CN105779780B - A kind of electroslag remelting free-floride slag and its method for electroslag remelting - Google Patents
A kind of electroslag remelting free-floride slag and its method for electroslag remelting Download PDFInfo
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- CN105779780B CN105779780B CN201610368052.3A CN201610368052A CN105779780B CN 105779780 B CN105779780 B CN 105779780B CN 201610368052 A CN201610368052 A CN 201610368052A CN 105779780 B CN105779780 B CN 105779780B
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B9/00—General processes of refining or remelting of metals; Apparatus for electroslag or arc remelting of metals
- C22B9/16—Remelting metals
- C22B9/18—Electroslag remelting
Abstract
The present invention provides a kind of electroslag remelting free-floride slag and its method for electroslag remelting, the floride-free cinder ladle and includes the component of following parts by weight：45~55 parts of CaO, 35~45 parts of Al2O3, 5~10 parts of MgO and 2~5 part of SiO2；Methods described bakees above-mentioned floride-free slag, assemble electroslag refining furnace, floride-free slag and the deoxidier starting the arc bakeed is first added into the crystallizer of electroslag refining furnace, with graphite electrode starting the arc slag making, change graphite electrode into consumable electrode melting again, voltage 51 ~ 54V, 7700 ~ 8100A of electric current be set, energization seasoning metal, adds aluminium powder in reflow process and carries out deoxidation.The floride-free slag of the present invention can reduce the pollution to environment in esr process, and and can ensures the good ingot casting shaping of electroslag remelting, any surface finish, ingotism degree is small, dense structure is uniform and gas content is low.
Description
Technical field
The invention belongs to Summoning material electrometallurgy technical field, it is related to electrometallurgy technical field, and in particular to Yi Zhong electricity
Slag remelting free-floride slag and its method for electroslag remelting.
Background technology
It is well known that electroslag remelting process steel-making is one of important means for producing superior alloy steel and alloy, remelting slag
Had a very important role from esr process, it can also control gold in addition to the thermal source as consutrode
The chemical composition of category, refining liquid steel, removal non-metallic inclusion.AH Φ -6 slags are widely used for a long time both at home and abroad（CaF2 70%+
Al2O330%）.It is currently used with CaF2Higher than conductance for the high fluorine remelting slag of base, slag caloric value is insufficient, in reflow process
Slag composition is unstable, and then influences the stability of remelting processing, and it is due to containing substantial amounts of CaF2, have in fusion process
HF、SiF4、AlF3Escaped Deng a large amount of volatile fluoro-gas, seriously pollute environment, be detrimental to health, certain be good for be present
Health hidden danger, Green Development requirement is not met.
Metallargist is also developing floride-free remelting slag in recent years, and main exploitation has CaO-Al2O3And CaO-Al2O3-SiO2
Floride-free slag, used CaO：Al2O3Mass ratio is all 1:1, related data and phasor introduction, can it be formed just stably
12CaO·7Al2O3Eutectic composition.2580 DEG C of CaO fusing point, Al2O32050 DEG C of fusing point, fusing point differs greatly, and electroslag weight
Molten process is carried out under conditions of strong cooling, therefore the high CaO of fusing point is prior to low-melting Al2O3In crystallizer inwall
Solidification, with the progress of melting, CaO is fewer and fewer, cannot preferably form stable 12CaO7Al2O3.So use
CaO：Al2O3Mass ratio is all 1:The floride-free slag of 1 proportioning, slag crust minimal thickness is uneven in actual production, has a strong impact on steel ingot table
Face finish etc., certain weak point be present.
The content of the invention
For deficiencies of the prior art, the technical problem to be solved in the present invention is：For containing in the prior art
Fluorine slag influences the stability of remelting processing and pollutes environment, is detrimental to health, and floride-free slag melting point is high, conductance is low, ignites
Difficulty, carries out that the The ingot casting thickness that electroslag remelting obtains is uneven, has a strong impact on surface of steel ingot finish using existing floride-free slag
Technical problem, and provide a kind of pollution that can be reduced to environment, and can ensures that the ingot casting shaping of electroslag remelting is good, surface light
Electroslag remelting free-floride slag clean, ingotism degree is small, dense structure is uniform and gas content is low and its for electroslag remelting
Method.
In order to solve the above-mentioned technical problem, the present invention adopts the following technical scheme that：A kind of electroslag remelting free-floride slag, including such as
The component of lower parts by weight：45~55 parts of CaO, 35~45 parts of Al2O3, 5~10 parts of MgO and 2~5 part of SiO2。
Using the floride-free slag so matched, the MgO and SiO of addition2With the CaO and Al of a substitution part2O3, make melting
Slag ingredient and technical process in journey it is more stable；Wherein, SiO2It can reduce the gas permeability of slag, contain nitrogen in steel, hydrogen, oxygen
Amount reduces；And a small amount of MgO forms half solidification film on slag bath surface, reduce the oxide that appraised at the current rate in slag bath suction hydrogen and slag and melted to metal
Transmit the possibility of oxygen in pond.The CaO lost is solidified under strong cool condition in order to make up fusion process, invention increases certain
The CaO of amount component, i.e. CaO：Al2O3Mass ratio control 1.2：Between 1.3, so, be advantageous to be formed under melting high temperature
Stable 12CaO7Al2O3For cocrystalization compound without decomposing, fusion process is more stable, makes to carry out electroslag using the floride-free slag
The steel ingot shaping obtained after remelting is more preferably, surface is brighter and cleaner, ingotism degree is small.
Further, the electroslag remelting free-floride cinder ladle includes the component of following parts by weight：50 parts of CaO, 40 parts of Al2O3, 7 parts of MgO
With 3 parts of SiO2.Using the floride-free slag of such optimum ratio, nitrogen in ingot casting, hydrogen, oxygen content can be effectively reduced, makes to prolong in steel
Stretching property oxide, sulfide content are greatly reduced, and obtained steel ingot non-nuclear density gauge, metal structure are finer and close, uniform.
The method that electroslag remelting is carried out using the electroslag remelting free-floride slag, is comprised the following steps：
1）Above-mentioned electroslag remelting free-floride slag is bakeed 8 ~ 10 hours at 800 ~ 900 DEG C in stove, that is, takes and uses；
2）Consutrode is welded on dummy electrode, assembles electroslag refining furnace, to the crystallizer of the electroslag refining furnace
Middle addition deoxidier and step 1）The floride-free slag bakeed, with the graphite electrode starting the arc, observe after color becomes bright in crystallizer stove
After 7 ~ 12 minutes, graphite electrode is taken out；The deoxidier includes aluminium powder and silicon calcium powder, the aluminium powder, silicon calcium powder and floride-free slag
Mass ratio be 0.2 ~ 0.5:0.3~0.7:100；
3）Step 2）After slag making terminates, change graphite electrode into consumable electrode melting, 51 ~ 54V of voltage, electric current 7700 are set
~ 8100A, energization seasoning metal, aluminium powder is added in reflow process and carries out deoxidation, wherein, the addition of aluminium powder is to be described from power consumption
The 0.025 ~ 0.07% of pole weight.
Electro-slag re-melting method of the present invention is for electroslag remelting free-floride slag method especially set out, because of nothing of the present invention
The fusing point of fluorine slag is higher than about 100 ~ 200 degree of other slag system species fusing points, starting the arc relative difficulty, and the present invention creatively uses graphite
Electrode carrys out the starting the arc, makes slag system conductive effect more preferable using graphite electrode, it is easier to the starting the arc, to shorten arcing time and difficulty.Pin
It is low to the ratio conduction of the floride-free slag of the present invention, the problem of electrode melting is fast, metal bath deepens is easily caused in electroslag remelting, this
Invention selects offline parameter value in 51 ~ 54V of voltage, 7700 ~ 8100A of electric current to carry out electroslag remelting, makes electrode melting speed phase
It should slow down, be effectively ensured that purification efficiency of the consutrode in reflow process is high, the cooled and solidified speed of metal bath is more suitable,
The ingot casting shaping that further ensures electroslag remelting is good, any surface finish, ingotism degree are small, dense structure uniformly and gas contains
Measure low.
Further, step 2）It is middle to use the graphite electrode starting the arc, 10 minutes again after color becomes bright in crystallizer stove, take out graphite
Electrode.It so more can guarantee that the fusing of floride-free slag is complete, it is ensured that higher slag bath temperature, and then during making consumable electrode melting
Purification efficiency is higher.
As optimization, step 2）Described in aluminium powder, silicon calcium powder and floride-free slag mass ratio be 0.3: 0.6:100.Add silicon
Calcium powder is 2 times of aluminium powder amount, can guarantee that the oxide in slag fully removes, moreover it is possible to becomes containing for aluminum oxide after reducing aluminium scaling loss
Amount, the purification efficiency of consutrode remelting is effectively ensured.
As optimization, step 3）Middle setting voltage 52V, electric current 7800A energization seasoning metals.In offline voltage,
Current parameters value, flat metal bath shape can be preferably obtained, this is advantageous to secondary distance between axles and diminished, and reduces micro- inclined
Analysis, make ingot structure densification, composition uniform.
As another optimization, step 3）The addition of aluminium powder is the 0.05% of the consutrode weight.Using such addition
The aluminium powder of amount both ensure that the reproducibility of slag, also reduce alumina inclusion in steel, ensure that the stable melting of consutrode.
As another optimization, the material of the consutrode is austenitic stainless steel or structural alloy steel.The present invention uses
The method that floride-free slag carries out electroslag remelting especially creates unexpected effect to austenitic stainless steel or structural alloy steel, makes
This two classes steel grade ingot casting shaping effect is good, and any surface finish, desulfuration effect is good, and the extensibility sulfide and oxide in steel reduce aobvious
Write.
Compared with prior art, the present invention has the advantages that：
Surface of steel ingot that 1st, fluoride-free slag of the present invention can obtain remelting by the collaboration compatibility effect of each component is bright and clean,
Ingotism degree is small, even tissue is fine and close, gas content is low in steel, overcomes the The ingot casting thickness that prior art free-floride slag obtains
Uneven, poor surface smoothness technical problem.
2nd, the floride-free slag electrical conductivity height of the present invention, power consumption substantially reduce, and can give full play to the latent of existing electroslag remelting equipment
Power, substantially reduce production cost.
3rd, the floride-free slag of the present invention is compared with the fluorine-containing slag system of prior art, and will not being volatilized in esr process, it is poisonous to produce
Fluoride, and then do not pollute the environment and be detrimental to health, more with green environmental protection.
4th, existing conventional electroslag remelting equipment can be used by carrying out electroslag remelting using the floride-free slag of the present invention, without extra
Input introduces new equipment, is convenient for promoting, market application foreground is good.
Embodiment
The present invention is described in further detail with reference to specific embodiment.The implementation case using the technology of the present invention as
Under the premise of implemented, now provide detailed embodiment and specific operating process illustrate the present invention it is creative, but
Protection scope of the present invention is not limited to following embodiment.
The electroslag remelting of embodiment 1 produces 30CrMnSiA alloys
A kind of electroslag remelting free-floride slag, include the component of following parts by weight：50 parts of CaO, 40 parts of Al2O3, 7 parts MgO and 3 part
SiO2。
30CrMnSiA steel alloys are produced using above-mentioned electroslag remelting free-floride slag remelting, specifically with the following method：
1）Raw material is weighed according to above-mentioned electroslag remelting free-floride slag, by Al2O3→CaO→SiO2→ MgO loading sequence loads
In slag box, in 800 DEG C of afterheat bakings 8 hours, the moisture in slag charge is fully removed.
2）∮ 240mm 30CrMnSiA consutrode bases are welded on dummy electrode；
3）With the graphite electrode starting the arc, fluoride-free slag of igniting, operator observes slag charge fusing situation in crystallizer, treats face in stove
After discoloration is bright, re-melting 9 minutes, graphite electrode is lifted, insert consutrode remelting.Al powder 150 is added in the process
The g of g, Si-Ca powder 300, the i.e. mass ratio of aluminium powder, silicon calcium powder and floride-free slag are 0.3: 0.6:100.
4）Step 3）Consutrode base is inserted in slag charge after slag charge fusing completely, regulation electric current is 7800A, adjusts voltage
For 52V, energization seasoning metal, aluminium powder is added in reflow process and carries out deoxidation, Al is uniformly added into every 4 minutes addition 6g speed
Powder, addition total amount are the 0.05% of 250g, as consutrode weight.
5）Using reduction current system feeding step by step.After feeding terminates power-off, cooled down 45 minutes in crystallizer, the demoulding is sent
Enter to add stay-warm case, obtain 30CrMnSiA alloy steel ingots.
The electroslag remelting of embodiment 2 produces 0Cr18Ni9 alloys
A kind of electroslag remelting free-floride slag, include the component of following parts by weight：48 parts of CaO, 42 parts of Al2O3, 5 parts MgO and 5 part
SiO2。
0Cr18Ni9 alloys are produced using above-mentioned electroslag remelting free-floride slag remelting, specifically with the following method：
1）Raw material is weighed according to above-mentioned electroslag remelting free-floride slag, by Al2O3→CaO→SiO2→ MgO loading sequence loads
In slag box, in 900 DEG C of afterheat bakings 10 hours, the moisture in slag charge is fully removed.
2）∮ 240mm 0Cr18Ni9 consutrode bases are welded on dummy electrode；
3）With the graphite electrode starting the arc, fluoride-free slag of igniting, operator observes slag charge fusing situation in crystallizer, treats face in stove
After discoloration is bright, re-melting 10 minutes, graphite electrode is lifted, insert consutrode remelting.Al powder 170 is added in the process
The g of g, Si-Ca powder 340, the i.e. mass ratio of aluminium powder, silicon calcium powder and floride-free slag are 0.34：0.68：100.
4）Step 3）Consutrode base is inserted in slag charge after slag charge fusing completely, regulation electric current is 7900A, adjusts voltage
For 51V, energization seasoning metal, aluminium powder is added in reflow process and carries out deoxidation, Al is uniformly added into every 5 minutes addition 8g speed
Powder, it is the 0.056% of 280g, as consutrode weight that Al powder, which adds total amount,.
5）Using reduction current system feeding step by step.After feeding terminates power-off, cooled down 60 minutes in crystallizer, after the demoulding
Air cooling, obtain 0Cr18Ni9 alloy steel ingots.
The effect example of embodiment 3
30CrMnSiA, 0Cr18Ni9 assay obtained to Examples 1 and 2 see the table below：
The testing result of table 1
Molecule is minimum value and maximum in the sulfide of upper table 1 and oxide detection data, and denominator is average value.By upper table
1 can be seen that：The steel ingot obtained after remelting has reduction than the content of the nitrogen of consutrode base, hydrogen, oxygen；It is center porosity, general
Segregation and pattern segregation reach standard requirement at 0 ~ 0.5 grade；Extensibility oxide, the content of sulfide also significantly drop in steel
It is low.0Cr18Ni9,30CrMnSiA the electroslag ingot non-nuclear density gauge obtained in addition using the floride-free slag of the present invention, metal structure
It is fine and close, uniform.Therefore excellent remelting effect can be reached using the inventive method.
Finally illustrate, the above embodiments are merely illustrative of the technical solutions of the present invention and it is unrestricted, although with reference to compared with
The present invention is described in detail good embodiment, it will be understood by those within the art that, can be to the skill of the present invention
Art scheme is modified or equivalent substitution, and without departing from the objective and scope of technical solution of the present invention, it all should cover at this
Among the right of invention.
Claims (6)
1. a kind of method that electroslag remelting free-floride slag carries out electroslag remelting, it is characterised in that specifically comprise the following steps：
1）Electroslag remelting free-floride slag is bakeed 8 ~ 10 hours at 800 ~ 900 DEG C in stove；
2）Consutrode is welded on dummy electrode, assembles electroslag refining furnace, is added into the crystallizer of the electroslag refining furnace
Enter deoxidier and step 1）The floride-free slag bakeed, with the graphite electrode starting the arc, observe after color becomes bright in crystallizer stove after 7
~ 12 minutes, take out graphite electrode；The deoxidier includes aluminium powder and silicon calcium powder, the quality of the aluminium powder, silicon calcium powder and floride-free slag
Than for 0.2 ~ 0.5:0.3~0.7:100；
3）Step 2）After slag making terminates, change graphite electrode into consumable electrode melting, set 51 ~ 54V of voltage, electric current 7700 ~
8100A, energization seasoning metal, aluminium powder is added in reflow process and carries out deoxidation, wherein, the addition of aluminium powder is the consutrode
The 0.025 ~ 0.07% of weight；The material of the consutrode is austenitic stainless steel or structural alloy steel；
The electroslag remelting free-floride cinder ladle includes the component of following parts by weight：45~55 parts of CaO, 35~45 parts of Al2O3, 5~10 parts
MgO and 2~5 part of SiO2, the CaO and Al2O3Quality be 1.25：1.
2. the method that electroslag remelting free-floride slag carries out electroslag remelting according to claim 1, it is characterised in that the electroslag weight
Melt the component that floride-free cinder ladle includes following parts by weight：50 parts of CaO, 40 parts of Al2O3, 7 parts of MgO and 3 part of SiO2。
3. the method for electroslag remelting according to claim 1, it is characterised in that step 2）It is middle to use the graphite electrode starting the arc, crystallization
10 minutes again after color becomes bright in device stove, graphite electrode is taken out.
4. the method for electroslag remelting according to claim 1, it is characterised in that step 2）Described in aluminium powder, silicon calcium powder and nothing
The mass ratio of fluorine slag is 0.3: 0.6:100.
5. the method for electroslag remelting according to claim 1, it is characterised in that step 3）Middle setting voltage 52V, electric current
7800A energization seasoning metals.
6. the method for electroslag remelting according to claim 1, it is characterised in that step 3）The addition of aluminium powder is the consumable
The 0.05% of electrode weight.
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| CN107858525B (en) * | 2017-05-18 | 2020-06-12 | 邢台树志冶金科技有限公司 | Electroslag remelting fluorine-free slag process formula and method for electroslag remelting |
| CN108265179B (en) * | 2017-12-07 | 2019-12-17 | 山西太钢不锈钢股份有限公司 | Electrode blank exchange remelting method |
| CN109161696B (en) * | 2018-09-30 | 2020-06-30 | 重庆钢铁(集团)有限责任公司 | Electroslag remelting slag system and low-oxygen control method for electroslag remelting Fe-Cr-Al alloy |
| CN109055770A (en) * | 2018-09-30 | 2018-12-21 | 重庆钢铁(集团)有限责任公司 | A kind of electroslag remelting slag and it is used for electroslag remelting 40CrNiMoA low hydrogen control method |
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| CN103667732B (en) * | 2012-09-12 | 2016-01-20 | 上海丰渠特种合金有限公司 | A kind of method of esr |
| CN104561570B (en) * | 2013-09-25 | 2016-08-17 | 安徽工业大学 | A kind of efficient using method utilizing the electroslag remelting refining slag returning slag |
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