镍、磷和空心微珠复合镀层摩擦磨损性能研究

运用化学镀方法,把空心微珠作为第二相加入化学镀镍和磷镀液中,制得以镍、磷和空心微珠为主的复合镀层.X射线分析显示,复合镀层经过热处理后由非晶态变成晶态.复合镀层经过热处理后显微硬度及摩擦学性能提高.复合镀层耐磨性比纯镍和磷镀层提高约30%,抗腐蚀性提高77%.运用SEM和XPS等对复合镀层性能和结构进行分析.     

化学镀Ni-B工艺的研究

介绍了一种稳定性高、沉积速度快的酸性化学镀 Ｎｉ－Ｂ工艺．研究了镀液组成成分及工艺条 件对镀层沉积速度的影响,提出了化学镀Ｎｉ－Ｂ合金的最佳镀液组成和工艺条件,结果表明：该镀 层附着性好,经一定热处理后具有很高硬度、耐磨性和耐蚀性     

Ni-Zn-P三元合金沉积速率的研究

Ni-Zn-P合金具有优良的化学、物理性能,已在工业上广泛应用.但是对Ni-Zn-P合金沉积速率的研究,目前还未见报道.在确定化学镀Ni-Zn-P镀液组成的条件下,研究工艺参数如pH值、温度、主盐浓度、施镀时间和稳定剂对沉积速率的影响,并且用点滴实验法对合金镀层的耐蚀性进行测试.结果表明:在其它条件不变的情况下,控制pH值为9,温度98℃,NiSO4浓度35g/L,施镀2h,并加少量稳定剂,能获得800～1000mg/(dm2·h)的镀速,并且镀层有良好的耐蚀性.     

二氧化硅水溶胶的一锅法制备及超疏水棉织物的构筑

通过一锅法,在碱性体系和表面活性剂存在的条件下,以正丙基三甲氧基硅烷作为前驱体制备出二氧化硅水溶胶,再用γ-(2,3-环氧丙氧)丙基三甲氧基硅烷和十六烷基三甲氧基硅烷一锅改性,获得了改性二氧化硅水溶胶.经过传统的浸轧烘工艺,将其应用于棉织物上制备超疏水棉织物.用扫描电子显微镜观察棉织物的表面形貌,用OCA 20型视频光学接触角测量仪测试织物表面的润湿性能,用耐洗色牢度测试仪测试织物的疏水持久性.结果表明,改性织物表面的水滴接触角为160°,并且其超疏水性能可以耐10次家庭洗涤.     

聚丙烯酸模板制备PAA/PbCrO_4复合纳米颗粒

以低分子量聚丙烯酸(PAA)为高分子模板构建自组装体系,合成核-壳结构的PAA/PbCrO4纳米颗粒.通过TEM、XRD、FT-IR、UV-vis、荧光光谱等表征手段对产物的结构、形貌与光学性能进行研究.结果表明:PAA通过羧基与Pb2+的配位作用包覆在PbCrO4纳米颗粒表面,形成核-壳结构,内核PbCrO4尺寸为50~100 nm,为单斜晶系;外壳PAA层厚20 nm.与普通PbCrO4体相材料相比,产物在829~854 cm-1红外吸收峰变宽,紫外与荧光光谱产生了"蓝移",表现出纳米粒子所具有的特殊光学现象.     

硅藻土碳热还原法制备SiC

以硅藻土和活性碳为原料,采用碳热还原法合成SiC粉体。研究了加热温度、保温时间、配碳量和催化剂量对产物产率的影响,并初步探讨了SiC粉体的合成过程机理。结果表明,合成产物主要晶相为β-SiC,优化工艺条件下产物粉体中SiC的含量最高可达92.85%。     

稀土元素在化学镀Ni—P中作用的研究

在确定化学镀Ni-P溶液配方的基础上,添加单一轻稀土离子La^3 ,Ce^3 及二元混合轻稀土,并测量了钢铁试样在化学镀Ni-P合金的基础镀液、添加稀土的化学镀Ni-P合金镀液中的极化曲线,根据极化曲线分析了以上两种镀液中,稀土元素对腐蚀电流、反应沉积速度及表面状态的影响,研究结果稀土元素能够降低化学镀Ni-P中腐蚀速率、加快反应沉积速度、提高化学镀Ni-P镀层的耐蚀性。     

化学沉积法制备Ni-P-SiC复合镀层的研究

研究了在碳钢基材表面进行化学沉积Ni-P-SiC复合镀层的工艺和条件,对镀层的成分进行了扫描分析,对镀层的金相组织进行了观察分析;结果表明SiC硬质纳米粒子嵌入,使Ni-P合金基质产生沉淀强化,使镀层硬度增加.通过对磨实验和腐蚀实验证明,复合镀层可使碳钢零件耐磨性能提高3倍,可使碳钢零件耐蚀性能提高4倍,有效地延长了钢铁零件的使用寿命.     

Anode oxidation of HCHO in THPED-containing electroless copper plating solution

The electrochemical mechanism of anode oxidation of HCHO in electroless copper plating solution with N, N, N', N'-tetrakis(2-hydroxypropyl)ethylenediamine (THPED) was investigated by measuring cyclic voltammetry curves and anodic polarization curves. Three different oxidation peaks occur at the potentials of-0.62V (Peak 1), -0.40V (Peak 2) and -0.17V (Peak 3) in the anode oxidation process of THPED-containing solution. The reaction at Peak 1, a main oxidation reaction, is the irreversible reaction of adsorbed HCHO with hydrogen evolution. The reaction at Peak 2, a secondary oxidation reaction, is the quasi-reversible reaction of adsorbed HCHO without hydrogen evolution. The reaction at Peak 3 is the irreversible oxidation of anode copper. The current density of Peak 1 increases gradually, that of Peak 2 remains constant and that of Peak 3 decreases with the increase of HCHO concentration. The current density of Peak 3 increases with the increase of THPED concentration and the complexation of THPED promotes the dissolution of anode copper.     

Preparation of copper-coated fine molybdenum powders with electroless technique

The molybdenum powders with average particle size of 3 μm were coated with copper by electroless plating. The influence of pretreatment,solution composition and plating conditions on electroless copper plating was studied. The copper-coated molybdenum powders were examined by SEM and XRD. Results indicate that a series of optimization methods is used to add activated sites before electroless copper plating. Taking TEA and EDTA as chief and assistant complex agents respectively,2,2’-bipyridyl and PEG as double stabilizers,the Mo powders are coated with copper successfully with little Cu2O contained,at the same time,Mo-Cu composite powders with copper content of 15-85 wt% can be obtained. The optimal values of pH,temperature and HCHO concentration are 12-13,60-65 ℃ and 22-26 mL/L,respectively.     

化学沉淀法处理化学镀镍废水的数学模型及应用

采用二次回归正交旋转组合设计法，研究化学沉淀法对低浓度化学镀镍废水中镍的处理效果，得到也反应温度、石灰乳投加量及反应时间与废水中剩余镍之间关系的数学模型。实验结果和模型分析表明，适当提高反应温度、石灰乳投加量及反应时间，有利于降低废水中镍的浓度，且三个因素之间存在交互作用。模型预测结果显示，当石灰乳投加量达到7mL/50mL废水时，在高于75℃的反应温度，且大于90min的反应时间的组合试验条件下，该废水中镍的浓度降至1．0mg/L以下，模型预测结果和实验结果均表明，所用方法可以使废水中的镍实现达标排放。     

Synthesis,structural characterization and hydrogen storage of nickel-containing mesoporous MCM-48 by electroless plating

Hydrogen is a promising fuel for it is clean, highly abundant and non-toxic, but on-board storage of hydrogen is still a challenge. So it is imperative to have an efficient method of hydrogen storage. The mesoporous MCM-48 especially the nickel-containing MCM-48 has great potential in hydrogen storage. MCM- 48 was prepared by hydrothermal synthesis. Then electroless plating technology was used to deposit Ni on the surface of MCM-48 under ultrasonic environment. Powder X-ray diffraction (XRD), transmission electron microscopy (TEM), and N₂ adsorption-desorption were employed to investigate the pore structure properties. The results showed that all the samples had Ia3d cubic structure and pore channels were highly ordered. Hydrogen adsorption studies showed that the MCM-48 after nickel plating adsorbed nearly twice the amount of hydrogen than pure MCM-48 at 2.0 MPa, 263 K. So we believe that a small amount of Ni can improve the capacity of hydrogen adsorption of MCM-48 efficiently.     

化学镀镍溶液中络合剂对镀速影响的研究

本文研究了化学镀Ni P合金镀液中络合剂对沉积速度的影响 ,结果表明不同络合剂对镀速的影响各不相同 ,本实验研究出的 3 L复合络合剂 ,它的加入使镀液稳定而镀速较高 .     

钡铁氧体表面化学镀Ni-P合金的制备及性能

为提高钡铁氧体的吸波性能,以钡铁氧体为芯材,采用化学镀的方法制备表面包覆Ni-P镀层的钡铁氧体复合粒子.并利用XRD、SEM、EDS及矢量网络分析仪对其晶体结构、表面形貌、成分、电磁吸收性能进行分析.结果表明:钡铁氧体表面包覆完整的Ni-P合金镀层,化学镀工艺显著改善材料的电磁性能,并提高材料对电磁波的吸收能力,镀后复合粒子在2～18GHz频段内,最大反射率为-24.3dB,大于-10dB的吸收频带宽约2.8GHz.     

长寿高稳定性化学镀镍磷合金工艺研究

采用正交试验法研究了主盐，还原剂，络合剂，稳定剂以及温度对镀层和溶液性能的影响，从而得到了一种长寿命，高稳定性的化学镀镍磷合金工艺，该工艺所得镀层磷含量高，沉积速度快、镀液使用寿命长，并已在实际生产中加以应用。     

金刚石化学镀Ni—W—P金属薄膜研究

选择了适宜的化学镀预处理工艺,确定了化学镀Ni-W-P的合理配方和工艺参数,采用SEM、XRD等检测方法,对化学镀及热处理后金刚石表面形成的金属溥膜进行了分析.结果表明:经化学镀后金刚石表面形成了较致密的金属薄膜,抗压强度提高且最大幅度可达到27.14%.对金刚石化学镀后再经过850℃热处理的XRD检测,证明金刚石表面与薄膜之间已形成碳化物WC,此时金刚石抗压强度比未镀覆时提高了约16.28%.     

Sol—gel法制备铌酸钠钾粉体的研究

以自制氢氧化铌作为铌源,草酸作为螯合剂,以酒石酸钾钠替代碳酸钠和碳酸钾作为钾源和钠源,乙二醇作为酯化剂,采用sol—gel法制备了铌酸钠钾（简称KNN）粉体。使用IR和TG／DSC对干凝胶的成分及溶胶形成过程中的机理进行了研究,使用XRD和SEM对制备的纳米粉体的晶型和形貌进行了表征和观察,研究了预烧温度对于KNN粉体结构和形貌的影响,并解释了产生这些变化的原因。     

Fabrication of micro-flow channels on graphite composite bipolar plates using microplaning

A new method of manufacturing micro-flow channels on graphite composite bipolar plate(GCBPP) microplaning using specially designed multi-tooth tool is proposed. In this method, several or even dozens of parallel micro-flow channels ranging from 100 μm to 500 μm in width can be produced simultaneously. But, edge chippings easily occur on the rib surface of GCBPP during microplaning due to brittleness of graphite composites. Experimental results show that edge chippings result in the increase of contact resistance between bipolar plate and carbon paper at low compaction force. While the edge chippings scarcely exert influence on the contact resistance at high compaction force. Contrary to conventional view, the edge chippings can significantly improve performance of microfuel cell and big edge chippings outperform small edge chippings. In addition, the influence of technical parameters on edge chippings was investigated in order to obtain big, but not oversized edge chippings.