CN100366777C - High-temperature creep resistant furnace shell material and preparation method thereof - Google Patents
High-temperature creep resistant furnace shell material and preparation method thereof Download PDFInfo
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Abstract
The invention belongs to the field of metallurgy, and particularly relates to steel for a metallurgical furnace shell. The high-temperature creep resistant furnace shell material comprises the following specific chemical components in percentage by weight: 0.04 to 0.20 percent of C, 0.60 to 2.00 percent of Mn, less than or equal to 0.8 percent of Si, 0.01 to 0.20 percent of W, 0.01 to 0.10 percent of Mo, 0.01 to 0.05 percent of V, 0.01 to 0.05 percent of Ti0.01 to 0.05 percent of Nb, 0.02 to 0.08 percent of N, 0.03 to 0.10 percent of Ce, 0.01 to 0.07 percent of Al, 0 to 0.08 percent of Mg, 0 to 0.08 percent of Ca, 0.01 to 0.05 percent of Zr, 0.001 to 0.004 percent of B, less than or equal to 0.01 percent of S, less than or equal to 0.02 percent of P, and the balance of Fe. Wherein 2Mo + W is more than or equal to 0.16 percent and less than or equal to 0.40 percent, V + Ti is more than or equal to 0.03 percent and less than or equal to 0.08 percent, and Mg + Ca is more than or equal to 0.03 percent and less than or equal to 0.10 percent. The manufacturing method comprises the process steps of smelting, casting and rolling. The smelting comprises smelting in a steel furnace and refining outside the furnace, the steel is cast in a slab caster for continuous casting, and after the casting, the slab is hot-rolled and then is subjected to normalizing treatment. The furnace shell material manufactured by the invention is used for large-scale converters, has the advantages of good welding performance, good high-temperature creep resistance and the like, can obviously reduce the deformation of the furnace shell, prolongs the service life of the furnace shell, and has good economic benefit.
Description
Technical field:
The invention belongs to field of metallurgy, particularly metallurgical furnace furnace shell steel.
Background technology:
Development along with steel-smelting technology, rhythm of production is constantly accelerated, the molten steel tapping temperature raises, the magnesia carbon brick of high thermal conductivity is extensive use of in addition, cause the rising of converter and other metallurgical furnace shell temperature, cause metallurgical furnace, particularly the furnace shell creep strain has appearred in converter to some extent, causes furnace shell shortening in work-ing life.
In the prior art,, prolong the work-ing life of metallurgical furnace furnace shell, adopted two kinds of different technological lines in the world for improving metallurgical furnace furnace shell creep strain drag: the one, strengthen cooling conditions to furnace shell, reduce the furnace shell working temperature, prevent shell deformation; The 2nd, the metallurgical furnace furnace shell steel of development creep-resistant property excellence.
Strengthening the cooling conditions of metallurgical furnace furnace shell, reduce the furnace shell working temperature, is the important means that solves shell deformation, along with the reduction of casing temperature, can suppress the distortion of furnace shell effectively.Chinese patent CN2548097 discloses converter shell force air refrigerating unit, and this device comprises blower fan, air intake passage, backing ring, air-cooled house steward, water cooler and corresponding pipeline.Cold wind directly is sprayed onto furnace shell in appearance through water cooler, and the metallurgical furnace furnace shell is directly carried out the vertical shower cooling of cold wind.Because the cooling ratio of vertical shower cooling is traditional simple air-cooled about 5 times, so can improve the cooling performance of metallurgical furnace furnace shell greatly, effectively reduce the too high working temperature of metallurgical furnace furnace shell, reach and slow down shell deformation, effectively prolong the metallurgical furnace furnace shell purpose in work-ing life.But this apparatus structure complexity, not only facility investment is big, and difficult in maintenance.In addition, answer the requirement of Britain iron and steel affiliated company, Britain wears dimension metallurgical equipment company and has developed the Hi-vap cooling technology, and first the Hi-vap cooling technology was applied to No. 1 converter (315t) of Ying Gang connection Scunthorpe United factory in 1989, this technology has obviously reduced the furnace shell working temperature, prolonged converter shell (Goodman N J and Brown D.Development of the Hi-vap BOF cooling system in work-ing life, Iron and Steel Engineer, 1993,70 (11): 52-55).Its weak point is equipment and technical sophistication, and investment is big.
Improving on the metallurgical furnace furnace shell cooling conditions basis, further improve furnace shell material resistance toheat, particularly improve furnace shell material heat resistanceheat resistant creep property, also be to alleviate shell deformation, improve the important measures in furnace shell life-span.For this reason, many producers have carried out the research of shell steel new steel grade.Japanese Patent JP11291085-A discloses a kind of high-strength ferritic steel with good high temperature creep-resisting, its concrete chemistry (wt%) composed as follows: 0.03-0.12C, 0.03-1.00Si, 0.5-3.0Mn, 8.0-13.0Cr, 1.5-2.5W, 0.05-0.35V, 0.01-0.15Ti, 0.02-0.06N, 0.20-1.00Ta or 0.05-2.0Hf,＜0.1Ni,＜0.005B,＜0.015P and S,＜0.010O, surplus is Fe.This material increases the production cost of steel owing to contain more chromium and tungsten.Japanese Patent JP2004107719-A also discloses a kind of high temperature creep-resisting multi-element low alloy high temperature steel, and its concrete chemical constitution (weight %) is as follows: 0.03-0.1C,＜0.1Si, 0.001-0.3Mn,＜0.02P,＜0.008S, 0.4-1.5Cr, 0.25-1Mo, 0.03-0.15V, 0.001-0.07Nb, 0.001-0.3Ni, 0.001-0.02Ti, 0.0001-0.006B, 0.0001-0.03Nd,＜0.01Al,＜0.006N,＜0.005O, surplus is Fe.Contain more expensive molybdenum in this material, when being used to prepare furnace shell, the furnace shell cost is increased.Chinese invention patent CN1414130 discloses a kind of high temperature creep property and flexible Fe-Cr-Ni base casting alloy composition and manufacture method thereof taken into account, and its chemical ingredients (wt%) is: 0.03-0.2C; 0.1-1.0Si; 0.2-1.2Mn; 20-23Cr; 30-35Ni; 0.8-1.2Nb; 0.02-0.3Zr; 0.03-0.3Ti; 0.01-0.2RE RE is one or more among La, Y or the Ce; Surplus is Fe and unavoidable impurities.This invention can form with it that complicated (Zr) C and be that macroscopic view, the microtexture of tiny, disperse distribution carbide and dense structure is feature has good high-temperature creep resistance, thermal shock resistance and good toughness for Nb, Ti.The hot wall collecting tubule and the inside and outside various parts that need under excellent toughness and the hot operation condition of stove that can be used for converter.Owing to contain more expensive nickel, Chrome metal powder, it is too high to be used to prepare the furnace shell cost.The large converter shell common used material has structural low such as 16MnR, SM400C and SM400ZL (Wang Longshou, the new technology application during 300 tons of converter shells of Baosteel are changed, bao steel technology, 2001 (5): 48～50) at present.They have higher intensity, welding property and resistance to cracking energy preferably, but the poor-performing of its heat resistanceheat resistant creep.In the use, the thermo-creep deformation of furnace shell material is bigger.
Summary of the invention:
The object of the present invention is to provide a kind of creep resistant deforming excellent performance, can significantly improve the high temperature creep-resisting furnace shell material in metallurgical furnace furnace shell work-ing life and preparation method thereof.
Because the metallurgical furnace furnace shell generally is long term operation under 280～470 ℃ temperature and bigger thermal stresses effect, serious creep strain and material capability easily take place final furnace shell worsens.For satisfying the furnace shell bad working environment, furnace shell material should possess following requirement: 1, should possess good anti-creep behavior deformation; 2, should have higher high temperature strength; 3, should use initial stage toughness height, the embrittlement rate is low in the use; 4, should have good welding property.Has good use properties in order to ensure the metallurgical furnace furnace shell, satisfy its long-life requirement, according to modern low alloy steel microalloying theory, high temperature creep-resisting furnace shell material of the present invention on C-Mn alloy system basis, added Ce, Nb, N, Al, Zr, B, V and Ti and Ca and (or) microalloy element such as Mg, reach multielement enhanced purpose, added a certain amount of Mo and W for improving its heat resistance simultaneously.Adopt controlled rolling and normalizing treatment technology on the technology, guaranteed the refinement and the uniform distribution of thick cross section ferrite crystal grain tissue, further improved yield strength and toughness.
At above-mentioned purpose, the concrete chemical ingredients (weight %) of a kind of high temperature creep-resisting furnace shell material of the present invention is: C 0.04～0.20%, Mn 0.60～2.00%, Si≤0.8%, and W 0.01～0.20%, Mo0.01～0.10%, V 0.01～0.05%, and Ti 0.01～0.05%, and Nb 0.01～0.05%, N 0.02～0.08%, Ce 0.03～0.10%, and Al 0.01～0.07%, and Mg 0～0.08%, Ca 0～0.08%, Zr0.01～0.05%, B 0.001～0.004%, S≤0.01%, P≤0.02%, surplus are Fe; And satisfy following the relation: 0.16%≤2Mo+W≤0.40%, 0.03%≤V+Ti≤0.08%, 0.03%≤Mg+Ca≤0.10%.
Chemical composition design is according to as follows:
Carbon: solid solution has the effect of obvious reinforcement matrix in ferrite, the intensity of steel is increased substantially, can improve room temperature and high-temperature yield strength especially, but carbon content is too high, then toughness reduces and the welding property deterioration, therefore carbon content is controlled at 0.04%～0.20%.
Manganese: manganese is the main alloy element in the metallurgical furnace shell material, and manganese enlarges the austenitic area of steel, reduces transformation temperature, obviously improves the hardening capacity of steel.In thermal deformation process, manganese also postpones the carrying out of soft steel working hardening phase transformation, and manganese content improves, finish the corresponding raising of the required overall strain of phase transformation, working hardening ferritic transformation time lengthening, strain improves, by the working hardening phase transformation, be easy to obtain the fine axle ferrite that waits.In addition, manganese can also improve the hot workability of steel.But the manganese too high levels can increase the production cost of steel, so manganese content is controlled at 0.60%～2.00%.
Silicon: silicon has deoxidation and strengthens the effect of matrix, improves the intensity of steel, and the silicon solid solution easily impels the matrix embrittlement in matrix, therefore silicone content is controlled at below 0.8%.
Tungsten and molybdenum: tungsten and molybdenum solid solution can obviously improve the high-temperature behavior of steel in steel, particularly can obviously improve the high temperature creep-resisting performance of steel, but add-on is too much, the plasticity and the toughness of steel will obviously be reduced, also reduce welding property, also increase the production cost of steel, therefore W content is controlled at 0.01～0.20%, molybdenum content is controlled at 0.01～0.10%, and 0.16%≤2Mo+W≤0.40%.
Vanadium, titanium, zirconium, aluminium, nitrogen, niobium: add an amount of vanadium, titanium, niobium and zirconium in the steel, can form compound with carbon, nitrogen, aluminium can form compound with oxygen, the effect of grain growth when the formed compound of these elements has obvious prevention heat improves the intensity of steel and improves the toughness of steel.In addition, niobium has the deformation inductdion of raising transformation temperature, and the effect of the distorted area of enlargement deformation induced transformation adds the easier acquisition ultra-fine grained ferrite of an amount of niobium in the steel, improve the obdurability of steel.But when add-on is too much, it is thick to form too much compound and compound in the steel, obviously reduce the toughness of steel, therefore, suitable content of vanadium is 0.01～0.05%, suitable titanium content is 0.01～0.05%, and 0.03%≤V+Ti≤0.08%, suitable zirconium content is 0.01～0.05%, suitable aluminium content is 0.01%～0.07%, suitable nitrogen content is 0.02%～0.08%, and suitable content of niobium is 0.01%～0.05%.
Cerium: cerium adds the effect that has desulfurization, degasification in the steel, the fine particle of cerium and liquid reactant metal generation simultaneously, the forming core effect with accelerated solidification, the crystal grain of these characteristics energy refinement steel of Ce elements, the segregation of restriction dentrite alleviates element segregation in the steel, improves the comprehensive mechanical performance of steel.The cerium add-on is too much, and steel inclusion is increased, and reduces the intensity and the toughness of steel, and suitable cerium add-on is 0.03%～0.10%.
Boron: trace B can make the hardening capacity of steel significantly improve.Major cause is that austenite boron atom in the quench cooled process gathers partially on crystal boundary, reduce crystal boundary energy, suppressed ferritic forming core, postpone ferritic formation, the diffusion that boron atom on the while crystal boundary also blocks the crystal boundary atom, it is slow that ferrite divergent contour on crystal boundary is examined and made cuts, thereby increase hardening capacity.Boron is eliminated the effect of the temper brittleness of steel in addition, add boron in this and the steel after, generate BN, make the N atom not avoid relevant being diffused into about 300 ℃ near the dislocation to the pinning effect of dislocation.But boron solubleness in steel is very low, and add-on is too much, will cause the toughness of steel to reduce, and therefore its add-on is controlled at 0.001%～0.004%.
Magnesium and calcium: magnesium and sulphur, oxygen have great avidity, and violent metallurgical reaction can take place, and remove oxygen and sulphur in the steel, reduce oxide compound and sulfide inclusion in the steel.When the part MgO in deoxidation, the desulfurization product and MgS have little time to float when getting rid of to the molten steel surface, just become in the steel after solidifying to be mingled with.During solidification of molten steel, at first form MgO, it can be used as MgS, MnS and other core that is mingled with after coagulation.Because MgO disperses in molten steel especially, so magnesium can change type, quantity, size, form and the distribution of steel inclusion.An amount of magnesium can make steel inclusion become tiny, disperse.Original size is big, the MnS of strip is mingled with by little, the subglobose MgO of size, contains the MgO duplex impurity and the MgS.MgO duplex impurity replaces, thereby has improved inclusion and form and the ability of expanding with matrix opposing crackle, improves the toughness of steel.The magnesium add-on too much not only causes the waste of magnesium, and because reaction is too violent, MgO, the MgS etc. that float to the molten steel surface on making is mingled be involved in again in the molten steel, and the performance of steel is had a negative impact.Calcium and oxygen have very big avidity, and the deoxidizing capacity of calcium is very strong, and calcium has good degassing effect to molten steel.Calcium also has remarkable effect to steel inclusion rotten, add an amount of calcium and can change the strip sulfide inclusion in the steel into globular CaS or (Ca, Mn) S is mingled with, an amount of calcium also significantly reduces sulphur poly-partially at crystal boundary, and hot-cracking resistance is very useful to calcium to the fragility that reduces steel with when improving steel plate and casting.Add too much calcium steel inclusion will be increased, unfavorable to the toughness raising of steel, the present invention is controlled at 0～0.08% with Mg content, and calcium contents is controlled at 0～0.08%, and 0.03%≤Mg+Ca≤0.10%.
Inevitably trace impurity is to bring in the raw material, and p and s is wherein arranged, and all is harmful elements, and intensity, toughness and high-temperature behavior in order to guarantee the metallurgical furnace shell material are controlled at phosphorus content below 0.02%, and sulphur content is controlled at below 0.01%.
The manufacture method of high temperature creep-resisting furnace shell material of the present invention, its processing step comprise smelting, casting, rolling and normalizing treatment.
(1) smelts
Smelting comprises steel melting furnace smelting and external refining:
1. steel melting furnace is smelted and is carried out in electric furnace, when electrosmelting, earlier ordinary scrap steel, molybdenum-iron, ferrotungsten and ferro-niobium is added heat fused in the stove, and the molten clear back of molten steel adds ferrosilicon and manganeseiromization and pre-deoxidation; After the pre-deoxidation, skim at once and adjust composition, after composition is qualified temperature is risen to 1620～1680 ℃, add the aluminium deoxidation and the microalloying that account for molten steel weight 0.08%～0.30%, and add ferrotianium, vanadium iron, manganese nitride and ferro-boron, and tapping then, tapping temperature is 1630～1690 ℃.
Before the tapping, magnesium, calcium, zirconium and cerium are positioned over ladle bottom, with the method that pours in the bag molten steel are carried out composite inoculating and handle.Adopt electrosmelting, control composition easily, easy and simple to handle.
2. external refining is carried out in the LF stove, guarantees argon blowing time, and argon blowing time is greater than 15min; Argon can obviously reduce gas and inclusion content in the molten steel.
(2) casting
Cast on the slab caster and carry out, continuous casting becomes slab, and the pouring molten steel temperature is 1510～1550 ℃, pouring speed 1.0～1.8m/min; Adopt continuous cast method cast steel billet, the efficient height can reduce the steel rolling passage, raises the efficiency and cuts down the consumption of energy.
(3) rolling
Continuous casting steel billet is placed process furnace, continuous casting steel billet is heated to 1000～1180 ℃, and be incubated 1～5 hour, carry out hot rolling then, it is the steel plate of 20～120mm that slab rolling is become thickness.
(4) normalizing treatment
Above-mentioned steel plate is put into process furnace, steel plate is heated to 820～1020 ℃, be incubated 2～10 hours, air cooling subsequently, normalizing treatment is machined to specified dimension with steel plate then on finishing machine.
Carry out normalizing treatment and can realize austenitizing, make composition and homogeneous microstructureization, can prevent steel plate deformed, and make tissue and performance even, obtain to satisfy the steel plate materials of furnace shell service requirements.
Adopt manufacture method of the present invention, the metallurgical furnace shell material excellent comprehensive mechanical property of production.Its tensile strength reaches 530～560MPa, yield strength reaches 370～430MPa, unit elongation reaches 30%～36%, 0 ℃ of vertical summer is 188～274J than V-type ballistic work, the Z of anti-lamellar tearing performance requriements is punctured into 30%～63% to section, in the time of 650 ℃, the lasting rupture time under 200MPa stress was greater than 15 hours.180 ° of horizontal clod washes of steel plate (d=3a, B=35mm) intact, defectives such as crackle do not appear.And having excellent high, 350 ℃ of high-temperature yield strengths reach 270～310MPa.
Compared with prior art, the present invention has following advantage:
1. the present invention be on C-Mn alloy system basis, added Ce, Nb, N, Al, Zr, B and V and (or) Ti and Ca and (or) microalloy element such as Mg, reach multielement enhanced purpose, the metallographic structure of gained steel is based on tiny ferrite, contain 5%～15% retained austenite, make material have the excellent comprehensive mechanical property.
2. the metallurgical furnace shell material of manufacturing of the present invention contains raising hot strength element W, Mo etc., and high-temperature behavior is obviously improved.
Advantages such as 3. the metallurgical furnace shell material produced of the present invention is used for mammoth conveter, has good welding performance, and the high temperature creep-resisting performance is good can obviously reduce shell deformation, prolong furnace shell work-ing life, have good economic benefits.
4. manufacture method of the present invention all adopts conventional Iron and Steel Production equipment, and technology is simple, so production cost is low, produces easy to maintenance.
The invention will be further described below in conjunction with embodiment:
Embodiment:
Embodiment
According to manufacture method of the present invention, on 45 tons of direct current electric arc furnaces, smelt 3 stoves high temperature creep-resisting furnace shell furnace shell material of the present invention, the chemical ingredients of 3 stove steel is as shown in table 1.Furnace charge is added Hybrid Heating fusing in the stove, and the molten clear back of molten steel adds ferrosilicon and manganeseiromization and pre-deoxidation; The stokehold is adjusted to branch and temperature is risen to relevant temperature after qualified, and adds the aluminium of respective amount, carries out deoxidation and microalloying, and adds vanadium iron, ferrotianium, manganese nitride and ferro-boron, then comes out of the stove; Temperature before the add-on of the qualified back of composition reductor aluminium and aluminium add is listed in the table 2.
Calcium, magnesium, zirconium and cerium are positioned over ladle bottom, with the method that pours in the bag molten steel are carried out composite inoculating and handle; Molten steel is added in the LF stove then, carry out external refining, argon blowing time is also listed in the table 2.
Pour into slab after molten steel is come out of the stove on slab caster, pouring molten steel temperature and pouring speed are as shown in table 2.
Continuous casting steel billet is reheated, and behind the insulation certain hour, on the 4200mm milling train, be rolled, the 4200mm milling train is furnished with laser thickness gauge and AGC automatic gauge control system, accurately control thickness tolerance and plate shape, thickness deviation can be controlled at-0.3～+ 0.5mm, the roughness of steel plate can be controlled in below the 3mm/m.Roll the speed of cooling of back, prevent that recrystal grain from growing up by ACC system control steel plate.Thickness after the hot-rolled steel plate processing is 60mm～70mm.Slab heating temperature, soaking time and start rolling temperature are listed in the table 2.
With final rolling hot-rolled steel sheet sampling, and be heated to air cooling after differing temps and the different soaking time in batches, carry out normalizing treatment, on finishing machine, be machined to specified dimension then.The temperature and the soaking time of normalizing treatment are as shown in table 3.
To the steel plate sampling through normalizing treatment, carry out mechanical property test at last, test-results is listed in the table 4.
The finished product steel plate of embodiment heat (batch) number 1 is carried out commerical test as the large converter shell material, and the result is as follows:
Because furnace shell material composition of the present invention and tissue distribution are even, the inclusion amount is few in the tissue, organizes tinyly, fine and close, and mechanical property is good.Also have good formability and welding property in addition, the postwelding unrelieved stress is little.Use the test result after a year to show, in identical working conditions, the deflection of the converter shell of material preparation of the present invention reduces 25%～32% than traditional burner shell material, illustrate that furnace shell material of the present invention has good high temperature creep-resisting ability, be used for large converter shell, can obviously prolong converter shell work-ing life, have good economic benefits.
The chemical ingredients (weight %) of table 1 embodiment steel grade
| Heat (batch) number | C | Mn | Si | Mo | W | V | Ti | Nb | N |
| 1 | 0.11 | 1.18 | 0.21 | 0.09 | 0.05 | 0.04 | 0.02 | 0.04 | 0.04 |
| 2 | 0.08 | 1.35 | 0.39 | 0.05 | 0.17 | 0.02 | 0.04 | 0.03 | 0.05 |
| 3 | 0.10 | 1.27 | 0.31 | 0.07 | 0.10 | 0.03 | 0.02 | 0.03 | 0.04 |
Continuous table 1
| Heat (batch) number | Ce | Al | Mg | Ca | Zr | B | P | S | Fe |
| 1 | 0.05 | 0.04 | - | 0.07 | 0.02 | 0.002 | 0.006 | 0.013 | Surplus |
| 2 | 0.07 | 0.02 | 0.03 | 0.06 | 0.03 | 0.003 | 0.008 | 0.017 | Surplus |
| 3 | 0.06 | 0.03 | 0.04 | 0.05 | 0.02 | 0.03 | 0.007 | 0.015 | Surplus |
Table 2 embodiment smelting, casting and hot rolling have related parameter
| Heat (batch) number | Add liquid steel temperature before the aluminium/℃ | Add aluminium amount wt% | Argon blowing time min | Pouring molten steel | The hot rolling slab heating | Hot rolling start rolling temperature ℃ | ||
| Temperature ℃ | Speed m/min | Temperature ℃ | Time h | |||||
| 1 | 1670 | 0.20 | 19 | 1520 | 1.7 | 1130 | 3.0 | 1105 |
| 2 | 1660 | 0.15 | 17 | 1535 | 1.2 | 1150 | 2.2 | 1117 |
| 3 | 1650 | 0.18 | 18 | 1530 | 1.5 | 1140 | 2.5 | 1110 |
The normalizing treatment parameter of table 3 embodiment steel plate sample
The Mechanics Performance Testing result of table 4 embodiment steel plate sample
| Heat (batch) number | Lot number | Specification mm | σ s MPa | σ b MPa | δ ％ | A KV, 0 ℃ of J, vertically | Zz ％ | 350℃ σ s/MPa | High temperature creep-resisting performance/h |
| 1 | 27 | 70 | 370 | 550 | 34 | 274 | 32 | 310 | 15.3 |
| 28 | 70 | 420 | 550 | 32 | 262 | 30 | 285 | 15.6 | |
| 29 | 70 | 385 | 530 | 36 | 240 | 35 | 290 | 15.5 | |
| 30 | 70 | 430 | 560 | 30 | 250 | 54 | 275 | 15.1 | |
| 2 | 05 | 60 | 385 | 535 | 34 | 256 | 63 | 270 | 15.2 |
| 06 | 60 | 410 | 540 | 36 | 188 | 61 | 280 | 15.8 | |
| 07 | 60 | 430 | 560 | 30 | 250 | 54 | 275 | 15.4 | |
| 08 | 60 | 392 | 530 | 35 | 244 | 59 | 285 | 15.5 | |
| 3 | 11 | 70 | 424 | 548 | 35 | 248 | 54 | 282 | 15.1 |
Annotate: the high temperature creep-resisting performance is during with 650 ℃, and the lasting rupture time under 200MPa stress is evaluated.
Claims (2)
1. high temperature creep-resisting furnace shell material, it is characterized in that its chemical ingredients (weight %) is: C 0.04～0.20%, and Mn 0.60～2.00%, Si≤0.8%, W 0.01～0.20%, and Mo 0.01～0.10%, V 0.01～0.05%, Ti 0.01～0.05%, and Nb 0.01～0.05%, and N 0.02～0.08%, Ce0.03～0.10%, Al 0.01～0.07%, and Mg 0～0.08%, and Ca 0～0.08%, Zr 0.01～0.05%, B0.001～0.004%, S≤0.01%, P≤0.02%, surplus is Fe, and satisfy following the relation: 0.1 6%≤2Mo+W≤0.40%, 0.03%≤V+Ti≤0.08%, 0.03%≤Mg+Ca≤0.10%.
2. the manufacture method of the described high temperature creep-resisting furnace shell material of claim 1 is characterized in that its processing step comprises smelting, casting, rolling, normalizing treatment:
(1) smelts
Smelting comprises steel melting furnace smelting and external refining:
1. steel melting furnace is smelted and is carried out in electric furnace, when smelting in electric furnace, earlier ordinary scrap steel, molybdenum-iron, ferrotungsten and ferro-niobium is added heat fused in the stove, and the molten clear back of molten steel adds ferrosilicon and manganeseiromization and pre-deoxidation; After the pre-deoxidation, skim at once and adjust composition, after composition is qualified temperature is risen to 1620～1680 ℃, add the aluminium deoxidation and the microalloying that account for molten steel weight 0.08%～0.30%, and add ferrotianium, vanadium iron, manganese nitride and ferro-boron, and tapping then, tapping temperature is 1630～1690 ℃; Before coming out of the stove, magnesium, calcium, zirconium and cerium are positioned over ladle bottom, with the method that pours in the bag molten steel are carried out composite inoculating and handle;
2. external refining is carried out in the LF stove, and argon blowing time is greater than 15min;
(2) casting
Cast on the slab caster and carry out, continuous casting becomes slab, and the pouring molten steel temperature is 1510～1550 ℃, pouring speed 1.0～1.8m/min;
(3) rolling
Continuous casting steel billet is placed process furnace, be heated to 1000～1180 ℃, and be incubated 1～5 hour, carry out hot rolling then, it is the steel plate of 20～120mm that slab rolling is become thickness;
(4) normalizing treatment
Above-mentioned steel plate is put into process furnace, steel plate is heated to 820～1020 ℃, be incubated 2～10 hours, air cooling is machined to specified dimension with steel plate then on finishing machine subsequently.
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| CN102517495A (en) * | 2011-12-02 | 2012-06-27 | 内蒙古科技大学 | Method for refining pipeline steel casting blank tissue crystal grains |
| TWI490339B (en) * | 2013-05-27 | 2015-07-01 | 中國鋼鐵股份有限公司 | Method of making steel |
| CN107138919B (en) * | 2017-05-18 | 2023-04-14 | 西安建筑科技大学 | Manufacturing process of C-shaped opening cylindrical shell with threshold buckling unloading self-resetting function |
| CN108893681B (en) * | 2018-06-26 | 2020-08-25 | 武汉钢铁有限公司 | High-strength high-toughness pressure vessel steel plate and preparation method thereof |
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| JP2002146470A (en) * | 2000-11-13 | 2002-05-22 | Nippon Steel Corp | Low quenching or normalizing type low alloy steel sheet for boiler steel tube having excellent toughness and method for producing steel tube using the steel sheet |
| CN1414130A (en) * | 2002-09-27 | 2003-04-30 | 玛努尔(烟台)工业有限公司 | Fe-Cr-Ni cast alloy haring both creep deformation and toughness and its manufacturing method |
| JP2003253331A (en) * | 2002-03-05 | 2003-09-10 | Nippon Steel Corp | Method for manufacturing high-tensile-strength steel with high toughness and high ductility |
| JP2003342670A (en) * | 2002-05-24 | 2003-12-03 | Nippon Steel Corp | Non-heat treated high tensile steel having excellent toughness |
| JP2005021981A (en) * | 2003-02-26 | 2005-01-27 | Nippon Steel Corp | Welded joint excellent in corrosion resistance |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| JP2002146470A (en) * | 2000-11-13 | 2002-05-22 | Nippon Steel Corp | Low quenching or normalizing type low alloy steel sheet for boiler steel tube having excellent toughness and method for producing steel tube using the steel sheet |
| JP2003253331A (en) * | 2002-03-05 | 2003-09-10 | Nippon Steel Corp | Method for manufacturing high-tensile-strength steel with high toughness and high ductility |
| JP2003342670A (en) * | 2002-05-24 | 2003-12-03 | Nippon Steel Corp | Non-heat treated high tensile steel having excellent toughness |
| CN1414130A (en) * | 2002-09-27 | 2003-04-30 | 玛努尔(烟台)工业有限公司 | Fe-Cr-Ni cast alloy haring both creep deformation and toughness and its manufacturing method |
| JP2005021981A (en) * | 2003-02-26 | 2005-01-27 | Nippon Steel Corp | Welded joint excellent in corrosion resistance |
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