硼氢化钠对滑轮用铸钢板化学镀Ni-B合金薄膜性能的影响

在滑轮用铸钢板上化学镀Ni-B合金薄膜,并研究了硼氢化钠的质量浓度对化学镀Ni-B合金薄膜性能的影响。结果表明:适当增加硼氢化钠的质量浓度,有利于增大化学镀Ni-B合金薄膜的厚度及硼的质量分数,从而提高化学镀Ni-B合金薄膜的硬度。当硼氢化钠的质量浓度大于1.2 g/L时,硼氢化钠的水解速率加快及剧烈的析氢反应,导致化学镀Ni-B合金薄膜的厚度及硬度有所降低。当硼氢化钠的质量浓度为1.2 g/L时,化学镀Ni-B合金薄膜表面"胞状"颗粒均匀、致密,摩擦因数和磨损率最低,具有最佳的耐磨性。     

Electroless Ni-B deposition from an emulsified supercritical carbon dioxide bath

The electroless deposition of boron-containing Ni (EN-B) film from a supercritical carbon dioxide (sc-CO₂) bath was introduced. The deposition rate in sc-CO₂ bath was one order of magnitude lower than that at ambient pressure without the presence of sc-CO₂. A more uniform chemical composition of the EN-B film could be obtained if it was deposited in the sc-CO₂ bath. X-ray diffraction analyses revealed that the as-deposited film was amorphous in nature, despite of the deposition condition. Deposition defects such as cracks and voids could be avoided if the deposition was conducted in the sc-CO₂ bath. Crystallization and boride precipitation were found after heat treatment at 400 °C for 1 h. The EN-B film deposited from the sc-CO₂ bath had a higher hardness as compared with that of the normal EN-B coating. A substantial increase in hardness was obtained due to boride precipitation.     

镁合金直接化学镀Ni-B镀层的腐蚀电化学行为研究

  研究了镁合金表面化学镀Ni-B合金的电化学行为，采用电化学动电位扫描极化曲线和交流阻抗研究了Ni-B镀层的腐蚀电化学行为，结果表明，Ni-B镀层在3.5%NaCl溶液中具有优良的耐蚀性能.所得Ni-B镀层的自腐蚀电位在－400 mV左右，相对于基体-1460 mV提高了1000 mV，自腐蚀电流密度小于0.7 μA/cm²，相对于基体28.5 μA/cm²降低了近两个数量级，说明Ni-B镀层能够有效地提高AZ91D 镁合金的耐腐蚀性能，使AZ91D镁合金在35%NaCl溶液腐蚀介质中的腐蚀速度明显降低.电化学交流阻抗测试结果符合极化曲线的测量结果，化学镀Ni B镀层后的AZ91D镁合金在3.5％NaCl溶液中的阻抗值相对于基体提高两个数量级，表现为自腐蚀电流降低，阻抗值相应提高.     

Electroless Ni-B plating on SiO2 with 3-aminopropyl-triethoxysilane as a barrier layer against Cu diffusion for through-Si via interconnections in a 3-dimensional multi-chip package

Electroless Ni-B was plated on SiO₂ as a barrier layer against Cu diffusion for through-Si via (TSV) interconnections in a 3-dimensional multi-chip package. The electroless Ni-B was deposited on the entire area of the SiO₂ side wall of a deep via with vapor phase pre-deposition of 3-aminopropyl-triethoxysilane on the SiO₂. The carrier lifetimes in the Si substrates plated with Ni-B/Cu did not decrease with an increase in annealing temperature up to 400 °C. The absence of degradation of carrier lifetimes indicates that Cu atoms did not diffuse into the Si through the Ni-B. The advantages of electroless Ni-B (good conformal deposition and forming an effective diffusion barrier against Cu) make it useful as a barrier layer for TSV interconnections in a 3-dimensional multi-chip package.     

非晶态Ni-B镀层组织结构与性能研究

对非晶态Ni-B镀层的组织结构和性能进行研究,结果表明:非晶态Ni-B镀层以层片状沉积,表面具有胞状结构。经300°×1h热处理,镀层已经晶化,并析出了细小的Ni_3B相;提高加热温度,Ni_3B粒子明显长大。非晶态Ni-B镀层的镀态硬度为HV_(0.1)632,热处理对其硬度和耐磨性有明显的影响,二者分别在经300℃×1h和500℃×1h热处理后达到峰值。     

镍硼镀层对陶瓷与金属联接的影响

采用自催化镀方法对Ａｌ２Ｏ３陶瓷表面进行３Ｎｉ－Ｂ镀层金属化处理，然后，把金属化的Ａｌ２Ｏ３分别和Ｎｉ，Ｆｅ－Ｎｉ合金组成偶对，进行了固相压力扩散焊，并通过组织分分析对界面区的固相反应进行研究。结果表明，经特殊预处理的９９％Ａｌ２Ｏ３陶瓷，其表面镀层Ｎｉ－Ｂ型基体的结合强度可达２５０ＭＰａ以上，镀层呈非晶态，而热处理可完全晶体化。Ｎｉ－Ｂ／Ｎｉ（Ｆｅ－Ｎｉ）对。界面消失，成分完全均匀；Ａｌ２Ｏ３／     

镧对碳纳米管负载型Ni-B非晶态合金乙炔加氢性能的影响

采用超声辅助的浸渍-还原法制备了N i-B/CNT s及L a改性的N i-B/CNT s非晶态合金催化剂,运用ICP、XPS、TPR、H2-TPD、CO化学吸附法对催化剂进行表征,并研究了催化剂的乙炔选择加氢性能。与N i-B/CNT s相比,添加适量L a提高了活性N i表面积,增强了N i的富电子性,促进了催化剂还原、氢脱附性能,并具有更好的加氢活性,L a的适宜添加量为5%~8%(质量分数)。     

温度对AZ31B镁合金表面化学镀Ni-B合金性能的影响

试验研究了镀液温度对AZ31B镁合金表面化学镀Ni-B合金性能的影响。结果表明:镀液温度对化学镀Ni-B合金的镀速、成分、形貌、耐腐蚀性有很大的影响,当温度为80℃时,镀速较大,镀层均匀、紧凑、细小,耐腐蚀性良好。     

Hydrogen production by aqueous-phase reforming of glycerol over Ni-B catalysts

A Ni-B amorphous alloy catalyst (AP Ni) was prepared and used in an aqueous-phase reforming (APR) of glycerol. Higher stability and higher selectivity towards H₂ were obtained when compared with Raney Ni. After 130 h’ on stream aqueous-phase reforming of glycerol, the amorphous Ni-B catalyst was transformed to hexagonal closed-packed (hcp) Ni crystallites. The high selectivity towards hydrogen and catalytic stability may be due to the formation of hcp Ni crystallites during reaction and the protection of B₂O₃. The AP Ni catalyst was found to be 35-50% more active in terms of the H₂ production rate and 17-31% more selective toward H₂ as compared to Raney Ni. The reforming reaction at different reaction temperature, feedstock concentration, feedstock flow rate and other biomass derivatives i.e., ethylene glycol and sorbitol, were also investigated over AP Ni catalyst.     

改性凹凸棒土负载Ni-B合金催化剂的制备及其顺酐选择加氢制γ-丁内酯反应研究

 以硫酸改性凹凸棒土为催化剂载体，利用化学还原法制备了一系列Ni-B/PAL-X非晶态合金催化剂，并作了XRD、TEM、XPS和BET表征；考察了催化剂制备和反应条件对顺酐选择加氢制γ-丁内酯反应的影响。实验结果表明：Ni-B/PAL-8催化剂上，当反应压力为3MPa、反应温度200℃、反应时间2h时，顺酐的转化率达到了100%，γ-丁内酯的收率达到了97.1%；经过硫酸改性后的凹凸棒土载体的棒状，针状结构以及其较高的比表面积是Ni-B/PAL-8催化剂顺酐选择加氢制γ-丁内酯高活性的主要因素。