CN101845582B - Production method of high magnetic induction oriented silicon steel - Google Patents
Production method of high magnetic induction oriented silicon steel Download PDFInfo
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- CN101845582B CN101845582B CN2009100482893A CN200910048289A CN101845582B CN 101845582 B CN101845582 B CN 101845582B CN 2009100482893 A CN2009100482893 A CN 2009100482893A CN 200910048289 A CN200910048289 A CN 200910048289A CN 101845582 B CN101845582 B CN 101845582B
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Abstract
The invention relates to a production method of high magnetic induction oriented silicon steel, comprising the steps of smelting, continuous casting, hot rolling, normalization, decarbonization and annealing, MgO coating, high-temperature annealing and insulation coating, wherein the normalization comprises the steps that: normalization is carried out on a hot rolling plate, nitridation is finished synchronously, the temperature of normalization and nitridation is 1050-1150 DEG C, the atmosphere is 5-35% NH3 (volume percentage), and the balance of gas is N2; after the normalization and nitridation, the N content nitrided into the hot rolling plate is 60-250ppm; and normalization cooling is carried out, the initial temperature of fast cooling is 700-950 DEG C, and the fast cooling speed with the temperature of being reduced to 550 DEG C is 15-40 DEG C/s. The production method solves the problem of difficult nitridation in the decarbonization procedure when a low-temperature plate blank heating technology is used for producing the high magnetic induction oriented silicon steel, carries out synchronous nitridation on the hot rolling plate in the normalization procedure, and leads the following procedure of decarbonization and annealing techniques to be simplified and easily controlled, thus not only being capable of obtaining a high magnetic induction oriented silicon steel product with excellent performance and simultaneously leading the production cost to be reduced.
Description
Technical field
The present invention relates to a kind of a kind of high magnetic induction grain-oriented silicon steel cheaply of production method production method of high magnetic induction oriented silicon steel; be characterized in heating the hot rolled coil that (1100～1250 ℃) technology obtains at the low temperature slab; by in the normalizing operation it being carried out synchronous nitriding, the decarburizing annealing technology of so just feasible back operation is simplified and is easy to be controlled.In the high magnetic induction oriented silicon steel that obtains the magnetic property excellence, production cost is reduced greatly.
Background technology
The production method of tradition high magnetic induction grain-oriented silicon steel is as follows:
Make steel with converter (or electric furnace), carry out secondary refining and alloying, continuous casting becomes slab, its basic chemical ingredients is Si (2.5～4.5%), C (0.06～0.10%), Mn (0.03～0.1%), S (0.012～0.050%), Als (0.02～0.05%), N (0.003～0.012%), the composition system that has also contains one or more in the elements such as Cu, Mo, Sb, B, Bi, and all the other are iron and unavoidable impurities element; The temperature of slab more than special-purpose high temperature process furnace internal heating to 1350 ℃, and carry out the above insulation of 45min, make favourable inclusion MnS or the abundant solid solution of AlN, be rolled then, finishing temperature reaches more than 950 ℃, sprays water fast to be cooled to batch then below the 500C.So that in normalizing process subsequently, in the silicon steel matrix, separate out second phase particle, the i.e. inhibitor tiny, disperse; After the hot-rolled sheet normalizing, carry out pickling, remove scale on surface; Cold rolling sample is rolled finished product thickness, carry out decarburizing annealing and coating is the annealing separating agent of main component with MgO, [C] in the steel plate taken off the degree that do not influence finished product magnetic (generally should below 30ppm); In the high-temperature annealing process, steel plate generation secondary recrystallization, Magnesium Silicate q-agent bottom form and purify physicochemical change such as (remove in the steel S, N etc. to the deleterious element of magnetic), obtain orientation degree height, high magnetic induction grain-oriented silicon steel that iron loss is low; At last, through the coating insulating coating and the annealing that stretches, obtain the oriented silicon steel of commercial applications form.
Its deficiency is that the highest need of Heating temperature reach 1400 ℃ in order to make the abundant solid solution of inhibitor, and this is the Limiting Level of traditional heating stove.In addition, because the Heating temperature height, scaling loss is big, process furnace needs frequent the repairing, and utilization ratio is low.Simultaneously, the energy consumption height, the limit of hot rolled coil is split greatly, causes cold rolling process to produce difficulty, and lumber recovery is low, and cost is also high.
Just in view of above-mentioned these problems, research staff both domestic and external has carried out the research of a large amount of reduction oriented silicon steel Heating temperatures, its main improved trend has been distinguished two kinds according to the Heating temperature scope, a kind of be slab heating temperature at 1250～1320 ℃, adopt the inhibitor of AlN and Cu; Another kind be slab heating temperature at 1100～1250 ℃, the method that mainly adopts nitriding after the decarburization to form inhibitor obtains the inhibition ability.
Present stage low temperature slab heating technique development is very fast, for example United States Patent (USP) [US 5049205] and Japanese Patent [spy opens flat 5-112827] adopt and are carrying out the slab heating below 1200 ℃, the big cold rolling draft of final cold rolling employing 80%, and after decarburizing annealing, adopt ammonia to carry out continuous nitriding and handle, obtain the higher secondary recrystallization crystal grain of orientation degree.But this method is because the method that nitriding forms inhibitor after adopting the substrate decarburization obtains the inhibition ability, be difficult in working control overcome that the belt steel surface oxidation is serious, nitriding is difficult and a difficult problem such as inhomogeneous, therefore cause acquisition type inhibitor in steel plate, to form difficulty, skewness, thereby influence the homogeneity of inhibition ability and secondary recrystallization, cause that the finished product magnetic property is inhomogeneous.
Chinese patent CN1978707 has described the novel process of carrying out decarburizing annealing after the first nitriding for the cold-reduced sheet that is rolled down to finished product thickness, but needs strict control dew point in nitriding process, can introduce the new problem of decarburization difficulty simultaneously again.
The method that Korean Patent KR2002074312 propose to adopt decarburization and nitriding to carry out synchronously though this can solve the problem of back decarburization difficulty or back nitriding difficulty, but still can't avoid causing because of nitriding is inhomogeneous problem such as the inhomogeneous and cost costliness of product magnetic property.
Summary of the invention
The object of the present invention is to provide a kind of production method of high magnetic induction oriented silicon steel, the problem of nitriding difficulty in the decarbonization process when solving low temperature slab heating technique production high magnetic induction grain-oriented silicon steel.By in the normalizing operation hot-rolled sheet being carried out synchronous nitriding, the decarburizing annealing technology of so just feasible back operation is simplified and is easy to be controlled.This can obtain the high magnetic induction oriented silicon steel of magnetic property excellence, simultaneously production cost is reduced.
Technical scheme of the present invention is,
A kind of production method of high magnetic induction grain-oriented silicon steel, it comprises smelting, continuous casting, hot rolling, normalizing, cold rolling, decarburizing annealing, MgO coating, high temperature annealing and insulating coating; Wherein,
Described normalizing comprises that hot-rolled sheet when carrying out normalizing, finishes nitriding, 1050～1150 ℃ of normalizing nitriding temperatures, time 50～100s, 15～75 ℃ of dew points, atmosphere 5～35%NH synchronously
3(volume percent), remaining gas are N
2[N] content 60～250ppm that infiltrates in the hot-rolled sheet after the normalizing nitriding;
[N] content and the nitriding parameters such as hot-rolled sheet thickness, nitriding temperature, nitriding time and ammonia ratio of infiltrating meet following relationship:
[N] content that infiltrates=-3.08a
2+ 0.04b+0.96c+4.12d+C
Wherein, a: hot-rolled sheet thickness (mm); B: nitriding temperature (℃); C: nitriding time (s); D: ammonia ratio (%); C: constant;
After the normalizing nitriding, realize that by technology for controlled cooling the AlN particulate volume fraction of size≤300nm accounts for more than 60% of AlN cumulative volume; 700～950 ℃ of starting temperatures are cooled off in the normalizing cooling fast, are cooled to 550 ℃ 15～40 ℃/sec of quick speed of cooling.
Further, described silicon steel chemical component weight per-cent is: C:0.055～0.120%, Si:2.9～4.0%, Mn:0.05～0.20%, S:0.005～0.010%, Als:0.015～0.035%, N:0.001～0.009%, Sn:0.005～0.070%, all the other are Fe and inevitable inclusion.
Described hot rolling be slab in process furnace internal heating to 1100～1250 ℃, soaking time 20～120 minutes, 1050～1090 ℃ of start rolling temperatures, finishing temperature is 930～950 ℃, roll into the hot-rolled sheet of 2.0～3.0mm thickness, roll back laminar flow cooling, 600 ℃ are batched below the temperature.
Described cold rolling be after normalizing, use the once cold rolling method that the normalizing plate is rolled down to production board thickness.
Described decarburizing annealing is 15～35 ℃/sec of heat-up rate, 800～860 ℃ of decarburization temperature, insulation 90～160sec.
Described MgO coating and high temperature annealing: the steel plate to above-mentioned decarburizing annealing carries out the MgO coating and carry out high temperature annealing in bell furnace, 1200 ℃～1250 ℃ of annealing temperatures.
Described insulating coating is: at high temperature annealing plate surface applied insulating coating, and obtain the high magnetic induction grain-oriented silicon steel of excellent magnetic through the smooth annealing of thermal stretch.
Beneficial effect of the present invention
Normalizing of the present invention is different from the existing Technology nitriding and finishes at the later stage decarbonization process, and hot-rolled sheet of the present invention is when carrying out normalizing, finishes nitriding synchronously.
The present invention has increased the content of C, γ when C can make hot rolling-increase mutually, and the hot-rolled sheet structure refinement is the thin deformation crystal grain and the little recrystal grain of layered distribution also, first crystal grain is tiny evenly.In addition, the C height also can improve hot rolling and cold rolling processibility, prevents that hot-rolled sheet from producing transverse fissure; Smelting operation is easy, and FeO content reduces in the slag, improves the steel rate of recovery and lining life, and then also plays the effect that reduces production costs.
Reduce the content of S in the steel, stop the formation of MnS.In addition, carry out nitriding when considering normalizing in the present invention, therefore can reduce the content of N in the steel, thereby improve the continuous casting steel billet quality.
Als content is the most obvious to the influence of magnetic.The Als too high levels, slab heating temperature improves, and makes the bottom layer quality variation easily; Als content is low excessively, and restraining effect weakens.
The steel-making composition also adds the Sn of appropriate amount among the present invention, and this can make the surface form the Sn enriched layer, prevents the denitrogenation or absorb excessive nitrogen prematurely in the high temperature annealing temperature-rise period of steel plate after nitriding is handled.In addition, solid solution fully when the slab reheat is also strengthened restraint along crystal boundary is poly-partially later on, makes first grain-size more tiny evenly, guarantees that secondary recrystallization is perfect.
Hot-rolled sheet has been finished nitriding among the present invention in normalizing, and making has just had [N] content that satisfies low-temperature oriented silicon steel requirement after the normalizing in the plate.[N] that infiltrate in the plate can just form part A lN inhibitor with Als in normalizing; and the inhibitor of under suitable normalizing temperature and cooling conditions, separating out ideal dimensions, form and distribution situation, thereby the high magnetic induction oriented silicon steel that can obtain having excellent magnetic characteristics.
Hot-rolled sheet has been finished nitriding among the present invention in normalizing, and making has just had [N] content that satisfies low-temperature oriented silicon steel requirement after the normalizing in the plate.So just can when cold-reduced sheet decarburizing annealing, save the nitriding operation, simplify processing requirement.
Though hot-rolled sheet is thicker than cold-reduced sheet, the time of infiltrating identical [N] content on the unit length will be about 2～3 times; But, consider that hot-rolled sheet plate length direction after cold rolling will extend 8～10 times.Therefore, the coil of strip of unit weight is in the nitriding total time that will be longer than far away spent total time of nitriding under the cold-reduced sheet state under the hot-rolled sheet state.For this reason, nitriding simultaneously will greatly be enhanced productivity in the normalizing process, also can save the consumption of ammonia greatly.
Because the more cold rolling thickness of slab of hot-rolled sheet, this need spend the more time just can make the nitriding amount satisfy the requirement of low-temperature oriented silicon steel.But the nitriding time of these prolongations just; can so that distribute in the hot-rolled sheet of [N] content after normalizing more even; and such nitriding homogeneity can be genetic to cold-reduced sheet and decarburization plate fully; and then the AlN inhibitor even dispersion that forms in the plate when making high temperature annealing, also more trend is stable for the magnetic property of the finished product.
Suitable decarburization temperature can guarantee that Gauss's nucleus primary recrystallization is good, also lays the first stone for the good magnetic property of final finished.
Embodiment
Embodiment 1
Smelt and casting according to the described chemical ingredients of table 1.The slab of heterogeneity is placed in 1175 ℃ of process furnace is hot-rolled down to the hot-rolled sheet that thickness is 2.5mm behind the insulation 90min, open rolling and finishing temperature are respectively 1082 ℃ and 947 ℃.Adopt normalizing and nitriding to carry out synchronously to hot-rolled sheet, and select suitable normalizing nitridation process: 1115 ℃ of normalizing nitriding temperatures---time 75s---40 ℃ of dew points---NH
3---cooling starting temperature 820 ℃---23 ℃/s of speed of cooling---is infiltrated [N] content 172ppm to ratio 25%.And after pickling, be cold rolled to finished product thickness 0.30mm thickness.Under the condition of 26 ℃/s of temperature rise rate, 815 ℃ of decarburization temperature, samming 150s, carry out decarburizing annealing, make that [C] content drops to below the 30ppm in the steel plate.After coating MgO is the separant of main component, be 100%H in atmosphere
2, dew point is-10 ℃, temperature is the high temperature annealing that carried out under 1200 ℃ the condition 20 hours.Coated insulating coating and stretching and leveling annealing after the uncoiling, the finished product magnetic property that obtains sees Table 1.
Table 1 chemical ingredients is to the influence of magnetic property
| Embodiment | C (％) | Si (％) | Mn (％) | S (％) | Als (％) | N (％) | Sn (％) | B 8 (T) | P 17/50 (W/kg) |
| 1 | 0.055 | 4.0 | 0.10 | 0.010 | 0.015 | 0.009 | 0.045 | 1.92 | 0.97 |
| 2 | 0.120 | 3.2 | 0.20 | 0.005 | 0.025 | 0.005 | 0.070 | 1.92 | 0.99 |
| 3 | 0.065 | 2.9 | 0.05 | 0.008 | 0.035 | 0.001 | 0.005 | 1.93 | 0.97 |
| 4 | 0.090 | 3.6 | 0.14 | 0.006 | 0.019 | 0.003 | 0.026 | 1.94 | 0.95 |
| 5 | 0.113 | 3.8 | 0.07 | 0.009 | 0.031 | 0.007 | 0.013 | 1.93 | 0.97 |
| 6 | 0.077 | 3.4 | 0.18 | 0.005 | 0.023 | 0.007 | 0.058 | 1.93 | 0.96 |
| Comparative Examples 1 | 0.052 | 4.2 | 0.15 | 0.006 | 0.013 | 0.010 | 0.035 | 1.87 | 1.08 |
| 2 | 0.070 | 2.7 | 0.04 | 0.004 | 0.037 | 0.008 | 0.072 | 1.87 | 1.11 |
| 3 | 0.124 | 3.5 | 0.22 | 0.011 | 0.029 | 0.0005 | 0.004 | 1.86 | 1.12 |
| 4 | 0.081 | 4.1 | 0.12 | 0.007 | 0.010 | 0.0002 | 0.024 | 1.85 | 1.14 |
Since the present invention that adopt with existing oriented silicon steel all different " normalizing-nitriding " synchronous process of producing, therefore need be by testing to determine best chemical ingredients.
Can see that from table 1 result to satisfy finished product magnetic property of the present invention generally fine when chemical ingredients, the magnetic property of embodiment 1～6 is generally fine, can both reach high magnetic induction grain-oriented silicon steel level in kind (B8 〉=1.90T).Otherwise when chemical ingredients and technical scheme of the present invention were not inconsistent, the magnetic property of Comparative Examples 1～4 was all a bit weaker, can only reach the level (B8 〉=1.85T) of common orientation silicon steel material object reluctantly.
Embodiment 2
The component of directional silicon steel slab and weight percent are Si:3.25%, C:0.070%, and S:0.009%, Als:0.033%, N:0.05%, Mn:0.15%, Sn:0.008%, all the other are Fe and unavoidable impurities.
Different hot rolling technology conditions is as shown in table 2 below.Adopt normalizing and nitriding to carry out synchronously to the 2.3mm hot-rolled sheet, and select suitable normalizing nitridation process: 1085 ℃ of normalizing nitriding temperatures---time 65s---30 ℃ of dew points---NH
3---cooling starting temperature 780 ℃---33 ℃/s of speed of cooling---is infiltrated [N] content 145ppm to ratio 20%.And after pickling, be cold rolled to finished product thickness 0.30mm thickness.Under the condition of 29 ℃/s of temperature rise rate, 855 ℃ of decarburization temperature, samming 120s, carry out decarburizing annealing, make that [C] content drops to below the 30ppm in the steel plate.After coating MgO is the separant of main component, be 100%H in atmosphere
2, dew point is-10 ℃, temperature is the high temperature annealing that carried out under 1200 ℃ the condition 20 hours.Coated insulating coating and stretching and leveling annealing after the uncoiling, the finished product magnetic property that obtains sees Table 2.
Table 2 hot rolling technology condition is to the influence of magnetic property
| Sequence number | The slab heating cycle | Start rolling temperature (℃) | Finishing temperature (℃) | Curling temperature (℃) | B8 (T) | P17/50 (w/kg) |
| Embodiment 1 | 1100℃×120min | 1060 | 945 | 576 | 1.92 | 0.99 |
| 2 | 1250℃×20min | 1070 | 936 | 588 | 1.92 | 1.00 |
| 3 | 1150℃×50min | 1085 | 940 | 564 | 1.93 | 0.96 |
| 4 | 1130℃×100min | 1050 | 950 | 550 | 1.92 | 0.98 |
| 5 | 1210℃×30min | 1065 | 930 | 591 | 1.91 | 0.99 |
| 6 | 1190℃×85min | 1055 | 935 | 600 | 1.93 | 0.96 |
| Comparative Examples 1 | 1090℃×30min | 1090 | 933 | 577 | 1.86 | 1.11 |
| 2 | 1255℃×50min | 1054 | 954 | 589 | 1.84 | 1.18 |
| 3 | 1140℃×15min | 1072 | 936 | 582 | 1.84 | 1.16 |
| 4 | 1160℃×130min | 1081 | 941 | 580 | 1.86 | 1.12 |
| 5 | 1135℃×45min | 1041 | 941 | 584 | 1.87 | 1.10 |
| 6 | 1125℃×65min | 1098 | 932 | 590 | 1.87 | 1.09 |
| 7 | 1215℃×55min | 1052 | 923 | 592 | 1.88 | 1.06 |
| 8 | 1170℃×80min | 1086 | 957 | 568 | 1.86 | 1.11 |
| 9 | 1195℃×60min | 1066 | 939 | 616 | 1.86 | 1.09 |
Since technical solution of the present invention that adopt with existing oriented silicon steel all different " normalizing-nitriding " synchronous process of producing, therefore need be by testing to determine best hot rolling technology scheme.Can see from table 2 result, when hot rolling technology satisfies technical scheme of the present invention---slab is in process furnace internal heating to 1100～1250 ℃, soaking time 20～120 minutes, 1050～1090 ℃ of start rolling temperatures, finishing temperature is 930～950 ℃, rolls into the hot-rolled sheet of 2.0～3.0mm thickness, roll back laminar flow cooling, 600 ℃ when batching below the temperature, the magnetic property of embodiment 1～6 is generally fine, can both reach high magnetic induction grain-oriented silicon steel level in kind (B8 〉=1.90T).Otherwise when hot rolling technology and technical scheme of the present invention were not inconsistent, the magnetic property of Comparative Examples 1～9 was all a bit weaker, can only reach the level (B8 〉=1.85T) of common orientation silicon steel material object reluctantly.
Embodiment 3
The component of directional silicon steel slab and weight percent are Si:3.25%, C:0.070%, and S:0.009%, Als:0.033%, N:0.05%, Mn:0.15%, Sn:0.008%, all the other are Fe and unavoidable impurities.Be hot-rolled down to the hot-rolled sheet that thickness is 2.3mm it is incubated 30min in 1190 ℃ of process furnace after, open rolling and finishing temperature are respectively 1080 ℃ and 942 ℃.Different normalizing and nitridation process condition are as shown in table 3 below.And after pickling, be cold rolled to finished product thickness 0.30mm thickness.Under the condition of 28 ℃/s of temperature rise rate, 855 ℃ of decarburization temperature, samming 140s, carry out decarburizing annealing, make that [C] content drops to below the 30ppm in the steel plate.After coating MgO is the separant of main component, be 100%H in atmosphere
2, dew point is-10 ℃, temperature is the high temperature annealing that carried out under 1200 ℃ the condition 20 hours.Coated insulating coating and stretching and leveling annealing after the uncoiling, the finished product magnetic property and the AlN volume fraction that obtain see Table 3.
Because the technology that in existing production oriented silicon steel production technology, does not also have " normalizing-nitriding " to carry out synchronously.Therefore, the present invention need determine best process program by " normalizing-nitriding " test of table 3.Can see from the test-results of table 3, when " normalizing-nitriding " technology satisfies technical scheme of the present invention---nitriding is finished in normalizing simultaneously, 1050～1150 ℃ of normalizing nitriding temperatures, time 50～100s, 15～75 ℃ of dew points, atmosphere 5～35%NH
3(volume percent), remaining gas are N
2[N] content 60～250ppm that infiltrates in the hot-rolled sheet after the normalizing nitriding.700～950 ℃ of normalizing cooling starting temperatures, when being cooled to 550 ℃ 15～40 ℃/sec of quick speed of cooling, (magnetic property of 1#～10#) is generally fine, can both reach high magnetic induction grain-oriented silicon steel level in kind (B8 〉=1.90T) for embodiment.Otherwise when " normalizing-nitriding " technology and technical scheme of the present invention were not inconsistent, (magnetic property of 11#～25#) was all a bit weaker, can only reach the level (B8 〉=1.85T) of common orientation silicon steel material object for Comparative Examples.
Listed [N] content all is the actual numerical value that records after the hot-rolled sheet regular practice nitriding in the table 4.Now the nitriding parameter in the table 3 is utilized " [N] content of infiltration=-3.08a
2+ 0.04b+0.96c+4.12d+C " formula comes theory of computation nitriding value, and constant C gets 23.51.Table 4 is difference between the two.
Table 4[N] difference of content formula calculated value and actual value
| The normalizing nitriding temperature (℃) | Normalizing nitriding time (sec) | Normalizing nitriding atmosphere (NH 3％) | Actual [N] content (ppm) that infiltrates | Theoretical Calculation [N] content (ppm) | Difference (ppm) |
| 1050 | ?50 | ?25 | ?158 | 153.2 | -4.8 |
| 1060 | ?100 | ?15 | ?157 | 160.4 | 3.4 |
| 1075 | ?55 | ?20 | ?134 | 138.4 | 4.4 |
| 1095 | ?75 | ?35 | ?224 | 220.2 | -3.8 |
| 1100 | ?60 | ?30 | ?186 | 185.4 | -0.6 |
| 1110 | ?65 | ?5 | ?81 | 87.6 | 6.6 |
| 1120 | ?55 | ?10 | ?103 | 99.0 | -4.0 |
| 1125 | ?95 | ?20 | ?172 | 178.8 | 6.8 |
| 1135 | ?50 | ?30 | ?180 | 177.2 | -2.8 |
| 1150 | ?80 | ?5 | ?97 | 103.6 | 6.6 |
| 1120 | ?65 | ?15 | ?131 | 129.2 | -1.8 |
| 1040 | ?75 | ?25 | ?175 | 176.8 | 1.8 |
| 1155 | ?55 | ?10 | ?93 | 100.4 | 7.4 |
| 1135 | ?45 | ?20 | ?135 | 131.2 | -3.8 |
| 1085 | ?105 | ?5 | ?125 | 125.0 | 0 |
| 1100 | ?60 | ?30 | ?185 | 185.4 | 0.4 |
| 1090 | ?70 | ?10 | ?115 | 112.2 | -2.8 |
| 1060 | ?80 | ?3 | ?95 | 91.8 | -3.2 |
| 1115 | ?50 | ?40 | ?213 | 217.6 | 4.6 |
| 1075 | 75 | 35 | 216 | 219.4 | 3.4 |
| 1150 | 65 | 25 | 170 | 171.6 | 1.6 |
| 1050 | 60 | 15 | 124 | 121.6 | -2.4 |
| 1095 | 85 | 5 | 110 | 106.2 | -3.8 |
| 1050 | 50 | 5 | 58 | 70.8 | 12.8 |
| 1150 | 100 | 35 | 253 | 246.4 | -6.6 |
Can find that from the result of table 4 actual value of nitriding and the difference of calculated value are substantially all in 10ppm.Therefore can think that this formula carries out the normalizing nitriding to hot-rolled sheet and has better guide significance.
Embodiment 4
The component of directional silicon steel slab and weight percent are Si:3.25%, C:0.070%, and S:0.009%, Als:0.033%, N:0.05%, Mn:0.15%, Sn:0.008%, all the other are Fe and unavoidable impurities.Be hot-rolled down to the hot-rolled sheet that thickness is 2.3mm it is incubated 30min in 1190 ℃ of process furnace after, open rolling and finishing temperature are respectively 1080 ℃ and 942 ℃.Adopt normalizing and nitriding to carry out synchronously to hot-rolled sheet, and select suitable normalizing nitridation process: 1125 ℃ of normalizing nitriding temperatures---time 65s---60 ℃ of dew points---NH
3---cooling starting temperature 850 ℃---20 ℃/s of speed of cooling---is infiltrated [N] content 147ppm to ratio 20%.And after pickling, be cold rolled to finished product thickness 0.30mm thickness.Different decarburizing annealing processing condition are as shown in table 5 below.After the decarburizing annealing, make that [C] content drops to below the 30ppm in the steel plate.After coating MgO is the separant of main component, be 100%H in atmosphere
2, dew point is-10 ℃, temperature is the high temperature annealing that carried out under 1200 ℃ the condition 20 hours.Coated insulating coating and stretching and leveling annealing after the uncoiling, the finished product magnetic property that obtains sees Table 5.
The different decarburizing annealing technologies of table 5 are to the influence of finished product magnetic property
Because what technical solution of the present invention adopted is brand-new " normalizing-nitriding " synchronous process, therefore need be by testing to determine best decarburizing annealing process program.As can be seen from Table 5, when decarburizing annealing technology satisfies technical scheme of the present invention---15～35 ℃/sec of decarburization heat-up rate, 800～860 ℃ of decarburization temperature, during decarburizing annealing time 90～160sec, the magnetic property of embodiment 1～6 is generally fine, can both reach high magnetic induction grain-oriented silicon steel level in kind (B8 〉=1.90T).Otherwise when decarburizing annealing technology and technical scheme of the present invention were not inconsistent, the magnetic property of Comparative Examples 7～12 was all a bit weaker, can only reach the level (B8 〉=1.85T) of common orientation silicon steel material object.
The high magnetic induction grain-oriented silicon steel that low temperature slab heating technique is produced has advantages such as the process furnace life-span is long, and energy consumption and cost are low.But for a long time, because it is inhomogeneous and be difficult in process of production effectively adjust and problems such as control to exist back operation decarburization nitriding, thereby have influence on local or whole inhibition ability in the substrate, cause the secondary recrystallization imperfection, product magnetic property instability.
The present invention is based on a kind of new high magnetic induction grain-oriented silicon steel production method on the low temperature slab heating technique, and it has solved the problems referred to above effectively.Its characteristics are can successfully simplify decarbonization process under the composition system of present low-temperature oriented silicon steel, and enhance productivity by hot-rolled sheet is finished normalizing and nitriding synchronously.In addition, the inventive method compare with other method the finished product magnetic property is improved and stability on also tool have an enormous advantage.
Claims (7)
1. the production method of a high magnetic induction grain-oriented silicon steel, it comprises smelting, continuous casting, hot rolling, normalizing, cold rolling, decarburizing annealing, MgO coating, high temperature annealing and insulating coating, it is characterized in that,
Described normalizing comprises that hot-rolled sheet when carrying out normalizing, finishes nitriding, 1050～1150 ℃ of normalizing nitriding temperatures, time 50～100s, 15～75 ℃ of dew points, atmosphere 5～35%NH synchronously
3(volume percent), remaining gas are N
2[N] content 60～250ppm that infiltrates in the hot-rolled sheet after the normalizing nitriding;
[N] content and hot-rolled sheet thickness, nitriding temperature, nitriding time and the ammonia ratio of infiltrating meet following relationship:
[N] content that infiltrates=-3.08a
2+ 0.04b+0.96c+4.12d+C
Wherein, a: hot-rolled sheet thickness, unit: mm; B: nitriding temperature, unit: ℃; C: nitriding time, unit: s; D: ammonia ratio, unit: %; C: constant;
After the normalizing nitriding, realize that by technology for controlled cooling the AlN particulate volume fraction of size≤300nm accounts for more than 60% of AlN cumulative volume; 700～950 ℃ of starting temperatures are cooled off in the normalizing cooling fast, are cooled to 550 ℃ 15～40 ℃/sec of quick speed of cooling.
2. the production method of high magnetic induction grain-oriented silicon steel as claimed in claim 1, it is characterized in that, described silicon steel chemical component weight per-cent is: C:0.055～0.120%, Si:2.9～4.0%, Mn:0.05～0.20%, S:0.005～0.010%, Als:0.015～0.035%, N:0.001～0.009%, Sn:0.005～0.070%, all the other are Fe and inevitable inclusion.
3. the production method of high magnetic induction grain-oriented silicon steel as claimed in claim 1, it is characterized in that, described hot rolling is that slab is in process furnace internal heating to 1100～1250 ℃, soaking time 20～120 minutes, 1050～1090 ℃ of start rolling temperatures, finishing temperature is 930～950 ℃, rolls into the hot-rolled sheet of 2.0～3.0mm thickness, roll back laminar flow cooling, 600 ℃ are batched below the temperature.
4. the production method of high magnetic induction grain-oriented silicon steel as claimed in claim 1 is characterized in that, described cold rolling be after normalizing, use the once cold rolling method that the normalizing plate is rolled down to production board thickness.
5. the production method of high magnetic induction grain-oriented silicon steel as claimed in claim 1 is characterized in that, described decarburizing annealing is 15～35 ℃/sec of heat-up rate, 800～860 ℃ of decarburization temperature, insulation 90～160sec.
6. the production method of high magnetic induction grain-oriented silicon steel as claimed in claim 1, it is characterized in that, described MgO coating and high temperature annealing: the steel plate to above-mentioned decarburizing annealing carries out the MgO coating and carry out high temperature annealing in bell furnace, 1200 ℃～1250 ℃ of annealing temperatures.
7. the production method of high magnetic induction grain-oriented silicon steel as claimed in claim 1 is characterized in that, described insulating coating is: at high temperature annealing plate surface applied insulating coating, and obtain the high magnetic induction grain-oriented silicon steel of excellent magnetic through the smooth annealing of thermal stretch.
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| CN102443736B (en) * | 2010-09-30 | 2013-09-04 | 宝山钢铁股份有限公司 | Method for producing high magnetic flux-density oriented silicon steel product |
| CN102560236B (en) * | 2010-12-17 | 2013-07-31 | 鞍钢股份有限公司 | Preparation method of common oriented silicon steel |
| CN102758127B (en) * | 2011-04-28 | 2014-10-01 | 宝山钢铁股份有限公司 | Method for producing high magnetic induction orientation silicon steel with excellent magnetic performance and good bottom layer |
| CN103695619B (en) | 2012-09-27 | 2016-02-24 | 宝山钢铁股份有限公司 | A kind of manufacture method of high magnetic strength common orientation silicon steel |
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| CN103937941B (en) * | 2013-12-27 | 2016-01-20 | 上海实业振泰化工有限公司 | A kind of oriented silicon steel preparation method of extraordinary magnesium oxide boron additive material |
| CN106435134B (en) * | 2016-11-02 | 2018-07-06 | 浙江华赢特钢科技有限公司 | A kind of production technology of silicon steel sheet |
| CN106755874B (en) * | 2016-11-18 | 2018-06-26 | 武汉钢铁有限公司 | A kind of decarburization for producing low temperature high magnetic induction grain-oriented silicon steel and nitriding method for annealing |
| CN108723790B (en) * | 2018-06-08 | 2021-05-07 | 绍兴栢安管业科技有限公司 | Production line of circular pull rod |
| CN108907610B (en) * | 2018-06-08 | 2021-05-07 | 绍兴栢安管业科技有限公司 | Forming method of circular pull rod |
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1796587A (en) * | 2004-12-27 | 2006-07-05 | 宝山钢铁股份有限公司 | Orientating silicon steel, manufacturing process and equipment |
| CN1978707A (en) * | 2005-11-29 | 2007-06-13 | 宝山钢铁股份有限公司 | Method for producing oriented silicon steel with good bottom by low-temperature heating |
| CN101294268A (en) * | 2007-04-24 | 2008-10-29 | 宝山钢铁股份有限公司 | Nitrogen case hardening method of orientation silicon steel |
| CN101333619A (en) * | 2007-06-25 | 2008-12-31 | 宝山钢铁股份有限公司 | Technological process for controlling secondary recrystallization crystal particle dimension of oriented silicon steel |
-
2009
- 2009-03-26 CN CN2009100482893A patent/CN101845582B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1796587A (en) * | 2004-12-27 | 2006-07-05 | 宝山钢铁股份有限公司 | Orientating silicon steel, manufacturing process and equipment |
| CN1978707A (en) * | 2005-11-29 | 2007-06-13 | 宝山钢铁股份有限公司 | Method for producing oriented silicon steel with good bottom by low-temperature heating |
| CN101294268A (en) * | 2007-04-24 | 2008-10-29 | 宝山钢铁股份有限公司 | Nitrogen case hardening method of orientation silicon steel |
| CN101333619A (en) * | 2007-06-25 | 2008-12-31 | 宝山钢铁股份有限公司 | Technological process for controlling secondary recrystallization crystal particle dimension of oriented silicon steel |
Non-Patent Citations (1)
| Title |
|---|
| JP特开平6-212261A 1994.08.02 |
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