高温合金定向凝固过程中通道偏析的物理模拟研究

利用NH4Cl-H2O溶液凝固实验,对高温合金定向凝固中的通道偏析进行物理模拟,研究通道偏析的形成过程以及溶液中NH4Cl的质量分数w(NH4Cl)和初始基板温度对通道偏析数目和形貌的影响。结果表明,除了w(NH4Cl)为15%外,w(NH4Cl)为24%、27%和30%的NH4Cl-H2O溶液凝固时均形成通道偏析。随凝固时间延长,通道偏析数目先逐步增加然后减少,形貌辨识程度增加。随w(NH4Cl)增加,通道偏析数目减少,形貌辨识程度增加。随初始基板温度下降,通道偏析数目减少,形貌辨识程度增加。影响通道偏析的主要因素可归结为影响偏析形成和通道形成的因素,包括合金成分、温度梯度和凝固速率。     

石蜡相分光光度法测定汞的研究

研究以双硫腙为显色剂,石蜡为固体萃取剂,石蜡相分光光度法测定污水中汞。结果表明:汞-双硫腙络合物(Hg(HDZ)2)在pH10.0NH3.H2O-NH4Cl介质中可以定量地被石蜡萃取,30mL溶液中汞在0～20μg范围内符合比尔定律。除铅、铋、锌外,其他共存离子对测定无干扰,铅、铋、锌可在pH1.2时用双硫腙萃取除去。方法用于污水中汞的测定,RSD为3.3%,结果比较满意。     

P204萃取分离锑铁工艺研究

萃取分离锑铁是脆硫锑铅矿矿浆电解工艺过程的一个环节。P2 0 4可选择性地在NH4 Cl介质溶液中萃取铁。在 35 %(体积百分数 )P2 0 4、相比 (O/A) 1∶1、3级连续逆流萃取条件下 ,铁萃取率达 80 %～ 84%,锑、银基本不被萃取。含Fe总 1～ 1 4g/L的萃余液可返回矿浆电解循环使用。     

MgCl2溶液对烧结矿低温还原粉化率的影响

试验测定了 Mg Cl2 溶液不同浓度和喷洒量对济钢现有原料条件下烧结矿低温还原粉化率 (RDI)和还原度 (RI)的影响。结果表明 :每 5 0 0 g烧结矿喷洒 10～ 2 0 m L浓度为 1.0 %～ 3 .5 %的 Mg Cl2 溶液 ,能显著降低烧结矿的 RDI,且还原度不受影响 ,以 5 0 0 g烧结矿喷洒浓度为 2 .5 %的 Mg Cl2 溶液 10 m L综合效果最佳 ,可使烧结矿的 RDI从 3 6%降至 4.4%。     

从废旧高温合金中提取Re的试验研究

针对高温合金高致密性、难溶解的特点,采用真空气雾化法将废旧高温合金制成活性很高的细微颗粒,再经氧化酸浸后,废旧高温合金粉中的Re以ReO-4形态进入溶液,Re浸出率达99.02%;酸浸液用NaOH饱和溶液调pH值至1.5后,用D296型阴离子交换树脂吸附Re,Re吸附率达98.76%;解吸过程中先用NH3·H2O+NH4Cl混合溶液解吸D296负载树脂上的Mo,Re损失率为4.97%,再用NH4SCN溶液解吸Re,Re解吸率达94.98%;含Re解吸后液可通过添加KCl或NH4Cl蒸发浓缩冷却结晶工序制备含Re产品,控制浓缩液中Re浓度大于22.38g/L,Re结晶率可达90%以上。X射线荧光光谱分析结果表明,所获得的KReO4和NH4ReO4产品纯度分别达到了99.21%和99.58%。     

溴酸钾氧化偶氮胂M褪色动力学光度法测定痕量铊(Ⅲ)

基于0.08mol/LH2SO4介质中,痕量铊(Ⅲ)催化溴酸钾氧化偶氮胂M(AsAM)的褪色反应,建立了测定痕量铊(Ⅲ)的催化光度法。讨论了酸度、反应物浓度、反应温度、时间、干扰离子等因素的影响。研究了反应的最佳条件,并测定了一些动力学参数,催化反应的表观活化能为70.12kJ/mol。方法检出限为0.17μg/L,线性范围为0～20μg/L。在25mL溶液中,测定0.5μg铊(Ⅲ)的相对标准偏差为3.4%(n=11)。结合溶剂萃取分离技术,用于测定废水及土壤样品中痕量铊(Ⅲ),回收率为97.0%～103     

水杨醛肟催化光度法测定煤矸石中痕量锰

研究了在NH3·H2 O -NH4 Cl缓冲溶液中痕量锰 催化过氧化氢氧化水杨醛肟 (SAO)的显色反应 ,催化程度与Mn 量在一定范围内呈线性关系。借此建立测定痕量Mn 的催化光度法。结果表明 ,有色溶液的最大吸收波长为 410nm ,方法检出限为 1.2× 10 -11g/mL ,催化程度与Mn 量在 0～ 0.30 μg/2 5mL范围内符合比尔定律 ,可用于测定煤矸石中的痕量锰     

原子吸收法快速测定金精矿中的银

采用王水+H2O2+NH4Cl+HF溶样体系封闭溶样法对金精矿进行预处理,制得样品溶液后以原子吸收法测定银;其测定范围1000 g/t,RSD为4.5%,测定60个样品仅需3 h。该方法具有简单快速、成本低、对环境友好等特点,其分析结果可满足选冶工艺生产的要求。     

废杂铜氨性蚀刻溶铜工艺研究

研究了在CuCl2-N H3-N H4 Cl和CuCl2-CuSO4-N H3-N H4 Cl体系中蚀刻废杂铜,考察了蚀刻液组成、铜氨溶液中初始离子质量浓度、温度、溶液流动状态、蚀刻液 pH 等因素对铜溶解速率的影响。结果表明：CuCl2-NH3-NH4Cl体系中,在铜质量浓度120～165 g/L、氯质量浓度150～200 g/L、pH 8．0～8．5、温度45℃、强化流动条件下,废杂铜的蚀刻速率为0．25 g/（min · L ）;CuCl2-CuSO4-N H3-N H4 Cl体系中,在铜质量浓度35～75 g/L、氯质量浓度35～80 g/L、p H 10．0～11．0、温度45℃、强化流动条件下,废杂铜的蚀刻速率为0．33 g/（min · L ）。     

离子交换分离-电感耦合等离子体原子发射光谱法测定锰矿中铊

锰矿用盐酸、硝酸、氢氟酸和高氯酸溶解,以氢氧化钠溶液调整试液酸度至pH 1.7～2.0,用溴水氧化Tl 为Tl,过D401离子交换树脂柱,经0.015 mol/L硝酸淋洗后,用2 mL 3 g/L亚硫酸溶液还原柱上的Tl为Tl,再用0.015 mol/L硝酸洗出Tl,选择Tl 190.857 nm为分析谱线,电感耦合等离子体原子发射光谱法(ICP-AES)测定分离后溶液中的铊。方法中铊的检出限为1 ng/mL,测定下限为0.8 μg/g。干扰试验结果表明,测定0.1 μg/mL铊,不大于50 μg/mL铁、2 μg/mL锰、10 μg/mL铝、镉、铬、镍、铅、锌不干扰。一般锰矿样品按实验方法分离和测定,铁、锰、铝、镉、铬、镍、铅、锌不影响铊的测定。按照实验方法测定锰矿样品中的铊,测定结果的相对标准偏差(RSD,n=8)在1.6%～11%之间,加标回收率为90%～108%。     

熔炼次数对M17返回料合金成分、组织和性能的影响

实验结果表明,M17铸造高温合金(%:0.16C、8.79Cr、5.79A1、4.93Ti、3.29Mo、15.20Co、0.78V、0.015B、0.073Zr、0.002S、0.001P、0.001 1O、0.001 0N)经25 kg真空感应炉返回重熔后,Si含量随重熔次数的增加而略有增加,合金中主要元素和其它杂质元素S、P、H的含量变化不大,而氧、氮略有增加;合金中初生碳化物由新合金中的草书体逐渐向返回合金块状转变,初生碳化物的遗传性堵塞合金凝固时的补缩通道,使返回料合金的疏松倾向增大,高温塑性下降较大。     

Shijiazhuang will Build the World's Biggest Replacingcopper-with-aluminum Cable Production Base

正Shijiazhuang City will build the world’s biggest replacing-copper-with-aluminum cable production base,the annual output value can reach 100 billion yuan,in the future it will develop replacing-copper-with-aluminum highend industry cluster.This piece of news was learned by the reporter at the Rare Earth highiron Aluminum Alloy[Nonferrous Business Opportunity:Aluminum alloy door]Cable Conductor New Technology Application Seminar held at the provincial capital.     

Chongqing is Preparing to Set Up Nonferrous Metal Exchange,in a Bid to Become the Transit Place of Kazakhstan Copper

正Since the beginning of Chongqing’s upgrading to a municipality directly under the Central Government,Chongqing City has established direct friendly relationship with Almaty,Kazakhstan,and carried out a series of cooperation in commerce and trade,and culture     

Guangxi Baise Extends Industrial Chain to Combat Loss in Aluminum Business

正"For each tonne of aluminum being produced,the upstream enterprise on the aluminum industrial chain will suffer loss about 2000yuan."Said Liang Xiao,Deputy Director of Pingguo Industrial Park Management Committee under the Guangxi Baise City,one of the four major aluminum industry bases in China,on August 11.Extending aluminum     

JOURNAL OF IRON AND STEEL RESEARCH INTERNATIONAL ANNUAL CONTENTS Volume 21(2014)

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Chinalco Straightened Out Copper Assets,and Delegated Stock Equity of Yunnan Copper

正Immediately after the news that Chinalco transferred 58%stock equity of Yunnan Copper Group to its wholly-owned subsidiary China Copper Corporation Limited free of charge was disclosed on July 9,many individual investors couldn’t help but to think:Does it mean China Copper Corporation Limited will assemble assets for overall listing?At present,among main copper business companies under China Copper Corporation     

The Development and Reform Commission Encourages Private Capital to Enter Geological Prospecting Field

正At the press conference recently held by the National Development and Reform Commission under the theme"Deepen Reform in Investment AuditApproval System",when answering questions from reporters,Huang Min,Director of the Department of Fixed Assets Investment of the National Development and Reform Commission,said that in the future it would continue to intensify efforts in geological prospecting,and actively guide social capital to enter this field.     

Guangxi's first Nickel Industry Development Research Report Was Released

正Recently,Guangxi Metallurgical Research Institute,a subsidiary of Guangxi Nonferrous Metals Group,completed survey on laterite and related manufacturers in the region,by combining the current development status of laterite both at home and abroad,it compiled Guangxi’s first"Research Report on the Development of Guangxi Nickel Industrial Chain"which adopted laterite as the study subject.This report expounded on the current     

China’s Major Non-ferrous Metals Imports & Exports(End of September. 2014)

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China's Major Non-ferrous Metals Imports & Exports

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