黄铜表面富植酸钝化工艺研究

采用植酸(50%,质量分数)8 ml.L-1,双氧水(30%,质量分数)30 ml.L-1,硼酸5 g.L-1,聚乙二醇15 ml.L-1,添加剂4 g.L-1钝化液对冷轧HAl72-2.5-1黄铜带材进行钝化处理,探讨工艺条件(钝化温度、钝化时间和钝化液pH值)对富植酸钝化膜耐蚀性的影响。通过硝酸溶液点滴腐蚀试验对黄铜表面富植酸钝化膜的耐腐蚀性能进行研究。结果表明,富植酸钝化膜的最佳工艺条件为:钝化温度范围是35～40℃,pH值为2.5,钝化时间为60 s。SEM微观形貌显示,膜层表面平整,结构致密。失重试验结果表明:经富植酸处理的试样的平均腐蚀速率为0.0054 g.m-.2h-1,与重铬酸盐处理的试样的平均腐蚀速率(0.0040 g.m-.2h-1)相当,比未经钝化处理的试样的腐蚀速率(0.0376 g.m-2.h-1)低的多,说明采用富植酸钝化处理能对合金材料起到很好的保护作用。经过12 h的盐雾法试验显示:经重铬酸盐处理的试样表面有较多的褐色斑点,表面颜色不均匀,而经过富植酸处理的试样表面为金黄色,只有少量的腐蚀斑,说明采用富植酸处理的试样比采用重铬酸盐处理的试样具有更好的抗变色能力。富植酸钝化液中不含铬,废液中不会产生铬污染。     

锌表面稀土化学钝化及耐蚀性研究

采用三价铈盐对锌进行化学钝化处理 ,研究了有关工艺参数对锌表面稀土转化膜耐蚀性的影响 ,测量了钝化过程中试样的交流阻抗谱 (EIS)和表面显微硬度的变化 ,探讨了稀土转化膜的形成机理 ,并对成膜动力学进行了分析。随着钝化液的铈盐浓度、pH值、温度和处理时间的增加 ,稀土转化膜的耐蚀性也相应提高 ,一定条件下可达到或优于铬酸盐钝化的防蚀性能。稀土钝化成膜反应动力学符合Arrhenius方程 ,反应活化能约为 6 4 8kJ/mol。     

合金化热镀锌板辊涂法无污染铬酸盐处理研究

采用先进的辊涂法铬酸盐预处理工艺,可获得性能优良的有机涂层钢板,并可消除由Cr(Ⅵ)引起的污染问题。 本研究采用优选法设计预处理技术参数的条件试验,并辅以化学分析、电镜、俄歇、电化学测试等手段进行。 实验结果表明:采用辊涂法预处理液C50可获得耐蚀性、涂装性及加工性均优的合金化热镀锌有机涂层钢板。C50的技术参数为:CrO_25～30g/L、NaF0.2～1.0g/L、添加剂A0.2～0.9mL/L、溶液温度30～55℃、基板温度60～80℃、烘烤温度90～120℃、处理时间4～6s、溶液pH值0.9～1.3;处理膜内Cr(Ⅲ)/Cr(Ⅵ)比值对膜的耐蚀性有直接影响,一般在3.3～5.5为宜;添加剂A具有使膜中Cr(Ⅲ)向Cr(Ⅵ)转化的作用;溶液C50各参数对处理膜的耐蚀性均有影响,其中pH值的影响较为显著;另外,本研究还对溶液与基板界面的化学反应情况进行了初步的探索。     

共沉淀法合成CeO2/γ-Al2O3复合纳米晶的研究

以Al(NO3)3·9H2O和Ce(NO3)3·6H2O为原料,氨水为pH值调节剂,并加入少量表面活性剂PEG4000,采用化学共沉淀法制备了前驱体,前驱体经高温热处理得到含25%(质量分数)CeO2的CeO2/γ-Al2O3复合纳米晶。通过正交试验,获得了共沉淀的优化条件:pH值为9～10,反应温度约30℃,反应时间为20min,表面活性剂用量为0.44%(质量分数),前驱体热处理温度800℃为宜。使用TG/DTA、XRD、BET、IR、纯度及化学成分分析等方法对CeO2/γ-Al2O3复合纳米晶的性能进行了表征。     

6061铝合金表面稀土铈盐法处理工艺研究

采用稀土盐Ce(NO_3)_3·6H_2O作为主盐、H_2O_2为强氧化剂,研究出新型6061铝合金无铬转化工艺,并通过抗蚀性能测试、转化膜膜厚测试等方法对其转化后的耐腐蚀性能进行分析。结果表明,最佳成膜工艺参数,Ce(NO_3)_3·6H_2O浓度为15g·L~(-1);H_2O_2浓度为4m L·L~(-1);处理温度为35℃,处理时间为10 min;pH为3.5。稀土铈转化膜的生成可以显著降低6061铝合金的腐蚀速率,提高金属基体的耐腐蚀性能。     

pH对碳酸铈粒子团聚的影响

在不同的(NH4)2CO3和Ce(NO3)3摩尔比值R、初始料液Ce(NO3)3溶液的pH以及(NH4)2CO3加料时间条件下制备了Ce2(CO3)3粒子,并用SEM和Zeta电位仪对其进行表征。结果表明,溶液pH对Ce2(CO3)3粒子形貌无影响,只是使得溶液离子浓度及双电层厚度发生改变,进而引发Ce2(CO3)3粒子的团聚。当R=1.6、pH=4、加料时间1h时得到的Ce2(CO3)3形貌最好,颗粒分散性好。     

化学转化处理时间对2198铝锂合金硝酸铈转化膜耐蚀性的影响

选用2198铝锂合金作为实验材料，以Ce(NO₃)₃为成膜主盐、H₂O₂作为氧化剂，在其表面制备了一种环保型稀土化学转化膜。采用化学浸泡法，在30℃的温度下对合金进行不同时间的化学转化处理，研究化学转化时间对合金硝酸铈转化膜耐蚀性的影响。测量化学转化膜形成过程中Ce(NO₃)₃溶液的pH变化，试样的开路电位和重量变化；利用扫描电镜和能谱(SEM/EDS)以及X射线光电子能谱(XPS)对化学转化膜层表面形貌进行观察，并对膜的组成进行分析；利用极化曲线和电化学阻抗谱(EIS)研究转化膜的耐蚀性能。结果表明：2198铝锂合金表面生成的化学转化膜呈深黄色，生成的化学转化膜能够覆盖合金表面，含有Al,Ce,O和少量的Cu元素。XPS分析表明，2198铝锂合金的化学转化膜的主要成分为Ce(OH)₄,Ce(OH)₃,CeO₂,Ce₂O₃和Al₂     

Ce掺杂Cu_2O(Ce/Cu_2O)薄膜的制备及其光电性能

用NaAc与Cu(Ac)_2为反应体系,采用电沉积法,在ITO上制备了Ce掺杂的Cu_2O(Ce/Cu_2O)薄膜。探讨了Cu(Ac)_2浓度、沉积温度、沉积时间、沉积电压和溶液pH等制备条件对Cu_2O样品光电性能的影响及Ce掺杂量对Cu_2O薄膜光电性能的影响。结果表明,当反应液中含0.04 mol/L Cu(Ac)_2、0.02 mol/L NaAc、0.0064 mmol/L CTAB、0.008 mol/L Ce(NO_3)_3、溶液pH为5.5、沉积温度为50℃时,在1.4 V电压下沉积40 min,即可制备形貌较好、光电压达0.3239 V的Ce/Cu_2O薄膜,Ce的掺杂有着比单纯Cu_2O薄膜更高的光电性能。UV-vis、XRD、SEM和EDS等表征结果显示,Ce的掺杂使得Cu_2O薄膜紫外吸收峰发生蓝移、抑制了Cu_2O微晶的生长、使薄膜的形貌变为叶脉较宽的星型枝叶状,样品中Ce元素质量分数和原子分数分别为22.63%和8.78%。     

钢铁化学法磷化发黑工艺研究

介绍了一种钢铁化学法着黑色溶液的组成及工艺参数：K2Cr2O710g/L、MnSO4 4g／L、(NH4)2SO4 20g／L、Zn(H2PO4)2 20g／L、KNO3 12g／L、CuSO4 6g／L、添加剂A(钼酸铵)2～3g／L、添加剂B(柠檬酸盐)3g／L、H3PO4适量、pH值为1．5～2．5、温度为10．25℃(室温)、时间为12～18min。分析了该着色液着色的机理，着重讨论了该配方各组分的作用及其对着黑色膜质量的影响。实验结果表明：该工艺发黑具有着色时间短、环境污染小、黑膜附着力强、光泽性好特点，同时该膜提高了钢铁的耐磨性和耐蚀性。     

铈转化膜在烟气冷凝液中腐蚀行为

通过正交实验得出在铝硅合金表面制备铈转化膜的最佳工艺参数为:Ce(NO3)3为14 g/L;KMnO4为1.5 g/L;K2S2O8为1.0 g/L;NaF为0.8 g/L;转化液pH值为2;室温成膜时间为60 min。SEM、EDS、XRD分析结果表明,铝硅合金表面的Ce-Mn转化膜由基膜和粘附的大小不一的颗粒组成;膜层厚度大约10μm~15μm,主要由Ce和Mn的氧化物、氢氧化物组成;由动电位极化、交流阻抗、浸泡实验等测试结果表明,经Ce-Mn转化膜处理后,自腐蚀电位正移210 mV;腐蚀电流密度降低90%;电荷传递电阻增加一个数量级,具有较高的膜层电阻、较低的膜层电容与双电层电容、较高的弥散指数。     

Chinalco Signed Framework Agreement for Strategic Cooperation with Harbin Municipal Government

正Last month,Chinalco signed framework agreement for strategic cooperation with Harbin Municipal Government in Harbin Xiong Weiping,Chairman of Chinalco,said that based on the strategic deployment to build world top-class mining company with the highest growth potential,Chinalco was now concentrating all efforts on making strategic transition and structural adjustment,strategic cooperation with the local governments where     

Jiangxi Promotes Jiangxi Copper Corporation To Become The World's Most Competitive Mining Company

<正>According to the latest info from Jiangxi Province State-owned Assets Supervision and Administration Commission,Jiangxi Copper Corporation was approved to become the first pilot enterprise for deepening reform.Contents of the pilot work is"Three Self"(self expansion,self decision-making,self     

Journal of Rare Earths Contents List of Vol.32(2014)

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Contributions to Baosteel Technical Research wanted

正Baosteel Technical Research,a quarterly journal,which is issued domestically and abroad,is run and sponsored by Baosteel Group Corporation.Baosteel Technical Research mainly reports the achievements in technological innovation,academic research,new product development and industrial equipment improvement by Baosteel.It will continue to follow up on hot topics and serve the company’s technological development and progress.Its readers include experts in     

Ministry of Industry and Information Technology: No Short Term Solution For Our Country’s Excess Nonferrous Metal Smelting Capacity

【正】According to the Ministry of Industry and Information Technology,the Ministry has released the 2013 Operation Report on China’s Industrial Communication Indu...     

Chinalco Signed Framework Agreement for Strategic Cooperation with Gansu Province

正Recently,Chinalco and Gansu Provincial People’s Government signed"Framework Agreement for Strategic Cooperation on Reform,Restructuring and Transition Development of Chinalco’s Electrolytic Aluminum Enterprises in Gansu",signifying that the strategic cooperation between Chinalco and Gansu Province had made new substantive progress.     

Unavoidable Economic Cycle:30% Of Nonferrous Metal Companies Were Involved In Restructuring

正Owing to continual downturn in real estate and bulk commodity markets,a number of traditional industries in China suffered unfavorable impact in performance.With the progressive disclosure of third quarter report,the no-pleasant-surprise performance of     

Baotou Rare Earth Became the World's Biggest High Performance Magnetic Material Base

正The High Performance Magnetic Material Phase II Project,an industry upgrading project implemented by Inner Mongolia Baotou IronSteel Rare Earth(Group)Hi-tech Co.,Ltd,recently basically finished equipment commissioning,signifying that the enterprise had developed the production capacity of15000 t/a Nd-Fe-B strip casting alloy and 5000t/a Nd-Fe-B magnet,thus becoming the world’s     

Introducing Two Central Enterprises to Integrate Rare Earth Industry,Shandong Rare Earth Group Breaks Surface

正With the signing of"Letter of intention for Propelling Integration of Shandong Rare Earth Enterprises"between Shandong Province Commission Of Economy and Informatization,China IronSteel Research Institute Group("China Steel Institute"),and China Rare MetalsRare Earth Co.,Ltd("China Rare Earth"),the"Shandong Rare Earth Group"jointly set up by the 3 units thus broke surface.On August 9,reporters of the China Economic Herald learned from Shandong Province     

Aluminium Production by Province or City in 2014

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