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Process and properties of electroless Ni-W-B amorphous electrical resistance film

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 144-146页

作者： ZHU Xiao-yun guo zhong-cheng XU Rui-dong The Centre of New Materials and Surface Engineering Research and Development Kunming University of Science and Technology Kunming 650093 China The Centre of New Materials and Surface Engineering Research and DevelopmentKunming University of Science and Technology Kunming 650093 China The Centre of New Materials and Surface Engineering Research and DevelopmentKunming University of Science and Technology Kunming 650093 China

The process and properties of electroless plating Ni-W-B alloy have been studied. The results show that the deposits containing W and B are obtained, and the deposition rate of the bath is increased with increase of W content when a certain amount of sodium tungstate solution is added in the Ni-B bath. The Ni-W-B alloy is amorphous as deposition and its resistivity increases directly with the increase of W content in the coating, but decreases gradually with increasing the deposit thickness. XRD and SEM show that the distributions of W and B in the Ni-W-B alloy film are very uniform and dispersed without any segregation.

关键词： electroless Ni-W-B alloy electrical resistance film properties

Effects of pulse current on properties of electrodeposited RE-Ni-W-P-SiC composite coating

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 140-143页

作者： guo zhong-cheng ZHU Xiao-yun XU Rui-dong Center of Materials and Surface Engineering Research and Development Kunming University of Science and Technology Kunming 650093 China Center of Materials and Surface Engineering Research and DevelopmentKunming University of Science and Technology Kunming 650093 China Center of Materials and Surface Engineering Research and DevelopmentKunming University of Science and Technology Kunming 650093 China

Effects of pulse current on properties of electrodeposited RE-Ni-W-P-SiC composite coating were studied. The results show that hardness of the pulse current electrodeposited composite coatings is higher than that of the direct current electrodeposited composite coatings while other parameters are the same. Otherwise, the deposited velocity is higher, and wear resistance and corrosion resistance of the pulse current electrodeposited composite coatings are also improved when the average current density is 10 A/dm2 , pulse frequency is 800 Hz and duty ratio is 1: 5. The hardness of the coating as-deposited is HV500 - 700, and it reaches HV1300 after heat treatment at 400 ℃ for 1 h.

关键词： RE-Ni-W-P-SiC composite coating pulse current electrodeposition properties

Bio-based and Biodegradable Electrospun Fibers Composed of Poly(L-lactide) and Polyamide 4

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Chinese Journal of Polymer Science 2020年第1期38卷 53-62,I0006页

作者： Tao Chen guo-cheng zhong Yuan-Ting Zhang Li-Ming Zhao Yong-Jun Qiu School of Materials Science and Engineering East China University of Science and TechnologyShanghai 200237China Key Laboratory of Bio-based Material Engineering of China National Light Industry Council Shanghai200237China Shanghai Key Laboratory of Advanced Polymeric Materials Shanghai200237China School of Biotechnology East China University of Science and TechnologyShanghai200237China

Novel bio-based and biodegradable block copolymers were synthesized by "click" reaction between poly(L-lactide)(PLLA) and polyamide 4(PA4). Upon tuning the molar mass of PLLA block, the properties of copolymers and electrospun ultrafine fibers were investigated and compared with those of PLLA and PA4 blends. PLLA and PA4 were found incompatible and formed individual crystalline regions, along with reciprocal inhibition in crystallization. Electrospun fibers were highly hydrophobic, even if hydrophilic PA4 was the rich component. The crystallinity of either PLLA or PA4 decreased after electrospinning and PLLA-rich as-spun fibers were almost amorphous. Immersion tests proved that fibers of block copolymers were relatively homogeneous with micro-phase separation between PLLA and PA4. The fibrous structures of copolymers were different from those of the fibers electrospun from blends, for which sheath-core structure induced by macro-phase separation between homopolymers of PLLA and PA4 was confirmed by TEM, EDS, and XPS.

关键词： Poly(L-lactide) Polyamide 4 "Click"reaction Electrospinning Fiber

Study of a New Chromium-Free Conversion Coating Formed on ZnAl Alloy

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材料热处理学报 2004年第05B期25卷 1149-1153页

作者： LONGJin-ming guozhong-cheng HANXia-yun YANGNing FacultyofMaterialsandMetallurgicalEngineering KunmingUniversityofScienceandTechnologyKunmingChina

A new chromium-free conversion film was obtained on surface of a ZnAl alloy by chemical conversion process. Influence of the additives in treating solution containing cerium salt on the corrosion protection of the conversion film formed on zinc alloy was investigated. Corrosion tests and electrochemical measurements in sodium chloride solution were performed . The microstructure and composition of the coatings were examined by means of SEM, EDS and XRD. It was found that the corrosion protection capabilities of the conversion film are markedly increased with the cerium nitride plus additives (hydrogen fluoride acid and an organic inhibitor) treating process. The modified conversion film is an organic/inorganic composite coating and is much more corrosion resistant than the conventional chromate conversion coating and the single cerium conversion coating.

关键词： ZnAl合金铬自由转化涂层稀土盐有机抑制剂防腐蚀

Studies on High Temperature Oxidation of Electrodeposited RE-Ni-W-P-SiC Composite Materials

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材料热处理学报 2004年第05B期25卷 1126-1129页

作者： ZHUXiao-yun XURui-dong guozhong-cheng TheCenterofNewMaterialsandSurfaceEngineeringResearchandDevelopment KunmingUniversityofScienceandTechnologyKunming650093PR.China

The oxidation of the Electrodeposited RE-Ni-W-P-SiC Composite materials at high temperature is investigated. The results show that during high temperature oxidation the relationship between the mass change of pure Ni, Ni-W-P, Ni-W-P-SiC or RE-Ni-W-P-SiC coatings and the oxidation time follows a mixed curve, i.e. it is approximately a linear relationship when the oxidation time is less than 60 mins while it is a power function relationship when the oxidation time is over 60 mins. The order for the oxidation rate of the four coatings is Ni> Ni-W-P> Ni-W-P-SiC>RE-Ni-W-P-SiC. The mass change of Ni-W-P, Ni-W-P-SiC or RE-Ni-W-P-SiC coatings increases exponentially with a rise of oxidation temperature. The high temperature-oxidation resistance of RE-Ni-W-P-SiC composite material is 3-4 times than that of Ni-W-P alloy coating. The cross section morphologies and X-ray diffraction patterns indicate that the high temperature-oxidation resistance of RE-Ni-W-P-SiC composite coating is better than any other coatings.

关键词：高温氧化 RE-Ni-W-P-SiC 复合材料显微结构电镀层

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太阳能电池正极浆料用超细银粉的制备

功能材料 2013年第2期44卷 206-211页

作者：李纪黄惠郭忠诚昆明理工大学冶金与能源工程学院昆明理工恒达科技有限公司

采用液相化学还原法,以聚乙二醇4000为分散剂,用抗坏血酸直接还原硝酸银溶液制备太阳能电池正极浆料用银粉。通过扫描电镜(SEM)、激光粒度分析仪和X射线衍射仪(XRD)等方法分析银粉的形貌、粒度及纯度,研究分散剂用量、抗坏血酸浓度、硝... 详细信息

采用液相化学还原法,以聚乙二醇4000为分散剂,用抗坏血酸直接还原硝酸银溶液制备太阳能电池正极浆料用银粉。通过扫描电镜(SEM)、激光粒度分析仪和X射线衍射仪(XRD)等方法分析银粉的形貌、粒度及纯度,研究分散剂用量、抗坏血酸浓度、硝酸银浓度和溶液pH值等工艺条件对银粉粒度、物相结构及形貌的影响。结果表明,随着分散剂用量的增大,银粉颗粒粒度先减小后趋于稳定。在溶液pH值为4,抗坏血酸浓度和硝酸银浓度分别为2.0和0.5mol/L,聚乙二醇4000与硝酸银的质量比为0.10时,可以制得分散性好、纯度高、面心立方晶系和平均粒度为5.32μm的规则球形银粉。并将所得银粉调制成太阳能电池用浆料,通过丝网印刷在硅片上,使用四探针测试仪测得烧结膜的方阻为4.27mΩ/□,可满足太阳能电池的电性能要求。

关键词：超细银粉化学还原法太阳能电池粒径

超硬铝合金作为阴极在锌电积过程中的电化学行为

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工程科学学报 2016年第6期38卷 767-772页

作者：栗韬黄惠郭忠诚昆明理工大学冶金与能源工程学院昆明650093 昆明理工恒达科技股份有限公司昆明650106

选取商业纯铝和超硬铝作为锌电积阴极,在ZnSO_4-H_2SO_4体系中通过电化学测试研究两种阴极的电化学行为,同时利用扫描电镜观察铝合金上电积锌初期形核,X射线衍射分析锌片结晶取向.研究结果表明:500 A·m^(-2)电流密度下纯铝阴极的析出... 详细信息

选取商业纯铝和超硬铝作为锌电积阴极,在ZnSO_4-H_2SO_4体系中通过电化学测试研究两种阴极的电化学行为,同时利用扫描电镜观察铝合金上电积锌初期形核,X射线衍射分析锌片结晶取向.研究结果表明:500 A·m^(-2)电流密度下纯铝阴极的析出电位和交换电流密度分别为-1.541 V和7.74×10-11A·cm^(-2),超硬铝阴极分别为-1.496 V和6.07×10^(-3)A·cm^(-2).合金元素的添加会增加初期形核位置,提高形核速率,而形核速率的提高在一定程度上抑制卤族元素对阴极的腐蚀.沉积3 h后,锌片结晶取向没有发生变化.超硬铝易发生烧板和鼓泡,电流效率低,只有84.54%;纯铝电流效率达到88.04%,且沉积锌平整、光滑,但阴极板容易被卤族元素腐蚀.

关键词：锌冶金电沉积铝合金阴极电化学行为腐蚀

Anodic behavior and microstructure of Al/Pb-Ag-Co anode during zinc electrowinning

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Journal of Central South University 2014年第1期21卷 83-88页

作者：张永春陈步明杨海涛黄惠郭忠诚 Faculty of Metallurgy and Energy Engineering Kunming University of Science and Technology Kunming Hendera Science and Technology Co.Ltd

In order to study the anodic behavior and microstmctures of A1/Pb-Ag-Co anode during zinc electrowinning, by means of potentiodynamic investigations, scanning electron microscopy （SEM） and X-ray diffraction （XRD） analyses, the mechanism of the anodic processes playing on the surface of A1/Pb-0.8%Ag and A1/Pb-0.75%Ag-0.03%Co anodes prepared by electro-deposition from methyl sulfonic acid bath for zinc electrowinning from model sulphate electrolytes have been measured. On the basis of the cyclic voltammograms obtained, information about the corrosion rate of the composite in PbO2 region has been concluded. The microstructures were also observed by means of SEM and XRD which showed Pb-0.75%Ag-0.03%Co alloy composite coating has uniform and chaotic orientation tetragonal symmetry crystallites of PbSO4, but Pb-0.8%Ag alloy composite coating has well-organized orientation crystallites of PbSO4 concentrated in the certain zones after 24 h of anodic polarization. It is important that Al/Pb-0.75%Ag-0.03%Co anode oxide film consists of non-conductive dense MnO2 and PbSO4 and a, fl-PbO2 penetrated into which, in fact, are the active centers of the oxygen evolution after 24 h of anodic polarization.

关键词： A1/Pb-Ag-Co anode zinc electrowinning potentiodynamic investigation corrosion rate

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电流密度对甲基磺酸盐电沉积亚光锡的影响

材料工程 2012年第4期40卷 76-81页

作者：张郭忠诚龙晋明曹梅昆明理工大学冶金与能源工程学院昆明650093 昆明理工大学材料科学与工程学院昆明650093 昆明理工大学理学院昆明650093

在甲基磺酸盐电镀溶液中进行恒电流电沉积亚光锡镀层实验,考察电流密度对镀液极化性能、阴极过电位、电流效率、沉积速率及镀液分散能力的影响。利用SEM和XRD分析不同电流密度所得锡镀层的表面形貌和结晶取向。结果表明:随着电流密度增... 详细信息

在甲基磺酸盐电镀溶液中进行恒电流电沉积亚光锡镀层实验,考察电流密度对镀液极化性能、阴极过电位、电流效率、沉积速率及镀液分散能力的影响。利用SEM和XRD分析不同电流密度所得锡镀层的表面形貌和结晶取向。结果表明:随着电流密度增大(0.5～***-2),镀液的阴极极化增大,电流效率先增加后降低,沉积速率不断加快,但镀液分散能力有所下降;晶体由"向上生长"模式逐渐转变为"侧向生长"模式,择优取向由(321),(431)晶面转变为(112),(332)晶面;添加剂吸附在晶体表面,降低了被吸附晶面的表面自由能,使这些晶面的生长速率下降,从而改变了镀层择优取向和晶体生长的方式。

关键词：电流密度甲基磺酸盐电沉积亚光锡镀层