CN102453831A - Method for smelting high-chromium steel and high-chromium steel - Google Patents
Method for smelting high-chromium steel and high-chromium steel Download PDFInfo
- Publication number
- CN102453831A CN102453831A CN2010105233936A CN201010523393A CN102453831A CN 102453831 A CN102453831 A CN 102453831A CN 2010105233936 A CN2010105233936 A CN 2010105233936A CN 201010523393 A CN201010523393 A CN 201010523393A CN 102453831 A CN102453831 A CN 102453831A
- Authority
- CN
- China
- Prior art keywords
- steel
- molten steel
- add
- refining
- ladle
- 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.)
- Granted
Links
Landscapes
- Treatment Of Steel In Its Molten State (AREA)
Abstract
The invention provides a method for smelting high-chromium steel, which comprises the steps of: primarily smelting molten iron in a rotating furnace; tapping molten steel after the primary smelting into a steel ladle, adding high carbon ferrochrome in the tapping progress, thus enabling Cr content in the molten steel to reach 1.8-2.4 wt%; refining the steel ladle by an LF furnace, adding low carbon ferrochrome in the steel ladle refining progress by the LF furnace, wherein, on the basis of addition amount of chromium, a weight ratio of the low carbon ferrochrome to the high carbon ferrochrome is (1: 2) to (1: 3.5); and carrying out RH vacuum refining upon molten steel after steel ladle refining by the LF furnace. The invention further provides high-chromium steel smelted by the method for smelting the high-chromium steel disclosed by the invention. Through the technical proposal, the method disclosed by the invention fully considers the influence to temperature and carbon composition of the molten steel due to addition of chromium alloy, and is good for matching of production rhythm among working procedures, so that production can be carried out smoothly. In addition, through the method disclosed by the invention, yield of the chromium is high, and high-chromium steel with a higher Cr content is obtained in an economical manner.
Description
Technical field
The present invention relates to smelt the method and the high chromium steel of high chromium steel.
Background technology
High chromium steel be used to make bear load, complex-shaped, require the grinding tool material that distortion is little, wear resistance is high, red hardness is good.High chromium steel is normally realized through adding ferrochrome in smelting process.
But because the Cr content of common molten iron own is extremely low, for example the half steel after the vanadium extraction can only improve Cr content through the deoxidation alloying behind the converter tapping, just in tapping process, adds ferrochrome.But the rapid increase of the Cr content in this process molten steel can cause liquid steel temperature sharply to descend, and influences subsequent disposal, has for example prolonged the heat-up time when LF stove ladle refining.In addition, for the lower steel grade of finished product carbon content, if adopt high carbon ferro-chrome can influence C content; Thereby can't obtain the molten steel of required composition; Therefore in order to improve Cr content, need in tapping process, add the higher low carbon ferrochromium of Cr content usually, so that the yield of chromium is higher.But the price of low carbon ferrochromium is comparatively expensive, has increased production cost.
Summary of the invention
Technical problem to be solved by this invention is to smelt high chromium steel through the half steel after the simple process steps use vanadium extraction.
For solving the problems of the technologies described above, the present invention provides a kind of method of smelting high chromium steel, and this method comprises: in converter, molten iron is carried out refining just; Molten steel after the refining is just tapped in the ladle, in tapping process, add high carbon ferro-chrome, make that the Cr content in the molten steel reaches 1.8～2.4 weight %; Ladle is carried out LF stove ladle refining, in LF stove ladle refining process, add low carbon ferrochromium, the weight ratio in the add-on of chromium content of said low carbon ferrochromium and said high carbon ferro-chrome is 1: 2～1: 3.5; Molten steel to behind the LF stove ladle refining carries out the RH vacuum refinement.
The present invention also provides a kind of high chromium steel of being smelted by the method for smelting high chromium steel of the present invention.The mass percent of the composition of said high chromium steel is C:0.15～0.20%, Si:0.15～0.30%, Mn:0.45～0.60%; S:0.002～0.008%; P:0.004～0.008%, Cr:2.8～3.2%, Mo:0.40～0.50%; Full aluminium: 0.01～0.04%, Fe:95.2～95.98%
The present invention has taken into full account and has added the influence of Chrome metal powder to liquid steel temperature and carbon component, comes progressively to improve the Cr content in the molten steel through add Chrome metal powder in batches, avoids making liquid steel temperature to descend too much simultaneously.Thereby help from converter to the LF stove and linking, make rhythm of production be complementary, thereby guaranteed carrying out smoothly of production from the LF stove to the molten steel state the RH stove.In addition, through method of the present invention, with respect to comparatively expensive low carbon ferrochromium, comparatively the add-on of cheap high carbon ferro-chrome is bigger, thereby can obtain the higher high chromium steel of Cr content economically.
Other features and advantages of the present invention will partly specify in embodiment subsequently.
Embodiment
Following specific embodiments of the invention is elaborated.Should be understood that embodiment described herein only is used for explanation and explains the present invention, is not limited to the present invention.
The method of smelting high chromium steel of the present invention comprises: use converter to carry out refining just; In converter, molten steel is carried out refining just; In converter, molten iron is carried out refining just; Molten steel after the refining is just tapped in the ladle, in tapping process, add high carbon ferro-chrome, make that the Cr content in the molten steel reaches 1.8～2.4 weight %; Ladle is carried out LF stove ladle refining, in LF stove ladle refining process, add low carbon ferrochromium, the weight ratio in the add-on of chromium content of said low carbon ferrochromium and said high carbon ferro-chrome is 1: 2～1: 3.5; Molten steel to behind the LF stove ladle refining carries out the RH vacuum refinement.Wherein, " in the add-on of chromium " expression joins the add-on of the chromium in the molten steel through adding high carbon ferro-chrome or low carbon ferrochromium.
Preferably, in the step that adds high carbon ferro-chrome, make that the Cr content in the molten steel reaches 2.0～2.2 weight %.
Wherein, according to the molten steel composition of final smelting, can add the high carbon ferro-chrome and the low carbon ferrochromium of the various suitable trades mark.In embodiments of the present invention, said high carbon ferro-chrome is FeCr
67C
6.0, FeCr
55C
600, FeCr
67C
9.5, FeCr
55C
1000In at least a; Said low carbon ferrochromium is FeCr
69C
0.25, FeCr
55C
25, FeCr
69C
0.50, FeCr
55C
50In at least a.
According to the Cr content in the first steel-making water,, can add the high carbon ferro-chrome and the low carbon ferrochromium of different amounts through method of the present invention.Preferably, the add-on of said high carbon ferro-chrome is 30～40kg/ ton molten steel, and the add-on of said low carbon ferrochromium is 10～15kg/ ton molten steel.
Wherein, high carbon ferro-chrome can add separately, also can when tapping, add in the molten steel to carry out deoxidation alloying with other alloy and carburelant.Preferably, added said high carbon ferro-chrome at 20～40% o'clock in tapping, thereby make alloying more abundant.In addition, low carbon ferrochromium adds when the alloying of LF stove ladle refining.
Preferably, method of the present invention is included in and adds low carbon ferrochromium when carrying out the RH vacuum refinement, and the add-on of this low carbon ferrochromium is smaller or equal to 3kg/ ton molten steel and greater than 0.Cr content can be further increased in this way, and the Cr content demand of different steel grades can be satisfied.More preferably, the add-on of this low carbon ferrochromium is 0.85～1kg/ ton molten steel.Through mending into suitable low carbon ferrochromium when the RH vacuum refinement, can further improve Cr content, to obtain the Cr content of final required molten steel.Wherein, mending the low carbon ferrochromium of going into adds when the alloying of RH vacuum refinement.
In the present invention, the molten iron that is used to carry out just refining can be various types of molten iron, obtains the higher molten steel of Cr content thereby smelt.This molten iron even can be the vanadium-titanium-iron-water that is not easy to improve Cr content.To carry out refining just through the half steel after the use vanadium extraction in converter in an embodiment of the present invention method of the present invention will be described.Wherein, the mass percent of the composition of said half steel is C:3.5～3.8%, V:0.025～0.036%, Mn:0.03～0.07%, Cr:0.04～0.06%, S:0.002～0.005%, P:0.04～0.07%, Fe:95.96～96.36%.Also can obtain the higher molten steel of Cr content through method of the present invention even one skilled in the art will appreciate that the vanadium extraction half steel that is not easy to improve Cr content, other molten iron or half steel that is used for refining just then is suitable for method of the present invention more easily.
After said half steel carried out converter refining just, the mass percent of composition of water of just making steel was: C:0.035～0.050%, Mn:0.01～0.04%; Cr:0.03～0.04%; P:0.004～0.006%, S:0.003～0.006%, Fe:Fe:99.86～99.91%.
Smelt the method for first steel-making water can adopt the method for making steel of various routines said half steel; For example can use the top-bottom blowing method for making steel of oxygen top blown converter steel making method or oxygen top blown+bottom blowing shielding gas, the present invention preferably adopts the top-bottom blowing method for making steel of oxygen top blown+bottom blowing shielding gas.Preferably, when carrying out refining just, can make that just the P content of steel-making water is 0.002～0.0035 weight % through using the double slag process dephosphorization.More preferably; In said double slag process; Add slag making materials for the first time in beginning oxygen blast for the first time in 6 minutes; This, slag making materials can comprise the quickened lime of 30～33kg/ ton half steel, the composite fluxing medium of 17～19kg/ ton half steel, the sludge ball of steel smelting of the high magnesium lime of 17～19kg/ ton half steel and 2.7～3.1kg/ ton half steel first time; Add slag making materials for the second time in beginning oxygen blast for the second time in 6 minutes, this, slag making materials can comprise the quickened lime of 17.5～20kg/ ton half steel, the composite fluxing medium of 5.7～7kg/ ton half steel, the high magnesium lime of 5.7～7kg/ ton half steel second time.
In the present invention, can add suitable refining slag and reductor according to needs to molten steel composition.Consider the influence of the increase of Cr content in the molten steel, can add refining slag and reductor several times LF stove ladle refining.Preferably, method of the present invention comprises: this method comprises: before adding said high carbon ferro-chrome, from tapping to 20～30% process, add the duraluminum reductor of 2.2～2.8kg/ ton molten steel; After adding said high carbon ferro-chrome, in tapping to 30～50% process, add the refining slag of 4.6～5.2kg/ ton molten steel; After tapping is accomplished and before LF stove ladle refining, add the refining slag of 1.13～1.2kg/ ton molten steel and the deoxidation aluminum shot of 0.15～0.22kg/ ton molten steel; In LF stove ladle refining heat-processed, add the refining slag of 0.7～1.02kg/ ton molten steel and the deoxidation aluminum shot of 0.08～0.4kg/ ton molten steel in ladle slag fusing back.
According to the final steel water constituent, can select the refining slag and the duraluminum reductor of various suitable types for use.In preferred implementation of the present invention, the mass percent of the composition of said refining slag is: CaO:70～80%, Al
2O
3: 2～8%, MgO:0～5%, SiO
2: 0～3%, Na
2O:3～5%, CaF
2: 8～14%; The mass percent of the composition of said duraluminum reductor is: Al:38～50%, Fe:50～62%; The mass percent of the composition of said deoxidation aluminum shot is Al:95～99%, Al
2O
3: 1～5%.
It should be understood that; According to the different production pattern; Can converter just be refined, LF stove ladle refining and RH vacuum refinement carry out continuously, thereby realize the linking between each step easily through the parameter of controlling in each step, and can be connected with follow-up for example continuous casting working procedure.In other words, can make the state of molten steel behind state and the LF stove ladle refining of first steel-making water be suitable for the processing of next step.Preferably, just making steel the temperature of water is 1690～1700 ℃; The treatment time of LF stove ladle refining is 40～45 minutes; In the RH vacuum refinement; The flow of driving gas is 1200～1400NL/ minute, vacuum tightness less than the situation of 3mbar under circular treatment time more than 12 minutes, for example 12～18 minutes; Under the situation that keeps this vacuum tightness, carry out alloying then, circular treatment is 5 minutes after the alloying.
Through specific embodiment method of the present invention is described below, the half steel that all is suitable among each embodiment after the vanadium extraction be difficult to improve Cr content is a raw material.
Embodiment 1
With the half steel after the vanadium extraction is that raw material carries out refining just, and the mass percent of the composition of this half steel is: C:3.65%, and V:0.036%, Mn:0.05%, Cr:0.042%, P:0.060%, S:0.003%, Fe:96.15%, surplus is an impurity.
This half steel is blended into multiple blowing steel converter blowing, and adopts 536 oxygen rifles to carry out the decarburization of oxygen supply slag making dephosphorization.At the oxygen blown steelmaking slagging first time that carries out simultaneously of beginning, and open blow in the oxygen supply 6 minutes will the first time slag making materials all add.For the first time in the slag making materials, the add-on of quickened lime, composite fluxing medium, high magnesium lime and sludge ball of steel smelting is respectively 30kg/t half steel, 19kg/t half steel, 19kg/t half steel and 2.8kg/t half steel for this; Oxygen supply time stops oxygen supply and promotes the oxygen rifle in the time of 450 seconds, and stove is got rid of slag.The mass percent of wherein said each composition of quickened lime is: CaO:96%, SiO
2: 0.391%, MgO:3.25%, surplus is an impurity; The mass percent of wherein said each composition of composite fluxing medium is: CaO:11.61%, SiO
2: 50%, MgO:12.74%, Al
2O
3: 2.75%, Fe
2O
3: 11.44%, FeO:5.79%, C:1.26%, S:0.106%, P:0.044%, surplus is an impurity; Each composition quality mark of wherein said high magnesium lime is: CaO:54.32%, SiO
2: 1.64%, MgO:38.59%, Fe
2O
3: 0.219%, FeO:0.2%, C:0.101%, surplus is an impurity; The mass percent of wherein said each composition of sludge ball of steel smelting is: CaO:29.29%, SiO
2: 7.5%, MgO:9.35%, Fe
2O
3: 9.87%, FeO:32.8%, C:4.24%, surplus is an impurity.Get rid of the slag total amount 60% after converter is returned zero-bit carry out oxygen supply and carry out slag making second time, and open for the second time blow in the oxygen supply 6 minutes will the second time slag making materials all add.This, slag making materials comprised quickened lime, composite fluxing medium and high magnesium lime second time; Add-on is respectively 19kg/t half steel, 6kg/t half steel and 6kg/t half steel; Oxygen supply time stops oxygen supply and promotes the oxygen rifle in the time of 650 seconds, the acquisition temperature is 1690 ℃ a molten steel.The mass percent of the staple of wherein said molten steel is: C:0.045%, and Mn:0.04%, Cr:0.04%, P:0.006%, S:0.006%, Fe:99.86%, surplus is an impurity.In stove, add the high magnesium lime of 3.5kg/t half steel then and blow stirring 2 minutes again, carry out pushing off the slag then and come out of the stove.From tapping to 20% the process that begins to tap, in ladle, add the ferro-aluminum reductor of 2.2kg/t steel, the mass percent of the composition of said duraluminum reductor is: Al:38%, and Fe:60%, all the other are trace impurity; The ferrosilicon, the ferromanganese of 8.0kg/t steel and the high carbon ferro-chrome of 36kg/t steel that in tapping to 20～30% process, add the 1.8kg/t steel carry out the molten steel alloying, and the carburelant of adding 0.4kg/t steel carries out carburetting.Wherein, high carbon ferro-chrome is that weight ratio is 1: 1 FeCr
67C
6.0And FeCr
55C
600The mass percent of said ferrosilicon composition is Si:74.5%, Al:18%, and Ca:0.5%, Mn:0.3%, Cr:0.2%, P:0.01%, S:0.01%, C:0.08%, surplus is Fe; The mass percent of said ferromanganese composition is: Mn:74.5%, and C:1.5%, Si:1.5%, P:0.01%, S:0.01%, surplus is Fe; The mass percent of said carburelant composition is: CaO:0.2%, SiO
2: 3.19%, MgO:0.2%, Fe
2O
3: 0.676%, FeO:0.901%, C:86.02%, S:0.21%, P:0.09%, surplus is an impurity.In the process of tapping 30～40%, add first refining slag of 4.6kg/t steel, the mass percent of the composition of refining slag is: CaO:72%, Al
2O
3: 7%, MgO:3%, SiO
2: 3%, Na
2O:3%, CaF
2: 12%.The interior liquid steel temperature of back ladle of having tapped is 1572 ℃; Again in ladle behind the Argon 5min temperature be 1542 ℃; Wherein Argon intensity is 3.3NL/ ton molten steel minute; Thereby obtain the molten steel of deoxidation alloying, the Cr content in the molten steel of this deoxidation alloying is 2.01%, and the yield of above-mentioned high carbon chromium siderochrome is 97.5%.
Molten steel behind the deoxidation alloying through LF stove ladle refining, is promptly carried out electrically heated and trimming and handles in the LF stove, the temperature that molten steel arrives the LF stove is 1539 ℃.Ladle adds second batch of refining slag and deoxidation aluminum shot during to the LF stove, and wherein, the add-on of the second batch of refining slag and deoxidation aluminum shot is respectively 1.13kg/t molten steel and 0.15kg/t molten steel, begins the electrically heated of LF stove then.After the second batch of refining slag fusion that adds, add the 3rd batch of refining slag and deoxidation aluminum shot, the add-on of refining slag and deoxidation aluminum shot is respectively 1.02kg/t molten steel and 0.11kg/t molten steel.The composition of second batch of refining slag, the 3rd batch of refining slag is identical with the composition of first refining slag, and the mass percent of the composition of deoxidation aluminum shot is: Al:95%, Al
2O
3: 4%, all the other are trace impurity.After treating the 3rd batch of refining slag fusion, in ladle, add low carbon ferrochromium by LF stove alloy feed bin, low carbon ferrochromium is that weight ratio is 1: 1 FeCr
69C
0.50And FeCr
55C
50, and the add-on of low carbon ferrochromium is the 13.5kg/t molten steel.The treatment time of LF stove ladle refining is 45 minutes, and the temperature that processing finishes is 1639 ℃, and the Cr content in the molten steel after the processing is 2.78%, and the yield of above-mentioned low carbon ferrochromium is 98.5%.
Ladle behind the LF stove ladle refining is carried out the RH vacuum refinement, and the temperature that molten steel reaches the RH stove is 1622 ℃.In the vacuum refinement process, the flow of driving gas is 1200NL/ minute, and handles 12 minutes under less than the situation of 3mbar in vacuum tightness; Keep vacuum tightness then, add alloy and carburelant and carry out alloying and carburetting, alloy comprises ferrosilicon, ferromanganese and low carbon ferrochromium.The composition of said ferrosilicon, said ferromanganese and said carburelant is identical with the composition of ferrosilicon, ferromanganese and carburelant that when tapping adds, and add-on is respectively 1.15kg/ ton molten steel, 1.16kg/ ton molten steel and 0.43kg ton molten steel; Low carbon ferrochromium is that weight ratio is 1: 1 FeCr
69C
0.50And FeCr
55C
50, and add-on is the 1.2kg/t molten steel.Circular treatment is 5 minutes after the alloying, so that composition evenly also finally obtains high chromium steel water, the mass percent of composition is C:0.15%; Si:0.25%, Mn:0.52%, S:0.005%; P:0.006%, Cr:2.85%, Mo:0.40%; Full aluminium: 0.04%, Fe:95.72%, surplus is an impurity.The yield of the vacuum treated low carbon ferrochromium of RH is 99.5%, and liquid steel temperature was 1578 ℃ when the RH processing finished.
Can ladle be carried out subsequent operations then, for example ladle is sent to continuous casting.
Embodiment 2
Use the method for embodiment 1 to smelt, wherein, being used for just, the mass percent of the composition of the half steel of refining is: C:3.8%, and V:0.025%, Mn:0.07%, Cr:0.04%, P:0.04%, S:0.002%, Fe:96.02%, surplus is an impurity.
This half steel is blended into multiple blowing steel converter blowing, and adopts 536 oxygen rifles to carry out the decarburization of oxygen supply slag making dephosphorization.In the slag making materials, the add-on of quickened lime, composite fluxing medium, high magnesium lime and sludge ball of steel smelting is respectively 33kg/t half steel, 18kg/t half steel, 17kg/t half steel and 2.7kg/t half steel for the first time; In the slag making materials, the add-on of quickened lime, composite fluxing medium and high magnesium lime is respectively 17.5kg/t half steel, 5.7kg/t half steel and 5.7kg/t half steel for the second time; Final acquisition temperature is 1693 ℃ a molten steel.Wherein, the mass percent of the staple of said molten steel is: C:0.05%, and Mn:0.025%, P:0.005%, Cr:0.03%, S:0.004%, Fe:99.88%, surplus is an impurity.In stove, add the high magnesium lime of 3.7kg/t half steel then and blow stirring 3 minutes again, carry out pushing off the slag then and come out of the stove.From tapping to 25% the process that begins to tap, in ladle, add the ferro-aluminum reductor of 2.3kg/t steel, the mass percent of the composition of said duraluminum reductor is: Al:48%, and Fe:50%, all the other are trace impurity; The ferrosilicon, the ferromanganese of 8.3kg/t steel, the high carbon ferro-chrome of 30kg/t steel and the carburelant steel of 0.45kg/t that in the process of tapping 25～35%, add the 1.85kg/t steel carry out molten steel alloying and carburetting.Wherein, high carbon ferro-chrome is that weight ratio is 1: 1 FeCr
67C
6.0And FeCr
55C
600In the process of tapping 35～45%, add the refining slag of first 4.8kg/t steel, the mass percent of the composition of refining slag is: CaO:75%, Al
2O
3: 5%, MgO:3%, SiO
2: 3%, Na
2O:4%, CaF
2: 10%.The interior liquid steel temperature of back ladle of having tapped is 1575 ℃; Again in ladle behind the Argon 5min temperature be 1544 ℃; Wherein Argon intensity is 3.4NL/ ton molten steel minute; Thereby obtain the molten steel of deoxidation alloying, the Cr content in the molten steel of this deoxidation alloying is 2.12%, and the yield of above-mentioned high carbon ferro-chrome is 97.7%.
Through LF stove ladle refining, the temperature that molten steel arrives the LF stove is 1538 ℃ with the molten steel behind the deoxidation alloying, promptly in the LF stove, carries out electrically heated and trimming and handles.Ladle adds second batch of refining slag and deoxidation aluminum shot during to the LF stove, and wherein, the add-on of the second batch of refining slag and deoxidation aluminum shot is respectively 1.15kg/t molten steel and 0.18kg/t molten steel, begins the electrically heated of LF stove then.After the second batch of refining slag fusion that adds, add the 3rd batch of refining slag and deoxidation aluminum shot, the add-on of refining slag and deoxidation aluminum shot is respectively 0.95kg/t molten steel and 0.08kg/t molten steel.The mass percent of the composition of deoxidation aluminum shot is: Al:96%, Al
2O
3: 3%, all the other are trace impurity.After treating the 3rd batch of refining slag fusion, in ladle, add low carbon ferrochromium by LF stove alloy feed bin, low carbon ferrochromium is that weight ratio is 1: 1 FeCr
69C
0.25And FeCr
55C
25, and the add-on of low carbon ferrochromium is the 15kg/t molten steel.The treatment time of LF stove ladle refining is 40 minutes, and the temperature that processing finishes is 1642 ℃, and the Cr content in the molten steel after the processing is 2.99%, and the yield of the low carbon ferrochromium of LF stove ladle refining is 98.4%.
Ladle behind the LF stove ladle refining is carried out the RH vacuum refinement, and the temperature that molten steel reaches the RH stove is 1625 ℃.In the vacuum refinement process, the flow of driving gas is 1300NL/ minute, and handles 18 minutes under less than the situation of 3mbar in vacuum tightness; Keep vacuum tightness then, and require adding alloy and carburelant to carry out alloying and carburetting according to steel grades.Alloy comprises ferrosilicon and ferromanganese.The composition of said ferrosilicon, said ferromanganese and said carburelant is identical with the composition of ferrosilicon, ferromanganese and carburelant that when tapping adds, and add-on is respectively 1.77kg/ ton molten steel, 0.69kg/ ton molten steel and 0.12kg/ ton molten steel; Circular treatment is 5 minutes after the alloying, so that composition evenly also finally obtains high chromium steel water, the mass percent of composition is C:0.18%; Si:0.15%, Mn:0.60%, S:0.002%; P:0.004%, Cr:2.99%, Mo:0.47%; Full aluminium: 0.02%, Fe:95.57%, surplus is an impurity.Liquid steel temperature was 1582 ℃ when the RH processing finished.
Can ladle be carried out subsequent operations then, for example ladle is sent to continuous casting.
Embodiment 3
Use the method for embodiment 1 to smelt, wherein, being used for just, the mass percent of the composition of the half steel of refining is: C:3.50%, and V:0.031%, Mn:0.03%, Cr:0.06%, P:0.07%, S:0.005%, Fe:96.3%, surplus is an impurity.
This half steel is blended into multiple blowing steel converter blowing, and adopts 536 oxygen rifles to carry out the decarburization of oxygen supply slag making dephosphorization.In the slag making materials, the add-on of quickened lime, composite fluxing medium, high magnesium lime and sludge ball of steel smelting is respectively 32kg/t half steel, 17kg/t half steel, 18kg/t half steel and 3.1kg/t half steel for the first time; In the slag making materials, the add-on of quickened lime, composite fluxing medium and high magnesium lime is respectively 20kg/t half steel, 7kg/t half steel and 7kg/t half steel for the second time; Final acquisition temperature is 1697 ℃ a molten steel.Wherein, the mass percent of the staple of said molten steel is: C:0.035%, and Mn:0.01%, Cr:0.035%, P:0.004%, S:0.003%, Fe:99.91%, surplus is an impurity.In stove, add the high magnesium lime of 3.6kg/t half steel then and blow stirring 3 minutes again, carry out pushing off the slag then and come out of the stove.From tapping to 30% the process that begins to tap, in ladle, add the ferro-aluminum reductor of 2.8kg/t steel, the mass percent of the composition of said duraluminum reductor is: Al:45%, and Fe:52%, all the other are trace impurity; The ferrosilicon, the ferromanganese of 8.2kg/t steel, the high carbon ferro-chrome of 40kg/t steel and the carburelant of 0.42kg/t steel that in the process of tapping 30～40%, add the 1.75kg/t steel carry out molten steel alloying and carburetting.Wherein, high carbon ferro-chrome is that weight ratio is 1: 1 FeCr
67C
6.0And FeCr
55C
600In the process of tapping 40～50%, add first refining slag of 5.2kg/t steel, the mass percent of the composition of first refining slag is: CaO:79%, Al
2O
3: 3%, MgO:2%, SiO
2: 2%, Na
2O:5%, CaF
2: 9%.The interior liquid steel temperature of back ladle of having tapped is 1583 ℃; Again in ladle behind the Argon 5min temperature be 1552 ℃; Wherein Argon intensity is 3.5NL/ ton molten steel minute; Thereby obtain the molten steel of deoxidation alloying, the Cr content in the molten steel of this deoxidation alloying is 2.17%, and the yield of above-mentioned high carbon ferro-chrome is 97.4%.
Molten steel behind the deoxidation alloying through LF stove ladle refining, is promptly carried out electrically heated and trimming and handles in the LF stove, the temperature that molten steel arrives the LF stove is 1545 ℃.Ladle adds second batch of refining slag and deoxidation aluminum shot during to the LF stove, and wherein, the add-on of the second batch of refining slag and deoxidation aluminum shot is respectively 1.2kg/t molten steel and 0.22kg/t molten steel, begins the electrically heated of LF stove then.After the second batch of refining slag fusion that adds, add the 3rd batch of refining slag and deoxidation aluminum shot, the add-on of refining slag and deoxidation aluminum shot is respectively 0.7kg/t molten steel and 0.4kg/t molten steel.The mass percent of the composition of deoxidation aluminum shot is: Al:99%, Al
2O
3: 1%.After treating the 3rd batch of refining slag fusion, in ladle, add low carbon ferrochromium by LF stove alloy feed bin, the add-on of low carbon ferrochromium is the 10kg/t molten steel.The treatment time of LF stove ladle refining is 42 minutes, and the temperature that processing finishes is 1647 ℃, and the Cr content in the molten steel after the processing is 2.93%, and the yield of the low carbon ferrochromium of LF stove ladle refining is 98.8%.
Ladle behind the LF stove ladle refining is carried out the RH vacuum refinement, and the temperature that molten steel reaches the RH stove is 1625 ℃.In the vacuum refinement process, the flow of driving gas is 1400NL/ minute, and handles 12 minutes under less than the situation of 3mbar in vacuum tightness; Keep vacuum tightness then, and require adding alloy and carburelant to carry out alloying and carburetting according to steel grades.Alloy comprises ferrosilicon, ferromanganese and low carbon ferrochromium.The composition of said ferrosilicon, said ferromanganese and said carburelant is identical with the composition of ferrosilicon, ferromanganese and carburelant that when tapping adds, and add-on is respectively 1.74kg/ ton molten steel, 0.6kg/ ton molten steel and 0.1kg/ ton molten steel; The add-on of low carbon ferrochromium is a 3.0kg/ ton steel.Circular treatment is 5 minutes after the alloying, so that composition evenly also finally obtains high chromium steel water, the mass percent of composition is C:0.20%; Si:0.15%, Mn:0.45%, S:0.008%; P:0.008%, Cr:3.11%, Mo:0.50%; Full aluminium: 0.01%, Fe:95.53%, surplus is an impurity.The yield of the vacuum treated low carbon ferrochromium of RH is 99.8%, and liquid steel temperature was 1585 ℃ when the RH processing finished.
Can ladle be carried out subsequent operations then, for example ladle is sent to continuous casting.
Comparative Examples 1
Use the method for embodiment 1 to smelt.
This half steel is blended into the blowing of multiple blowing steel converter, finally obtains temperature and be 1698 ℃ molten steel.The mass percent of the staple of wherein said molten steel is: C:0.042%, and Mn:0.035%, Cr:0.036%, P:0.0026%, S:0.028%, Fe:99.85%, surplus is an impurity.In stove, add the high magnesium lime of 3.6kg/t half steel then and blow stirring 3 minutes again, carry out pushing off the slag then and come out of the stove.From tapping to 25% the process that begins to tap, in ladle, add the ferro-aluminum reductor of 2.4kg/t steel, the ferrosilicon, the ferromanganese of 8.4kg/t steel, the low carbon ferrochromium of 43kg/t steel and the carburelant steel of 0.44kg/t that in the process of tapping 25～35%, add the 1.84kg/t steel carry out molten steel alloying and carburetting.Wherein, low carbon ferrochromium is that weight ratio is 1: 1 FeCr
69C
0.25And FeCr
55C
25The refining slag that in the process of tapping 35～45%, adds first 4.8kg/t steel.The interior liquid steel temperature of back ladle of having tapped is 1548 ℃; Again in ladle behind the Argon 5min temperature be 1544 ℃; Wherein Argon intensity is 3.4NL/ ton molten steel minute; Thereby obtain the molten steel of deoxidation alloying, the Cr content in the molten steel of this deoxidation alloying is 2.65%, and the yield of above-mentioned low carbon ferrochromium is 97.5%.
Molten steel behind the deoxidation alloying through LF stove ladle refining, is promptly carried out electrically heated and trimming and handles in the LF stove.Ladle adds second batch of refining slag and deoxidation aluminum shot during to the LF stove, and wherein, the add-on of refining slag and deoxidation aluminum shot is respectively 1.18kg/t molten steel and 0.23kg/t molten steel, begins the electrically heated of LF stove then.After the second batch of refining slag fusion that adds, add the 3rd batch of refining slag and deoxidation aluminum shot, the add-on of refining slag and ferro-aluminum reductor is respectively 0.7kg/t molten steel and 0.41kg/t molten steel.After treating the 3rd batch of refining slag fusion, heating molten steel to needs temperature.The treatment time of LF stove ladle refining is 54 minutes, and the Cr content in the molten steel after the processing is 2.65%.
Ladle behind the LF stove ladle refining is carried out the RH vacuum refinement.In the vacuum refinement process, the flow of driving gas is 1300NL/ minute, and handles 12 minutes under less than the situation of 3mbar in vacuum tightness; Keep vacuum tightness then, and require various alloys of adding and carburelant to carry out alloying and carburetting according to steel grades.Alloy comprises ferrosilicon, ferromanganese.The composition of said ferrosilicon, said ferromanganese and said carburelant is identical with the composition of ferrosilicon, ferromanganese and carburelant that when tapping adds, and add-on is respectively 1.0kg/ ton molten steel, 0.48kg/ ton molten steel and 0.45kg/ ton molten steel.Circular treatment is 5 minutes after the alloying, so that composition evenly also finally obtains high chromium steel water, the mass percent of composition is C:0.14%, Si:0.25%; Mn:0.51%, S:0.005%, P:0.009%, Cr:2.65%; Mo:0.40%, full aluminium: 0.04%, all the other are Fe.
This shows; Owing to add high carbon ferro-chrome and low carbon ferrochromium several times among the embodiment 1-3; Thereby when the each Cr of increasing content, obtain higher yield (ratio of the amount of the chromium in the amount that is increased to the chromium in the molten steel composition and the ferrochrome that is added); And need not add too many low carbon ferrochromium, thereby reduce cost.On the contrary, Comparative Examples is disposable when deoxidation alloying is carried out in tapping to have added a large amount of low carbon ferrochromiums, and not only yield is lower and cause the heat-up time and the treatment time of follow-up LF stove ladle refining longer, has increased production cost greatly.Therefore, method of the present invention can significantly reduce cost, and what help producing carries out continuously.
Need to prove that each the concrete technical characterictic described in above-mentioned embodiment can carry out arbitrary combination through any suitable manner, it falls within the disclosed scope of the present invention equally.In addition, also can carry out arbitrary combination between the various embodiment of the present invention, as long as it is without prejudice to thought of the present invention, it should be regarded as the disclosed content of the present invention equally.
More than describe preferred implementation of the present invention in detail; But the present invention is not limited to the detail in the above-mentioned embodiment, in technical conceive scope of the present invention; Can carry out multiple simple variant to technical scheme of the present invention, these simple variant all belong to protection scope of the present invention.
Claims (12)
1. method of smelting high chromium steel, this method comprises:
In converter, molten iron is carried out refining just;
Molten steel after the refining is just tapped in the ladle, in tapping process, add high carbon ferro-chrome, make that the Cr content in the molten steel reaches 1.8～2.4 weight %;
Ladle is carried out LF stove ladle refining, in LF stove ladle refining process, add low carbon ferrochromium, the weight ratio in the add-on of chromium content of said low carbon ferrochromium and said high carbon ferro-chrome is 1: 2～1: 3.5;
Molten steel to behind the LF stove ladle refining carries out the RH vacuum refinement.
2. the method for smelting high chromium steel according to claim 1 wherein, in the step that adds high carbon ferro-chrome, makes that the Cr content in the molten steel reaches 2.0～2.2 weight %.
3. the method for smelting high chromium steel according to claim 1, wherein, said high carbon ferro-chrome is FeCr
67C
6.0, FeCr
55C
600, FeCr
67C
9.5, FeCr
55C
1000In at least a; Said low carbon ferrochromium is FeCr
69C
0.25, FeCr
55C
25, FeCr
69C
0.50, FeCr
55C
50In at least a.
4. the method for smelting high chromium steel according to claim 1, wherein, the add-on of said high carbon ferro-chrome is 30～40kg/ ton molten steel, the add-on of said low carbon ferrochromium is 10～15kg/ ton molten steel.
5. the method for smelting high chromium steel according to claim 1 wherein, added said high carbon ferro-chrome at 20～40% o'clock in tapping.
6. the method for smelting high chromium steel according to claim 1, wherein, this method is included in and adds low carbon ferrochromium when carrying out the RH vacuum refinement, and the add-on of this low carbon ferrochromium is smaller or equal to 3kg/ ton molten steel and greater than 0.
7. the method for smelting high chromium steel according to claim 1, wherein, said molten iron is a half steel; The mass percent of the composition of this half steel is C:3.5～3.8%, V:0.025～0.036%, Mn:0.03～0.07%; Cr:0.04～0.06%; S:0.002～0.005%, P:0.04～0.07%, Fe:95.96～96.36%.
8. the method for smelting high chromium steel according to claim 7; Wherein, just making steel the mass percent of composition of water is: C:0.035～0.050%, Mn:0.01～0.04%; Cr:0.03～0.04%; P:0.004～0.006%, S:0.003～0.006%, Fe:99.86～99.91%.
9. according to the method for any described smelting high chromium steel among the claim 1-8, wherein, this method comprises: before adding said high carbon ferro-chrome, in tapping to 20～30% process, add the duraluminum reductor of 2.2～2.8kg/ ton molten steel; After adding said high carbon ferro-chrome, in tapping to 30～50% process, add the refining slag of 4.6～5.2kg/ ton molten steel; After tapping is accomplished and before LF stove ladle refining, add the refining slag of 1.13～1.2kg/ ton molten steel and the deoxidation aluminum shot of 0.15～0.22kg/ ton molten steel; In LF stove ladle refining heat-processed, add the refining slag of 0.7～1.02kg/ ton molten steel and the deoxidation aluminum shot of 0.08～0.4kg/ ton molten steel in ladle slag fusing back.
10. the method for smelting high chromium steel according to claim 9, wherein, the mass percent of the composition of said refining slag is: CaO:70～80%, Al
2O
3: 2～8%, MgO:0～5%, SiO
2: 0～3%, Na
2O:3～5%, CaF
2: 8～14%; The mass percent of the composition of said duraluminum reductor is: Al:38～50%, Fe:50～62%; The mass percent of the composition of said deoxidation aluminum shot is Al:95～99%, Al
2O
3: 1～5%.
11. one kind by any high chromium steel that described method is smelted among the claim 1-10.
12. high chromium steel according to claim 11, wherein, the mass percent of the composition of said high chromium steel is C:0.15～0.20%; Si:0.15～0.30%, Mn:0.45～0.60%, S:0.002～0.008%; P:0.004～0.008%, Cr:2.8～3.2%, Mo:0.40～0.50%; Full aluminium: 0.01～0.04%, Fe:95.2～95.98%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201010523393 CN102453831B (en) | 2010-10-26 | 2010-10-26 | Method for smelting high-chromium steel and high-chromium steel |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201010523393 CN102453831B (en) | 2010-10-26 | 2010-10-26 | Method for smelting high-chromium steel and high-chromium steel |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102453831A true CN102453831A (en) | 2012-05-16 |
| CN102453831B CN102453831B (en) | 2013-04-10 |
Family
ID=46037520
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201010523393 Active CN102453831B (en) | 2010-10-26 | 2010-10-26 | Method for smelting high-chromium steel and high-chromium steel |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102453831B (en) |
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102703644A (en) * | 2012-06-25 | 2012-10-03 | 武汉钢铁(集团)公司 | Method for producing low-carbon high-chrome alloy steel |
| CN103045948A (en) * | 2012-12-26 | 2013-04-17 | 攀钢集团攀枝花钢钒有限公司 | High-chromium steel and manufacturing method thereof |
| CN103627973A (en) * | 2013-11-25 | 2014-03-12 | 攀钢集团攀枝花钢铁研究院有限公司 | Production method for low-carbon high-chromium steel |
| CN103642967A (en) * | 2013-11-18 | 2014-03-19 | 攀钢集团攀枝花钢铁研究院有限公司 | Method for producing high-chromium steel by converter |
| CN104046738A (en) * | 2014-02-13 | 2014-09-17 | 攀钢集团攀枝花钢铁研究院有限公司 | Smelting method of ultralow-sulfur high-chromium steel and ultralow-sulfur high-chromium steel prepared by smelting method |
| CN104862577A (en) * | 2014-10-14 | 2015-08-26 | 长春工业大学 | Method for manufacturing high-nitrogen steel by utilization of carbon-containing ferrochrome |
| CN104946845A (en) * | 2015-07-30 | 2015-09-30 | 攀钢集团攀枝花钢钒有限公司 | Method for producing high-carbon-chrome bearing steel from vanadium-titanium-containing molten iron |
| CN105483309A (en) * | 2014-09-19 | 2016-04-13 | 鞍钢股份有限公司 | Alloy addition method for smelting chromium-containing alloy steel through converter |
| CN105648342A (en) * | 2016-02-26 | 2016-06-08 | 铜陵安东铸钢有限责任公司 | Wear-resistant high-chromium steel and manufacturing method thereof |
| CN106048427A (en) * | 2016-06-13 | 2016-10-26 | 攀钢集团攀枝花钢钒有限公司 | Nickel-containing and boron-containing gear steel and production method thereof |
| CN106755709A (en) * | 2016-11-25 | 2017-05-31 | 江苏省沙钢钢铁研究院有限公司 | Chromium method is matched somebody with somebody in a kind of converter of low-carbon (LC) containing Cr steel alloys |
| CN114032473A (en) * | 2021-11-29 | 2022-02-11 | 东北大学 | Alloy adding method of coating-free hot forming steel |
| WO2023093112A1 (en) * | 2021-11-29 | 2023-06-01 | 东北大学 | Smelting and continuous casting method for high-cr-si alloyed hot-formed steel |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1204697A (en) * | 1997-04-29 | 1999-01-13 | 奥瓦科钢铁股份公司 | Nitriding steel |
| JP2000345281A (en) * | 1999-06-02 | 2000-12-12 | Nippon Steel Corp | Low alloy heat resistant steel excellent in weldability and low temperature toughness, and its production |
-
2010
- 2010-10-26 CN CN 201010523393 patent/CN102453831B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1204697A (en) * | 1997-04-29 | 1999-01-13 | 奥瓦科钢铁股份公司 | Nitriding steel |
| JP2000345281A (en) * | 1999-06-02 | 2000-12-12 | Nippon Steel Corp | Low alloy heat resistant steel excellent in weldability and low temperature toughness, and its production |
Cited By (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102703644B (en) * | 2012-06-25 | 2014-03-12 | 武汉钢铁(集团)公司 | Method for producing low-carbon high-chrome alloy steel |
| CN102703644A (en) * | 2012-06-25 | 2012-10-03 | 武汉钢铁(集团)公司 | Method for producing low-carbon high-chrome alloy steel |
| CN103045948A (en) * | 2012-12-26 | 2013-04-17 | 攀钢集团攀枝花钢钒有限公司 | High-chromium steel and manufacturing method thereof |
| CN103045948B (en) * | 2012-12-26 | 2014-12-31 | 攀钢集团攀枝花钢钒有限公司 | High-chromium steel and manufacturing method thereof |
| CN103642967A (en) * | 2013-11-18 | 2014-03-19 | 攀钢集团攀枝花钢铁研究院有限公司 | Method for producing high-chromium steel by converter |
| CN103627973A (en) * | 2013-11-25 | 2014-03-12 | 攀钢集团攀枝花钢铁研究院有限公司 | Production method for low-carbon high-chromium steel |
| CN103627973B (en) * | 2013-11-25 | 2015-11-18 | 攀钢集团攀枝花钢铁研究院有限公司 | A kind of production method of low-carbon high-chromium steel |
| CN104046738A (en) * | 2014-02-13 | 2014-09-17 | 攀钢集团攀枝花钢铁研究院有限公司 | Smelting method of ultralow-sulfur high-chromium steel and ultralow-sulfur high-chromium steel prepared by smelting method |
| CN104046738B (en) * | 2014-02-13 | 2015-12-09 | 攀钢集团攀枝花钢铁研究院有限公司 | A kind of smelting process of super low sulfur high chromium steel and the super low sulfur high chromium steel of preparation thereof |
| CN105483309A (en) * | 2014-09-19 | 2016-04-13 | 鞍钢股份有限公司 | Alloy addition method for smelting chromium-containing alloy steel through converter |
| CN104862577A (en) * | 2014-10-14 | 2015-08-26 | 长春工业大学 | Method for manufacturing high-nitrogen steel by utilization of carbon-containing ferrochrome |
| CN104946845A (en) * | 2015-07-30 | 2015-09-30 | 攀钢集团攀枝花钢钒有限公司 | Method for producing high-carbon-chrome bearing steel from vanadium-titanium-containing molten iron |
| CN105648342A (en) * | 2016-02-26 | 2016-06-08 | 铜陵安东铸钢有限责任公司 | Wear-resistant high-chromium steel and manufacturing method thereof |
| CN106048427A (en) * | 2016-06-13 | 2016-10-26 | 攀钢集团攀枝花钢钒有限公司 | Nickel-containing and boron-containing gear steel and production method thereof |
| CN106048427B (en) * | 2016-06-13 | 2019-02-19 | 攀钢集团攀枝花钢钒有限公司 | Nickeliferous, boracic pinion steel and its production method |
| CN106755709A (en) * | 2016-11-25 | 2017-05-31 | 江苏省沙钢钢铁研究院有限公司 | Chromium method is matched somebody with somebody in a kind of converter of low-carbon (LC) containing Cr steel alloys |
| CN106755709B (en) * | 2016-11-25 | 2019-02-01 | 江苏省沙钢钢铁研究院有限公司 | Chromium method is matched in a kind of converter of low-carbon steel alloy containing Cr |
| CN114032473A (en) * | 2021-11-29 | 2022-02-11 | 东北大学 | Alloy adding method of coating-free hot forming steel |
| WO2023093112A1 (en) * | 2021-11-29 | 2023-06-01 | 东北大学 | Smelting and continuous casting method for high-cr-si alloyed hot-formed steel |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102453831B (en) | 2013-04-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102453831B (en) | Method for smelting high-chromium steel and high-chromium steel | |
| CN103469093B (en) | A kind of containing molybdenum stainless steel and smelting process thereof | |
| CN103014537B (en) | Smelting method of steel used in high speed passenger train hollow axle | |
| CN102383055B (en) | Production method for reducing titanium content in high-carbon chromium bearing steel | |
| CN103627842B (en) | Method for enhancing end point carbon content in smelting medium-carbon steel from semisteel and semisteel steelmaking method | |
| CN103627973B (en) | A kind of production method of low-carbon high-chromium steel | |
| CN102766726A (en) | Method for smelting stainless steel by high-chrome melt and dephosphorized pre-melt | |
| CN106811567B (en) | A method of producing low manganess steel | |
| CN103642971B (en) | Improve method and the Semi-steel making method of semi-steel making endpoint carbon content | |
| CN101979672A (en) | Method for ultra-deeply dephosphorizing in steel ladle | |
| CN102719726B (en) | Method for producing stainless steel master liquid | |
| CN101671763A (en) | Method for increasing nitrogen for smelting high nitrogen stainless steel in argon oxygen decarburizing furnace | |
| CN108103261A (en) | A kind of mini-mill steelmaking method based on converter | |
| CN103627839B (en) | Semisteel steelmaking carbon content control method and semisteel steelmaking method | |
| CN103627971A (en) | Alloy structural steel for large-specification soldering tools and smelting method thereof | |
| CN103255356B (en) | Method for preparing low-carbon stainless steel | |
| CN102312035A (en) | Smelting method for producing high strength weathering steel by use of chromium-nickel pig iron | |
| CN104046738B (en) | A kind of smelting process of super low sulfur high chromium steel and the super low sulfur high chromium steel of preparation thereof | |
| CN103642966B (en) | Method for improving high-carbon high-manganese steel converter smelting endpoint carbon content and steelmaking method | |
| CN103627851B (en) | Semisteel steelmaking temperature control method and semisteel steelmaking method | |
| CN104946845B (en) | Method for producing high-carbon-chrome bearing steel from vanadium-titanium-containing molten iron | |
| CN101736123B (en) | Boron-containing alloy smelting process with high yield | |
| CN103388099A (en) | Method for smelting austenite stainless steel by using dephosphorized molten iron | |
| CN106048427B (en) | Nickeliferous, boracic pinion steel and its production method | |
| CN107619899A (en) | A kind of production method and Steel material of low remaining chromium content molten steel |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |