CN106583449A - Rolling method of ferritic stainless steel - Google Patents

Rolling method of ferritic stainless steel Download PDF

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Publication number
CN106583449A
CN106583449A CN201611200388.5A CN201611200388A CN106583449A CN 106583449 A CN106583449 A CN 106583449A CN 201611200388 A CN201611200388 A CN 201611200388A CN 106583449 A CN106583449 A CN 106583449A
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CN
China
Prior art keywords
rolling
deformation rate
annealing
stainless steel
cold
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN201611200388.5A
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Chinese (zh)
Inventor
杨永超
白晋钢
杨永杰
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shanxi Taigang Stainless Steel Co Ltd
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Shanxi Taigang Stainless Steel Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Shanxi Taigang Stainless Steel Co Ltd filed Critical Shanxi Taigang Stainless Steel Co Ltd
Priority to CN201611200388.5A priority Critical patent/CN106583449A/en
Publication of CN106583449A publication Critical patent/CN106583449A/en
Pending legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
    • B21B1/22—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length
    • B21B1/24—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length in a continuous or semi-continuous process
    • B21B1/28—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length in a continuous or semi-continuous process by cold-rolling, e.g. Steckel cold mill
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
    • B21B37/46—Roll speed or drive motor control
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
    • B21B37/56—Elongation control
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/26—Methods of annealing
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/52—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/001—Ferrous alloys, e.g. steel alloys containing N
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
    • B21B1/22—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length
    • B21B2001/221—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length by cold-rolling
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/005—Ferrite

Abstract

The invention relates to a rolling method of ferritic stainless steel. According to the method, firstly, the ferritic stainless steel to be rolled comprises, by weight, 0-0.030% of C, 0-1.00% of Si, 0-1.00% of Mn, 0-0.040% of P, 0-0.030% of S, 11-13.5% of Cr, 0-0.60% of Ni, 0-0.030% of N and the balance Fe and inevitable impurities; secondly, the annealing mode of hot-rolling steel reels is online annealing, the annealing temperature is 820-850 DEG C, and the wire passing speed is 40-60 m/min; thirdly, after annealing is completed, acid pickling is conducted through a hydrochloric acid and nitric acid mixed solution; and fourthly, cold rolling is conducted by five passes, the total deformation rate of cold rolling is 60-80%, the deformation rate of a 1# rolling machine is 25-30%, the deformation rate of a 2# rolling machine is 21-26%, the deformation rate of a 3# rolling machine is 18-23%, the deformation rate of a 4# rolling machine is 15-20%, the deformation rate of a 5# rolling machine is 12-17%, and the rolling speed is 80-110 m/min. According to the rolling method of ferritic stainless steel, rolling of cold continuous rolling lines is stable, and the elongation percentage of finished cold rolled plates reaches 32.2%.

Description

A kind of method of ferrite stainless steel rolling
Technical field
The present invention relates to a kind of stainless milling method, and in particular to a kind of method of ferrite stainless steel rolling.
Background technology
Ferritic stainless steel is the excellent economical rustless steel of a cheap class, atmospheric corrosion resistance and polishing machine.It is former Production technology is rolled using single chassis, and rolling is smooth, and plate shape is good, but low production efficiency.This is rolled in the examination of continuous rolling production line When planting rustless steel, there is serious broken belt accident.Broken belt accident can cause production line stop, lumber recovery to decline.
The content of the invention
In order to overcome the above-mentioned deficiency of the method for existing ferrite stainless steel rolling, the present invention to provide a kind of rustless steel cold company Rolling line rolling is steady, finished product cold-reduced sheet elongation percentage reaches 32.2%, and performance meets the side of the ferrite stainless steel rolling of national standard Method.
The percentage by weight of ferrite stainless composition of steel of the present invention is：
C≤0.030%, Si≤1.00%, Mn≤1.00%, P≤0.040%, S≤0.030%, Cr 11 ~ 13.5%, Ni≤0.60%, N ≤ 0.030%, and C, Si, Mn, P, S, Ni, N are both greater than zero；
Remaining is Fe and inevitable impurity.
The principle of institute's foundation of the present invention is：During continuous rolling, coil of strip is successively via five mill millings；If in front and back Coil of strip performance difference is big, and the change of the uneven thickness of coil of strip, thickness can be caused during rolling will cause rolling mill screwdown, speed, tension force , easily there is broken belt in high-speed rolling in generation saltus step.Therefore, the continuous rolling of cold continuous rolling is realized, except to ensure that raw material does not have Outside defect, good weldquality, it is necessary to ensure the stability of coil of strip mechanical property after annealing.By optimizing continuous annealing line Annealing process, selects rational annealing temperature and temperature retention time, it is ensured that coil of strip has good metallographic microstructure and mechanical property Can, and by furnace temperature precise control, reduce the fluctuation of annealing temperature, it is ensured that coil of strip performance is stablized.
The present invention selects on-line continuous annealing when being and annealing by hot-rolled black-skin volume, it is determined that suitable annealing temperature and insulation Time, it is ensured that the stability of performance after coil annealing；Continuous rolling is selected when cold rolling, deformation rate and the rolling of each frame is determined Speed, reaches the purpose of steady rolling during tandem rolling.
The present invention ferrite stainless steel rolling method include it is following successively the step of：
The percentage by weight of the composition of I ferrite stainless steel rolling is：
C≤0.030%, Si≤1.00%, Mn≤1.00%, P≤0.040%, S≤0.030%, Cr 11 ~ 13.5%, Ni≤ 0.60%, N≤0.030%, and C, Si, Mn, P, S, Ni, N are both greater than zero；
Remaining is Fe and inevitable impurity.
II coils of hot-rolled steel raw material annealing way is online annealing, and annealing temperature is 820 DEG C ~ 850 DEG C, crosses wire velocity control In 40 ~ 60m/min.
In hydrochloric acid and nitric acid mixed liquor pickling after III annealing.
The present invention is enhancing effect of rolling, the deformation rate and mill speed of controlled rolling.
IV cold rolling five passage, cold rolling total deformation rate is 60% ~ 80%, and each milling train deformation rate is respectively 1# milling trains 25% ~ 30%, 2# Milling train 21% ~ 26%, 3# milling trains 18% ~ 23%, 4# milling trains 15% ~ 20%, 5# milling trains 12% ~ 17%, mill speed is 80 ~ 110m/min. And the deformation rate of each milling train, is sequentially reduced from front to back.
For ease of operation, in step IV, each milling train deformation rate is respectively 1# milling trains 25% ~ 30%, 2# milling trains 21% ~ 24%, 3# Milling train 18% ~ 20%, 4# milling trains 15% ~ 17%, 5# milling trains 12% ~ 14%.
To check effect of rolling, finished product cold drawing performance is tested.
V cold drawing performance
Yield strength/Mpa 260-310, tensile strength/Mpa 490-550, elongation percentage/% 25-34, hardness HV 130- 145, it is qualified to bend.
Beneficial effects of the present invention
According to the milling method of the present invention, hot-rolled black-skin is rolled up Jing after continuous annealing pickling, is realized in rustless steel cold continuous rolling line steady Rolling, the finished product cold-reduced sheet elongation percentage of production reaches 32.2%, and excellent performance complies with the national standard requirements（≥22%）.Reduce Labor intensity, improve production efficiency.
Specific embodiment
The specific embodiment of the present invention, but the specific embodiment of the present invention not office are described in detail with reference to embodiment It is limited to following embodiments.
Embodiment one
The percentage by weight of the composition of I ferrite stainless steel rolling is：
C：0.013%, Si：0.34%, Mn：0.26%, P：0.021 %, S：0.004%, Cr：11.9%, Ni：0.04%, N： 0.017%, remaining is Fe and inevitable impurity.
II hot rolling volume specification is 3.0mm, and continuous annealing plate temperature temperature is 840 DEG C, crosses linear velocity 45m/min.
In hydrochloric acid and nitric acid mixed liquor pickling after III annealing.
IV hot rolling volume specification is 3.0mm, and finished product cold drawing specification is 0.8mm, and cold rolling total deformation rate is 73.33%, and each milling train becomes Form quotient is respectively 1# milling trains 28.6%, 2# milling trains 24.5%, 3# milling trains 20.6%, 4# milling trains 16.3%, 5# milling trains 14.7%, rolling speed Degree 90m/min.
The V tandem rolling line operation of rolling is steady, and cold drawing bounce amplitude is not more than 0.05 millimeter, and broken belt, end properties symbol do not occur Requirement of the national standard elongation percentage more than 22% is closed, end properties parameter is as follows：
Yield strength/Mpa 289, tensile strength/Mpa 523, elongation percentage/% 31, hardness HV 136/136/137, bending is closed Lattice.
Embodiment two
The percentage by weight of the composition of I ferrite stainless steel rolling is：
C：0.014%, Si：0.30%, Mn：0.24%, P：0.019 %, S：0.003%,
Cr：12.2%, Ni：0.04%, N：0.016%, remaining is Fe and inevitable impurity.
II hot rolling volume specification is 3.0mm, and continuous annealing plate temperature temperature is 840 DEG C, crosses linear velocity 45m/min.
In hydrochloric acid and nitric acid mixed liquor pickling after III annealing.
IV hot rolling volume specification is 3.0mm, and finished product cold drawing specification is 1.0mm, and cold rolling total deformation rate is 66.67%, and each milling train becomes Form quotient is respectively 1# milling trains 28.2%, 2# milling trains 24.2%, 3# milling trains 19.1%, 4# milling trains 15.5%, 5# milling trains 12.8%, rolling speed Degree 96m/min.
The V tandem rolling line operation of rolling is steady, and cold drawing bounce amplitude is not more than 0.05 millimeter, and broken belt, end properties symbol do not occur Requirement of the national standard elongation percentage more than 22% is closed, end properties parameter is as follows：
Yield strength/Mpa 295, tensile strength/Mpa 519, elongation percentage/% 29, hardness HV 139/139/140, bending is closed Lattice.

Claims (2)

1. a kind of method of ferrite stainless steel rolling, it include it is following successively the step of：
The percentage by weight of the composition of I ferrite stainless steel rolling is：
C≤0.030%, Si≤1.00%, Mn≤1.00%, P≤0.040%, S≤0.030%, Cr 11 ~ 13.5%, Ni≤ 0.60%, N≤0.030%, and C, Si, Mn, P, S, Ni, N are both greater than zero；Remaining is Fe and inevitable impurity；
II coils of hot-rolled steel raw material annealing way is online annealing, and annealing temperature is 820 DEG C ~ 850 DEG C, cross wire velocity control 40 ~ 60m/min；
In hydrochloric acid and nitric acid mixed liquor pickling after III annealing；
IV cold rolling five passage, cold rolling total deformation rate is 60% ~ 80%, and each milling train deformation rate is respectively 1# milling trains 25% ~ 30%, 2# and rolls Machine 21% ~ 26%, 3# milling trains 18% ~ 23%, 4# milling trains 15% ~ 20%, 5# milling trains 12% ~ 17%, mill speed is 80 ~ 110m/min, and And the deformation rate of each milling train, it is sequentially reduced from front to back.
2. the method for ferrite stainless steel rolling according to claim 1, is characterized in that：Also carry out cold drawing service check；
V cold drawing performance
Yield strength/Mpa 260-310, tensile strength/Mpa 490-550, elongation percentage/% 25-34, hardness HV 130- 145, it is qualified to bend.
CN201611200388.5A 2016-12-22 2016-12-22 Rolling method of ferritic stainless steel Pending CN106583449A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
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Application Number Priority Date Filing Date Title
CN201611200388.5A CN106583449A (en) 2016-12-22 2016-12-22 Rolling method of ferritic stainless steel

Publications (1)

Publication Number Publication Date
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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108856289A (en) * 2018-06-01 2018-11-23 山西太钢不锈钢股份有限公司 Middle chrome ferritic stainless steel cold rolled strip steel production method
CN110238193A (en) * 2019-06-21 2019-09-17 山西太钢不锈钢精密带钢有限公司 Ultra-thin ultra-wide rolling stainless steel band technique
CN112474817A (en) * 2020-11-16 2021-03-12 山西太钢不锈钢股份有限公司 Method for controlling surface short wiping white mark defects of 430-series thick cold plate
CN114015846A (en) * 2021-10-19 2022-02-08 山西太钢不锈钢股份有限公司 Process method for reducing yield strength of low-chromium ferrite stainless steel
CN115044826A (en) * 2022-05-07 2022-09-13 广西柳州钢铁集团有限公司 410 ferritic stainless steel

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102251250A (en) * 2010-05-18 2011-11-23 宝山钢铁股份有限公司 Rolling method for pickling line thermal annealing of low-chromium 400 series stainless steel
CN102989771A (en) * 2011-09-19 2013-03-27 宝山钢铁股份有限公司 Low-chromium ferritic stainless steel cold continuous rolling manufacturing method
CN105132819A (en) * 2015-08-13 2015-12-09 山西太钢不锈钢股份有限公司 Continuous rolling method of low-chromium ferrite stainless steel
CN106140813A (en) * 2015-03-24 2016-11-23 宝钢不锈钢有限公司 The cold rolling production method of chrome ferritic stainless steel in a kind of automobile exhaust system
CN106180184A (en) * 2016-07-11 2016-12-07 山西太钢不锈钢股份有限公司 A kind of milling method of austenite stainless steel plate

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102251250A (en) * 2010-05-18 2011-11-23 宝山钢铁股份有限公司 Rolling method for pickling line thermal annealing of low-chromium 400 series stainless steel
CN102989771A (en) * 2011-09-19 2013-03-27 宝山钢铁股份有限公司 Low-chromium ferritic stainless steel cold continuous rolling manufacturing method
CN106140813A (en) * 2015-03-24 2016-11-23 宝钢不锈钢有限公司 The cold rolling production method of chrome ferritic stainless steel in a kind of automobile exhaust system
CN105132819A (en) * 2015-08-13 2015-12-09 山西太钢不锈钢股份有限公司 Continuous rolling method of low-chromium ferrite stainless steel
CN106180184A (en) * 2016-07-11 2016-12-07 山西太钢不锈钢股份有限公司 A kind of milling method of austenite stainless steel plate

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108856289A (en) * 2018-06-01 2018-11-23 山西太钢不锈钢股份有限公司 Middle chrome ferritic stainless steel cold rolled strip steel production method
CN110238193A (en) * 2019-06-21 2019-09-17 山西太钢不锈钢精密带钢有限公司 Ultra-thin ultra-wide rolling stainless steel band technique
CN110238193B (en) * 2019-06-21 2020-12-08 山西太钢不锈钢精密带钢有限公司 Ultra-thin ultra-wide stainless steel band rolling process
CN112474817A (en) * 2020-11-16 2021-03-12 山西太钢不锈钢股份有限公司 Method for controlling surface short wiping white mark defects of 430-series thick cold plate
CN114015846A (en) * 2021-10-19 2022-02-08 山西太钢不锈钢股份有限公司 Process method for reducing yield strength of low-chromium ferrite stainless steel
CN115044826A (en) * 2022-05-07 2022-09-13 广西柳州钢铁集团有限公司 410 ferritic stainless steel
CN115044826B (en) * 2022-05-07 2023-09-15 广西柳州钢铁集团有限公司 410 ferrite stainless steel

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