11% 1 2, (1. ( ), 735100; 2. ( ), 735100) 11%, 11% 11%, Al2O3, O Al Ti 11% ; ; ; A 1006-9356(2015)11-0045-06 Mechanismonnozzleblockageofultrapurified 11%Crferriticstainlesssteels LIYan 1, LIJu-cang 2 (1.TechnologyCenter,JiuquanIronandSteel(Group)Co.,Ltd.,Jiayuguan735100,Gansu,China; 2.HongxingIronandSteelCo.,Ltd.,JiuquanIronandSteel(Group)Co.,Ltd.,Jiayuguan735100,Gansu,China) AbstractCombined withactualproduction data,the mechanism on nozzleblockageduringcontinuouscasting processofultrapurified11%crferritestainlesssteels(11%crup-fss)wasinvestigatedbymetalurgicalobserva- tionandenergyspectrumanalysisaswelasthethermodynamiccalculationfortitaniumandaluminumoxidesforma- tion.theresultshowedthatnozzleblockageof11%crup-fsswasmainlycausedbythehighti-oxidescontentin moltensteel.duringthecastingprocess,thecompoundoxidesgeneratedfromthereactionbetweenti-oxidesand Al2O3innozzlerefractoryadheredtothenozzlewal,enrichedcontinuouslyandadsorbedotherinclusionsandmol- tensteel,whichcanmakethenozzlewalthicker.nozzleblockageof11%crup-fsscanbeefectivelyprevented throughcontrolingtheo,al,ticontentsinsteel,usingdeepdeoxidizationduringsmeltingprocess,increasingthe softblowingtimeandholdingtime,preventingthesecondaryoxidationandcastinginhigherdegreeofsuperheat. Keywordsnozzleblockage;compoundoxides;softblowing;holding;superheat,,, 10%~14% ;,,,, [1-5],, 1,,, 11% AOD LF [6-8] CCM AOD 11%,, LF, (1964 ),,, ; E-mailliyan@jiugang.com; 2014-12-18 (1969 ),,, ; E-maillijucang@163.com
,,, 1 2 1 11% ( ) Table1 Chemicalcompositionof11%Crslab % C Si Mn P S Ni Cr Cu Al Ti N O 4701757 0.014 0.417 0.276 0.0192 0.0007 0.1 11.45 0.019 0.008 0.2004 0.0114 0.003 2 e (K) B (1873K) Table2 Interactioncoeficientsofelementsin 2 liquidiron,e (K) B (1873K) % 2.1 Al C Cr N O Si Ti 2.1.1 Ti -0.165 0.055-1.8-1.8 0.05 0.013 1 Al 0.045 0.091-0.053-6.6 0.0056 1, O -3.9-0.45-0.04 0.057-0.2-0.131-0.6, (5) ( 1, 1873K), ; (a) ( ); (b) ; (c) ( ) Fig.1 1 Metalographicobservationforscafold-formingmaterial, ; 2.1.2 2.2 (1) 11% 2, (2) 3 11%,,, Ca-Ti, (3) 4,, ( 15 mm ) LF,,, Ti-Al (, 5 2); Mg-Al-Ti-Ca 5 ( 3); 0.01%,, ( 4) 0.01% Al 2O 3, LF 0.005%,
第 １１ 期 李 岩 等 超纯 １１ 铬铁素体不锈钢水口结瘤机理 水口结瘤实物照片 ｂ 水口结瘤物外层电镜微观形貌图 １ 点能谱图 ｄ ２ 点能谱图 图 ２ 靠近水口结瘤物分析 Ｆ ２ Ｅｎ ｕｍ ｎ ｓ ｓ ｓ ｄ ｍ ｎｇｍ ｎ ｈ ＳＥＭ ｇ ｇ ｙｓ ｐ ｙ 水口结瘤物中部电镜微观形貌图 ｂ １ 点能谱图 ２ 点能谱图 ｄ ３ 点能谱图 图 ３ 结瘤物中部分析 Ｆ ３ Ｅｎ ｕｍ ｎ ｓ ｓ ｈ ｍ ｄｄ ｐ ｓ ｄ ｍ ｎｇｍ ｇ ｇ ｙｓ ｐ ｙ ４７
(a) ; (b)1 ; (c)2 ; (d)3 4 Fig.4 Energyspectrumanalysisfortheinteriorofscafold-formingmaterial (a) ; (b) ; (c) 5 Fig.5 Statisticsforprocesofproduction 2.3, 2.3.1 Al 2O 3,, Al 2O 3 11%,, Al 2O 3 Ti 2O 3,Al 2O 3 TiO 2,, [3] 1500~1550,,Al 2O 3, TiO 2, 1860, ;AOD LF Al 2O 3 (s)+tio 2 (s)= Al 2O 3 TiO 2 (s) ΔrG θ m1=-25300+3.93t (1), ; ΔrG θ m1,j/mol;t,k AOD, 2.1.2,, 20min,
40min,,, 2.3.2 [9], 2[Al]+3[O]=Al 2O 3 11% 0.01%, 0.01%, 0.009%, ( 36 10-6 ),,kj/mol;t,k;k ΔrG θ m4= -1502100 + 258.1T (7) ;α B ;fb B 2 (7) fti=4.22, ;e B ;w fo=0.21,% (1555 ), 11% (2)~ (5) 1 2 fal=0.96 (1555 ), 11% w Ti w O2 =5.449 10-7 w 2 Ti wo3 =1.769 10-12 w Al 2 wo3 =7.619 10-13, [10-15] 0.01%,, 2.3.3 11% Ti 2O 3 ΔrG θ m2= -1202000 + 386.39T (2) TiO 2 ΔrG m= ΔrG θ m2+ RTlnK θ (3) [9] TiO 2 Ti 2O 3 αb =fbw B (4) [Ti]+2[O]= TiO 2 lgfb =e (B) B w B +e (3) B w 3 + +e (K) B w K (5) ΔrG θ m3= -941000+177.57T (6) ΔrG m,kj/mol;δrg m2 2[Ti]+3[O]= Ti 2O 3 11% 1 2, 11% 7 (1592 LF,1555,1505 ), 6 7 Fig.7 StablitydiagramofTiOXinsteel 6 Al2O3 Fig.6 StablitydiagramofAl2O3insteel (1)Ti 2O 3 TiO 2 6, (2),,, LF, 11%, (3) 0.2%, LF
Ti 2O 3 0.0006%,TiO 2 0.0025% 1 LF (4)LF, Al 2O 3 [15] Ti 2O 3 TiO 2 (5)LF 20min, 40min, Ti 2O 3 TiO 2 8 9 (6),LF, 3 8 Ti2O3 Fig.8 StablitydiagramofTi2O3 9 TiO2 Fig.9 StablitydiagramofTiO2 (1) 11% Al 2O 3 (2) 11% Ti 2O 3 TiO 2, (3) w C+w N, 240 10-6, (4),,, 0.01%,0.009%, (5)LF,,, (6) 20min, 40min, 50,, (4),,, 2.3.4 [J]., [4].,2008,116(6)26. (1),,AOD, (5)1541. (2), w C+w N, w C+w N, w C+w N 240 10-6 (3), 50 [1],,,.409L,2011,46(6)40. [2],,,.409L 430 [J].,2011,33(4)28. [3],.409L 410L [J].,2008(8)53. 409 [J]. [5] KrawiecH,VignalV.Dissolutionofchromium-enriched inclusionsandpitingcorrosionofresulfurizedstainlesssteels [J].Metal Mat Trans APhys Metal MatSci,2006,37 [6],,,.304 321 [J].,2004,26(6)596. [7],,,. [J].,2005,17(1)14.
[8],,. inspinelsolidsolutionandfreeenergiesofformationofmgo, [J].,2010(5)1. MgO Al2O3[J].ISIJInternational,2000,40(11)1059. [9]. [M].,2005. [13],,,.409L [10],,,. [J].,2010,31(6)848. [J].,2008,29(1)16. [11] NishiT,ShinmeK.Formationofspinelinclusionin molten stainlesssteelunderaldeoxidation withslag[j].tetsu-to- Hagane,1998,84(12)837. [12] FujiK,NagasakaT,Hino M.Activitiesoftheconstituents [14],,.BOF-LF-CSP SPHC [J].,2013,25(3)23. [15],,. [J].,2013,35(9)1138.