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稀土和镁同样是球墨铸铁的一种优良球化剂。但稀土元素的熔点高,比重大。当加入铁水之后,如果没有充分的搅拌,往往不能充分发挥其作用。目前传统采用的是以压入或冲入法向铁水中加入稀土,由于动力学条件差,稀土元素与铁水不能充分熔合,导致球化效果不佳,并使加入稀土量增加, 相似文献
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生产25CrMoBVRE和U76CrRE试验采用钢包投入法加入稀土合金,经铁水预处理、转炉冶炼、采用脱氧合金化工艺,在LF钢包精炼采用深脱硫工艺,精炼后,钢水中硫含量及氧含量很低,对提高稀土收得率有积极作用。通过有效控制钢水的氧、硫含量,分别在VD前、后钢包中进行加入稀土镧硅钙铁合金、稀土铈铁合金,稀土加入量分别为0.012%和0.003%,试验结果表明,采取相应的保护浇注措施,未出现水口堵塞现象,生产工艺顺行,操作方便,稀土收得率分别达到15%和40%。成本降低分别为60%和50%。稀土在钢中分布均匀,有改善夹杂物作用,产品性能完全满足产品标准及用户使用要求。 相似文献
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分析了铁水脱硫时铁水温度、铁水量、初始硫含量、脱硫后硫含量对镁粉耗量的影响,表明:随铁水温度增加镁粉耗量随之增加;随脱硫后硫含量的降低,镁粉耗量明显增加且增幅逐步扩大,为降低成本,脱硫深度应控制合理。为确定合适的粉剂用量,建立了基于BP神经网络和回归的铁水脱硫粉剂预报模型,其中BP神经网络模型是粉剂模型的主输出,回归模型用于限定输出范围。铁水脱硫粉剂预报模型已实现了在线控制,无需人工干预,达到了较好的应用效果。当偏差区间为[-0.001 5%,0.001 5%]时,脱硫后硫含量的符合率为90.85%,可有效实现脱硫后硫含量的控制。 相似文献
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探讨了用ICP -AES法对铜合金中多元素分析的基本条件 ,确定了合适的谱线和背景校正方法 ,基本解决了基体干扰和待测元素间干扰。方法用于铜合金中磷、铋、镍、铁、锑、锡、铅的分析 ,相对标准偏差小于 10 % ,标准加入回收率为 95 %~ 10 5 % ,方法快速简捷 ,准确度高 相似文献
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土壤无机污染物铅、铬、镉、汞、砷、锌、铜、镍这八大重金属,是一般土壤检测中的必检项目。金属元素在土壤中积累富集后,有可能通过雨水迁移,造成地下水,地表水污染,或者通过农作物进入食物链,进而影响食品安全和人体健康,因此,对这些元素的检测显得尤为重要。本文采用原子荧光光谱法对土壤中的金属元素进行测量,同时结合微波消解技术对样品进行处理,确保测量数据的准确性。 相似文献
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本文介绍了一种光谱定量分析方法。该方法使用BYG01-1氧化铜光谱标准样品,对1-4号纯铜中铋、锑、砷、铁、镍、铅、锡、锌8个杂质元素进行定量分析。分析方法简单,测定结果与化学结果基本相符。方法的测定下限为3×10 ̄(06)。 相似文献
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ICP-AES法测定铸铁中的镧、铈、镨、钕、钐 总被引:1,自引:0,他引:1
应用ICP-AES法测定铸铁中稀土元素镧、铈、镨、钕、钐可优化ICP的工作参数,选择合适的分析谱线,精密度良好,相对标准偏差<5%,回收率在95%~101%之间. 相似文献
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探讨了火花源原子发射光谱法分析银中杂质元素铜、铋、铁、铅、锑、钯、硒和碲的分析条件、样品处理方法, 确定了各杂质元素测定范围。采用对测定结果无明显影响的车床或压样机加工样品表面, 用盐酸(1+9)去除试样表面的沾污, 校准曲线采用仪器内置的纯银标准曲线, 并通过内部质量控制样品和校正样品监控。实验方法用于纯银标准样品中8种元素的分析, 测定值与认定值一致;对银锭样品进行分析, 各元素11次测定结果的相对标准偏差在1.0%~4.0%之间。方法可用于纯银和银锭中包括钯的杂质元素分析。 相似文献
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YOU Xiang-mi JIANG Zhou-hua LI Hua-bing 《钢铁研究学报(英文版)》2007,14(4):24-30
The grades of ultra-pure ferritic stainless steels, especially the grades used in automobile exhaust system, were reviewed. The dependence of properties on alloying elements, the refining facilities, and the mechanism of the reactions in steel melts were described in detail. Vacuum, strong stirring, and powder injection proved to be effective technologies in the melting of ultra-pure ferritic stainless steels. The application of the ferritic grades was also briefly introduced. 相似文献
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ZHOU Jiaxi HUANG Zhilong ZHOU Guofu LI Xiaobiao DING Wei BAO Guangping 《Canadian Metallurgical Quarterly》2011,85(1)
Trace elements and rare earth elements(REE)of the sulfide minerals were determined by inductively-coupled plasma mass spectrometry.The results indicate that V,Cu,Sn,Ga,Cd,In,and Se are concentrated in sphalerite,Sb,As,Ge,and Ti are concentrated in galena,and almost all trace elements in pyrite are low.The Ga and Cd contents in the light-yellow sphalerites are higher than that in the brown and the black sphalerites.The contents of Ge,Ti,In,and Se in brown sphalerites are higher than that in light-yellow sphalerites and black sphalerites.It shows that REE concentrations are higher in pyrite than in sphalerite,and galena.In sphalerites,the REE concentration decreases from light-yellow sphalerites,brown sphalerites,to black sphalerites.The ratios of Ga/In are more than 10,and Co/Ni are less than 1 in the studied sphalerites and pyrites,respectively,indicating that the genesis of the Tianqiao Pb-Zn ore deposit might belong to sedimentary-reformed genesis associated with hydrothermal genesis.The relationship between LnGa and Lnln in sphalerite,and between LnBi and LnSb in galena,indicates that the Tianqiao Pb-Zn ore deposit might belong to sedimentary-reformed genesis.Based on the chondrite-normalized REE patterns,δEu is a negative anomaly(0.13-0.88),andδCe does not show obvious anomaly(0.88-1.31); all the samples have low total REE concentrations(<3ppm)and a wide range of light rare earth element/high rare earth element ratios(1.12-12.35).These results indicate that the ore-forming fluids occur under a reducing environment.Comparison REE compositions and parameters of sphalerites,galenas,pyrites,ores,altered dolostone rocks,strata carbonates,and the pyrite from Lower Carboniferous Datang Formation showed that the ore-forming fluids might come from polycomponent systems,that is,different chronostratigraphic units could make an important contribution to the ore-forming fluids.Combined with the tectonic setting and previous isotopic geochemistry evidence,we conclude that the ore-deposit genesis is hydrothermal,sedimentary reformed,with multisources characteristics of ore-forming fluids. 相似文献