影响VOD精炼的工艺因素

以工业试验和生产数据为基础,对不锈钢VOD法进行了分析,讨论了影响VOD过程的工艺因素。结果表明:通过合理控制真空度、氧枪高度、供氧强度及吹氩强度等参数,可以准确判断VOD吹炼终点,实现真空下"脱碳保铬"的有效控制。     

不锈钢高铬熔池中脱碳保铬的实践

本文引用了返回吹氧熔炼不锈钢的热力学原理,分析了在高铬熔池中温度—铬—碳—Pco之间的关系.在常压(Pco=1)的条件下,用大量的数据,从理论上和实践上论述了温度、供氧压力、熔清碳量和熔清铬量即Cr/C比值对脱碳保铬(即脱碳时铬的氧化损失)的效果,从中找出较佳工艺参数,来指导生产.     

VOD冶炼不锈钢碳、铬、硅等元素的氧化规律探讨

本文从6吨 VOD 炉实际冶炼18—8类型不锈锏出发,探索了真空吹氧过程中碳、铬、硅等元素的氧化规律。得出6吨 VOD 炉吹氧过程脱碳反应表现活化能为120Kcal/mol。温度对实际冶炼的影响比之在感应炉中的影响为大。求得小型 VOD 炉冶炼不锈钢时,氧化前期硅氧化的动力学随机模型为:[%Si]_t=0.934[%Si]_0exp(-0.088t)     

超低碳不锈钢冶炼技术研究

从热力学方面介绍了超低碳钢VOD冶炼吹氧时去碳保铬的影响因素,对ASTM A473钢的成品碳超标问题进行了原因分析,在操作上采取了改进措施。     

中频炉和VOD双联法冶炼不锈钢工艺

介绍了中频炉熔炼及VOD精炼X3CrNiMoN27-5-2不锈钢的生产工艺及措施.采用优质原材料,调整化学成分及出炉温度,控制VOD精炼炉吹氧真空度、吹氧强度、吹氧时间、氩气流最等工艺参数,并结合氧势图和废气温度,准确判断吹氧终点时间和极限真空保压时间,其冶金效果可以达到铸件材质的质量标准.     

铸造新材质ZG0Cr18NilNb耐热钢的熔炼

使用普通电弧炉，选择不含碳、高耐火度炉衬（镁铬砖衬），用高强度电极，采用微碳、低磷、低硫合金材料和强脱氧材料，先熔炼出低磷高镍精钢返回料，合理确定〔Ｃｒ〕／〔Ｃ〕，提高吹氧温度（１６２０℃），双管、大氧压供氧获得高脱碳速率，采取扩散、沉淀脱氧；保持渣的合适碱度（Ｒ＝２２～２６），控制〔Ｃｒ〕／〔Ｎｉ〕和〔Ｎｂ〕／〔Ｃ〕，最终达到降碳保铬、低硫磷、脱氧合金化目的，成功熔炼出ＺＧ０Ｃｒ１８ＮｉｌＮｂ耐热钢。     

Al_2O_3对镁铬耐火材料在炉外精炼渣中溶蚀的影响

提高真空吹氧脱碳(VOD)与氩氧脱碳(AOD)炉镁铬耐火材料炉衬的寿命,目前仍是重要问题,我们曾对不同Cr_2O_3含量的镁铬耐火材料在炉外精炼渣中的溶蚀进行了研究,本文采用同样实     

低压下高铬钢液脱碳和脱氮的实验研究

在200 kg真空感应炉上作了低压下高铬钢液脱碳和脱氮的实验研究,考察了精炼温度、初始碳和铬含量及真空度的影响。结果表明,精炼温度及初始碳和铬含量均会显著影响低压下高铬钢液的脱碳;适当提高精炼温度和真空度有利于高铬钢液的脱碳,高真空也有利于脱氮。     

低压下高铬钢液脱碳和脱氨的实验研究

在200kg真空感应炉上作了低压下高铬钢液脱碳和脱氮的实验研究,考察了精炼温度、初始碳和铬含量及真空度的影响。结果表明,精炼温度及初始碳和铬含量均会显著影响低压下高铬钢液的脱碳;适当提高精炼温度和真空度有利于高铬钢液的脱碳,高真空也有利于脱氮。     

CARBON-OXYGEN REACTION IN MOLTEN NICKEL AND NICKEL-10% CHROMIUM IN A VACUUM INDUCTION FURNACE

在电熔氧化镁坩埚中真空感应熔炼镍和镍-10％铬合金,于1500—1540℃温度和10~(-4)乇压力的条件下,通过三种不同方法(碳脱氧、氧脱碳)获得了10~(-5)-10~(-6)数量级的碳氧乘积;对碳氧反应的机理提出了看法。     

Oxygen refining of molten high-carbon ferromanganese

The effects of the oxygen/argon mixing ratio and temperature on the decarburization behaviour of high-carbon ferromanganese melts were investigated. The decarburization reaction was promoted and the oxidation reaction of manganese diminished by increasing temperature and decreasing the oxygen/argon mixing ratio. However, the carbon content in the melt appeared to increase during blowing at low temperatures and high oxygen/ argon mixing ratios because of faster manganese oxidation. An empirical equation was derived to predict the utilization ratio of oxygen for decarburization. The lower oxygen/argon mixing ratio and higher melt temperature were found to be essential in enhancing the efficiency of decarburization and suppressing the oxidation of manganese in the early stage of oxygen/argon refining of high-carbon ferromanganese melts.     

IF钢炼钢过程洁净度控制生产实践

涟钢通过优化转炉底吹、下渣控制、顶渣改质技术、缩短RH炉处理周期、严格控制RH炉吹氧量、稳定脱碳终点氧含量、提高一次加铝命中率、RH炉破真空到开浇镇静时间大于20 min,确保了夹杂物有充分的上浮时间,使得中间包钢水全氧低于2.5×10-5比例大于90%,IF钢夹杂降等量从2011年1.41%降低到目前0.15%,铝耗从2011年1.86 kg/t降低到目前的1.05 kg/t,钢水洁净度得到进一步改善。     

Effects of non-metallic inclusions on the initiation of pitting corrosion in 11% Cr ferritic stainless steel examined by micro-droplet cell

This paper explores the effects of non-metallic inclusions (NMIs) on the initiation of pitting corrosion in type 409L stainless steels refined by the argon oxygen decarburization (AOD) and vacuum oxygen decarburization (VOD) processes. The dominant NMIs in the AOD and VOD samples were (Ti, Ca)-oxides and Ti-nitrides, respectively. In-situ electrochemical noise (EN) and micro-electrochemical analyses were conducted to investigate quantitatively the inherent effects of the NMIs on the pitting corrosion of the alloys. Pitting corrosion was initiated mostly around the (Ti, Ca)-oxides in the AOD samples, while little such corrosion occurred around the Ti-nitrides in the VOD samples. In addition, the pitting resistance of the AOD samples increased with increasing Ti content and decreasing Ca content in the (Ti, Ca)-oxides.     

GCr15轴承钢制造工艺的研究

研究了初炼炉冶炼工艺、精炼渣系、真空度、真空保持时间、弱吹氩时间、钢锭模温度对轴承钢质量的影响,结果表明,合适的炉渣碱度、真空度≤30 Pa,真空保持时间≥15 min,弱吹氩≥8 min,保证钢锭模温度在30~100℃,可以生产出氧含量、夹杂物含量低及表面质量良好的轴承钢。     

VOD工艺在冶炼Z5CN12-04-M钢上的应用

简要介绍了VOD工艺在冶炼ZSCN12—04—M叶片钢上的成功应用。通过采用吹氧精炼和真空氧脱碳等工艺方法“保铬降碳”效果显著。结果表明:产品最终[C]=0.025％,VOD过程降C速率达到每分钟0.012％,总体Cr回收率达到87％,气体含量也达到了较低水平。     

Reduction mechanism of stainless steelmaking dust and carbon pellets

1 INTRODUCTIONThe smelting temperature generally reaches1 600 ℃or higher in stainless steel making opera-tion. Under this condition,approxi mately 1 % 2 %(mass fraction) of the scrap charged into the fur-nace is converted to dust[1]as by-product of steel-making process .It has been assigned as a hazard-ous waste and banned from landfills by variousgovernment regulatory agencies because it containsa lot of heavy metals such as zinc ,lead,cadmium,chromium and nickel , which will be leached …     

控制含硫钢A类夹杂的生产实践

"BOF-LF-VD-CC"工艺流程生产含硫钢,在VD真空处理前,钢中[O]含量≤10×10-4%,[S]含量≤0.005%。钢液温度≥1 600℃时,按0.02 kg/t进行钙处理,VD真空保持时间≥10 min,软吹时间≥15 min,VD破空后按0.035%~0.040%喂入硫磺线。结果表明,连铸过程保护浇注、禁止下渣,可控制含硫钢轧材A类夹杂细系/粗系级别分别≤2.0级。     

Chromized Layers Produced on Steel Surface by Means of CVD

DIFFUSION CHROMIZING is one of many types ofthermochemical treatment employed today forimproving properties of steel surface such as hardness,wear and corrosion resistance[144].In this paper,anovel CVD method that combines the low cost of packmetallization and the advantage of vacuum techniquewas investigated[5].The coating process was based onthe formation of chromium chlorides atmosphere in situduring the processing.A metallic chromium powdermixture with a halide activator(NRiCl)we…