CN107109584A - The excellent economizing type two phase stainless steel of drawing and its manufacture method - Google Patents
The excellent economizing type two phase stainless steel of drawing and its manufacture method Download PDFInfo
- Publication number
- CN107109584A CN107109584A CN201580071218.9A CN201580071218A CN107109584A CN 107109584 A CN107109584 A CN 107109584A CN 201580071218 A CN201580071218 A CN 201580071218A CN 107109584 A CN107109584 A CN 107109584A
- Authority
- CN
- China
- Prior art keywords
- stainless steel
- phase
- steel
- austenite
- phase stainless
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- 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
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/42—Ferrous alloys, e.g. steel alloys containing chromium with nickel with copper
-
- 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
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0247—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
- C21D8/0263—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment following hot rolling
-
- 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
- C21D6/004—Heat treatment of ferrous alloys containing Cr and Ni
-
- 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
- C21D6/005—Heat treatment of ferrous alloys containing Mn
-
- 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
- C21D6/008—Heat treatment of ferrous alloys containing Si
-
- 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
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/005—Modifying the physical properties by deformation combined with, or followed by, heat treatment of ferrous alloys
-
- 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
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0205—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips of ferrous alloys
-
- 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
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
- C21D8/0226—Hot rolling
-
- 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
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
- C21D8/0236—Cold rolling
-
- 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
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0247—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
-
- 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
- C22C38/001—Ferrous alloys, e.g. steel alloys containing N
-
- 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
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
-
- 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
- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
-
- 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
- C22C38/38—Ferrous alloys, e.g. steel alloys containing chromium with more than 1.5% by weight of manganese
-
- 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
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
-
- 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
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/58—Ferrous alloys, e.g. steel alloys containing chromium with nickel with more than 1.5% by weight of manganese
-
- 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
- C21D2211/001—Austenite
-
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Heat Treatment Of Sheet Steel (AREA)
Abstract
The present invention relates to a kind of economizing type two phase stainless steel and its manufacture method that will not occur delayed fracture and be improved drawing.The excellent economizing type two phase stainless steel of drawing of the invention, in terms of weight %, comprising：0.02~0.08% C, 0.5~1.3% Si, 2.5~3.5% Mn, 19~21% Cr, 0.6~1.2% Ni, 0.2~0.3% N, 0.5~1.2% Cu, the Fe of surplus and other inevitable impurity, and the dual phase steel of the ferrite and austenite as annealing, the Md_SIM10 and limiting drawing ratio (LDR) of the temperature determined when reaching 10% corresponding to the amount of the plasticity induced martensite formed after 0.3 logarithmic strain meet following mathematical expressions, 30 DEG C≤Md_SIM10≤0 DEG C (mathematical expression 1) 2.08≤LDR≤2.18 (mathematical expression 2).
Description
Technical field
The present invention relates to the excellent economizing type two phase stainless steel of drawing and its manufacture method.
Background technology
In general, processability and the good austenite stainless steel of corrosion resistance are as base metal using iron (Fe), and
Contain Cr, Ni as main material.In addition, austenite stainless steel is to be by adding the other elements such as Mo and Cu to develop at present
Suitable for the various steels of various uses.
This austenite stainless steel kind is corrosion resistance and the steel grade having superior pitting corrosion resistance, and is low-carbon and is wrapped in terms of weight %
Containing more than 8% Ni compositions.Therefore, Ni price rises caused cost fluctuation amplitude greatly, so as to there is competitiveness decline
The problem of.
Therefore, in order to make up this problem, it is necessary to develop reduction Ni contents while be able to ensure that with austenite not
Corrosion proof new steel grade more than the steel grade that becomes rusty is equal.
Thus, using the two phase stainless steel with the micro organization being made up of the mixture of austenite phase and ferritic phase,
This two phase stainless steel shows the feature of austenite and ferrite.
So far, it is proposed that a variety of two phase stainless steels.
For two phase stainless steel, excellent corrosion resistance, also, and silico-aluminum are provided under a variety of corrosive environments
(ALSI) the austenite stainless steels such as 304,316 are compared, and show more excellent corrosion resistance.
For this two phase stainless steel, not only the manufacturing cost caused by the high valence elements such as Ni, Mo rises, and due to
Ni, Mo etc. are consumed, compared with other steel grades, causes the reduction of price competitiveness.
Therefore, the concern recently to economizing type two-phase (lean duplex) stainless steel in two phase stainless steel becomes in rising
Gesture, wherein, economizing type two-phase (lean duplex) stainless steel is the alloying element for excluding the high prices such as Ni and Mo, and is added
Plus low cost alloying element come replace the high valence elements and raising low-alloy cost advantage two phase stainless steel.
However, the economizing type two phase stainless steel developed recently is mainly widely used in tank, shipping container etc., but
It is that these economizing type two phase stainless steels are such as other conventional two phase stainless steels, compared with austenite, there is mouldability and be limited
The problem of.
Therefore, if point rate and the plasticity induced martensite of the austenite phase in control economizing type two phase stainless steel
The formation behavior of (strain-induced martensite), it is likely that realize the improvement of mouldability, but also presence passes through
The amount of the C+N in austenite phase present in ferritic-austenitic phase is controlled to improve the trend of processability.
This is to make use of the phase-change induced plastic generally occurred in metastable state austenitic steel, in processing and forming, such as
Fruit forms the plasticity induced martensite equivalent to hard phase in deformation position, then the localized necking occurred when processing is pressed down
System, deformation travels to the adjacent parts to form plasticity induced martensite.
Therefore, if the amount of plasticity induced martensite that is formed when being deformed by adjusting adjusts processing setting rate,
The raising of elongation can be realized, but during for drawing, processing induction is formed by cup drawing (cup drawing) processing
Martensite so that as delayed fracture the reason for.
In addition, in clear No. 61-056267 of Japanese Laid-Open Patent, WO02/027056 publications and WO96/18751 publications
Disclose economizing type two phase stainless steel.Wherein, the clear 61-056267 publications of Japanese Laid-Open Patent and WO02/027056 publications
Disclosed in economizing type two phase stainless steel be according to ASTM A240 standardize, the former correspond to S32304 (represent composition as
23Cr-4Ni-0.13N), the latter corresponds to S32101 (it is 21Cr-1.5Ni-5Mn-0.22N to represent composition).
Also, with regard to what is standardized disclosed in KR published patent 2006-0074400 publications and according to ASTM A240
For S81921 steel, in terms of weight %, Ni and Mo content are respectively 2.5%, 2.4%, the alloying element containing high price.
These two phase stainless steels are to design steel compared with mouldability to strengthen based on corrosion resistance, therefore it provides with it is specific
More superior corrosion resistance is compared using the corrosion resistance required for part.In addition, anticorrosion stress-resistant is also more excellent than design requirement item
It is different, so as to provide technical solution, but it is poorer than austenite stainless steel as the mouldability of processing sex-related factors.
Thus, many restrictions are caused needing to be molded, in the application of a variety of industrial circles that bends etc., so as to exist not in economic aspect
Appropriate aspect.Accordingly, it would be desirable to develop exclusion these high valence elements, so as to reduce manufacturing cost, while ensure with 304 steel,
304L steel and 316 steel compare the corrosion resistance of equal level above, especially, mouldability are ensured into the work with 304 steel peer-levels
Industry equipment and a variety of processing and forming two phase stainless steels.
Especially, for the excellent austenite stainless steel of mouldability, the Ni containing more than 4% high price, so that in system
Material cost is very high when making, also, also there are problems that largely consuming as precious resource.
Also, the nitrogen solid solution of the corrosion proof steel for ensuring economizing type two phase stainless steel can be significantly increased in substantial amounts of Mn
Degree, but the field trashes such as the MnS unfavorable to corrosion resistance are easily formed, hinder corrosion proof problem so as to exist.In addition, being come using electricity
During operation, Mn dust etc. can be produced, so as to cause environmental problem.
The item illustrated in above-mentioned background technology is only intended to promote the understanding of the background to the present invention, without being understood that
It is the present invention equivalent to prior art known to general technical staff of the technical field of the invention.
The content of the invention
The technical problem to be solved
The problem of in order to solve this existing, it is an object of the invention to provide the economizing type two-phase stainless that drawing is excellent
Steel and its manufacture method, the economizing type two phase stainless steel prevent the generation of delayed fracture at cup formation (cup forming),
And ensure excellent mouldability and corrosion proof while reducing cost.
Technical scheme
The excellent economizing type two phase stainless steel of drawing of the invention for realizing this purpose, in terms of weight %, bag
Containing 0.02~0.08% C, 0.5~1.3% Si, 2.5~3.5% Mn, 19~21% Cr, 0.6~1.2% Ni,
0.2~0.3% N, 0.5~1.2% Cu, the Fe of surplus and other inevitable impurity, and it is used as the iron element of annealing
The dual phase steel of body and austenite, is surveyed when reaching 10% corresponding to the amount of the plasticity induced martensite formed after 0.3 logarithmic strain
The Md_SIM10 and limiting drawing ratio (LDR) of fixed temperature meet following mathematical expressions：
- 30 DEG C≤Md_SIM10≤0 DEG C --- -- (mathematical expression 1)
2.08≤LDR≤2.18----- (mathematical expression 2).
The excellent economizing type two phase stainless steel of drawing of the invention for realizing this purpose is characterised by, Ovshinsky
Body point rate meets following ranges, and remaining is made up of ferrite：
30≤austenite point rate (γ)≤70.
The excellent economizing type two phase stainless steel of drawing of the invention for realizing this purpose is characterised by,
Process annealing (cold annealing) is carried out to steel under 950~1100 DEG C of scopes, in terms of weight %, the ladle containing 0.02~
0.08% C, 0.5~1.3% Si, 2.5~3.5% Mn, 19~21% Cr, 0.6~1.2% Ni, 0.2~
0.3% N, 0.5~1.2% Cu, the Fe of surplus and other inevitable impurity.
Invention effect
According to the present invention, by adjusting the content of high valence elements Ni, Si, Cu and Mo alloying component, so as to save money
Source, and reduce cost.
Also, with advantages below, i.e. can not only ensure with corrosion resistances more than 304 steel peer-levels, and can also
Enough improve processability.
Brief description of the drawings
Fig. 1 is the figure of the device on determination limit drawing ratio.
Fig. 2 is the chart for the Md_SIM10 for showing steel of the present invention and comparing steel.
Fig. 3 is Md_SIM10 and the graph of a relation of limiting drawing ratio.
Fig. 4 is that the delayed fracture whether figure after cup drawing shown.
Embodiment
Below, referring to the drawings to embodiments of the invention and other in order that skilled addressee readily understands that the present invention
Content needed for item recorded in detail.
But, the present invention is realized in a multitude of different ways in the range of can recording in detail in the claims, therefore, under
The embodiment that face illustrates is only intended to expression, and simply exemplary.
The present invention relates to Ni, Mo, Si, Cu are reduced in the two phase stainless steel with austenite phase and the two-phase of ferritic phase
Deng the excellent economizing type two phase stainless steel of the drawing of the content of high-priced alloying element and its manufacture method.
For economizing type two phase stainless steel, can not only keep with it is same as 304 steel of common austenite stainless steel
Etc. the corrosion resistance of the above, and it also can ensure that elongation more than austenite stainless steel, it can be ensured that same compared with 304 steel
Etc. elongation more than level.
The economizing type two phase stainless steel that the drawing of the present invention is excellent can be used for corrosive environment or shaping mill run, can
Come with being manufactured into such as bar (strip), rod (bar), plate (plate), piece (sheet), pipeline (pipe) or pipe (tube) product
Use.
For economizing type two phase stainless steel, it is ensured that with equal resistance to of 304 steel as austenite stainless steel, 316 steel
Corrosion, while Ni contents are low and both economical, and due to it is easy to ensure that high intensity, therefore, it is possible to as needing corrosion proof sea
It is true while Ni, Mn etc. by reducing in the industrial equipment steel such as water desalting plant, paper pulp, papermaking, chemical device, the present invention
Mouldability and corrosion proof method with austenite peer-level is protected to develop pair that ferritic phase and austenite phase coexist
Phase constitution steel.
Below, the economizing type two phase stainless steel excellent to drawing of the invention is described in detail.
According to the present invention, the various excellents for the two phase stainless steel being made up of austenite and ferrite, while can be true
Protect the flat corrosion resistance of 304 molten steel and drawing.That is, in the present invention, as the chrome stainless steel of low-carbon, containing high nitrogen, and will
Mn content is optimized, while the alloying element such as Ni, Si, Mo, Cu by high price is adjusted to optimal level.Thus, composition is utilized
Composition and annealing temperature suitably adjust austenite and ferritic phase fraction, so as to will be surveyed under conventional stretcher strain speed
Fixed Md_SIM10 temperature, i.e. the amount of the plasticity induced martensite determined after the logarithmic strain for applying 0.3 reaches 10% temperature
Range regulation is -30~0 DEG C, therefore, delayed fracture will not occur in processing and forming, so that being manufactured property and corrosion resistance are excellent
Different austenite and ferritic two phase stainless steel.
For the excellent economizing type two phase stainless steel of drawing of the present invention, be greatly reduced raw material in manufacturing cost into
This, so that price competitiveness is greatly improved, also, delayed fracture resistance is greatly improved after shaping, while ensure corrosion resistance, so that
304 steel for being molded can be replaced.
The excellent economizing type two phase stainless steel of drawing of the present invention, in terms of weight %, comprising 0.02~0.08% C,
0.5~1.3% Si, 2.5~3.5% Mn, 19~21% Cr, 0.6~1.2% Ni, 0.2~0.3% N, 0.5~
1.2% Cu, the Fe of surplus and other inevitable impurity.
Below, the composition restriction reason to the present invention is illustrated.
C, as austenite former, is the effective element for the intensity for increasing material by triggering solution strengthening, in order to
The improvement of intensity is, it is necessary to add more than 0.02% C.However, when adding excessive C, holding in the phase boundary of ferritic-austenitic phase
Easily combined with to the effective such as Cr carbide formers of corrosion resistance, the Cr contents around reduction crystal boundary, so as to reduce corrosion resistant
Corrosion, therefore, in order that corrosion resistance maximization is, it is necessary to add less than 0.08% C.
Si is that a part is added for deoxidation effect, and Si, as ferrite former, is rich in annealing heat-treats
The element combined in ferrite.Therefore, in order to ensure appropriate ferrite phase fraction, it is necessary to add more than 0.5% Si.Work as Si
When being added with the amount less than 0.5%, although the formation phenomenon of the plasticity induced martensite of austenite phase is lived in alloy system
Property, but, so as to occur delayed fracture phenomenon, cause mouldability due to forming excessive plasticity induced martensite in shaping
Reduction.
When Si is added with the amount more than 1.3%, the formation of the mechanical twin in being formed because of plasticity induced martensite causes
The transformation of the deformation mechanism of austenite phase present in dual phase steel, therefore, for needing the formation using plasticity induced martensite
The intent of the present invention of effect and improper.Also, when Si additions are excessive, the flowing of reduction slag (slag) in steel-making
Property, and combined with oxygen and form field trash, so as to reduce corrosion resistance, therefore, Si contents are limited to 0.5~1.3%.
N, as the stabilized element of austenite phase is contributed to together with Ni in two phase stainless steel, is at annealing heat
One kind in the element in austenite phase is enriched in during reason.Therefore, if N content increase, corrosion resistance is consequently increased, energy
Enough obtain high intensity.However, according to the Mn of addition content, N solid solubility can change, in Mn scopes of the invention,
If N content is more than 0.3%, stomata (blow hole), pin hole (pin are produced in casting because of exceeding for nitrogen solid solubility
Hole) etc., so as to trigger surface defect, therefore, it is difficult to stably manufacture steel.Also, in order to ensure the corrosion resistance that 304 molten steel are flat,
The N of addition more than 0.2% is needed, if addition is less than 0.2%, appropriate phase fraction is difficult to ensure that.
Therefore, N content is preferably limited to 0.2~0.3%.
Mn is deoxidier, and is to increase the element of nitrogen solid solubility, and as austenite former, it is used to replace
The Ni of high price.
When Mn content is more than 3.5%, it is difficult to ensure the flat corrosion resistance of 304 molten steel.When this is due to addition substantial amounts of Mn,
Although the solid solubility to nitrogen is effective, is combined with the S in steel and form MnS, so as to reduce corrosion resistance.Also, Mn's contains
When amount is less than 2.5%, appropriate austenite phase point can not be also ensured as Ni, Cu, N of austenite former etc. even if regulation
Rate, also, the N added solid solubility is low, so that the abundant solid solution of nitrogen can not be obtained at ambient pressure.Therefore, Mn content limit
It is made as 2.5%~3.5%.
It with Si mono- is all ferrite stabilizer that Cr, which is, be not only to the ferritic phase of two phase stainless steel ensure play
The element of main function, and it is for ensuring that corrosion proof essential elements.
If increase Cr content, corrosion resistance can increase, but in order to keep phase fraction, it is necessary to increase high price Ni or
The content of other austenite formers.Therefore, STS more than 304 is ensured while phase fraction in order to keep two phase stainless steel
Corrosion resistance, Cr content is limited to 19~21%.
It with Mn, Cu and N mono- is all austenite stabilizer element that Ni, which is, to the austenite phase of two phase stainless steel ensure play
Main function.Try one's best to reduce cost and reduce expensive Ni content, instead, increase other as austenite
The Mn and N of phase formation element, even if so that reduction Ni, also can fully keep the equilibrium of phase fraction.However, adding to suppress cold
Man-hour occur plasticity induced martensite formation, in order to ensure sufficient austenite stability, it is necessary to add more than 0.6%
Ni.If adding substantial amounts of Ni, austenite point rate can increase, so that appropriate austenite phase fraction is difficult to ensure that, especially,
The manufacturing cost increase of product caused by the Ni of high price, it is difficult to ensure the competitiveness compared with 304.Therefore, Ni contains
Amount is preferably limited to 0.6%~1.2%.
It with Mn, Ni and N mono- is all austenite stabilizer element that Cu, which is, to the austenite phase of two phase stainless steel ensure play
Main function.Try one's best to reduce cost and reduce expensive Ni content, instead, increase other as austenite
Cu, Mn and N of phase formation element, even if so that reduction Ni, also can fully keep the equilibrium of phase fraction.But, in order to suppress
The formation of the plasticity induced martensite occurred during cold working, in order to ensure sufficient austenite stability, it is necessary to add 0.6%
Cu above.If adding substantial amounts of Cu, austenite point rate can increase, so as to be difficult to ensure that appropriate austenite point rate, especially
It, the problem of because of Cu solid solubility, is possible to can occur Welding Problems in production.Therefore, Cu content is preferably limited to 0.6%
~1.2%.
In the present invention, the temperature Md of plasticity induced martensite will be formed30(after the logarithmic strain for applying 0.3 during tension test
The temperature of 50% martensite is formed in the material of deformation) be used in it is conventional two phase stainless steel as a result, it was observed that most of
The amount of plasticity induced martensite in steel is less than 30%, it is known that with conventional Md30Definition be difficult to above-mentioned
Md30Temperature is defined.
Therefore, the main cause of the delayed fracture occurred afterwards according to cup drawing (cup drawing) is that plasticity induces horse
The fact that family name's body, the temperature to formation plasticity induced martensite and the limiting drawing ratio based on delayed fracture carry out a variety of investigations,
Then to Md30Temperature is evaluated after being newly defined as follows.
The plasticity formed after the logarithmic strain of application 0.3 under conventional stretcher strain speed is induced geneva by the present inventor
The amount of body reaches that 10% temperature is defined as Md_SIM10.
The temperature that plasticity induced martensite is formed in two phase stainless steel is defined by method as described above, so
The delayed fracture correlation occurred after cup drawing is analyzed afterwards.
The economizing type two phase stainless steel that the drawing of the present invention is excellent is characterized in that Md_SIM10 is -30~0 DEG C.
The hard phase that plasticity induced martensite is formed when being unstable austenite deformation, can trigger processing to harden, so that
Help to increase the elongation of steel.In the situation of the invention equivalent to the two phase stainless steel being made up of austenite and ferrite
Under, it is possible to use the appropriate distribution of alloying element adjusts the stability of austenite phase.
The present inventor makes in stretcher strain the formation plasticity induced martensite before and after localized necking.However, working as plasticity
When induced martensite is excessively drastically formed, it can rise in deformation early strength, cause processability to reduce, when half portion shape after deformation
During into plasticity induced martensite, because material is excessively deformed so that plasticity induced martensite can not provide side to improving processability
Help.
As described in the present invention, by limiting the temperature and control composition design and phase fraction of the martensite for forming 10%,
Improve mouldability so as to trigger sufficiently processing hardening in shaping, and the delay that can fully suppress to occur after shaping is broken
Split.
The excellent economizing type two phase stainless steel of drawing of the present invention, with volume fraction, preferably by 30~70% Austria
Family name's body and 70~30% ferrite composition.
Contribute to processability to form plasticity induced martensite in austenite phase when being deformed with conventional speed, need
Want more than 30% austenite point rate, especially, when austenite point rate is less than 30%, i.e. ferrite phase fraction is more than 70%
When, occur the surface irregularity caused by ferrite after shaping on the surface.Also, when austenite point rate is more than 70%
When, because of the distribution of alloying element, (austenite former is enriched in austenite phase, and ferrite former is enriched in during annealing
Phenomenon in ferrite) so that the change of austenite stability is beyond being expected, so as to form excessive plasticity induction in shaping
Martensite and produce high intensity, so as to easily occur delayed fracture.
Therefore, austenite point rate is preferably less than 70%.
As shown in figure 1, be make use of as the method for evaluating drawing by cavity plate (die) 1, eyelid retractor (holder) 3, drift
(punch) 5 mould constituted.
Material S is cut to circular and is positioned over above eyelid retractor 3, then move cavity plate 1 and with specific pressure (1
Ton) clamp material S between eyelid retractor 5 and cavity plate 1 in the state of, material S is fabricated to cup by movable punching head 5.
At this moment, a diameter of 50mm of drift 5 or so, when being fully shaped to cup according to material S size, original material S
Size and the ratio of drift 5 be referred to as drawing ratio.With the increase of material S size, cavity plate 1 and the sandwiched power meeting of eyelid retractor 3
Increase therewith, therefore, material S is not easy to be deformed into cup.
During by material S to carry out drawing experiment while 1mm unit increase, maximum material S when not being broken
The ratio of diameter of diameter and drift 5 be referred to as limiting drawing ratio (LDR, Limit Drawing Ratio).
Diameter/punching of LDR (Limit Drawing Ratio (limiting drawing ratio))=blank (blank) without fracture
Head diameter (Ф 50mm)
By drawing evaluation method LDR (Limit Draing Ratio (limiting drawing ratio)) evaluation method, to drawing
Index LDR values are evaluated.Also, delayed fracture is to judge by the following method：Latter made cup is evaluated into drawing
Son (not having the cup for occurring crackle during drawing) is placed 24 hours at normal temperatures, then judges whether produced on the cup Jing Guo drawing
Crackle is given birth to.Typically, when occurring crackle in 24 hours after cup formation, it can be considered as and there occurs delayed fracture, by 24
Do not occur the drawing ratio referred to as limiting drawing ratio of crackle after hour.That is, there is no the limit for occurring delayed fracture after cup formation
Drawing ratio is more excellent, and mouldability is then more excellent.
Below, the economizing type two phase stainless steel excellent to drawing of the invention is described in detail.
Prepare the test piece of the economizing type two phase stainless steel of the compositing range of composition according to the present invention, and carry out hot rolling, height
Temperature annealing (hot annealing), it is cold rolling after carry out process annealing (cold annealing) and adjust the phase fraction of material, and
Determine mouldability.The alloy composition (weight %) of experiment steel grade is shown in table 1 below.
Table 1
| Steel grade | Cr | Mn | Ni | Si | C | N |
| Compare steel 1 | 19.20 | 2.2 | 0.7 | 0.5 | 0.060 | 0.23 |
| Compare steel 2 | 19.20 | 3.6 | 0.7 | 0.5 | 0.060 | 0.19 |
| Invention steel 1 | 20.30 | 3.05 | 0.8 | 0.82 | 0.021 | 0.25 |
| Invention steel 2 | 20.19 | 3.15 | 1.103 | 0.66 | 0.028 | 0.28 |
| Invention steel 3 | 19.38 | 2.8 | 1.023 | 0.9 | 0.029 | 0.283 |
| Invention steel 4 | 20.55 | 3.3 | 0.7 | 1.209 | 0.048 | 0.260 |
The part Experiment steel grade of table 1 is by carry out after hot rolling and high annealing cold rolling manufacturing flakiness (1.0t
Below).For so that following temperature carry out process annealing and pass through the material annealed, the cold rolling material of manufacture is determined into the material
Phase fraction (austenite, ferrite), the logarithmic strain of application 0.3, determines Md_SIM10 under a variety of initial deformation temperatures, and
And, carry out placing 24 hours at normal temperatures after cup pull-out test by the method that illustrates in Fig. 1 and be shaped to cup, to described
The cup of shaping determines the presence or absence of crackle, so that it is determined that limiting drawing ratio.
As shown in Fig. 2 in relatively steel 1, it is known that plasticity induced martensite reaches 10% near 5 DEG C, in invention
In steel 1, it is annealed at 1100 DEG C, it is known that plasticity induced martensite reaches 10% near -6 DEG C, in hair
In bright steel 4, it is the progress process annealing at 1100 DEG C, it is known that martensite reaches 10% near -18 DEG C.
Table 2 shows the ferrite for comparing steel and steel of the present invention, austenite point rate, will not occur the maximum pole of delayed fracture
Limit drawing ratio and Md_SIM10.
Table 2
As shown in table 2, it is known that the phase fraction of the excellent economizing type two phase stainless steel of drawing of the present invention can be with
Alloying component, heat treatment temperature change.
For invention steel, it is known that when being heat-treated in the range of 950~1200 DEG C, ferrite phase fraction is 30
~60% scope, austenite phase fraction is 70~40% scopes.
Show ferrite when being heat-treated respectively with 950 DEG C, 1000 DEG C, 1100 DEG C and 1200 DEG C to invention steel 4
With the phase fraction of austenite.In invention 1~invention of steel steel 4, it is known that ferritic phase fraction is about 30~60% scopes,
Austenite phase fraction is 70~40% scope.
As shown in Figure 3 and Figure 4, it is recognised that when Md_SIM10 value is -30~0 DEG C of scope, limit drawing value exceedes
Corresponding to the 2.08 of the limit drawing value of 304 steel, and will not also occur delayed fracture.
And then, it is recognised that when Md_SIM10 value be -30~0 DEG C of scope when, limit drawing value correspond to 2.12~
Between 2.18, the limit drawing value improved compared with 304 steel can be obtained, and will not also occur delayed fracture, moreover,
Compared with when Md_SIM10 values are less than -30, the intensity and elongation of material are more improved.
Specific description has been carried out to the technological thought of the present invention by the preferred embodiment, it should be noted that
It is that above-described embodiment is intended merely to illustrate and propose, is not intended to limitation.As long as also, skill belonging to the present invention
The those of ordinary skill in art field, it would be appreciated that various deformation example can be carried out in the range of the technological thought of the present invention.
Interest field for foregoing invention is determined by claims, the limit for the contents being not exposed in specification
System, the deformation and change belonged in the equivalency range of claims is belonged in the scope of the present invention.
[explanation of symbol]
1：Cavity plate 3：Eyelid retractor
5：Drift S：Material
Claims (3)
1. a kind of excellent economizing type two phase stainless steel of drawing, in terms of weight %, its comprising 0.02~0.08% C, 0.5~
1.3% Si, 2.5~3.5% Mn, 19~21% Cr, 0.6~1.2% Ni, 0.2~0.3% N, 0.5~1.2%
Cu, the Fe of surplus and other inevitable impurity, and as annealing ferrite and austenite dual phase steel, correspond to
The amount of the plasticity induced martensite formed after 0.3 logarithmic strain reaches that the Md_SIM10 and the limit of the temperature determined when 10% are drawn
Prolong and meet following mathematical expressions than (LDR),
- 30 DEG C≤Md_SIM10≤0 DEG C --- -- mathematical expressions 1
2.08≤LDR≤2.18----- mathematical expressions 2.
2. the excellent economizing type two phase stainless steel of drawing according to claim 1, it is characterised in that austenite point rate expires
Sufficient following ranges, remaining is made up of ferrite,
30≤austenite point rate (γ)≤70.
3. the manufacture method of the excellent economizing type two phase stainless steel of a kind of drawing, it is characterised in that in 950~1100 DEG C of scopes
Under to steel carry out process annealing, in terms of weight %, the ladle containing 0.02~0.08% C, 0.5~1.3% Si, 2.5~
3.5% Mn, 19~21% Cr, 0.6~1.2% Ni, 0.2~0.3% N, 0.5~1.2% Cu, the Fe of surplus and
Other inevitable impurity.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1020140190492A KR101641796B1 (en) | 2014-12-26 | 2014-12-26 | Lean duplex stainless steel with excellent drawability and manufacturing method thereof |
| KR10-2014-0190492 | 2014-12-26 | ||
| PCT/KR2015/014089 WO2016105081A1 (en) | 2014-12-26 | 2015-12-22 | Lean duplex stainless steel having superb drawing property and method for producing same |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN107109584A true CN107109584A (en) | 2017-08-29 |
Family
ID=56151022
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201580071218.9A Pending CN107109584A (en) | 2014-12-26 | 2015-12-22 | The excellent economizing type two phase stainless steel of drawing and its manufacture method |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US20170335420A1 (en) |
| KR (1) | KR101641796B1 (en) |
| CN (1) | CN107109584A (en) |
| WO (1) | WO2016105081A1 (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002069592A (en) * | 2000-09-06 | 2002-03-08 | Nippon Steel Corp | Cast stainless steel slab containing two phases of austenite and ferrite and having excellent hot workability |
| CN101558180A (en) * | 2006-10-30 | 2009-10-14 | 山特维克知识产权股份有限公司 | Duplex stainless steel alloy and use of this alloy |
| CN101903554A (en) * | 2008-02-05 | 2010-12-01 | 新日铁住金不锈钢株式会社 | Ferrite-austenite stainless steel sheet excellent in ridging resistance and workability and process for manufacturing the same |
| CN103987867A (en) * | 2011-11-30 | 2014-08-13 | Posco公司 | Lean duplex stainless steel and preparation method thereof |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0683241B1 (en) * | 1994-05-21 | 2000-08-16 | Yong Soo Park | Duplex stainless steel with high corrosion resistance |
| EP1715073B1 (en) * | 2004-01-29 | 2014-10-22 | JFE Steel Corporation | Austenitic-ferritic stainless steel |
| KR101379079B1 (en) * | 2011-11-30 | 2014-03-28 | 주식회사 포스코 | Lean duplex stainless steel |
-
2014
- 2014-12-26 KR KR1020140190492A patent/KR101641796B1/en active IP Right Grant
-
2015
- 2015-12-22 US US15/534,227 patent/US20170335420A1/en not_active Abandoned
- 2015-12-22 WO PCT/KR2015/014089 patent/WO2016105081A1/en active Application Filing
- 2015-12-22 CN CN201580071218.9A patent/CN107109584A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002069592A (en) * | 2000-09-06 | 2002-03-08 | Nippon Steel Corp | Cast stainless steel slab containing two phases of austenite and ferrite and having excellent hot workability |
| CN101558180A (en) * | 2006-10-30 | 2009-10-14 | 山特维克知识产权股份有限公司 | Duplex stainless steel alloy and use of this alloy |
| CN101903554A (en) * | 2008-02-05 | 2010-12-01 | 新日铁住金不锈钢株式会社 | Ferrite-austenite stainless steel sheet excellent in ridging resistance and workability and process for manufacturing the same |
| CN103987867A (en) * | 2011-11-30 | 2014-08-13 | Posco公司 | Lean duplex stainless steel and preparation method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| US20170335420A1 (en) | 2017-11-23 |
| WO2016105081A1 (en) | 2016-06-30 |
| KR101641796B1 (en) | 2016-07-22 |
| KR20160082631A (en) | 2016-07-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US10287645B2 (en) | Method for producing high-strength steel material excellent in sulfide stress cracking resistance | |
| US8293037B2 (en) | Method for producing duplex stainless steel pipe | |
| CN107937828B (en) | F6NM martensitic stainless steel cylinder forging and heat treatment method | |
| CN101956142B (en) | Dual phase steel seamless pipe and processing method thereof | |
| CN103154279A (en) | Method of hot forming a steel blank and the hot formed part | |
| KR101379079B1 (en) | Lean duplex stainless steel | |
| CN101153371B (en) | High-strength cold-formed hot continuous rolled steel plate and method of preparing the same | |
| CN102719743A (en) | Hot-rolled coil plate for oil casing and manufacturing method thereof | |
| AU2014294080A1 (en) | High-strength steel material for oil well and oil well pipes | |
| CN105452512A (en) | Seamless steel pipe for line pipe, and method for producing same | |
| CN104046889B (en) | A kind of guide rail cold rolled continuous annealing band steel and production method thereof | |
| CN104513933A (en) | Inexpensive non-magnetic stainless steel and manufacturing method thereof | |
| CN108884539A (en) | High strength steel and its manufacturing method | |
| CN103987867A (en) | Lean duplex stainless steel and preparation method thereof | |
| CN107532259A (en) | Martensitic stain less steel | |
| CN105980592A (en) | Duplex stainless steel | |
| CN101205589A (en) | Soft ferritic stainless steel and manufacture method thereof | |
| CN104745952A (en) | Pressure vessel steel, manufacturing method thereof and manufacturing method of deep drawing article | |
| RU2728981C1 (en) | Rolled stock for casing and tubing pipes and method of its production | |
| CN102747279A (en) | Oil casing capable of resisting hydrogen sulfide stress corrosion cracking and manufacturing method thereof | |
| CN113166827A (en) | Hot-rolled steel and method for producing same | |
| CN101906586B (en) | Steel for high-strength straight welded pipe and manufacturing method thereof | |
| CN105695882B (en) | J55-grade low-yield-ratio electric resistance welding sleeve steel and manufacturing method thereof | |
| CN112789365B (en) | Austenitic stainless steel with improved strength | |
| JP5887179B2 (en) | Duplex stainless steel with excellent overworkability and method for producing the same |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20170829 |
|
| WD01 | Invention patent application deemed withdrawn after publication |