06-17 CN CN202010555438.1A patent/CN111663097A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0652300A1 (en) * | 1993-10-05 | 1995-05-10 | Hans Prof. Dr.-Ing. Berns | Case nitriding for producing a high-strength austenitic skin in stainless steels |
| CN101649441A (en) * | 2008-08-12 | 2010-02-17 | 贵州红林机械有限公司 | Process method for nitriding austenitic stainless steel material |
| CN103215536A (en) * | 2012-01-20 | 2013-07-24 | 上海世传金属材料研发中心 | Low-temperature nitriding method for forming corrosion-resistant hardened layer on surface of stainless steel |
| CN103014601A (en) * | 2012-12-09 | 2013-04-03 | 常州大学 | Austenitic stainless steel ion nitriding permeation catalyzing process |
| CN109487202A (en) * | 2018-11-16 | 2019-03-19 | 中国航发西安动力控制科技有限公司 | For the nitridation process of stainless steel material |
Non-Patent Citations (1)
| Title |
|---|
| 李泉华: "《热处理实用技术》", 29 February 2000 * |
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