CN106435103A - Technological method for improving corrosion resistance of ferritic stainless steel - Google Patents
Technological method for improving corrosion resistance of ferritic stainless steel Download PDFInfo
- Publication number
- CN106435103A CN106435103A CN201610893444.1A CN201610893444A CN106435103A CN 106435103 A CN106435103 A CN 106435103A CN 201610893444 A CN201610893444 A CN 201610893444A CN 106435103 A CN106435103 A CN 106435103A
- Authority
- CN
- China
- Prior art keywords
- stainless steel
- ferritic stainless
- decay resistance
- ferritic
- improve
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/26—Methods of annealing
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D6/00—Heat treatment of ferrous alloys
- C21D6/002—Heat treatment of ferrous alloys containing Cr
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/26—Ferrous alloys, e.g. steel alloys containing chromium with niobium or tantalum
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/28—Ferrous alloys, e.g. steel alloys containing chromium with titanium or zirconium
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D2211/00—Microstructure comprising significant phases
- C21D2211/005—Ferrite
Abstract
The invention provides a technological method applied to the technical field of producing and processing ferritic stainless steel and used for improving corrosion resistance of the ferritic stainless steel. The technological method for improving the corrosion resistance of the ferritic stainless steel includes the steps of 1, heating raw materials of the ferritic stainless steel in heating equipment; 2, heating the raw materials to the annealing temperature of 800-900 DEG C; 3, maintaining the annealing temperature for 20-40 minutes; and 4, taking out the raw materials of the ferritic stainless steel for cooling the raw materials of the ferritic stainless steel and forming finished products of the ferritic stainless steel. According to the technological method for improving the corrosion resistance of the ferritic stainless steel, the steps are simple, there is no need to input excessive equipment and materials, the processing cost is low, the intercrystalline corrosion resistance of the ferritic stainless steel can be processed, intercrystalline corrosion of the ferritic stainless steel can be eliminated, the mechanical strength of the ferritic stainless steel can be improved, the problem that intercrystalline fracture occurs and the strength almost disappears completely when the ferritic stainless steel receives stress effect can be avoided, and therefore the performance of the ferritic stainless steel can be comprehensively and effectively improved, and the service life of the ferritic stainless steel can be prolonged.
Description
Technical field
The invention belongs to ferritic stainless steel production and processing technical field, more specifically, is to be related to a kind of raising ferrum element
The process of body rustless steel decay resistance.
Background technology
As China's nickel resources are deficienter, also, nickel resources price fluctuation amplitude is big in the world, and this significantly speeds up
The development of not nickeliferous ferritic stainless steel.Ferrite series stainless steel is mainly used in two big fields：Automobile exhaust system with
And washing machine drum.First, automobile exhaust system is used for a long time under high temperature and corrosive environment, can be big from ferritic stainless steel
Amplitude extends the life-span of automobile exhaust system parts.Second, washing machine drum is adding abluent moist environment for a long time
Under the conditions of use, under these conditions, absolutely not allow local corrosion phenomenon presence.And the chromium contained by rustless steel is rustless steel tool
There is corrosion proof reason, the rustless steel containing more than 10.5% chromium can form reliable selfreparing chromium oxide layer, have rustless steel
There is corrosion resistance, and improve non-oxidizability, wearability and tensile strength.Therefore ferrite series stainless steel applied range
General.Ferritic stainless steel has excellent resistance to chloride stress corrosion and high temperature oxidation resistance, the advantages of expansion rate is little, and
Ferritic stainless steel processing hardening tendency is little, it is easy to machine-shaping.But ferritic stainless steel toughness under room temperature and cryogenic conditions
Difference, not intergranular corrosion resistance, the shortcomings of welding performance difference.But, ferritic stainless steel easily produces intercrystalline corrosion, and intercrystalline corrosion is broken
Bad intercrystalline combination, substantially reduces the mechanical strength of metal.The rustless steel of intercrystalline corrosion is produced, when effect is stressed,
I.e. can intercrystalline fracture, intensity be almost wholly absent, this is a kind of stainless most dangerous failure mode.Do not have pin at present
Patented technology to ferritic stainless steel intergranular corrosion resistance heat treatment, this will reduce the service life of ferritic stainless steel.
Content of the invention
The technical problem to be solved is：For prior art deficiency, a kind of step is provided simply, processing cost
Low, ferritic stainless steel intergranular corrosion resistance performance can be processed, the intercrystalline corrosion of ferritic stainless steel is eliminated, improve ferrum
Ferritic stainless steel machinery intensity, when ferritic stainless steel is stressed effect, is not in intercrystalline fracture, causes intensity several
Problem is wholly absent, so as to effectively improve the raising ferrite stainless of ferritic stainless steel overall performance and service life comprehensively
The process of steel decay resistance.
Techniques discussed above is solved the problems, such as, the technical scheme that the present invention takes is：
The present invention is a kind of process for improving ferritic stainless steel decay resistance, described raising ferrite stainless
The processing step of the process of steel decay resistance is：1) ferritic stainless steel former material is placed in firing equipment and heats；
2) 840 DEG C -860 DEG C of annealing temperature is heated to；3) annealing temperature 20min-40min is kept；4) ferritic stainless steel former material is taken out
Cooling, forms ferritic stainless steel finished product.
When ferritic stainless steel former material is placed on heating in firing equipment, firing equipment is box-annealing furnace, takes out ferrum
During the cooling of ferritic rustless steel former material, by water cooling is cooled down, and room temperature is cooled to.
When being heated with annealing temperature to ferritic stainless steel former material, the chromium component in ferritic stainless steel former material can
Quickly spread to grain boundaries, and so that the chromium depleted degree of Cr depletion zone is reduced or disappear.
The chemical composition of described ferritic stainless steel includes carbon, silicon, manganese, phosphorus, sulfur, titanium, niobium.
The quality parts ratio of described each chemical composition is respectively：Carbon≤0.030, silicon≤1.00, manganese≤1.00, phosphorus≤
0.040, sulfur≤0.015, titanium：0.10-0.60, niobium：0.10-0.30.
The preferred scope of the annealing temperature of described ferritic stainless steel former material is 830 DEG C -870 DEG C.
The processing step of the process of described raising ferritic stainless steel decay resistance also includes ferrite stainless
Steel Susceptibility To Intergranular Corrosion testing procedure, Susceptibility To Intergranular Corrosion testing procedure is carried out after ferritic stainless steel finished product is formed,
Ferritic stainless steel finished product is placed in test solution and is tested.
When carrying out Susceptibility To Intergranular Corrosion test, described test solution chemical composition includes sulphuric acid, potassium rhodanate, sulphuric acid
Sodium, sulphuric acid, potassium rhodanate, the preparation quality parts ratio of sodium sulfate are：5:0.1:1.
Using technical scheme, following beneficial effect can be obtained：
The process for improving ferritic stainless steel decay resistance of the present invention, logical to ferritic stainless steel former material
Cross above-mentioned steps process, the corrosion among crystalline grains for enabling to ferritic stainless steel change, when ferritic stainless steel without
When crossing above-mentioned processing step heat treatment, the Ra value (surface roughness) of ferritic stainless steel illustrates ferrite not 20% or so
The sensitivity of rust steel intercrystalline corrosion is very high.When ferritic stainless steel is after above-mentioned processing step carries out heat treatment, ferrite is not
The Ra value of rust steel is reduced to 1%, illustrates that the sensitivity of intercrystalline corrosion has obtained obvious improvement.The raising ferrite of the present invention is not
The process of rust steel decay resistance, step is simple, is not required to put into too many equipment and material, and processing cost is low, can be to ferrum
Ferritic rustless steel intergranular corrosion resistance performance is processed, and eliminates the intercrystalline corrosion of ferritic stainless steel, improves ferritic stainless steel
Mechanical strength, when ferritic stainless steel is stressed effect, is not in intercrystalline fracture, causes intensity to be almost wholly absent
Problem, so as to effectively improve ferritic stainless steel performance and used life comprehensively.
Specific embodiment
Below by the description of embodiment, the specific embodiment of the present invention is described in further detail：
The present invention is a kind of process for improving ferritic stainless steel decay resistance, described raising ferrite stainless
The processing step of the process of steel decay resistance is：1) ferritic stainless steel former material is placed in firing equipment and heats；
2) 840 DEG C -860 DEG C of annealing temperature is heated to；3) annealing temperature 20min-40min is kept；4) ferritic stainless steel former material is taken out
Cooling, forms ferritic stainless steel finished product.Ferritic stainless steel former material is processed by above-mentioned steps, enables to ferrite not
The corrosion among crystalline grains of rust steel change, and when ferritic stainless steel is without above-mentioned processing step heat treatment, ferrite is not
The Ra value (surface roughness) of rust steel illustrates that the sensitivity of ferritic stainless steel intercrystalline corrosion is very high 20% or so.When ferrum element
Body rustless steel is after above-mentioned processing step carries out heat treatment, and the Ra value of ferritic stainless steel is reduced to 1%, and intercrystalline corrosion is described
Sensitivity obtained obvious improvement.The process of the raising ferritic stainless steel decay resistance of the present invention, step letter
Single, processing cost is low, and ferritic stainless steel intergranular corrosion resistance performance can be processed, and eliminates the intergranular of ferritic stainless steel
Corrosion, improves ferritic stainless steel mechanical strength, when ferritic stainless steel is stressed effect, is not in disconnected along crystal boundary
Split, cause intensity that problem is almost wholly absent, so as to effectively improve ferritic stainless steel performance and used life comprehensively.
When ferritic stainless steel former material is placed on heating in firing equipment, firing equipment is box-annealing furnace, takes out ferrum
During the cooling of ferritic rustless steel former material, by water cooling is cooled down, and room temperature is cooled to.Said structure, firing equipment is easy to ferrum
Ferritic rustless steel former material carries out convenient and swift processing, and is easy to the accurately annealing temperature of control heating and heating to be continuously applied,
Guarantee that the processing step of the process of the raising ferritic stainless steel decay resistance according to the present invention carries out heat treatment, it is ensured that
Ferritic stainless steel end properties meet the requirements.
Chromium (Cr) composition when being heated with annealing temperature to ferritic stainless steel former material, in ferritic stainless steel former material
Quickly can spread to grain boundaries so that the chromium depleted degree of Cr depletion zone reduces or disappears.So, by persistently heating, can make
Change inside ferritic stainless steel former material, reach thermal effectiveness.
The chemical composition of described ferritic stainless steel includes carbon, silicon, manganese, phosphorus, sulfur, titanium, niobium.
The quality parts ratio of each chemical composition of described ferritic stainless steel is respectively：Carbon (C)≤0.030, silicon (Si)
≤ 1.00, manganese (Mn)≤1.00, phosphorus (P)≤0.040, sulfur (S)≤0.015, titanium (Ti)：0.10-0.60, niobium (Nb)：0.10-
0.30.According to the ferritic stainless steel that above-mentioned chemical composition and mass ratio are manufactured, through process of the present invention
After heat treatment, intensity is improved, overall performance reliability.
The preferred scope of the annealing temperature of described ferritic stainless steel former material is 830 DEG C -870 DEG C.Such temperature model
Enclose, can most effectively guarantee to change inside ferritic stainless steel former material, improve overall performance.
The processing step of the process of described raising ferritic stainless steel decay resistance also includes ferrite stainless
Steel Susceptibility To Intergranular Corrosion testing procedure, Susceptibility To Intergranular Corrosion testing procedure is carried out after ferritic stainless steel finished product is formed,
Ferritic stainless steel finished product is placed in test solution and is tested.
When carrying out Susceptibility To Intergranular Corrosion test, described test solution chemical composition includes sulphuric acid, potassium rhodanate, sulphuric acid
Sodium, sulphuric acid, potassium rhodanate, the preparation quality parts ratio of sodium sulfate are：5:0.1:1.
By carrying out Susceptibility To Intergranular Corrosion test, when the Ra value (surface roughness) of ferritic stainless steel is higher, explanation
Susceptibility To Intergranular Corrosion is more serious, and when the ferritic stainless steel through Overheating Treatment carries out Susceptibility To Intergranular Corrosion test test,
The Ra value (surface roughness) of ferritic stainless steel is substantially reduced, and is illustrated that corrosion among crystalline grains are obviously improved, is had
Effect improves the mechanical strength of ferritic stainless steel.
The process for improving ferritic stainless steel decay resistance of the present invention, logical to ferritic stainless steel former material
Cross above-mentioned steps process, the corrosion among crystalline grains for enabling to ferritic stainless steel change, when ferritic stainless steel without
When crossing above-mentioned processing step heat treatment, the Ra value (surface roughness) of ferritic stainless steel illustrates ferrite not 20% or so
The sensitivity of rust steel intercrystalline corrosion is very high.When ferritic stainless steel is after above-mentioned processing step carries out heat treatment, ferrite is not
The Ra value of rust steel is reduced to 1%, illustrates that the sensitivity of intercrystalline corrosion has obtained obvious improvement.The raising ferrite of the present invention is not
The process of rust steel decay resistance, step is simple, is not required to put into too many equipment and material, and processing cost is low, can be to ferrum
Ferritic rustless steel intergranular corrosion resistance performance is processed, and eliminates the intercrystalline corrosion of ferritic stainless steel, improves ferritic stainless steel
Mechanical strength, when ferritic stainless steel is stressed effect, is not in intercrystalline fracture, causes intensity to be almost wholly absent
Problem, so as to effectively improve ferritic stainless steel performance and used life comprehensively.
Above the present invention is exemplarily described, it is clear that concrete implementation of the present invention is not limited by aforesaid way
System, if the various improvement that method of the present invention design and technical scheme are carried out are employed, or the not improved structure by the present invention
Think and technical scheme is applied to other occasions, all in the scope of the present invention.
Claims (8)
1. a kind of improve ferritic stainless steel decay resistance process, it is characterised in that：Described raising ferrite is not
The processing step of process of rust steel decay resistance is：1) ferritic stainless steel former material is placed in firing equipment and adds
Heat；2) 800 DEG C -900 DEG C of annealing temperature is heated to；3) annealing temperature 20min-40min is kept；4) ferritic stainless steel original is taken out
Material is cooled down, and forms ferritic stainless steel finished product.
2. according to claim 1 improve ferritic stainless steel decay resistance process, it is characterised in that：By ferrum
When ferritic rustless steel former material is placed on heating in firing equipment, firing equipment is box-annealing furnace, takes out ferritic stainless steel original
During material cooling, by water cooling is cooled down, and room temperature is cooled to.
3. according to claim 1 improve ferritic stainless steel decay resistance process, it is characterised in that：To ferrum
When ferritic rustless steel former material is heated with annealing temperature, the chromium component in ferritic stainless steel former material can be quickly to grain boundaries
Diffusion, and so that the chromium depleted degree of Cr depletion zone is reduced or disappear.
4. according to claim 1 improve ferritic stainless steel decay resistance process, it is characterised in that：Described
The chemical composition of ferritic stainless steel include carbon, silicon, manganese, phosphorus, sulfur, titanium, niobium.
5. according to claim 4 improve ferritic stainless steel decay resistance process, it is characterised in that：Described
The quality parts ratio of each chemical composition be respectively：Carbon≤0.030, silicon≤1.00, manganese≤1.00, phosphorus≤0.040, sulfur≤
0.015, titanium：0.10-0.60, niobium：0.10-0.30.
6. according to claim 1 improve ferritic stainless steel decay resistance process, it is characterised in that：Described
Ferritic stainless steel former material annealing temperature preferred scope be 830 DEG C -870 DEG C.
7. according to claim 1 improve ferritic stainless steel decay resistance process, it is characterised in that：Described
The processing step of process of raising ferritic stainless steel decay resistance also include that ferritic stainless steel intercrystalline corrosion is quick
Perceptual testing procedure, Susceptibility To Intergranular Corrosion testing procedure is carried out after ferritic stainless steel finished product is formed, by ferrite stainless
Steel finished product is placed in test solution to be tested.
8. according to claim 7 improve ferritic stainless steel decay resistance process, it is characterised in that：Carry out
During Susceptibility To Intergranular Corrosion test, described test solution chemical composition includes sulphuric acid, potassium rhodanate, sodium sulfate, sulphuric acid, sulfur cyanogen
Changing potassium, the preparation quality parts ratio of sodium sulfate is：5:0.1:1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610893444.1A CN106435103A (en) | 2016-10-13 | 2016-10-13 | Technological method for improving corrosion resistance of ferritic stainless steel |
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| CN201610893444.1A CN106435103A (en) | 2016-10-13 | 2016-10-13 | Technological method for improving corrosion resistance of ferritic stainless steel |
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Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5996253A (en) * | 1982-11-22 | 1984-06-02 | Sumitomo Metal Ind Ltd | Ferritic stainless steel with superior corrosion resistance |
| CN1123562A (en) * | 1994-01-26 | 1996-05-29 | 川崎制铁株式会社 | Method of manufacturing stainless steel sheet of high corrosion resistance |
| JP2002361303A (en) * | 2001-06-07 | 2002-12-17 | Sumitomo Metal Ind Ltd | Stainless steel plate excellent in contamination resistance and corrosion resistance, and manufacturing method therefor |
| CN1807672A (en) * | 2006-02-17 | 2006-07-26 | 太原钢铁(集团)有限公司 | Middle content chromium copper, iron-containing antiseptic anticreas rustless steel sheet belt and its production method |
| CN101151389A (en) * | 2005-08-17 | 2008-03-26 | 杰富意钢铁株式会社 | Ferritic stainless-steel sheet with excellent corrosion resistance and process for producing the same |
| CN101538683A (en) * | 2008-03-19 | 2009-09-23 | 宝山钢铁股份有限公司 | Ferritic stainless steel with excellent formability and manufacturing method thereof |
| CN101573466A (en) * | 2006-12-28 | 2009-11-04 | Posco公司 | Ferritic stainless steel with execellent corrosion resistnace and excellent discoloration resistance |
| CN102741445A (en) * | 2010-02-02 | 2012-10-17 | 杰富意钢铁株式会社 | Highly corrosion-resistant cold-rolled ferrite stainless steel sheet having excellent toughness, and process for production thereof |
| CN103194690A (en) * | 2013-04-15 | 2013-07-10 | 丹阳恒庆复合材料科技有限公司 | Stainless steel with intergranular corrosion resistance and preparation method thereof |
| CN103866194A (en) * | 2014-03-21 | 2014-06-18 | 东北大学 | Abnormally segregated stanniferous low-clearance ferritic stainless steel and preparation method thereof |
-
2016
- 2016-10-13 CN CN201610893444.1A patent/CN106435103A/en active Pending
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5996253A (en) * | 1982-11-22 | 1984-06-02 | Sumitomo Metal Ind Ltd | Ferritic stainless steel with superior corrosion resistance |
| CN1123562A (en) * | 1994-01-26 | 1996-05-29 | 川崎制铁株式会社 | Method of manufacturing stainless steel sheet of high corrosion resistance |
| JP2002361303A (en) * | 2001-06-07 | 2002-12-17 | Sumitomo Metal Ind Ltd | Stainless steel plate excellent in contamination resistance and corrosion resistance, and manufacturing method therefor |
| CN101151389A (en) * | 2005-08-17 | 2008-03-26 | 杰富意钢铁株式会社 | Ferritic stainless-steel sheet with excellent corrosion resistance and process for producing the same |
| CN1807672A (en) * | 2006-02-17 | 2006-07-26 | 太原钢铁(集团)有限公司 | Middle content chromium copper, iron-containing antiseptic anticreas rustless steel sheet belt and its production method |
| CN101573466A (en) * | 2006-12-28 | 2009-11-04 | Posco公司 | Ferritic stainless steel with execellent corrosion resistnace and excellent discoloration resistance |
| CN101538683A (en) * | 2008-03-19 | 2009-09-23 | 宝山钢铁股份有限公司 | Ferritic stainless steel with excellent formability and manufacturing method thereof |
| CN102741445A (en) * | 2010-02-02 | 2012-10-17 | 杰富意钢铁株式会社 | Highly corrosion-resistant cold-rolled ferrite stainless steel sheet having excellent toughness, and process for production thereof |
| CN103194690A (en) * | 2013-04-15 | 2013-07-10 | 丹阳恒庆复合材料科技有限公司 | Stainless steel with intergranular corrosion resistance and preparation method thereof |
| CN103866194A (en) * | 2014-03-21 | 2014-06-18 | 东北大学 | Abnormally segregated stanniferous low-clearance ferritic stainless steel and preparation method thereof |
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