CN101874126A - Low chrome ferritic stainless steel with high corrosion resistance and stretchability and method of manufacturing the same - Google Patents
Low chrome ferritic stainless steel with high corrosion resistance and stretchability and method of manufacturing the same Download PDFInfo
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- CN101874126A CN101874126A CN200880117387A CN200880117387A CN101874126A CN 101874126 A CN101874126 A CN 101874126A CN 200880117387 A CN200880117387 A CN 200880117387A CN 200880117387 A CN200880117387 A CN 200880117387A CN 101874126 A CN101874126 A CN 101874126A
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- 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
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- 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
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- 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
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- 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
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- C22C38/001—Ferrous alloys, e.g. steel alloys containing N
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- C22C38/004—Very low carbon steels, i.e. having a carbon content of less than 0,01%
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- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
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- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/20—Ferrous alloys, e.g. steel alloys containing chromium with copper
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- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
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- 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
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- 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
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Abstract
The present invention relates to a low chrome ferritic stainless steel with a high corrosion resistance and stretchability and a method of manufacturing the same, wherein the low chrome ferritic stainless steel with the high corrosion resistance and stretchability is composed of C of 0.03wt% or less, Si of 0.5wt% or less, Mn of 0.5wt% or less, P of 0.035wt% or less, S of 0.01wt% or less, Cr of 14 to 16wt%, Mo of 0.2wt% or less, N of 0.030wt% or less, Cu of 0.5wt% or less, Al of 0.05 wt% or less, Ni of 0.2wt% or less, C+N of 0.040wt% or less, Ti of 0.5wt% or less, remaining Fe and, inevitably added impurities, being controlled in EL value defined by Equation 1 below to be 33 or more and in P.I. value defined by Equation 2 below to be in a range of 14 to 16. EL= -162.1*(C+N)-0.2*Cr-l.l*Mo-0.2*Ti/(C+N)+42.2 (1) P.I.=Cr+3.3Mo (2).
Description
Technical field
The present invention relates to a kind of have high erosion resistance and ductile low chrome ferritic stainless steel and manufacture method thereof, more particularly, relate to a kind of exhaust system that is used for high various pipes of requirement erosion resistance height and plasticity and automobile the cold-zone sound damper and have high erosion resistance and ductile low chrome ferritic stainless steel and manufacture method thereof.
Background technology
Usually, in ferritic stainless steel, add Cr and Mo to improve erosion resistance.Yet when adding expensive Cr and Mo, manufacturing cost increases, and unit elongation reduces, and makes deteriorated ductility when the sound damper that forms the punching press type etc., thereby makes the stainless steel fracture.In addition, when winter temperature is low, afterwards under the situation of extension tube, often rupture at TIG welding as exhaust system end pipe etc.
In order to address these problems, people have known several conventional arts.In No. 0930375 European patent, disclose a kind of by one-tenth is grouped into hot-rolled condition in conjunction with improving deep drawability (dipdrawability) and the manufacture method that becomes ridge performance (ridging property).In the 2000-328197 Japanese Patent Laid is announced, disclose and a kind ofly improved the method for surface luster and plasticity by adding an amount of Al.In addition, in No. 0765741 European patent, disclose and a kind ofly improved into ridge resistance (ridge resistance) and the anisotropic method in plane by composition, rolling condition and annealing conditions being carried out optimization.In the 1995-032997 Japanese Patent Laid was announced, the one-tenth that has proposed to have the cheap ferritic stainless steel of high erosion resistance in atmospheric environment was grouped into reference and creates conditions; Yet the content of Cr is limited in high 17% to 32% the scope of Cr content than this patent.
Yet above-mentioned patent is unqualified to be used to satisfy erosion resistance and plasticity and to satisfy the composition that requires cheaply of user expectation simultaneously and create conditions.Therefore, under the situation of the expansion of sound damper that ferritic stainless steel is used for high erosion resistance of needs and high plasticity and pipe, can not satisfy the specification of quality of cold-rolled products.
Summary of the invention
Technical problem
The object of the present invention is to provide a kind of have high erosion resistance and ductile low chrome ferritic stainless steel and manufacture method thereof, Heating temperature, finishing temperature and thermal annealing and the cold annealing conditions of control strand, described method can be improved ductile-brittle transition temperature (DBTT) by the add-on of control Ca, Mg and Zr, and can reduce manufacturing cost by the add-on of utilizing the EL formula (formula 1) of calculating unit elongation and the P.I. formula (formula 2) of calculating fitness index (fitting index) to reduce expensive material Cr and Mo.In addition, another object of the present invention is to provide a kind of have high erosion resistance and ductile low chrome ferritic stainless steel and manufacture method thereof, described method can be by using alloying element C, N, Si, Mn, Cr, Mo and Ti that the control of EL formula and P.I. formula optimization ground adds content and the content ratio of Ti%/(C%+N%), thereby improve the pipe scalability of the welding portion of TIG pipe.
Technical scheme
Have high erosion resistance and ductile low chrome ferritic stainless steel by 0.03wt% or C still less according to of the present invention, 0.5wt% or Si still less, 0.5wt% or Mn still less, 0.035wt% or P still less, 0.01wt% or S still less, the Cr of 14wt% to 16wt%, 0.2wt% or Mo still less, 0.030wt% or N still less, 0.5wt% or Cu still less, 0.05wt% or Al still less, 0.2wt% or Ni still less, 0.040wt% or C+N still less, 0.5wt% or Ti still less, surplus is Fe and inevitably adds impurity and form, and be controlled as the EL value that limits by following formula 1 be 33 or P.I. value bigger and that limit by following formula 2 in 14 to 16 scope.
EL＝-162.1×(C+N)-0.2×Cr-1.1×Mo-0.2×Ti/(C+N)+42.2(1)
P.I.＝Cr+3.3Mo (2)
In addition, in the present invention, have high erosion resistance and ductile low chrome ferritic stainless steel and can comprise any one composition at least of from the group of forming by 0.005wt% or Ca still less, 0.005wt% or Mg still less and 0.01wt% or Zr still less, selecting.
In addition, in the present invention, preferably, Ti/ (C+N) is than in 15 to 20 scope.
In addition, the method for manufacturing according to the present invention with high erosion resistance and ductile low chrome ferritic stainless steel comprises: at the strand of the ferritic stainless steel of the above-mentioned composition of finishing temperature hot rolling of 1230 ℃ to 1280 ℃ Heating temperatures and 740 ℃ to 850 ℃; At 900 ℃ to the 1000 ℃ described strands of thermal annealing; Make strand have 50% or bigger cold draft at 900 ℃ to 1000 ℃ cold annealing strands; Regulating described strand makes strand have in ASTM crystal grain size number the particle size of 6.0 to 7.0 scope.
Beneficial effect
As mentioned above, according to the present invention, Heating temperature, finishing temperature and thermal annealing and the cold annealing conditions of control strand, can improve ductile-brittle transition temperature (DBTT) by the add-on of regulating Ca, Mg and Zr, and can reduce manufacturing cost by the add-on of utilizing the EL formula (formula 1) of calculating unit elongation and the P.I. formula (formula 2) of calculating fitness index (fitting index) to reduce expensive material Cr and Mo.In addition, also can regulate the content ratio of the content of alloying element C, the N, Si, Mn, Cr, Mo and the Ti that add and Ti%/(C%+N%), thereby improve the pipe scalability of the welding portion of TIG pipe by using EL formula and P.I. formula optimization ground.Thereby, can make have high erosion resistance at low temperatures, the low chrome ferritic stainless steel cold-rolled steel of the cheapness of unit elongation, ductility and pipe scalability.So, can guarantee that material can be used in the end and the sound damper of automobile exhaust system.
Description of drawings
Fig. 1 be illustrate 15Cr-Ti steel (No. 1 sample) in cold annealing (cold annealing) back the diagrammatic sketch according to the variation of the unit elongation of the variation of ASTM crystal grain size number.
Fig. 2 illustrates the diagrammatic sketch of 15Cr-Ti steel according to the variation of the unit elongation of the ratio of Ti/ (C+N).
Fig. 3 illustrates the diagrammatic sketch of 15Cr-Ti steel according to the variation of the ductile-brittle transition temperature (DBTT) of the variation of the add-on of Ca, Mg and Zr.
Embodiment
Hereinafter, the present invention is described with reference to the accompanying drawings.
The 409L steel is the 11%Cr steel that is used for the sound damper of the various pipes of end of automobile exhaust system and automobile exhaust system.According to the present invention, can solve because of the erosion resistance of 409L steel poor, thereby when it is used for the sound damper of automobile exhaust system, because of the corrosive problem often appears in condensed water.In addition, 430 steel are 17.5%Cr steel, though 430 steel have good erosion resistance, but because of the increase of Cr content causes manufacturing cost rising and plasticity and pipe scalability poor, make that 430 steel can not widespread use,, can address this problem according to the present invention.
For this reason, the EL value that will limit by following formula 1 be controlled at 33 or P.I. value bigger and that will limit by following formula 2 be controlled under the condition of 14 to 16 scope, Cr content and Mo content with reduction have high erosion resistance at low temperature simultaneously, the low chrome ferritic stainless steel of ductility and pipe scalability is by 0.03wt% or C still less, 0.5wt% or Si still less, 0.5wt% or Mn still less, 0.035wt% or P still less, 0.01wt% or S still less, the Cr of 14wt% to 16wt%, 0.2wt% or Mo still less, 0.030wt% or N still less, 0.5wt% or Cu still less, 0.05wt% or Al still less, 0.4wt% or Ni still less, 0.040wt% or C+N still less, 0.05wt% or Ti still less, surplus is Fe and inevitably adds the impurity composition.
EL＝-162.1×(C+N)-0.2×Cr-1.1×Mo-0.2×Ti/(C+N)+42.2(1)
P.I.＝Cr+3.3Mo(2)
In the method for making such ferritic stainless steel, the low chrome ferritic stainless steel that preparation is cheap, described low chrome ferritic stainless steel comprise that mentioned component is formed and any one composition at least of from the group of forming by 0.005wt% or Ca still less, 0.005wt% or Mg still less and 0.01wt% or Zr still less, selecting as other alloy composition and satisfy Ti/ (C+N) and compare in 15 to 20 scope.After with the finishing temperature hot rolling of the strand of such steel 1230 ℃ to 1280 ℃ Heating temperature and 740 ℃ to 850 ℃, with it at 900 ℃ to 1000 ℃ thermal annealings (hot-annealed).Cold annealing (cold-annealed) with obtain 50% or bigger cold draft (cold reduction ratio) afterwards, the particle size of material is adjusted in 6.0 to 7.0 the scope in ASTM crystal grain size number.
Hereinafter, will describe composition range of the present invention and limitation reason thereof in detail.
(C, N) C of forming element and N exist with the form of interstitial atom as carbonitride Ti.When the content of C and N uprises, be not formed on carbonitride Ti (C, N) the solid-state C in and the N unit elongation and the deteriorated ductility that make material.Therefore, the content of C is restricted to 0.03% or littler, and the content of N also is restricted to 0.03% or littler.Simultaneously, when the content of C+N uprises, add high-load Ti and make the steel-making inclusion increase, thereby cause many surface imperfection such as incrustation.In addition, mouth of pipe latch up phenomenon takes place when continuous casting, and because of the increase deterioration of the content of solid-state C and N the unit elongation of material.Therefore, the content of C+N is restricted to 0.04% or littler.
Si is the ferritic phase forming element.When the content of Si increased, the stability of ferritic phase uprised and has improved oxidation-resistance.Yet when adding 0.5% or more Si, steel-making Si inclusion increases the feasible surface imperfection that occurs easily.In addition, though Si improves hardness, yield strength and tensile strength, Si deterioration unit elongation, this is unfavorable for plasticity.Therefore, the content of Si is restricted to 0.5% or littler.
When the content of Mn uprised, MnS formed, thus deterioration the corrosive adaptation of antagonism.Therefore, the content of Mn is restricted to 0.5% or littler.
Ni is a γ phase forming element.When the content of Ni increased, γ increased mutually.Therefore, when at coils of hot rolled (coil) back air cooling coiled material, promote the martensitic phase generation, improved intensity and hardness, made the unit elongation deterioration.Therefore, the add-on of Ni is restricted to 0.2% or still less.
P and S form the inclusion such as MnS etc., deterioration erosion resistance and hot rolling plasticity.Therefore, preferably, their content control ground is low as far as possible: the content of P is restricted to 0.035% or littler, and the content of S is restricted to 0.01% or littler.
When the content step-down of Cr, the erosion resistance deterioration.When the content of Cr became too high, erosion resistance improved, and unit elongation is low, deterioration plasticity.Therefore, the content of Cr is restricted to 14% to 16% scope.
When the content of the Mo of costliness increased, erosion resistance improved significantly, and the manufacturing cost of material raises, and the hardness unit elongation that increased deterioration, thus deterioration plasticity.Therefore, under the situation of considering erosion resistance and plasticity, the content of Mo is restricted to 0.2% or still less.
Al is the element that adds as reductor.When adding a large amount of Al, produce surface imperfection.Therefore, the content of Al is restricted to 0.05% or littler.
Cu is the same with Ni, is γ phase forming element.When adding a large amount of Cu, γ increases mutually.Therefore, when air cooling coiled material behind coils of hot rolled, promote the martensitic phase generation, improved intensity and hardness, made the unit elongation deterioration.Therefore, the add-on of Cu is restricted to 0.5% or littler.
When adding too much Ti, the steel-making inclusion increases, and causes many surface imperfection such as incrustation.In addition, mouth of pipe latch up phenomenon takes place when continuous casting, because of the increase deterioration of solid-state Ti content unit elongation, and the add-on of comparing Ti with the content of C+N becomes very low.As Ti/ (C+N) during than step-down, intergranular corrosion takes place make the erosion resistance deterioration.Therefore, under the situation of considering erosion resistance and plasticity, the add-on of Ti is restricted to 0.5% or littler, and Ti/ (C+N) proportional limit is in 15 to 20 scope.
When Ca, Mg and Zr are added or are added in them two combination separately, crystal grain size in the heat affected zone when TIG welds becomes meticulous, reduced ductile-brittle transition temperature (DBTT), thereby the welding portion that has improved the TIG pipe is such as the pipe scalability under the low temperature in winter.Yet when their add-on was excessive, the growing amount of the oxide inclusion of Ca, Mg and Zr increased, and made the erosion resistance deterioration.So the add-on of Ca is restricted to 0.005% or littler, the add-on of Mg is restricted to 0.005% or littler, and the add-on of Zr is restricted to 0.01% or littler.
When the EL value in the EL calculating formula that obtains in order to improve unit elongation in the present invention becomes less than 33 the time, as the sound damper material of punching press type, its unit elongation and ductility deficiency.Therefore, when being shaped, rupture.So the EL value is restricted to 33 or bigger.
EL＝-162.1×(C+N)-0.2×Cr-1.1×Mo-0.2×Ti/(C+N)+42.2(1)
In addition, the spot corrosion index (P.I.) in formula 2 is when value uprises, improved resistance to corrosion.So,, need to improve expensive element Cr or the content of Mo in order to improve the P.I. value.Yet when their too high levels, unit elongation and deteriorated ductility manufacturing cost simultaneously raise.In addition, cross when low the erosion resistance deterioration when their content.So in order to have erosion resistance and to make between the STS409L steel and 439 steel that manufacturing cost uses in front, the P.I. value in P.I. calculating formula (2) is limited in 14 to 16 the scope.
P.I.＝Cr+3.3Mo(2)
For the ratio of Ti/ (C+N), when the ratio of Ti/ (C+N) became low, the welding portion generation intergranular corrosion after welding.On the contrary, when the ratio of Ti/ (C+N) became too high, the content of solid-state Ti raise to make such as the plasticity deterioration of unit elongation etc.So the proportional limit of Ti/ (C+N) is in 15 to 20 scope.
Next, of the present invention creating conditions and limitation reason will be described.
In hot-rolled condition,, help the recrystallization in the hot-rolled manipulation process along with the Heating temperature of strand uprises.Yet, when Heating temperature was too high, surface imperfection appearred.So the Heating temperature of strand is limited in 1230 ℃ to 1280 ℃ the scope.
Along with the finishing temperature step-down when the hot rolling, accumulation energy changes (variationaccumulation energy) and uprises in course of hot rolling, helps the recrystallization when annealing.Thereby low finishing temperature helps the improvement of unit elongation.Yet, when finishing temperature became low, because of roll and material bonding causes occurring the adhesion surface defective.Therefore, finishing temperature is limited in 740 ℃ to 850 ℃ the scope.
In addition, when the cold draft of material became low, be difficult to remove surface imperfection and guarantee surface properties.On the contrary, when cold draft becomes too high, help improving plasticity.So cold draft is restricted to 50% or bigger when manufactured materials.
Because unit elongation is the best when the ASTM crystal grain size number in annealed steel is in 6.0 to 7.0 scope after the cold annealing, so it is limited in this scope.
Hereinafter, will describe the present invention in detail by embodiment.
(embodiment)
In table 1, represented chemical ingredients, EL calculated value and the P.I. calculated value of sample.In table 2, represented the sample measured unit elongation, voltage rating (nominal potential), exist or do not exist intergranular corrosion generation, make every effort to overcome gloomy value (Erichsen value) at ductile-brittle transition temperature (DBTT) and the dust of the weld part office of TIG pipe.
The ferritic stainless steel of the table 1 by composed as follows of melting in the vacuum melting equipment of 50Kg has been made the ingot casting of thickness 120mm.At the ingot castings of 1250 ℃ of above-mentioned manufacturings of heating, and, has the hot-rolled steel of thickness 3.0mm with manufacturing 800 ℃ finishing temperature hot rolling.Then, with it at 960 ℃ of thermal annealings, pickling subsequently, the thickness of cold rolling one-tenth 1.5mmt and 0.6mmt.Subsequently, with it 960 ℃ of cold annealing, pickling then.Carry out Elongation test and dust and make every effort to overcome gloomy test, use image dissector to measure the crystal grain size of cold annealed steel.
The voltage rating of having tested cold annealed steel by KS D 0238 method, and the voltage rating of cold annealed steel has been carried out five times at V C 10 measured so that it is expressed as mean value.
By being that the cold annealed steel (added the steel of Cr, Zr, Mg and do not added the steel of Cr, Zr, Mg) of 1.5mm is processed into the V-arrangement recess with instrument size and impacts sample with thickness, and in+20 ℃ to-70 ℃ scope, measure the Impact Test temperature with 10 ℃ interval, measure ductile-brittle transition temperature.
Table 1
Table 2
Hereinafter, test result will be described.Chemical ingredients, the calculated value of EL and the calculated value of P.I. of table 1 and table 2 expression sample, erosion resistance (voltage rating) and ductility (dust is made every effort to overcome gloomy value) etc.In steel of the present invention, regulated the content of Cr and Mo, thereby the P.I. value of formula 2 that utilize to calculate the P.I. value and traditional steel (409L:No.13,439 steel: moderate product property No.14) have been represented in 14 to 16 scope.In addition, in steel of the present invention, having regulated content and the Ti/ (C+N) of C, N, Cr, Mo, is 33 or bigger thereby utilize the value of the EL of the formula 1 of calculating the EL value.Thereby, being appreciated that erosion resistance is good in steel of the present invention, the unit elongation of measurement is up to 34% or bigger, and expression ductile dust is made every effort to overcome gloomy value also up to 9.3mm or bigger.In addition, be appreciated that with the ratio of Ti/ (C+N) not the comparative examples in this scope compare, in the steel of the present invention of the ratio of the Ti/ (C+N) in having 15 to 20 the scope of being adjusted in, do not appear at the intergranular corrosion of welding portion.
Fig. 1 illustrates 15Cr-Ti (No. 1 sample) steel at the cold diagrammatic sketch of back according to the variation of the unit elongation of the variation of the ASTM crystal grain size of annealed steel of annealing.Be appreciated that from Fig. 1 when the cold annealing, ASTM crystal grain size number unit elongation in 6.0 to 7.0 scope is best.
Fig. 2 illustrates the ratio of 15Cr-Ti steel according to Ti/ (C+N), the diagrammatic sketch of the variation of the unit elongation after cold annealing, and wherein, because the ratio of Ti/ (C+N) is low, unit elongation is good.Yet, when the ratio of Ti/ (C+N) less than 15 the time, as the result in the table 1, in welding portion generation intergranular corrosion, when the ratio of Ti/ (C+N) surpasses 20, the unit elongation deterioration.So, under the situation of the intergranular corrosion of considering the weld part office and unit elongation, need to add Ti and regulate the ratio of Ti/ (C+N) simultaneously in 15 to 20 scope.
Fig. 3 illustrates the diagrammatic sketch of 15Cr-Ti steel according to the variation of the adding of Ca, Mg and Zr or the ductile-brittle transition temperature that does not add (DBTT), wherein, when adding Ca, or Ca and Mg added together, or add Ca and Zr fashionable together, ductile-brittle transition temperature (DBTT) is low to moderate-50 ℃, thereby under the working temperature situation low as winter, the qualitative change of TIG pipe extendability gets good.
By top specific descriptions and accompanying drawing, optimum embodiment of the present invention is disclosed.Employed term is in order to describe the present invention, rather than to the restriction of implication or to the restriction of the scope of the present invention described in the claims.So, it should be appreciated by those skilled in the art that other embodiment that various modifications can be arranged and be equal to.Thereby scope of the present invention should be limited by the technical conceive of claim.
Claims (4)
1. one kind has high erosion resistance and ductile low chrome ferritic stainless steel, described low chrome ferritic stainless steel comprises 0.03wt% or C still less, 0.5wt% or Si still less, 0.5wt% or Mn still less, 0.035wt% or P still less, 0.01wt% or S still less, the Cr of 14wt% to 16wt%, 0.2wt% or Mo still less, 0.030wt% or N still less, 0.5wt% or Cu still less, 0.05wt% or Al still less, 0.2wt% or Ni still less, 0.040wt% or C+N still less, 0.5wt% or Ti still less, surplus is Fe and inevitably adds impurity, described low chrome ferritic stainless steel be controlled as the EL value that limits by following formula 1 be 33 or P.I. value bigger and that limit by following formula 2 in 14 to 16 scope:
EL＝-162.1×(C+N)-0.2×Cr-1.1×Mo-0.2×Ti/(C+N)+42.2 (1)
P.I.＝Cr+3.3Mo (2)。
2. as claimed in claim 1 have high erosion resistance and a ductile low chrome ferritic stainless steel, comprise from the group of forming by 0.005wt% or Ca still less, 0.005wt% or Mg still less and 0.01wt% or Zr still less, select one or both or two or more.
3. as claimed in claim 1 or 2 have high erosion resistance and a ductile low chrome ferritic stainless steel, and wherein, the ratio of Ti/ (C+N) is in 15 to 20 scope.
4. a manufacturing has the method for high erosion resistance and ductile low chrome ferritic stainless steel, and described method comprises:
At the finishing temperature hot rolling of 1230 ℃ to 1280 ℃ Heating temperatures and 740 ℃ to 850 ℃ strand according to any described ferritic stainless steel in the claim 1 to 3;
At 900 ℃ to the 1000 ℃ described strands of thermal annealing;
Make strand have 50% or bigger cold draft at 900 ℃ to 1000 ℃ cold annealing strands;
Regulating described strand makes strand have in ASTM crystal grain size number the particle size of 6.0 to 7.0 scope.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR10-2007-0119529 | 2007-11-22 | ||
| KR1020070119529A KR20090052954A (en) | 2007-11-22 | 2007-11-22 | Low chrome ferritic stainless steel with high corrosion resistance and stretchability and method of manufacturing the same |
| PCT/KR2008/005744 WO2009066868A1 (en) | 2007-11-22 | 2008-09-30 | Low chrome ferritic stainless steel with high corrosion resistance and stretchability and method of manufacturing the same |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN101874126A true CN101874126A (en) | 2010-10-27 |
Family
ID=40667673
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN200880117387A Pending CN101874126A (en) | 2007-11-22 | 2008-09-30 | Low chrome ferritic stainless steel with high corrosion resistance and stretchability and method of manufacturing the same |
Country Status (4)
| Country | Link |
|---|---|
| EP (1) | EP2220260A4 (en) |
| KR (1) | KR20090052954A (en) |
| CN (1) | CN101874126A (en) |
| WO (1) | WO2009066868A1 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102690997A (en) * | 2011-03-25 | 2012-09-26 | Posco公司 | Ferritic stainless steel and method of manufacturing the same |
| CN107552567A (en) * | 2017-09-08 | 2018-01-09 | 苏州钢特威钢管有限公司 | The preparation method of 1Cr17 ferrite stainless steel pipes |
| CN107873871A (en) * | 2017-11-29 | 2018-04-06 | 苏州市西山宏运材料用品厂 | A kind of anticorrosive tea stir-frying pot |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5152387B2 (en) * | 2010-10-14 | 2013-02-27 | Ｊｆｅスチール株式会社 | Ferritic stainless steel with excellent heat resistance and workability |
| CN102690994B (en) * | 2011-03-25 | 2014-08-13 | 宝山钢铁股份有限公司 | Medium-chromium ferrite stainless steel and manufacturing method thereof |
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| JPS51149116A (en) * | 1975-06-18 | 1976-12-21 | Kawasaki Steel Corp | Process for producing ferritics tainless steelplates without ridging |
| JPS5861258A (en) * | 1981-10-08 | 1983-04-12 | Nisshin Steel Co Ltd | Ferrite stainless steel with superior bulgeability and secondary workability |
| US4690798A (en) * | 1985-02-19 | 1987-09-01 | Kawasaki Steel Corporation | Ultrasoft stainless steel |
| JP2589373B2 (en) * | 1989-05-15 | 1997-03-12 | 株式会社神戸製鋼所 | Ferritic stainless steel with excellent elution resistance in high temperature water |
| CA2123470C (en) * | 1993-05-19 | 2001-07-03 | Yoshihiro Yazawa | Ferritic stainless steel exhibiting excellent atmospheric corrosion resistance and crevice corrosion resistance |
| JPH07150244A (en) * | 1993-11-25 | 1995-06-13 | Sumitomo Metal Ind Ltd | Production of ferritic stainless steel for cold working |
| JP4065579B2 (en) * | 1995-09-26 | 2008-03-26 | Ｊｆｅスチール株式会社 | Ferritic stainless steel sheet with small in-plane anisotropy and excellent ridging resistance and method for producing the same |
| JP3276303B2 (en) * | 1997-04-14 | 2002-04-22 | 川崎製鉄株式会社 | Ferritic stainless steel with excellent rust resistance that does not easily cause initial rust |
| KR100467719B1 (en) * | 2000-12-08 | 2005-01-24 | 주식회사 포스코 | Method of producing ferritic stainless steel sheets having softning, anti-ridging property and excellent spinning formability |
| EP1225242B1 (en) * | 2001-01-18 | 2004-04-07 | JFE Steel Corporation | Ferritic stainless steel sheet with excellent workability and method for making the same |
| WO2003080885A1 (en) * | 2002-03-27 | 2003-10-02 | Nippon Steel Corporation | Cast piece and sheet of ferritic stainless steel, and method for production thereof |
| JP2003342694A (en) * | 2002-05-23 | 2003-12-03 | Jfe Steel Kk | Ferritic stainless steel excellent in spinning workability and used for diameter-enlarged member of gas exhaust system |
| KR100733016B1 (en) * | 2002-06-17 | 2007-06-27 | 제이에프이 스틸 가부시키가이샤 | FERRITIC STAINLESS STEEL PLATE WITH Ti AND METHOD FOR PRODUCTION THEREOF |
| JP3999141B2 (en) * | 2003-02-21 | 2007-10-31 | 日新製鋼株式会社 | Engine exhaust gas path downstream member |
| JP2004323907A (en) * | 2003-04-24 | 2004-11-18 | Nippon Steel Corp | Ferritic stainless steel for automobile exhaust system member having excellent initial rust resistance |
| KR20040110644A (en) * | 2003-06-20 | 2004-12-31 | 주식회사 포스코 | Ferritic stainless steel having an excellent elongation percentage and method thereof |
| JP4451324B2 (en) * | 2004-03-29 | 2010-04-14 | 新日鐵住金ステンレス株式会社 | Ferritic stainless steel for combustion equipment that produces a black scale with excellent adhesion |
-
2007
- 2007-11-22 KR KR1020070119529A patent/KR20090052954A/en not_active Application Discontinuation
-
2008
- 2008-09-30 EP EP08852156A patent/EP2220260A4/en not_active Withdrawn
- 2008-09-30 WO PCT/KR2008/005744 patent/WO2009066868A1/en active Application Filing
- 2008-09-30 CN CN200880117387A patent/CN101874126A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102690997A (en) * | 2011-03-25 | 2012-09-26 | Posco公司 | Ferritic stainless steel and method of manufacturing the same |
| CN107552567A (en) * | 2017-09-08 | 2018-01-09 | 苏州钢特威钢管有限公司 | The preparation method of 1Cr17 ferrite stainless steel pipes |
| CN107873871A (en) * | 2017-11-29 | 2018-04-06 | 苏州市西山宏运材料用品厂 | A kind of anticorrosive tea stir-frying pot |
Also Published As
| Publication number | Publication date |
|---|---|
| WO2009066868A1 (en) | 2009-05-28 |
| EP2220260A4 (en) | 2011-05-04 |
| EP2220260A1 (en) | 2010-08-25 |
| KR20090052954A (en) | 2009-05-27 |
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Open date: 20101027 |