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微波消解-电感耦合等离子体原子发射光谱法测定矿石样品中铌钽倪文山1,张萍1,姚明星1,李贤珍1(1.河南省郑州市地质科学院 郑州矿产综合利用研究所)摘 要:通过微波加热,氢氟酸溶解矿石样品,再以酒石酸溶液处理,使铌,钽完全进入溶液.以铌316.340{106}nm光谱线和钽268.517{125}nm光谱线为分析线,在选定的仪器参数下用电感耦合等离子体原子发射光谱法(ICP-AES)测定了溶液中的铌和钽.铌,钽原子发射光谱强度与ρ(Nb2O5)和ρ(Ta2O5)在0~6μg/mL范围内呈良好的线性关系,铌,钽的......
熔盐电脱氧制备金属铌的研究谢大海1,王兴庆1,陈发允1(1.上海市上海大学材料科学与工程学院)摘 要:采用熔盐电脱氧法,以熔融的CaCl2-NaCl为电解质,经粉末压制烧结后的Nb2O5为阴极,石墨为阳极,电解制备了金属铌.并研究了压制压力,烧结温度,电解时间等因素对Nb2O5阴极电脱氧的影响.实验分析表明:阴极脱氧过程是由Nb2O5→NbO2→NbO→Nb且由阴极表面到内部逐步进行的,在适宜条件下可以得到纯度为99.5%以上的金属铌.关键词:熔盐电脱氧制备； 金属铌； Nb2O5； 压制烧结......
: A Preparation of niobium by direct electrochemical reduction of solid Nb2O5 DENG Li-qin, XU Qian, LI Bing, ZHAI Yu-chun, HUANG Zhen-qi (School of Materials and Metallurgy, Northeastern University, Shenyang 110004, China) Abstract: The method of electro-deoxidation was used to reduce solid Nb2O5 to niobium in a CaCl2-NaCl melt at 800℃. The sintered Nb2O5 pellets acted as the cathode, while graphite......
热变形对高铌低碳钢奥氏体→铁素体等温转变影响研究曹建春1,周晓龙1,何寒1,陈文1,刘清友2,雍岐龙2(1.云南省昆明市昆明理工大学材料科学与工程学院2.钢铁研究总院 结构材料研究所,北京 100081)摘 要:针对热变形对铌质量分数为0.17%的低碳钢的奥氏体→铁素体等温相变动力学的影响,通过热模拟试验,分析未变形,875℃变形20%和30%条件下奥氏体向铁素体700℃等温转变的动力学,讨论了热变形和铌对奥氏体→铁素体等温相变的影响机制.研究结果表明:热变形主要通过缩短相变孕育期来加速奥氏体→铁素体等温相变;......
University, Changsha 410083, China; 3. Special Steel Branch, Baosteel Co.,Ltd., Shanghai 200940, China) Abstract: A MoSi2 coating on C-103 niobium alloy was prepared by packing cementation... oxidation circumstance, the dense amorphous glass scale is formed on the coating, which prevents the process of the oxygen diffusion to inner layer. Key words: niobium alloy; pack cementation; silicide......
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电感耦合等离子体原子发射光谱法测定钽中微量铌的多元光谱拟合干扰校正方法研究徐娟1,郑诗礼2,郭奋1,王晓辉1,张懿2(1.北京市北京化工大学化学工程学院2.中国科学院 过程工程研究所,北京 100190)摘 要:钽样品经氢氟酸消解后,未经基体分离,直接以多元光谱拟合等离子体原子发射光谱法测定消解液中微量铌杂质元素.Nb 269.706 nm分析谱线仅受到Ta基体的部分重叠光谱干扰,扫描光谱图较为简单;Nb 292.781 nm,Nb 309.418 nm和313.079 nm分析谱线均受到OH带和Ta基体的光谱......
Trans. Nonferrous Met. Soc. China 26(2016) 431-436 Segregation of niobium in laser cladding Inconel 718 superalloy Yi-tong LONG, Pu-lin NIE, Zhu-guo LI, Jian HUANG, Xiang LI, Xin-mei XU Shanghai Key... is widely used in the aerospace and turbine industry. Segregation of niobium appears in the laser cladding Inconel 718 superalloy and consequently influences the phase transformation during the rapid......
impedes the growth of Ti5Si3 phase, and the formation of TiO2 on surface and on Ti5Si3 phase is also impeded. Key words: TiAl based alloy; niobium silicon alloying; isothermal oxidation behavior... ℃ for 50 h [J]. Intermetallics, 2007, 15: 824-831. [6] LU Wei, CHEN Chun-lin, HE Lian-long, XI Yan-jun, WANG Fu-hui. Effect of niobium on oxidation behavior of TiAl [J]. Journal of Materials Research......
