CN112553407A - 一种控氮核级特种钢的制备方法 - Google Patents
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- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 71
- 239000010959 steel Substances 0.000 title claims abstract description 71
- 229910052757 nitrogen Inorganic materials 0.000 title claims abstract description 18
- 238000002360 preparation method Methods 0.000 title claims abstract description 8
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 title abstract description 28
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims abstract description 80
- 229910052786 argon Inorganic materials 0.000 claims abstract description 40
- 238000007664 blowing Methods 0.000 claims abstract description 34
- 239000002893 slag Substances 0.000 claims abstract description 16
- 238000000034 method Methods 0.000 claims abstract description 15
- 229910052717 sulfur Inorganic materials 0.000 claims abstract description 15
- 238000006477 desulfuration reaction Methods 0.000 claims abstract description 12
- 230000023556 desulfurization Effects 0.000 claims abstract description 11
- 238000007670 refining Methods 0.000 claims abstract description 8
- 238000010079 rubber tapping Methods 0.000 claims abstract description 8
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 12
- 238000010438 heat treatment Methods 0.000 claims description 8
- 238000009847 ladle furnace Methods 0.000 claims description 8
- 238000007872 degassing Methods 0.000 claims description 7
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 6
- 238000005275 alloying Methods 0.000 claims description 6
- 238000005266 casting Methods 0.000 claims description 6
- 229910052742 iron Inorganic materials 0.000 claims description 6
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 4
- 229910052782 aluminium Inorganic materials 0.000 claims description 4
- 229910052799 carbon Inorganic materials 0.000 claims description 4
- 229910052760 oxygen Inorganic materials 0.000 claims description 4
- 229910052698 phosphorus Inorganic materials 0.000 claims description 4
- 235000008733 Citrus aurantifolia Nutrition 0.000 claims description 3
- 238000003723 Smelting Methods 0.000 claims description 3
- 235000011941 Tilia x europaea Nutrition 0.000 claims description 3
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 3
- WUKWITHWXAAZEY-UHFFFAOYSA-L calcium difluoride Chemical compound [F-].[F-].[Ca+2] WUKWITHWXAAZEY-UHFFFAOYSA-L 0.000 claims description 3
- 239000003795 chemical substances by application Substances 0.000 claims description 3
- 229910052681 coesite Inorganic materials 0.000 claims description 3
- 229910052593 corundum Inorganic materials 0.000 claims description 3
- 229910052906 cristobalite Inorganic materials 0.000 claims description 3
- 239000010436 fluorite Substances 0.000 claims description 3
- 239000004571 lime Substances 0.000 claims description 3
- 239000002994 raw material Substances 0.000 claims description 3
- 239000000377 silicon dioxide Substances 0.000 claims description 3
- 229910052682 stishovite Inorganic materials 0.000 claims description 3
- 229910052905 tridymite Inorganic materials 0.000 claims description 3
- 229910001845 yogo sapphire Inorganic materials 0.000 claims description 3
- 230000001502 supplementing effect Effects 0.000 claims description 2
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 abstract description 11
- 239000011593 sulfur Substances 0.000 abstract description 11
- 239000007788 liquid Substances 0.000 abstract description 7
- 238000004519 manufacturing process Methods 0.000 abstract description 6
- 238000010521 absorption reaction Methods 0.000 abstract description 3
- 239000000463 material Substances 0.000 abstract description 3
- 239000012752 auxiliary agent Substances 0.000 abstract description 2
- 230000002035 prolonged effect Effects 0.000 abstract description 2
- 230000003009 desulfurizing effect Effects 0.000 abstract 1
- 238000005096 rolling process Methods 0.000 description 4
- 238000009749 continuous casting Methods 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 238000009628 steelmaking Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000003749 cleanliness Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
Classifications
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/06—Deoxidising, e.g. killing
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/064—Dephosphorising; Desulfurising
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/10—Handling in a vacuum
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C33/00—Making ferrous alloys
- C22C33/04—Making ferrous alloys by melting
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/08—Ferrous alloys, e.g. steel alloys containing nickel
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/14—Ferrous alloys, e.g. steel alloys containing titanium or zirconium
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Abstract
本发明提供一种控氮核级特种钢的制备方法,通过在转炉出钢前添加造料渣,使出钢液表面形成脱硫渣,减少进入吹氩站钢液的硫含量以及钢液的裸露面,从而减少钢液吸氮量;进入吹氩站钢液的硫含量减少后,在同样的精炼时间内,可以提高氩气强吹时间,从而提高脱硫率。本发明制备的特种钢氮、硫含量低,性能高,不用添加额外的助剂以及更改复杂的工艺即可实现生产。
Description
技术领域
本发明属于制钢技术领域,特别涉及一种控氮核级特种钢的制备方法。
背景技术
随着窝工经济快速发展,基础建设大量增加,钢材用量也跟着极具增长。钢材在使用过程中不仅要承受静载荷,还要承受一定的动载荷,其中某些部位还好承受交变应力,在受力的状态下还要承受大气气候变化和腐蚀介质的考验,因此好的钢材必须具有较高的强度,还要有良好的塑形、韧性、可焊性以及较高的疲劳强度,而钢中硫、氮含量偏高会恶化钢材韧性、降低钢材塑形,导致钢材性能变差。目前钢材的连铸连轧技术,对钢液洁净度有较高要求,钢中氮、硫含量增加,导致连扎过程中钢坯表面出现质量缺陷,不仅恶化钢材性能,同时降低生产效率,增加生产成本。
为了适应低成本、高效率的精炼-连铸-连轧工艺发展及高性能钢的生产,迫切需要进一步优化钢包精炼的快速脱硫与氮控的工艺,进一步降低钢中硫、氮含量及其对连铸连轧的坯、材质量的影响。
发明内容
针对目前制钢工艺存在成本高,钢中氮、硫含量高的缺陷,本发明提供一种控氮核级特种钢的制备方法,改变脱硫精炼工艺,有效的降低钢材中的硫和氮的含量。
本发明是通过以下技术方案实现的:
一种控氮核级特种钢的制备方法,包括以下步骤:
(1)将原材料送至高炉进行熔炼,得到铁水;
(2)铁水送至转炉,脱氧合金化阶段加入钢芯铝,在脱氧合金化结束至出钢结束期间加入造料渣,得到含有以下质量分数组分的钢包:C 0.09%、Si 0.02%、Mn 0.06%,P0.014%,O 0.03%、N 0.045%;
(3)转炉结束后的钢包送至吹氩站,根据钢液成分进行补加精炼渣和脱氧剂,再送至LF炉进行脱硫35~40min,然后进行RH脱气,脱气后得到含有以下质量分数组分的钢液:C0.12%、Si 0.3%、Mn 1.5%,P ≤0.015%,S≤0.004%,Als 0.025,Nb 0.02%,Ti 0.013%,Ni0.2%,O 0.002%、N≤0.04%;
Als为钢液中的酸溶铝;
(4)出站后的钢液进行连铸,得到特种钢。
本发明在转炉出钢前加入造料渣,钢液表面会形成脱硫渣,从而减少进入吹氩站的钢中硫含量以及出钢期间钢液的裸露面,减少钢液吸氮;使得在固定的精炼时间内,需增加氩气强吹时间进行脱硫,提高脱硫量。最终出钢中氮、硫含量均有显著下降,从而提高钢的性能。
作为本发明的进一步改进,所述的脱硫工艺具体为首先氩气强吹2~4min,再氩气软吹3min,然后电极加热5~6min,通电结束后氩气强吹6min,再氩气软吹1min,再次电极加热6min,通电结束后氩气强吹4~6min,再氩气软吹8min即可。
作为本发明的进一步改进,所述的LF炉中,石灰用量为600~800kg/炉,萤石用量为60~80kg/炉。
作为本发明的进一步改进,所述的造料渣各组分的重量分数如下:CaO 55.20%,Al2O3 30%,SiO2 6.95%,MgO 8%。
本发明的有益效果:
1、本发明通过改变加入造料渣的时机,使转炉后的出钢液表面覆盖脱硫渣,减少钢液的裸露面,从而减少钢液吸氮;另一方面脱硫渣减少了进入吹氩站的钢中硫的含量,使得在精炼时间不变的情况下,可以提高氩气强吹时间,从而提高脱硫率。
2、本发明不用添加额外的助剂以及更改复杂的工艺即可实现生产,成本低,制备的成品钢力学性能强。
具体实施方式
下面结合实施例对本发明作进一步说明。
实施例1
一种控氮核级特种钢的制备方法,包括以下步骤:
(1)将原材料送至高炉进行熔炼,得到铁水;
(2)铁水送至转炉,脱氧合金化阶段加入钢芯铝,在脱氧合金化结束至出钢结束期间加入造料渣,得到含有以下质量分数组分的钢包:C 0.09%、Si 0.02%、Mn 0.06%,P0.014%,O 0.03%、N 0.045%;
(3)转炉结束后的钢包送至吹氩站,根据钢液成分进行补加精炼渣和脱氧剂,再送至LF炉,首先氩气强吹2min,再氩气软吹3min,然后电极加热5min,通电结束后氩气强吹6min,再氩气软吹1min,再次电极加热6min,通电结束后氩气强吹4min,再氩气软吹8min,完成脱硫,然后进行RH脱气,脱气后得到含有以下质量分数组分的钢液:C 0.12%、Si 0.3%、Mn1.5%,P 0.01%,S 0.0035%,Als 0.025,Nb 0.02%,Ti 0.013%,Ni 0.2%,O 0.002%、N 0.03%;
(4)出站后的钢液进行连铸,得到特种钢。
所述的LF炉中,石灰用量为600~800kg/炉,萤石用量为60~80kg/炉。
所述的造料渣各组分的重量分数如下:CaO 55.20%,Al2O3 30%,SiO2 6.95%,MgO8%。
实施例2
与实施例1相比较,本实施例的不同点在于:
所述的脱硫工艺具体为首先氩气强吹4min,再氩气软吹3min,然后电极加热6min,通电结束后氩气强吹6min,再氩气软吹1min,再次电极加热6min,通电结束后氩气强吹6min,再氩气软吹8min即可。
本实施例脱气后得到含有以下质量分数组分的钢液:C 0.12%、Si 0.3%、Mn 1.5%,P 0.012%,S 0.004%,Als 0.025,Nb 0.02%,Ti 0.013%,Ni 0.2%,O 0.002%、N 0.035%。
实施例3
与实施例1相比较,本实施例的不同点在于:
所述的脱硫工艺具体为首先氩气强吹3min,再氩气软吹3min,然后电极加热5min,通电结束后氩气强吹6min,再氩气软吹1min,再次电极加热6min,通电结束后氩气强吹3min,再氩气软吹8min即可。
本实施例脱气后得到含有以下质量分数组分的钢液:C 0.12%、Si 0.3%、Mn 1.5%,P 0.014%,S 0.003%,Als 0.025,Nb 0.02%,Ti 0.013%,Ni 0.2%,O 0.002%、N 0.03%。
以上实施例仅为本发明的示例性实施例,不用于限制本发明,本发明的保护范围由权利要求书限定。本领域人员可以在本发明的实质和保护范围内,对本发明做出各种修改或等同替换,这种修改或等同替换也应视为落在本发明的保护范围内。
Claims (4)
1.一种控氮核级特种钢的制备方法,其特征在于,包括以下步骤:
(1)将原材料送至高炉进行熔炼,得到铁水;
(2)铁水送至转炉,脱氧合金化阶段加入钢芯铝,在脱氧合金化结束至出钢结束期间加入造料渣,得到含有以下质量分数组分的钢包:C 0.09%、Si 0.02%、Mn 0.06%,P 0.014%,O0.03%、N 0.045%;
(3)转炉结束后的钢包送至吹氩站,根据钢液成分进行补加精炼渣和脱氧剂,再送至LF炉进行脱硫35~40min,然后进行RH脱气,脱气后得到含有以下质量分数组分的钢液:C0.12%、Si 0.3%、Mn 1.5%,P≤0.015%,S≤0.004%,Als 0.025,Nb 0.02%,Ti 0.013%,Ni0.2%,O 0.002%、N≤0.04%;
(4)出站后的钢液进行连铸,得到特种钢。
2.根据权利要求1所述的控氮核级特种钢的制备方法,其特征在于:所述的脱硫工艺具体为首先氩气强吹2~4min,再氩气软吹3min,然后电极加热5~6min,通电结束后氩气强吹6min,再氩气软吹1min,再次电极加热6min,通电结束后氩气强吹4~6min,再氩气软吹8min即可。
3.根据权利要求1所述的控氮核级特种钢的制备方法,其特征在于:所述的LF炉中,石灰用量为600~800kg/炉,萤石用量为60~80kg/炉。
4. 根据权利要求1所述的控氮核级特种钢的制备方法,其特征在于:所述的造料渣各组分的重量分数如下:CaO 55.20%,Al2O3 30%,SiO2 6.95%,MgO 8%。
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CN103276153A (zh) * | 2013-05-16 | 2013-09-04 | 武汉钢铁(集团)公司 | 降低焊接用钢盘条中氮含量的方法 |
JP2018016843A (ja) * | 2016-07-27 | 2018-02-01 | 新日鐵住金株式会社 | 極低硫低窒素鋼の溶製方法 |
CN106834610A (zh) * | 2017-02-07 | 2017-06-13 | 河钢股份有限公司承德分公司 | 一种高强微合金钢多段组合控氮方法 |
CN109252008A (zh) * | 2018-10-10 | 2019-01-22 | 新疆八钢铁股份有限公司 | 一种低碳低氮超低硫钢的生产方法 |
CN109338032A (zh) * | 2018-11-06 | 2019-02-15 | 芜湖新兴铸管有限责任公司 | Lf炉控氮精炼方法 |
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