CN103074467A - Solid metal magnesium alloy core-spun yarn for steelmaking desulfuration and manufacture method of solid metal magnesium alloy core-spun yarn - Google Patents
Solid metal magnesium alloy core-spun yarn for steelmaking desulfuration and manufacture method of solid metal magnesium alloy core-spun yarn Download PDFInfo
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- CN103074467A CN103074467A CN2013100449961A CN201310044996A CN103074467A CN 103074467 A CN103074467 A CN 103074467A CN 2013100449961 A CN2013100449961 A CN 2013100449961A CN 201310044996 A CN201310044996 A CN 201310044996A CN 103074467 A CN103074467 A CN 103074467A
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Abstract
The invention discloses a solid metal magnesium alloy core-spun yarn for steelmaking desulfuration. The solid metal magnesium alloy core-spun yarn comprises an external-layer steel pipe, an intermediate passivation layer and an internal core, wherein the internal core is a solid metal magnesium alloy wire with the total weight sum of impurities of not more than 0.2wt percent. A method for manufacturing the solid metal magnesium alloy core-spun yarn for steelmaking desulfuration comprises the following steps of: simultaneously sending the solid metal magnesium alloy wire and a steel belt into an argon arc welding unit, compacting, welding and drawing to form the internal core, and making the steel belt into a seamless steel pipe to be used as an external layer for wrapping the internal core. According to the solid metal magnesium alloy core-spun yarn, the gasification speed of metal magnesium can be reduced, the insertion depth of the magnesium alloy wire and the time of absorbing the metal magnesium by molten steel are increased, the quantity of the magnesium participating in the reaction is increased, the problem of low yield of magnesium power is overcome, harmful elements in the magnesium powder are avoided being dragged in, and thus the yield of the metal magnesium is greatly increased.
Description
Technical field
The present invention relates to metallurgical technology field, particularly relate to a kind of solid metal Mg alloy cored wine for steel desulfurization and preparation method thereof.
Background technology
Magnesium is silvery white in color, and belongs to alkali earth metal, its chemical reaction than other alkaline-earth metal such as K, Na, Ca a little less than, easily generate MgO, MgS with association reactions such as many elements such as O, N, S.These two kinds of oxide compounds are the stable compound that fusing point is high, proportion is little.Mg adds the transition process that will experience Mg (s) → Mg (l) → Mg (g) → [Mg] in the molten steel, dissolves, deoxidation, desulphurization reaction, partly will scaling loss in the process of adding.And the boiling point of Mg is low, vapour pressure is high, and the solubleness during 1873K in molten steel is 0.1%, vapour pressure is 2.238MPa, and so high vapour pressure makes magnesium enter immediately vaporization in the molten steel, and outwards gets rid of with very high vaporization rate, therefore, magnesium separately exists in and is difficult to the performance useful effect in the molten steel.The general alloy mode that adopts joins the molten steel depths, is conducive to improve Mg utilization.Non-metallic element has extremely strong avidity in alkaline-earth metal and the molten steel, and Mg is at present main as iron melt desulfurizing agent, cast iron nodulizer at metallurgy industry, and the effect of deoxidation of molten steel, desulfurization and inclusion modification etc. is also lacked unified understanding.In addition, contain certain magnesium in the molten steel and can avoid in steel, forming bunch shape/strip A1
2O
3Be mingled with the MgO.A1 of formation
2O
3Minimum and the stochastic distribution of spinel, harmless to fatigue property and other performances of steel, to compare with the steel that Ca processes, purity is higher.A certain amount of Mg is dissolved in the molten steel in addition, and on oxide spinel, sulphur can be separated out mutually with MgS/MgS-MnS, has avoided the disadvantageous effect of sulfide to steel mechanical property.
The used magnesium of steel desulfurization is magnesium powder or magnesium powder cored-wire at present.Since the magnesium powder be in use with specific equipment with the magnesium powder be injected to molten steel arrive its bottom react, because only 1080 ℃ of the gasification points of magnesium, and the temperature of molten steel reaches about 1500 ℃, when the magnesium powder passes molten steel, the magnesium powder can reach its gasification point moment, form magnesium steam, simultaneously because the surface-area of magnesium powder is excessive, the magnesium that participates in reaction is too much, causes the amount of vaporization of magnesium very large, and the formed magnesium steam of these two reasons is assembled in molten steel, form very large vapour pressure, cause magnesium to be overflowed in a large number from molten steel, cause explosion hazard, some magnesium is scaling loss in stove finally.So not only caused the waste of magnesium, and because magnesium and molten steel are too short duration of contact, the magnesium quantity that participates in reaction reduces, and does not have enough magnesium and the S element in the molten steel fully to react, and can not make the content of S element be down to minimum.
Summary of the invention
Make molten steel magnesium highly-efficient treatment stable for solving the deficiency of existing steel desulfurization spray magnesium powder existence, reaching, the invention provides a kind of solid metal Mg alloy cored wine for steel desulfurization.He can reduce the gasification rate of MAGNESIUM METAL, increase the depth of penetration of magnesium alloy wire and the time that MAGNESIUM METAL is absorbed by molten steel, increase magnesium and participate in corresponsively quantity, overcome magnesium powder recovery rate low, avoid the bringing into of harmful element in the magnesium powder, thereby improved greatly the recovery rate of MAGNESIUM METAL.
For solving the problems of the technologies described above, the present invention adopts following technical scheme: the solid metal Mg alloy cored wine that is used for steel desulfurization, comprise outer layer pipe, intermediate passivation layer and inner core, described inner core is the solid metal magnesium alloy wire of impurity weight summation≤0.2wt%, the composition of described solid metal magnesium alloy wire comprises: magnesium 92-98wt%, aluminium 0.5-3wt%, calcium 0.5-3wt%, rare earth 0.1-0.9wt%, alloy density are 1.73g/cm
3
As preferably, the diameter of described inner core is 6-8mm.
As preferably, described intermediate passivation layer is the oxalic acid passive film, and described outer layer pipe is the 08A welded tube.
As preferably, described welded tube diameter is 8-12mm, and thickness is 0.5-1.0mm.
Make the method for above-mentioned solid metal Mg alloy cored wine for steel desulfurization, may further comprise the steps: solid metal magnesium alloy wire and steel band are sent into the argon arc welding unit simultaneously, and through compression, welding and drawing formation inner core, steel band is made weldless steel tube wrap up described inner core as skin.
As preferably, described argon arc welding unit comprises the gatherer for location and importing steel band and solid metal magnesium alloy wire, be used for curling steel band and be tubulose format roll, be used for preventing the magnesium alloy wire vibration hold-down head, be used for the welding rolls of welding steel band and be used for adjusting the tube reducing roller of cored-wire diameter, described gatherer, format roll, hold-down head, welding rolls and tube reducing roller are linked in sequence successively.
The present invention is owing to having adopted technique scheme, 1. the solid metal Mg alloy cored wine is that outer layer pipe, intermediate passivation layer, inner core are the special construction of solid metal magnesium alloy wire, so that the hot strength of cored-wire improves greatly, greatly improved the penetrativity of cored-wire, so that magnesium can join the molten steel deep veritably, utilize the static pressure of molten steel, make MAGNESIUM METAL before becoming magnesium steam namely with molten steel in the reaction such as sulphur, oxygen, greatly improved the recovery rate of MAGNESIUM METAL;
2. inner core is solid construction in the solid metal Mg alloy cored wine, compare with the spray magnesium granules, because the specific surface area of magnesium alloy wire is dwindled greatly, therefore reduced the gasification rate of MAGNESIUM METAL, increase the time that MAGNESIUM METAL is absorbed by molten steel, and can obtain the higher rate of recovery and stable at molten steel.
Use this kind product can obtain following positively effect:
1) magnesium treating processes recovery rate improves by a relatively large margin, and stable, greatly reduces the magnesium processing cost;
2) shorten the magnesium treatment time, reduced temperature losses of the process;
3) avoid bringing into of harmful element in the magnesium powder.
Description of drawings
Fig. 1 is the structure iron that is used for the solid metal Mg alloy cored wine of steel desulfurization;
1 is the magnesium alloy inner core among the figure, and 2 is the oxalic acid passivation layer, and 3 is outer layer pipe;
Fig. 2 is the structural representation of argon arc welding unit;
1 is inner core among the figure, and 2 is the oxalic acid passivation layer, and 3 is outer, and 4 is gatherer, and 5 is format roll, and 6 is hold-down head, and 7 is welding rolls, and 8 is the tube reducing roller, and 9 is magnesium alloy wire, and 10 is steel band.
Embodiment
Below in conjunction with accompanying drawing the specific embodiment of the present invention is further described.
Figure 1 shows that the present invention is used for the solid metal Mg alloy cored wine of steel desulfurization, comprise outer layer pipe, intermediate passivation layer and inner core, described inner core is the solid metal magnesium alloy wire of impurity weight summation≤0.2wt%.The composition of described solid metal magnesium alloy wire comprises: magnesium 93.6wt%, aluminium 3wt%, calcium 3wt%, rare earth 0.2wt%, 0.2wt% impurity, alloy density are 1.73g/cm
3Described intermediate passivation layer is the oxalic acid passive film, and described outer layer pipe is the 08A welded tube.Described welded tube diameter is 8-12mm, and thickness is 0.5-1.0mm.
The diameter of described inner core is 6-8mm; Its manufacturing process is: magnesium alloy batching melting-thermal treatment-heating-extruding-oxalic acid passivation-batch.
Make the method for above-mentioned solid metal Mg alloy cored wine for steel desulfurization, magnesium alloy wire and the steel band of oxalic acid passivation are sent into the argon arc welding unit simultaneously, and obtain solid seamless Mg alloy cored wine through compression, welding and drawing.Wherein said steel band is 08A steel band or 08D steel band or carbon steel steel band, and the thickness of steel band is 0.5-1.0mm.
As shown in Figure 2, described argon arc welding unit comprises the gatherer for location and importing steel band and magnesium alloy wire, be used for curling steel band and be tubulose format roll, be used for preventing the magnesium alloy wire vibration hold-down head, be used for the welding rolls of welding steel band and be used for adjusting the tube reducing roller of cored-wire diameter, described gatherer, format roll, hold-down head, welding rolls and tube reducing roller are linked in sequence successively.
Mg alloy cored wine for steel desulfurization of the present invention is by outer 3 parcel middle layers 2, and middle layer 2 parcel inner cores 1 form.The specifications parameter of Mg alloy cored wine is as follows:
Cored-wire diameter: 8-12mm
The chemical composition of magnesium alloy wire (quality %):
Process the feeding in latter stage at iron ladle,
(1) steel grade: (ML35), enter stove sulphur＜＜0.010%, finished product 0.012% uses cored-wire molten iron 0.35kg/ per ton ton, saves 0.16Kg than spray magnesium powder.
(2) steel grade: (82B), enter stove sulphur＜＜0.05%, finished product 0.006% uses cored-wire molten iron 0.30kg/ per ton ton, saves 0.2Kg than spray magnesium powder.
The recovery rate of magnesium is more stable after the line feeding, average recovery rate is (60) %, average whole desulfurization is 0.008%, the molten iron cast is normal after the line feeding, show that solid metal Mg alloy cored wine of the present invention can also promote inclusion modification, purify hot metal and improve the pouring molten steel performance, and can remove the magnesium powder and in transport pipe, accumulate and stifled rifle.
Mg alloy cored wine of the present invention can be used for the desulfurization of molten iron or molten steel, and it is comprised of outer layer pipe, intermediate passivation layer and solid magnesium alloy wire.When the solid metal Mg alloy cored wine when being used for molten iron or molten steel wire feeding process, compare with existing spray magnesium powder technology, can effectively increase magnesium alloy solid cored-wires depth of penetration, owing to being solid, reduce the surface-area that magnesium contacts with molten iron, add the passive film that adds, greatly reduced the vapour pressure of magnesium, reduced the boiling of molten iron or molten steel, increase the quantity that magnesium and sulphur participate in reaction, thereby reduced the loss of magnesium, improved the sweetening effectiveness of magnesium, increased the rate of the receipts of magnesium, and then the cost that has reduced in original spray magnesium powder process drops into.
The scaling loss that can reduce MAGNESIUM METAL for the solid metal Mg alloy cored wine of steel desulfurization provided by the invention, relatively improve the magnesium gasification rate, increase the depth of penetration of cored-wire and the time that MAGNESIUM METAL is absorbed by molten steel, overcome pulvis magnesium cored-wire depth of penetration excessively low, unit volume magnesium and molten steel fraction reacted reduce and the shortcoming such as splash in molten steel, and avoided detrimental impurity element in the pulvis cored-wire, prolonged the refining time of magnesium in molten steel, improved Mg utilization, the magnesium that has solved as refining agent adds this difficult problem of mode to molten steel, thereby has improved greatly the recovery rate of MAGNESIUM METAL.
Claims (6)
1. solid metal Mg alloy cored wine that is used for steel desulfurization, it is characterized in that: comprise outer layer pipe, intermediate passivation layer and inner core, described inner core is the solid metal magnesium alloy wire of impurity weight summation≤0.2wt%, the composition of described solid metal magnesium alloy wire comprises: magnesium 92-98wt%, aluminium 0.5-3wt%, calcium 0.5-3wt%, rare earth 0.1-0.9wt%, alloy density are 1.73g/cm
3
2. described solid metal Mg alloy cored wine for steel desulfurization according to claim 1 and 2, it is characterized in that: the diameter of described inner core is 6-8mm.
3. described solid metal Mg alloy cored wine for steel desulfurization according to claim 1, it is characterized in that: described intermediate passivation layer is the oxalic acid passive film, described outer layer pipe is the 08A welded tube.
4. described solid metal Mg alloy cored wine for steel desulfurization according to claim 3, it is characterized in that: described welded tube diameter is 8-12mm, thickness is 0.5-1.0mm.
5. make the method for the described solid metal Mg alloy cored wine for steel desulfurization of claim 1, it is characterized in that: may further comprise the steps: solid metal magnesium alloy wire and steel band are sent into the argon arc welding unit simultaneously, and through compression, welding and drawing formation inner core, steel band is made weldless steel tube wrap up described inner core as skin.
6. described making is used for the method for the solid metal Mg alloy cored wine of steel desulfurization according to claim 5, it is characterized in that: described argon arc welding unit comprises the gatherer for location and importing steel band and solid metal magnesium alloy wire, be used for curling steel band and be tubulose format roll, be used for preventing the magnesium alloy wire vibration hold-down head, be used for the welding rolls of welding steel band and be used for adjusting the tube reducing roller of cored-wire diameter, described gatherer, format roll, hold-down head, welding rolls and tube reducing roller are linked in sequence successively.
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN104131136A (en) * | 2014-08-19 | 2014-11-05 | 马鞍山中科冶金材料科技有限公司 | Material for desulfurizing molten iron and molten steel and preparation method thereof |
| CN106521084A (en) * | 2016-11-18 | 2017-03-22 | 浙江宝信新型炉料科技发展有限公司 | Rare earth magnesium alloy cored wire containing multiple elements |
| CN106521085A (en) * | 2016-11-18 | 2017-03-22 | 浙江宝信新型炉料科技发展有限公司 | Multi-element rare earth magnesium alloy powder of cored wire |
| CN106702081A (en) * | 2016-11-18 | 2017-05-24 | 浙江宝信新型炉料科技发展有限公司 | High-magnesium rare earth magnesium alloy powder core spun yarn containing multiple elements |
| CN109055660A (en) * | 2018-08-31 | 2018-12-21 | 南京浦江合金材料股份有限公司 | A kind of core-spun yarn process units that can be precisely controlled core material ingredient and its control method |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN104131136A (en) * | 2014-08-19 | 2014-11-05 | 马鞍山中科冶金材料科技有限公司 | Material for desulfurizing molten iron and molten steel and preparation method thereof |
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| CN106521084A (en) * | 2016-11-18 | 2017-03-22 | 浙江宝信新型炉料科技发展有限公司 | Rare earth magnesium alloy cored wire containing multiple elements |
| CN106521085A (en) * | 2016-11-18 | 2017-03-22 | 浙江宝信新型炉料科技发展有限公司 | Multi-element rare earth magnesium alloy powder of cored wire |
| CN106702081A (en) * | 2016-11-18 | 2017-05-24 | 浙江宝信新型炉料科技发展有限公司 | High-magnesium rare earth magnesium alloy powder core spun yarn containing multiple elements |
| CN109055660A (en) * | 2018-08-31 | 2018-12-21 | 南京浦江合金材料股份有限公司 | A kind of core-spun yarn process units that can be precisely controlled core material ingredient and its control method |
| CN109055660B (en) * | 2018-08-31 | 2024-02-27 | 南京浦江合金材料股份有限公司 | Cored wire production device capable of accurately controlling core material components and control method thereof |
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