CN106480355B - Pressure vessel hot rolled steel plate and its manufacturing method - Google Patents
Pressure vessel hot rolled steel plate and its manufacturing method Download PDFInfo
- Publication number
- CN106480355B CN106480355B CN201510885586.9A CN201510885586A CN106480355B CN 106480355 B CN106480355 B CN 106480355B CN 201510885586 A CN201510885586 A CN 201510885586A CN 106480355 B CN106480355 B CN 106480355B
- Authority
- CN
- China
- Prior art keywords
- weight
- steel plate
- hot rolled
- rolled steel
- plank
- 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.)
- Expired - Fee Related
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
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
-
- 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
- C21D8/0247—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
- C22C38/04—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
- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
-
- 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
-
- 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
- C21D2211/009—Pearlite
Abstract
The present invention relates to a kind of pressure vessel hot rolled steel plate and its manufacturing methods.More specifically, the present invention provides a kind of hot rolled steel plate, wherein relative to the total 100 weight % of hot rolled steel plate, C is included：0.1 weight % to 0.2 weight %, Si：Below 0.5 weight % (not including 0 weight %), Mn：0.5 weight % to 1.5 weight %, P：Below 0.03 weight % (not including 0 weight %), S：Below 0.015 weight % (not including 0 weight %), Al：Below 0.05 weight % (not including 0 weight %), N：Below 0.01 weight % (does not include 0 weight %), surplus is Fe and other inevitable impurity, the hot rolled steel plate is made of pearlite and ausferrite microstructure, relative to the gross score 100% of the hot rolled steel plate microscopic structure, the volume fraction of the ferritic structure is 75% to 85%, and the equiaxial crystal ratio of the ausferrite microstructure is 0.7 to 1.3.
Description
Technical field
The present invention relates to a kind of pressure vessel hot rolled steel plate and its manufacturing methods.It is more particularly it relates to a kind of
Intensity and the excellent pressure vessel hot rolled steel plate of ductility and its manufacturing method.
Background technology
For the pressure vessels such as liquified gas container, the fracture pressure after making container in the burst test based on hydraulic pressure
It is extremely important.Therefore, at this moment the intensity of used hot rolled steel plate is significant variable.For this purpose, usually by C, Si, Mn, Ti, Nb,
Mo and V etc. adds in steel impurity content and is reduced in minimum High Purity Steel, to be used in the hot rolled steel plate for making container with high-strength
Degree.
At present, in order to manufacture high tensile hot rolled steel sheet, add in Ti, Nb, V, Mo etc. using the precipitation strength of these elements come
Manufacture hot rolled steel plate or a large amount of addition Cr or Mn etc. are to ensure intensity or by being tempered to the steel for adding in Mn and Cr
Annealing (temper annealing) comes intensifying impact intensity and tensile properties.
However, recently because the security legislations such as container explosion accident are strengthened, under the security legislation after reinforcing, not only
Standard is equipped with to the fracture pressure in burst test, has also appeared the standard to volume of a container expansion rate.Therefore, in order to meet
The security legislation to pressure vessel being reinforced, is not only steel, even hot rolled steel plate also requires excellent ductility.More than
The prior art its focus be only that by the solution strengthening based on alloying components such as C, Si, Mn, Cr, Mo and W or based on Ti,
The precipitation strength of the alloying components such as Nb, Mo reaches high intensity, therefore for the ductility to ensure volume of a container expansion rate
Improvement is conditional.
In addition, in hot rolling technology, an important factor for influencing steel plate material may be exit temperature at finishing (Final
Delivery Temperature, hereinafter referred to as FDT), coiling temperature (Coiling Temperature, hereinafter referred to as CT) with
And in the refrigerating mode that runout table (Run Out Table, ROT) is cooperation coiling temperature (CT).
Particularly, during by runout table (ROT), hot rolled steel plate is by forcing the phase transformation caused by cooling
Journey may have most last phase (phase).This phase transition process can be influenced by temperature and time, therefore even if with phase
Same exit temperature at finishing (FDT) and coiling temperature (CT) can also have different phases due to refrigerating mode, and then influence material.
Conventional hot rolling carries out continuous coo1ing up to coiling temperature after finish to gauge, thus can not form isometric ferrite, there is extension
The problem of property is poor.
Invention content
Technical problem
The present invention provides a kind of pressure vessel hot rolled steel plate and its manufacturing method.
Technical solution
Hot rolled steel plate according to the present invention wherein relative to the total 100 weight % of hot rolled steel plate, may include C：0.1 weight %
To 0.2 weight %, Si：Below 0.5 weight % (not including 0 weight %), Mn：0.5 weight % to 1.5 weight %, P：0.03 weight
Measure below % (not including 0 weight %), S：Below 0.015 weight % (not including 0 weight %), Al：Below 0.05 weight % is (no
Include 0 weight %), N：Below 0.01 weight % (does not include 0 weight %), and surplus is Fe and other inevitable impurity.
Other inevitable impurity may include Cr：Below 0.3 weight % (not including 0 weight %), Ni：0.3 weight
Measure below % (not including 0 weight %), Mo：Below 0.2 weight % (not including 0 weight %), Cu：Below 0.1 weight % (is not wrapped
Containing 0 weight %).
Furthermore the hot rolled steel plate can be made of pearlite and ausferrite microstructure, shown relative to the hot rolled steel plate
The gross score 100% of micro-assembly robot, the volume fraction of the ferritic structure can be 75% to 85%, the body of the pearlitic structrure
Fraction can be 15% to 25%.
The equiaxial crystal ratio (aspect ratio) of the ausferrite microstructure can be 0.7 to 1.3.
Can be 295MPa to 520MPa according to the yield strength of the hot rolled steel plate of the feature, yield strength × elongation
Value can be more than 11,500 and 17,500.
The present invention additionally provides a kind of hot rolled steel plate manufacturing methods, it may include following steps：Prepare steel billet, relative to total
100 weight %, the steel billet include C：0.1 weight % to 0.2 weight %, S i：Below 0.5 weight % (does not include 0 weight
Measure %), Mn：0.5 weight % to 1.5 weight %, P：Below 0.03 weight % (not including 0 weight %), S：0.015 weight % with
Under (do not include 0 weight %), Al：Below 0.05 weight % (not including 0 weight %), N：Below 0.01 weight % (does not include 0 weight
Measure %), surplus is Fe and other inevitable impurity；The steel billet is reheated at 1100 DEG C to 1300 DEG C；It is right
The steel billet of the reheating carries out roughing；Finish to gauge is carried out to the steel billet of the roughing；The plank of the finish to gauge is cooled down；With
And it batches the plank of the cooling and obtains hot rolled steel plate.
Only, the step of being cooled down to the plank of the finish to gauge, it may include following steps：To the plank of the finish to gauge with
The speed of 40 DEG C/s to 60 DEG C/s carries out first time cooling；And to the first time cooling plank with 1 DEG C/s to 8 DEG C/s's
Speed carries out second and cools down.
In addition, other inevitable impurity may include Cr：Below 0.3 weight % (not including 0 weight %), Ni：
Below 0.3 weight % (not including 0 weight %), Mo：Below 0.2 weight % (not including 0 weight %), Cu：Below 0.1 weight %
(not including 0 weight %).
First, reheated at 1100 DEG C to 1300 DEG C to the steel billet the step of, the steel billet can by again plus
Heat 100 minutes to 400 minutes.Later, it is possible to implement the step of roughing is carried out to the steel billet of the reheating.
More specifically, carry out finish to gauge to the steel billet of the roughing the step of, the finish to gauge can be in A1- 20 DEG C to A1+20℃
Within the temperature range of implement, the A1As shown in formula (1).
A1- 15.5 [Cr] -15.2 of=932.1-392.8 [C] -61.9 [Mn]+43.9 [Si]+420.6 [P]+220.0 [Al]
[Ni]+31.5 [Mo] -20 [Cu] --- --- --- --- --- --- ----formulas (1)
In formula (1), [C], [Mn], [Si], [P], [Al], [Cr], [Ni], [Mo] and [Cu] represents respective ingredient
The weight % of content.
The step of carrying out finish to gauge by the steel billet to the roughing, it is 10 μm to 40 that the steel billet of the finish to gauge, which can have size,
μm austenitic microstructure.
The step of being cooled down to the plank of the finish to gauge, it may include following steps：To the plank of the finish to gauge with 40 DEG C/
The speed of s to 60 DEG C/s carries out first time cooling；And to the first time cooling plank with the speed of 1 DEG C/s to 8 DEG C/s
Second is carried out to cool down.
More specifically, with the speed of 40 DEG C/s to 60 DEG C/s cool down for the first time to the plank of the finish to gauge the step of
In, the plank of the finish to gauge can be cooled to A2- 20 DEG C to A2+ 20 DEG C of temperature range, the A2As shown in formula (2).
A2=740.1-35.4 [C] -64.5 [Mn]+29.1 [Si]+16.9 [Cr] -16.9 [Ni] --- --- --- -- formulas (2)
In formula (2), [C], [Mn], [Si], [Cr] and [Ni] represents the weight % of respective component content.
In the step of plank cooled down to the first time with the speed of 1 DEG C/s to 8 DEG C/s cool down for second, institute
Stating the plank of cooling for the first time can be cooled 1 second to 8 seconds.The step of being cooled down by the plank to the finish to gauge, can
The plank of isometric ferrite (polygonal ferrite) structure is formed to obtain.
The step of being cooled down by the plank to the finish to gauge can be obtained relative to microscopic structure gross score 100%
Plank with 75% to 85% isometric ferritic structure and 15% to 25% austenite structure.
The step of obtaining hot rolled steel plate, the plank can be cooled to A by batching the plank of the cooling3-20℃
To A3It is batched after+20 DEG C of temperature range, the A3As shown in formula (3).
A3- 85.7 [Mo]-formulas (3) of=693.4-444.5 [C] -80.5 [Mn] -35.0 [Si] -76.0 [Cr] -35.0 [Ni]
In formula (3), [C], [Mn], [Si], [Cr], [Ni] and [Mo] represents the weight % of respective component content.
In the step of obtaining hot rolled steel plate batching the plank of the cooling, the plank can be with 40 DEG C/s to 60 DEG C/s
Speed be cooled.
It the step of obtaining hot rolled steel plate, can obtain being formed the heat of pearlitic texture by batching the plank of the cooling
Rolled steel plate.
The hot rolled steel plate manufacturing method of the present invention, can also include the following steps：It batches the plank of the cooling and obtains
Hot rolled steel plate；Later, pickling is carried out to obtained hot rolled steel plate.
The hot rolled steel plate can be made of pearlite and ausferrite microstructure, relative to the hot rolled steel plate microscopic structure
Gross score 100%, the volume fraction of the ferritic structure can be 75% to 85%, and the volume fraction of pearlitic structrure can be
15% to 25%.
The yield strength of the hot rolled steel plate can be 295MPa to 520MPa, yield strength × elongation of the hot rolled steel plate
The value of rate can be more than 11,500 and less than 17,500.
Advantageous effect
A kind of hot rolled steel plate can be provided according to the present invention, there is the intensity of more than 295MPa, while there is excellent prolong
Malleability.
Description of the drawings
Fig. 1 shows value derived from use yield strength, elongation and the yield strength × elongation of example and comparative example.
Fig. 2 shows the refrigerating modes of the hot rolled steel plate according to example.
Specific embodiment
With reference to attached drawing and following embodiments, it is possible to advantages of the present invention, feature be expressly understood and realize these side
Method.However, the present invention can be implemented in a variety of ways, it is not limited to embodiment disclosed below.Following realities are provided
The purpose for applying example is, the fully open present invention so that those skilled in the art have to invention content it is whole and sufficient
Solution, protection scope of the present invention should be subject to claims.Reference numeral identical in specification represents identical structure in the whole text
Into element.
Therefore, in the well known technology of some embodiments, will no longer be described in detail, to avoid the present invention
Explained smudgy.It is unless otherwise defined, (academic including technical term and section using all terms in this specification
Language) meaning be exactly the normally understood meaning of those skilled in the art.In specification in the whole text, certain a part " including (or
Comprising) " a certain component when, unless there are especially opposite record, otherwise represent that other components can also be included and it is non-excluded other
Component.Unless otherwise stated, singulative is also intended to including plural form.
The hot rolled steel plate of an illustrative embodiments according to the present invention, wherein relative to 100 weight % of hot rolled steel plate,
It may include C：0.1 weight % to 0.2 weight %, Si：Below 0.5 weight % (not including 0 weight %), Mn：0.5 weight % is extremely
1.5 weight %, P：Below 0.03 weight % (not including 0 weight %), S：Below 0.015 weight % (not including 0 weight %),
Al：Below 0.05 weight % (not including 0 weight %), N：Below 0.01 weight % (do not include 0 weight %), surplus for Fe and its
Its inevitable impurity.
In the following, the reasons why illustrating the composition range of the limitation present invention.
Carbon (C) plays the role of most economical effective in the reinforcing of steel.If the content of the C is less than 0.1 weight %, just not
Enough pearlite can be generated, it is difficult to ensure required intensity.If on the contrary, the content of the C exceed 0.2 weight %, will be because strong
It spends point raising and leads to ductility reduction.Therefore, the content of C can be 0.1 weight % to 0.2 weight %.
Silicon (Si) makes molten steel deoxidization, and with solid solution strengthening effect.If the content of the Si exceeds 0.5 weight %, will
In hot rolling, surface of steel plate forms red scale caused by Si, and not only resulting in plate surface quality becomes very poor, can also drop
Low weldability.Therefore, although silicon must include, content can be below 0.5 weight %.
Manganese (Mn) is the effective element of solution strengthening to steel as Si.In an exemplary embodiment of the present invention
In, it may include more than 0.5 weight %, to show the effect.It only, will if the content of the Mn exceeds 1.5 weight %
Generate very flourishing segregation portion in mid-depth portion when continuous casting working procedure casts steel billet, thus the weldability of final products and into
Type may reduce.Therefore, the content of the Mn can be 0.5 weight % to 1.5 weight %.
Phosphorus (P) is impurity element, and when content exceeds 0.03 weight %, weldability reduces and steel is made to generate brittle wind
Danger can become larger.Therefore, although must include, content can be below 0.03 weight %.
Sulphur (S) is inevitable impurity as the phosphorus (P) element, may with Mn etc. with reference to and formed nonmetallic
Field trash.Therefore, the toughness of steel may substantially reduce, so needing the content of inhibition sulphur as possible.In theory, the content of sulphur
0 weight % is limited to be advantageous, but sulphur will necessarily be contained in manufacturing process.Therefore, although sulphur is the element that will necessarily contain,
But an illustrative embodiments according to the present invention, its content of sulphur (S) element can be below 0.015 weight %.
Aluminium (Al) is for deoxidation and the element that adds, can exceed 0.05 as deoxidier additive amount in process for making
Weight %.Only, if additive amount is excessive, will occur nozzle (nozzle) blocking etc. in continuous casting, thus productivity may
It reduces.Therefore, although must include, content can be below 0.05 weight %.
Nitrogen (N) is to the effective element of the hardness of steel, but there is the shortcomings that not easy to control.Therefore, if the content of nitrogen surpasses
Go out 0.01 weight %, will increase and generate brittle risk.Therefore, although must include, content can be 0.01 weight
Measure below %.
More specifically, it may include as other inevitable impurity：Cr：Below 0.3 weight % (does not include 0 weight
Measure %), Ni：Below 0.3 weight % (not including 0 weight %), Mo：Below 0.2 weight % (not including 0 weight %), Cu：0.1
Below weight % (does not include 0 weight %).Only, other impurity are not limited thereto, and can also be included in addition to this
Customary impurities.
More specifically, the effect of chromium (Cr) is to make steel solution strengthening, postpone bainitic transformation while cooling, to be easily obtained
The ferrite of equiax crystal.Only, if the content of the chromium exceeds 0.3 weight %, ferritic transformation will excessively be postponed, it is impossible to really
Ferrite fraction needed for protecting, thus elongation may be reduced.Moreover, chromium be in process for making step inevitably
The element of addition, therefore chromium content will not be 0 weight %.
Nickel (Ni) has the function of while improves the intensity and toughness of base material.Only, since nickel is expensive element,
Therefore when content exceeds 0.3 weight %, economy can be not only reduced, can also weldability be caused to be deteriorated.Moreover, nickel element is to refine
The element that steel processing step inevitably adds in, therefore nickel content will not be 0 weight %.
Molybdenum (Mo) plays the role of improving yield strength by solution strengthening and improves impact flexibility by intercrystalline strengthening.
Only, since molybdenum is expensive element, when content exceeds 0.2%, cost increase is not only manufactured, can also weldability be caused to become
Difference.Moreover, molybdenum element is the element inevitably added in process for making step, therefore molybdenum content will not be 0 weight %.
Copper (Cu) plays the role of that small precipitate is promoted to be precipitated to improve intensity.Only, if copper content exceeds 0.1 weight
% is measured, hot-workability is will result in and room temperature processability is deteriorated.Moreover, copper is inevitably added in process for making step
The element entered, therefore copper content will not be 0 weight %.
In addition, meeting the hot rolled steel plate of the ingredient and compositional range can be made of pearlite and ausferrite microstructure,
And relative to the gross score 100% of the hot rolled steel plate microscopic structure, the volume fraction of the ferritic structure can be 75%
To 85%.Furthermore relative to the gross score 100% of the hot rolled steel plate microscopic structure, the volume fraction of the pearlitic structrure
Can be 15% to 25%.
As previously mentioned, when the score of ausferrite microstructure is 75% to 85%, hot rolled steel plate can have 295MPa extremely
The yield strength of 520MPa.Moreover, the value of yield strength × elongation of the hot rolled steel plate can be 11, more than 500.
Only, if the score of ausferrite microstructure is less than 75%, the second phase comprising pearlite will exceed 25%,
It is likely to result in elongation variation.If conversely, the score of ausferrite microstructure exceed 85%, the second phase comprising pearlite
15% is will be lower than, is likely to result in intensity variation.Therefore, the value of yield strength × elongation is less than 11,500, and possibly can not
Meet the range of an exemplary embodiment of the present invention.Furthermore the value of the yield strength × elongation the high more can obtain
To good steel, but highest can be 17,500 hereinafter, only not limited to this.
The yield strength is as the intensity a reference value in the tensile test of material, answering when representing to start plastic deformation
Power.If more specifically, there is yield point elongation, the yield strength can be measured on the basis of upper yield point, if not surrendering
Point extension then can measure the yield strength by 0.2% residual deformation (off-set) method.What is be previously mentioned in this specification bends
Definition and the assay method for taking intensity are same as below.More specifically, the elongation represents the ratio of material extension.More specifically
Ground, for the measure of elongation, if tensile test piece is broken, it is possible to measure elongation during fracture.Moreover, if tensile test piece does not have
There is fracture, it is possible to measure and decline the elongation under the intensity of (drop) 80% in the intensity applied.
Tensile test to measure the yield strength and elongation is the Z600 load cells using ZWICK companies
What (Load cell) and BTC-EXMULTI.003 types carried out, and deformation rate speed is 5mm/min.
In addition, the equiaxial crystal ratio (aspect ratio) of the ausferrite microstructure can be 0.7 to 1.3.Equiaxial crystal ratio
(aspect ratio) refers to horizontal and vertical ratio i.e. aspect ratio, by the electron backscatter diffraction (EBSD) for analyzing steel
Analysis is it is known that the equiaxial crystal ratio of the microscopic structure.
More specifically, carrying out 10 EBSD detections in random site with 500 times of multiplying power, TSL is utilized to the data obtained
The basic software Grain Shape Aspect Ratio softwares of 6.0 softwares of OIM Analysis are averaged.
When the aspect ratio of the ausferrite microstructure is 0.7 to 1.3, material anisotropy reduces, thus elongation
It may increase.In particular, it might have the drawing of the drawing procedure conducive to one of liquified gas container production process.On the contrary,
When the ausferrite microstructure aspect ratio less than 0.7 or beyond 1.3 when, drawing be deteriorated, there are produced during container formation
The risk of raw crackle, even if not cracked during drawing, there is also the risks of the crack resistance variation of final products.
The hot rolled steel plate manufacturing method of another illustrative embodiments according to the present invention, includes the following steps：Prepare
Steel billet, relative to 100 total weight %, the steel billet includes C：0.1 weight % to 0.2 weight %, Si：Below 0.5 weight %
(not including 0 weight %), Mn：0.5 weight % to 1.5 weight %, P：Below 0.03 weight % (not including 0 weight %), S：
Below 0.015 weight % (not including 0 weight %), Al：Below 0.05 weight % (not including 0 weight %), N：0.01 weight %
(0 weight % is not included) below, surplus is Fe and other inevitable impurity；To the steel billet at 1100 DEG C to 1300 DEG C
It is reheated；Roughing is carried out to the steel billet of the reheating；Finish to gauge is carried out to the steel billet of the roughing；To the plate of the finish to gauge
Material is cooled down；And it batches the plank of the cooling and obtains hot rolled steel plate.
Wherein, the step of being cooled down to the plank of the finish to gauge, it may include following steps：To the plank of the finish to gauge with
The speed of 40 DEG C/s to 60 DEG C/s carries out first time cooling；And to the first time cooling plank with 1 DEG C/s to 8 DEG C/s's
Speed carries out second and cools down.
It is possible, firstly, to prepare steel billet, relative to 100 total weight %, the steel billet includes C：0.1 weight % to 0.2 weight
Measure %, Si：Below 0.5 weight % (not including 0 weight %), Mn：0.5 weight % to 1.5 weight %, P：Below 0.03 weight %
(not including 0 weight %), S：Below 0.015 weight % (not including 0 weight %), Al：Below 0.05 weight % (does not include 0 weight
Measure %), N：Below 0.01 weight % (does not include 0 weight %), and surplus is Fe and other inevitable impurity.
More specifically, other inevitable impurity may include Cr：Below 0.3 weight % (not including 0 weight %),
Ni：Below 0.3 weight % (not including 0 weight %), Mo：Below 0.2 weight % (not including 0 weight %), Cu：0.1 weight %
(do not include 0 weight %) below, but it is not limited to this.
The ingredient and compositional range of the steel billet are identical with the ingredient and compositional range of aforementioned hot rolled steel plate, therefore omit
The reasons why limiting the ingredient.
It is then possible to the step of implementing to reheat the steel billet at 1100 DEG C to 1300 DEG C.More specifically, institute
Stating steel billet can be reheated 100 minutes to 400 minutes.
If as described above, reheated at 1100 DEG C or more of temperature, it is possible to the temperature of steel billet is ensured, so as to drop
Low rolling load.Only, if reheated at too high a temperature, since the misgrowth of austenite grain can occur
Local Coarsening, it is possible to final microscopic structure be caused to be roughened.Therefore, crystal grain may be uneven.
It is then possible to the step of implementing to carry out roughing to the steel billet of the reheating.
More specifically, the roughing is the intermediate process before finish to gauge, the roughing meaning mentioned in the present specification is all identical.
Thus, it is possible to the steel billet to reheating carries out roughing, so that the steel billet thickness of roughing becomes the reheating steel billet
The 10% to 25% of thickness.Only, roughing final temperature can be very high temperature, so as to ensure follow-up finish to gauge temperature
Degree.This is that those skilled in the art in the invention are readily comprehensible, therefore description is omitted.
It is then possible to the step of implementing to carry out finish to gauge to the steel billet of the roughing.
In the step of carrying out finish to gauge to the steel billet of the roughing, the finish to gauge can be in A1- 20 DEG C to A1+ 20 DEG C of temperature
Implement in the range of degree.The A1Such as with following formula (1) Suo Shi, by A in this specification1- 20 DEG C to A1+ 20 DEG C of temperature range definition
For finishing temperature.
A1- 15.5 [Cr] -15.2 of=932.1-392.8 [C] -61.9 [Mn]+43.9 [Si]+420.6 [P]+220.0 [Al]
[Ni]+31.5 [Mo] -20 [Cu] --- --- --- --- --- --- ----formulas (1)
In formula (1), [C], [Mn], [Si], [P], [Al], [Cr], [Ni], [Mo] and [Cu] represents respective ingredient
The weight % of content.
More than content shows in order to obtain while has the hot rolled steel plate of excellent intensity and ductility, needs to utilize institute
Formula (1) is stated to control the finishing temperature changed based on alloying component.If more specifically, the finishing temperature is more than A1+ 20 DEG C, just
Can make the AUSTENITE GRAIN COARSENING of steel billet, yield strength may reduce, it is thus possible to can not obtain desired yield strength ×
The value of elongation.If moreover, the finishing temperature is less than A1- 20 DEG C, then due to generating mixed crystal group caused by two-phase section rolls
It knits, ductility may reduce, and rolling load greatly increases during hot rolling, and productivity may reduce.The mixed grain structure
Refer to the different crystal grain of granularity and the tissue deposited.
Therefore, when the temperature range carries out hot rolling finish to gauge, the steel billet of the finish to gauge can be obtained with target sizes
That is 10 μm to 40 μm of fine austenite structure.
It is then possible to the step of implementing to cool down the plank of the finish to gauge.The plank of the finish to gauge is cooled down
The step of, it may include following steps：First time cooling is carried out with the speed of 40 DEG C/s to 60 DEG C/s to the plank of the finish to gauge；With
And second is carried out with the speed of 1 DEG C/s to 8 DEG C/s to the plank of first time cooling and is cooled down.
More specifically, with the speed of 40 DEG C/s to 60 DEG C/s cool down for the first time to the plank of the finish to gauge the step of
In, A can be cooled to2- 20 DEG C to A2+ 20 DEG C of temperature range.Wherein, the A2As shown in formula (2), by A in this specification2-
20 DEG C to A2+ 20 DEG C of temperature range is defined as intermediate steps temperature.
A2=740.1-35.4 [C] -64.5 [Mn]+29.1 [Si]+16.9 [Cr] -16.9 [Ni] --- --- --- -- formulas (2)
In formula (2), [C], [Mn], [Si], [Cr] and [Ni] represents the weight % of respective component content.
More specifically, by the way that the plank of the finish to gauge is cooled to A2- 20 DEG C to A2The first time of+20 DEG C of temperature range
Cooling step, the plank of the finish to gauge can be cooled to the A with the speed of 40 DEG C/s to 60 DEG C/s2- 20 DEG C to A2+ 20 DEG C
Temperature range.
Then, second of step cooled down is carried out with the speed of 1 DEG C/s to 8 DEG C/s by the plank cooled down to the first time
Suddenly, the plank of the first time cooling can be cooled 1 second to 8 seconds.
More than content shows in order to obtain while has the hot rolled steel plate of excellent intensity and ductility, needs to utilize institute
Formula (2) is stated to control the intermediate steps temperature changed based on alloying component.
By conventional continuous coo1ing method come when manufacturing hot rolled steel plate, since the time that coiling temperature is reached from finishing temperature is non-
It is often short, so can not expect generation adequately isometric ausferrite microstructure.Therefore, it will form acicular ferrite, cause to prolong
Malleability is deteriorated.
Intermediate steps temperature is controlled by the alloying component and formula (2) of an illustrative embodiments according to the present invention
Range and cooling condition are spent, isometric ferritic formation can be promoted, so as to improve ductility.The isometric ferrite refers to iron
The aspect ratio of ferritic microscopic structure is 0.7 to 1.3 ferritic structure, because of the formation of the tissue, isometric ferrite fraction
During increase, ductility can be improved.
Only, it is more than A due to the intermediate steps temperature is excessively high2At+20 DEG C, although isometric ferrite can be formed,
Since ferrite crystal grain is grown, yield strength may reduce.On the contrary, intermediate steps temperature is less than A2At -20 DEG C, due to needle
The formation of columnar ferrite, ductility may reduce.Therefore, the value of yield strength × elongation is less than 11,500, it is possible to nothing
Method meets the range of an exemplary embodiment of the present invention.
Therefore, intermediate steps temperature is controlled in the A2- 20 DEG C to A2It, can when being cooled down within the temperature range of+20 DEG C
The plank of isometric ferrite structure is formed to obtain.Moreover, the microscopic structure gross score of the plank relative to the cooling
100%, can have 75% to 85% isometric ferritic structure and 15% to 25% austenite structure.
Finally, it is possible to implement the step of batching the plank of the cooling and obtaining hot rolled steel plate.More specifically, by batching
The plank of the cooling and the step of obtain hot rolled steel plate, the plank can be cooled to A3- 20 DEG C to A3+ 20 DEG C of temperature model
It is batched after enclosing.The A3As shown in formula (3), by the A in this specification3- 20 DEG C to A3+ 20 DEG C of temperature range is defined as rolling up
Take temperature.
A3- 85.7 [Mo]-formulas (3) of=693.4-444.5 [C] -80.5 [Mn] -35.0 [Si] -76.0 [Cr] -35.0 [Ni]
In formula (3), [C], [Mn], [Si], [Cr], [Ni] and [Mo] represents the weight % of respective component content.
In the step of obtaining hot rolled steel plate batching the plank of the cooling, the plank can be with 40 DEG C/s to 60 DEG C/s
Speed be cooled to A3- 20 DEG C to A3It is batched after+20 DEG C of temperature range.
Furthermore described batch can implement 1 minute to 50000 minutes.More specifically, described batch can implement 1 minute to several
Hundred hours.Further, described batch can implement 1 minute to tens hour.After batching, coiled material temperature is close to often
Wen Shicai can carry out subsequent job, therefore may need longer to batch the time as described above.
In order to obtain while have the hot rolled steel plate of excellent intensity and ductility, such as control is based on shown in the formula (3)
The coiling temperature of alloying component variation, to form fine pearlite tissue.
If coiling temperature is more than A3+ 20 DEG C, coarse pearlite will be formed, yield strength may be caused to reduce, so as to
It is possible that the value of desired yield strength × elongation can not be obtained.Opposite, if coiling temperature is less than A3- 20 DEG C, Jiu Huizao
It is deteriorated into ductility.More specifically, coiling temperature is less than A3At -20 DEG C, although forming fine pearlite and improving yield strength,
But ductility can be deteriorated, it is possible to can not obtain the value of desired yield strength × elongation.Therefore, oiler temperature control exists
When in the temperature range and being cooled down, the hot rolled steel plate to form pearlitic texture can be obtained.
Fig. 2 shows the temperature after the finish to gauge of the hot rolled steel plate manufacturing method of an illustrative embodiments according to the present invention
Degree variation.
More specifically, to finishing temperature (A1- 20 DEG C to A1+ 20 DEG C), intermediate steps temperature (A2- 20 DEG C to A2+20℃)、
And coiling temperature (A3- 20 DEG C to A3+ 20 DEG C) it is controlled according to alloying component, cooling velocity of each step etc. is shown in Fig. 2
Temperature change.Therefore, aforementioned temperature condition and cooling velocity can be confirmed by Fig. 2.
In addition, the hot-rolled steel manufactured by the manufacturing method of an illustrative embodiments according to the present invention
Plate can be utilized directly without carrying out subsequent handling, it is also possible to include the following steps：It batches the plank of the cooling and obtains
Hot rolled steel plate；Later, pickling is carried out to obtained hot rolled steel plate.Moreover, it can also further annealed process wait
Journey.
The final hot rolled steel plate manufactured by the method can be made of pearlite and ausferrite microstructure.Moreover, phase
For the gross score 100% of the hot rolled steel plate microscopic structure, the volume fraction of the ferritic structure can be 75% to 85%,
The volume fraction of pearlitic structrure can be 15% to 25%.At this point, the equiaxial crystal ratio of the ferrite crystal grain can be 0.7 to 1.3.
The yield strength of hot rolled steel plate with the microscopic structure can be 295MPa to 520MPa.Furthermore the hot rolling
The yield strength of steel plate and the value of combination, that is, yield strength × elongation of elongation can be more than 11,500.
In the following, it is described in detail by embodiment.But the following example is only intended to illustrate the present invention, this
The content of invention is not limited to the following example.
Embodiment
In one embodiment of the invention, as the invention steel manufactured by example and compare steel steel billet ingredient it is for example above-mentioned
Shown in table 1.
Then, the steel billet comprising 1 ingredient of table is reheated 200 minutes at 1150 DEG C.
After carrying out roughing to the steel billet of the reheating, in the finishing temperature (A shown in table 2 below1- 20 DEG C to A1+20
DEG C) under implement finish to gauge.
First time cooling is carried out to the plank of the finish to gauge, the centre shown in table 2 below is cooled to the speed of 50 DEG C/s
Temperature (A2- 20 DEG C to A2+20℃).Reach and carry out second with the speed of 5 DEG C/s after the medium temperature and cool down, during cooling
Between be 5 seconds.
The plank of the cooling is cooled to the speed of 50 DEG C/s to the coiling temperature (A shown in table 2 below3- 20 DEG C to A3+
20 DEG C) after batch, so as to obtain hot rolled steel plate.
[table 2]
[table 3]
Using ingredient and the steel billet of compositional range with the table 1, the finishing temperature of the table 2, medium temperature and
Hot rolled steel plate has been manufactured under the conditions of coiling temperature.It, will after microstructure tensile property to final hot rolled steel plate etc. is evaluated
As a result it is shown in the table 3.
The tensile strength of the table 3 refers to the maximum load born before material fracture in tensile test divided by sample
The value of former cross section, the tensile strength are used in aforementioned measure yield strength and elongation to test a machine and testing
Under the conditions of equally measure.In addition to this, therefore the assay method and equipment of yield strength and elongation are as previously mentioned, omit it
It is described in detail.
More specifically, the comparison steel 1 and 2 of the table 1 and the carbon content of an illustrative embodiments according to the present invention
It has differences.More specifically, for the comparative example 1 using comparison steel 1 of institute's carbonaceous component less than 0.1 weight %, it is based on carbon
The solid solution strengthening effect of element is insufficient, therefore pearlite score is also very low, and this point can be confirmed by the table 3.Therefore,
As shown in the table 3, it is known that the value of yield strength × elongation is deteriorated.
For the comparative example 2 using institute's carbonaceous component beyond the comparison steel 2 of 0.2 weight %, it is known that since pearlite is micro-
Tissue excessively generates and elongation is caused to be deteriorated.Therefore, it can be confirmed that the value of yield strength × elongation is also deteriorated.
In addition, the comparison steel 3 and 4 of the table 1 and the manganese content of an illustrative embodiments according to the present invention exist
Difference.More specifically, being less than the comparison steel 3 of 0.5 weight % for contained manganese ingredient, the solution strengthening based on manganese element is not
Foot, therefore pearlite score is low, this point can be confirmed by the comparative example 3 of the table 3.If pearlite score is low, bend
Taking intensity may reduce, it is known that the value of yield strength × elongation of comparative example 3 is deteriorated in the table 3.
For the comparative example 4 using contained manganese ingredient beyond the comparison steel 4 of 1.5 weight %, the finish to gauge as derived from formula (1)
Temperature is too low, therefore can not possibly carry out practical rolling.As a result, can be confirmed can not obtain desired yield strength × elongation
Value.
Furthermore for comparative example 5, it is known that beyond the finishing temperature range as derived from formula (1).More specifically, with the ratio
Compared with as example 5, if beyond the finishing temperature range as derived from formula (1), as yield strength declines, yield strength × elongation
The value of rate is deteriorated.
For comparative example 6 and 7, it is known that intermediate steps temperature range exceeds one according to the present invention as derived from formula (2)
The range of illustrative embodiments.
Therefore, for the comparative example 6 and 7, it is known that as elongation declines, the value of yield strength × elongation is deteriorated.
In addition, for comparative example 8 and 9, it is known that coiling temperature range exceeds one according to the present invention as derived from formula (3)
The range of illustrative embodiments.
More specifically, the comparative example 8 for the coiling temperature range as derived from formula (3) can not be met, it is known that intensity is deteriorated,
And for comparative example 9, elongation is deteriorated.Therefore, for the comparative example 8 and 9, it is known that the value of yield strength × elongation becomes
Difference.
Comparative example 10 and 11 is the situation manufactured by manufacturing processes customary, is presented from finishing temperature continuous coo1ing to volume
Take temperature and without the situation of intermediate steps temperature.
As a result, the comparative example 10 and 11 can not meet the ferrite of an illustrative embodiments according to the present invention
The range of equiaxial crystal ratio, it is known that ductility is deteriorated.Moreover, understand that the value of yield strength × elongation is deteriorated.
Compositing range conversely, for an illustrative embodiments according to the present invention and the hot rolling item as derived from formula
The example 1 to 2 that part is all satisfied can be confirmed with excellent yield strength and elongation.
Fig. 1 is shown derived from yield strength and elongation and yield strength × elongation as example and comparative example
Value.
More specifically, square part represents the value of comparative example 1 to 11 in Fig. 1, circular portion represents the value of example 1 and 2.
Therefore, as shown in Figure 1, example 1 and 2 has excellent intensity and ductility.More specifically, for the example 1 and 2,
The value of yield strength × elongation is more than 11500, therefore including in gray area.
The embodiment of the present invention is illustrated, but those skilled in the art is appreciated that above by reference to attached drawing
In the case where not changing technological thought and essential feature, the present invention can be implemented with other specific embodiments.
Therefore, above-described embodiment is only exemplary not restricted.Protection scope of the present invention should be with claim
Subject to book rather than above description, have altered or change as derived from the meaning, range and such equivalents of claims
Form is all fallen in protection scope of the present invention.
Claims (18)
1. a kind of hot rolled steel plate wherein relative to the total 100 weight % of hot rolled steel plate, consists of the following compositions：C：0.1 weight % is extremely
0.2 weight %, Si：Below 0.5 weight % and not comprising 0 weight %, Mn：0.5 weight % to 1.5 weight %, P：0.03 weight
Measure below % and not comprising 0 weight %, S：Below 0.015 weight % and not comprising 0 weight %, Al：Below 0.05 weight % and
Not comprising 0 weight %, N：Below 0.01 weight % and not comprising 0 weight %, surplus are Fe and other inevitable impurity,
The hot rolled steel plate is made of pearlite and ausferrite microstructure,
Relative to the gross score 100% of the hot rolled steel plate microscopic structure, the volume fraction of the ferritic structure for 75% to
85%, and the equiaxial crystal ratio of the ausferrite microstructure is 0.7 to 1.3.
2. hot rolled steel plate according to claim 1, wherein,
Other inevitable impurity include Cr：Below 0.3 weight % and not comprising 0 weight %, Ni：0.3 weight % with
Down and not comprising 0 weight %, Mo：Below 0.2 weight % and not comprising 0 weight %, Cu：Below 0.1 weight % and not comprising 0 weight
Measure %.
3. hot rolled steel plate according to claim 2, wherein,
Relative to the gross score 100% of the hot rolled steel plate microscopic structure, the volume fraction of the pearlitic structrure for 15% to
25%.
4. hot rolled steel plate according to claim 3, wherein,
The yield strength of the hot rolled steel plate is 295MPa to 520MPa.
5. hot rolled steel plate according to claim 4, wherein,
The value of yield strength × elongation of the hot rolled steel plate is more than 11,500MPa% and below 17,500MPa%.
6. a kind of hot rolled steel plate manufacturing method, includes the following steps：
Prepare steel billet, relative to 100 total weight %, the steel billet consists of the following compositions：C：0.1 weight % to 0.2 weight
Measure %, Si：Below 0.5 weight % and not comprising 0 weight %, Mn：0.5 weight % to 1.5 weight %, P：Below 0.03 weight %
And not comprising 0 weight %, S：Below 0.015 weight % and not comprising 0 weight %, Al：Below 0.05 weight % and not comprising 0 weight
Measure %, N：Below 0.01 weight % and not comprising 0 weight %, surplus is Fe and other inevitable impurity；
The steel billet is reheated at 1100 DEG C to 1300 DEG C；
Roughing is carried out to the steel billet of the reheating；
Finish to gauge is carried out to the steel billet of the roughing；
The plank of the finish to gauge is cooled down；And
It batches the plank of the cooling and obtains hot rolled steel plate,
Wherein, in the step of carrying out finish to gauge to the steel billet of the roughing, the finish to gauge is in A1- 20 DEG C to A1+ 20 DEG C of temperature
In the range of implement,
A1=932.1-392.8 [C] -61.9 [Mn]+43.9 [Si]+420.6 [P]+220.0 [Al] -15.5 [Cr] -15.2 [Ni]+
31.5 [Mo] -20 [Cu] --- --- --- --- --- --- ----formulas (1)
In formula (1), [C], [Mn], [Si], [P], [Al], [Cr], [Ni], [Mo] and [Cu] represents respective component content
Weight %；
Wherein, the step of being cooled down to the plank of the finish to gauge, includes the following steps：
First time cooling is carried out with the speed of 40 DEG C/s to 60 DEG C/s to the plank of the finish to gauge；And the first time is cooled down
Plank carry out second with the speed of 1 DEG C/s to 8 DEG C/s and cool down；
Wherein, in the step of with the speed of 40 DEG C/s to 60 DEG C/s cool down for the first time to the plank of the finish to gauge, by institute
The plank for stating finish to gauge is cooled to A2- 20 DEG C to A2+ 20 DEG C of temperature range,
A2=740.1-35.4 [C] -64.5 [Mn]+29.1 [Si]+16.9 [Cr] -16.9 [Ni] --- --- -- formulas (2)
In formula (2), [C], [Mn], [Si], [Cr] and [Ni] represents the weight % of respective component content；
Wherein, in by batching the plank of the cooling and the step of obtaining hot rolled steel plate, the plank is cooled to A3-20
DEG C to A3It is batched after+20 DEG C of temperature range,
A3=693.4-444.5 [C] -80.5 [Mn] -35.0 [Si] -76.0 [Cr] -35.0 [Ni] -85.7 [Mo] -- formula (3)
In formula (3), [C], [Mn], [Si], [Cr], [Ni] and [Mo] represents the weight % of respective component content.
7. hot rolled steel plate manufacturing method according to claim 6, wherein,
Other inevitable impurity include Cr：Below 0.3 weight % and not comprising 0 weight %, Ni：0.3 weight % with
Down and not comprising 0 weight %, Mo：Below 0.2 weight % and not comprising 0 weight %, Cu：Below 0.1 weight % and not comprising 0 weight
Measure %.
8. hot rolled steel plate manufacturing method according to claim 6 carries out the step of finish to gauge by the steel billet to the roughing
Suddenly, the austenitic microstructure for making the steel billet of the finish to gauge that there is size to be 10 μm to 40 μm.
9. hot rolled steel plate manufacturing method according to claim 6, wherein,
In the step of plank cooled down to the first time with the speed of 1 DEG C/s to 8 DEG C/s cool down for second, described the
The plank once cooled down is cooled 1 second to 8 seconds.
10. hot rolled steel plate manufacturing method according to claim 9, the step cooled down by the plank to the finish to gauge
It is rapid to form isometric ferrite structure.
11. hot rolled steel plate manufacturing method according to claim 10, is cooled down by the plank to the finish to gauge
Step makes the plank have 75% to 85% isometric ferritic structure and 15% relative to microscopic structure gross score 100%
To 25% austenite structure.
12. hot rolled steel plate manufacturing method according to claim 6, wherein,
In the step of hot rolled steel plate being obtained batching the plank of the cooling,
The plank is batched after being cooled down with the speed of 40 DEG C/s to 60 DEG C/s.
13. hot rolled steel plate manufacturing method according to claim 7, wherein,
In the step of being reheated at 1100 DEG C to 1300 DEG C to the steel billet,
The steel billet is reheated 100 minutes to 400 minutes.
14. hot rolled steel plate manufacturing method according to claim 7, further comprising the steps of：
Hot rolled steel plate is obtained batching the plank of the cooling；
Pickling is carried out to obtained hot rolled steel plate.
15. the hot rolled steel plate manufacturing method described in any one in claim 6 to 14, wherein,
The hot rolled steel plate is made of pearlite and ausferrite microstructure, and relative to the total of the hot rolled steel plate microscopic structure
Score 100%, the volume fraction of the ferritic structure is 75% to 85%.
16. the hot rolled steel plate manufacturing method described in any one in claim 6 to 14, wherein,
Relative to the gross score 100% of the hot rolled steel plate microscopic structure, the volume fraction of pearlitic structrure is 15% to 25%.
17. the hot rolled steel plate manufacturing method described in any one in claim 6 to 14, wherein,
The yield strength of the hot rolled steel plate is 295MPa to 520MPa.
18. the hot rolled steel plate manufacturing method described in any one in claim 6 to 14, wherein,
The value of yield strength × elongation of the hot rolled steel plate is more than 11,500MPa% and below 17,500MPa%.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1020150123843A KR101664098B1 (en) | 2015-09-01 | 2015-09-01 | Hot rolled steel sheet for pressure vessel, and the method of manufacturing the same |
| KR10-2015-0123843 | 2015-09-01 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN106480355A CN106480355A (en) | 2017-03-08 |
| CN106480355B true CN106480355B (en) | 2018-06-26 |
Family
ID=57145669
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510885586.9A Expired - Fee Related CN106480355B (en) | 2015-09-01 | 2015-12-04 | Pressure vessel hot rolled steel plate and its manufacturing method |
Country Status (2)
| Country | Link |
|---|---|
| KR (1) | KR101664098B1 (en) |
| CN (1) | CN106480355B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR102031460B1 (en) * | 2017-12-26 | 2019-10-11 | 주식회사 포스코 | Hot rolled steel with excellent impact toughness, steel tube, steel member, and method for manufacturing thereof |
| KR102296840B1 (en) * | 2019-12-16 | 2021-09-01 | 주식회사 포스코 | High strength steel material having excellent ductility and manufacturing method for the same |
| KR102348664B1 (en) * | 2019-12-18 | 2022-01-06 | 주식회사 포스코 | Steel for vacuum tube and manufacturing method for the same |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4018318B2 (en) * | 2000-04-18 | 2007-12-05 | 株式会社神戸製鋼所 | Steel plate manufacturing method with excellent brittle cracking characteristics |
| WO2002044436A1 (en) * | 2000-12-01 | 2002-06-06 | Posco | Steel plate to be precipitating tin+mns for welded structures, method for manufacturing the same and welding fabric using the same |
| JP4367091B2 (en) * | 2002-12-20 | 2009-11-18 | Ｊｆｅスチール株式会社 | High-strength hot-rolled steel sheet having excellent fatigue resistance and excellent strength-ductility balance and method for producing the same |
| JP4404004B2 (en) * | 2005-05-11 | 2010-01-27 | 住友金属工業株式会社 | High-tensile hot-rolled steel sheet and manufacturing method thereof |
| US9453269B2 (en) * | 2011-04-13 | 2016-09-27 | Nippon Steel & Sumitomo Metal Corporation | Hot-rolled steel sheet for gas nitrocarburizing and manufacturing method thereof |
| JP6058439B2 (en) * | 2013-01-10 | 2017-01-11 | 株式会社神戸製鋼所 | Hot-rolled steel sheet with excellent cold workability and surface hardness after processing |
| KR101560944B1 (en) * | 2013-12-24 | 2015-10-15 | 주식회사 포스코 | High strength hot rolled steel sheet having excellent surface property and method for manufacturing the same |
-
2015
- 2015-09-01 KR KR1020150123843A patent/KR101664098B1/en active IP Right Grant
- 2015-12-04 CN CN201510885586.9A patent/CN106480355B/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CN106480355A (en) | 2017-03-08 |
| KR101664098B1 (en) | 2016-10-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US10577671B2 (en) | High-hardness hot-rolled steel product, and a method of manufacturing the same | |
| KR101677396B1 (en) | Ultra high strength steel sheet having excellent formability and expandability, and method for manufacturing the same | |
| JP6762415B2 (en) | Hot forming member with excellent crack propagation resistance and ductility, and its manufacturing method | |
| US7794552B2 (en) | Method of producing austenitic iron/carbon/manganese steel sheets having very high strength and elongation characteristics and excellent homogeneity | |
| US10597760B2 (en) | High-strength steel material for oil well and oil well pipes | |
| JP6048626B1 (en) | Thick, high toughness, high strength steel plate and method for producing the same | |
| CN105671447B (en) | The excellent high yield of hole expandability is than type high strength cold rolled steel plate and its manufacture method | |
| CN110073024B (en) | Ultrahigh-strength steel sheet having excellent bending workability and method for producing same | |
| US9863022B2 (en) | High-strength ultra-thick H-beam steel | |
| CN109072387B (en) | Ultra-high strength and high ductility steel sheet having excellent yield ratio and method for producing same | |
| JP6819198B2 (en) | Rolled bar for cold forged tempered products | |
| CN103805869A (en) | High-strength hot-rolled Q and P steel and manufacturing method thereof | |
| CN103380217A (en) | Hot rolled flat steel product produced from a complex phase steel, and method for producing same | |
| JP6818147B2 (en) | High-strength, high-toughness thick steel sheet and its manufacturing method | |
| US11466336B2 (en) | High-strength steel sheet having excellent burring workability in low temperature range and manufacturing method therefor | |
| CN108368593A (en) | High strength steel and its manufacturing method with excellent low temperature strain-aging impact characteristics | |
| CN106480355B (en) | Pressure vessel hot rolled steel plate and its manufacturing method | |
| US11098394B2 (en) | Rolled wire rod | |
| CN114080463B (en) | High-strength steel sheet and method for producing same | |
| JP2002363685A (en) | Low yield ratio high strength cold rolled steel sheet | |
| KR20230048109A (en) | Steel forged parts and manufacturing method thereof | |
| EP3708691A1 (en) | Ultrahigh-strength and high-ductility steel sheet having excellent cold formability, and manufacturing method therefor | |
| KR20180048525A (en) | Pressure vessel, and the method of manufacturing the same | |
| CN104213016B (en) | Ship inner panel high-strength steel and production method thereof | |
| KR20170056353A (en) | Pressure vessel, and the method of manufacturing the same |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20180626 Termination date: 20201204 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |