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1.
 探讨了泡沫镍制备过程中,聚氨酯泡沫模板上的低温化学镀镍工艺,考察了镀液温度、pH值、主盐与还原剂浓度对沉积速率的影响。得出了适宜的工艺条件:硫酸镍30 g/L、次亚磷酸钠30 g/L、柠檬酸钠10 g/L、氯化铵30 g/L,镀液pH=9.0~9.5、温度45 ℃。在该工艺条件下,化学镀过程稳定,沉积速率可达40 mg/(cm3×h)。化学镀镍后经电镀、热解和还原退火处理制得泡沫镍,其样品呈3维网络状结构,密度为0.74 g/cm3,孔隙率为91.7%。  相似文献   

2.
 采用化学镀工艺在ICF聚苯乙烯靶丸表面包覆了一层磁性的Ni-P合金镀层,并分别用扫描电子显微镜、能谱仪、X射线衍射仪以及振动样品磁强计对其形貌、组成、结构和磁性能进行了表征。结果表明:通过化学镀工艺制备的Ni-P合金镀层厚度约为4 μm,且为非晶结构,并具有一定的磁性;该磁性ICF靶丸可望用来进行磁悬浮实验研究。最后,对聚苯乙烯靶丸表面磁性涂层的制备机理进行了讨论。  相似文献   

3.
 采用化学镀方法对ICF空心玻璃微球靶丸进行处理,使其表面均匀包覆一层磁性Ni-P合金镀层,从而使得ICF玻璃靶丸具有一定的磁性,可望用于进行磁悬浮ICF定位打靶实验研究。用X射线衍射仪、扫描电子显微镜和振动样品磁强计对涂层的组成、结构、形貌及磁性能进行了表征。结果表明:对 ICF玻璃靶丸进行化学镀处理,其球形度、同心度和壁厚均匀性都与化学镀前未发生明显改变,其饱和磁化强度和矫顽力分别为3.883×10-3 A/g和1.046×-3 T。  相似文献   

4.
 采用化学镀工艺在ICF玻璃靶丸表面包覆了一层磁性的Ni-P合金镀层,制备出磁性ICF玻璃靶丸。研究了化学镀主盐质量浓度、还原剂质量浓度、络合剂质量浓度、施镀温度及镀液pH值对沉积速率与镀液稳定性的影响,获得了化学镀制备磁性ICF玻璃靶丸的最佳工艺为:主盐硫酸镍30 g/L,还原剂次亚磷酸钠30 g/L,络合剂柠檬酸钠50 g/L,pH值10,温度(40±2) ℃。  相似文献   

5.
Tetraethoxy silane was used to functionalize the surface of fiber glass (FG) for adsorption with the electroless plated silver shell. The performance of electroless silver plated FG with tetraethoxy silane modification was compared to that of unmodified FG in terms of mechanical and electrical properties. The silane bridge provided more stability for binding with different concentrations of electroless plating silver ions. The characterization was investigated by using field emission scanning electron microscope (FESEM), X-ray diffraction patterns (XRD), energy-dispersion X-ray (EDX), metal microscope (MM) and electric resistance. The Ag coating on TEOS modified FG was more durable than that of unmodified FG in the ball milling test, as confirmed by the data of electric resistance and residue weight. The optimized conditions for producing the Ag coating FG were also investigated. The Ag-Si-FG-3-c product in this study has the lowest electrical resistance of 1.56 × 103 Ω/cm2 and good mechanical stability as exhibited in ball milling tests.  相似文献   

6.
 在预处理芯轴(基体)表面金属的催化作用下,通过镀液可控制的还原反应在芯轴表面不断产生金属Cu的化学沉积,然后刻蚀掉芯轴,经Cu层表面钝化处理而得到空腔Cu靶。对Cu靶的表面形貌、孔隙率、厚度及其均匀性、Cu靶纯度、耐氧化性能等进行了测试与分析,实验结果表明,所测各项数据达到Cu靶ICF应用的性能指标。化学镀方法为制备其它金属或合金空腔靶提供了新的途径。  相似文献   

7.
探讨了泡沫镍制备过程中,聚氨酯泡沫模板上的低温化学镀镍工艺,考察了镀液温度、pH值、主盐与还原剂浓度对沉积速率的影响。得出了适宜的工艺条件:硫酸镍30 g/L、次亚磷酸钠30 g/L、柠檬酸钠10 g/L、氯化铵30 g/L,镀液pH=9.0~9.5、温度45 ℃。在该工艺条件下,化学镀过程稳定,沉积速率可达40 mg/(cm3×h)。化学镀镍后经电镀、热解和还原退火处理制得泡沫镍,其样品呈3维网络状结构,密度为0.74 g/cm3,孔隙率为91.7%。  相似文献   

8.
Electroless nickel plating on APTHS modified wood veneer for EMI shielding   总被引:3,自引:0,他引:3  
A new activation process was developed for electroless plating to prepare wood-based EMI shielding material. Pd(II) was adsorbed on a wood surface modified with γ-aminopropyltrihydroxysilane (APTHS) formed by the hydrolysis of γ-aminopropyltriethoxysilane (APTES). After reduction of Pd(II), electroless plating was successfully initiated and an Ni-P coating was deposited on the wood veneer. The activation process and resulting coating were characterized by XPS, SEM-EDS and XRD. The metal deposition, surface resistivity and electromagnetic shielding effectiveness were measured. XPS analysis proved that Pd(II) was bonded to the amino group of APTHS and was reduced to Pd(0). The Ni-P coating was uniform, compact and continuous, and consisted of 3.39 wt.% phosphorus and 96.61 wt.% nickel. XRD analysis indicated that the coating was crystalline, which is thought to be related to the low phosphorus content. The plated birch veneers exhibited electromagnetic shielding effectiveness greater than 60 dB in the frequency range 10 MHz-1.5 GHz.  相似文献   

9.
Experimental observations are presented of the effect of flow velocity, oxygen concentration, and a thermal radiant flux on the transition from smoldering to flaming in forward smoldering of small samples of polyurethane foam with a gas/solid interface. The experiments are part of a project studying the transition from smoldering to flaming under conditions encountered in spacecraft facilities, i.e., microgravity, low velocity variable oxygen concentration flows. Because the microgravity experiments are planned for the International Space Station, the foam samples had to be limited in size for safety and launch mass reasons. The feasible sample size is too small for smolder to self-propagate because of heat losses to the surroundings. Thus, the smolder propagation and the transition to flaming had to be assisted by reducing heat losses to the surroundings and increasing the oxygen concentration. The experiments are conducted with small parallelepiped samples vertically placed in a wind tunnel. Three of the sample lateral-sides are maintained at elevated temperature, and the fourth side is exposed to an upward flow and a radiant flux. It is found that decreasing the flow velocity and increasing its oxygen concentration, and/or increasing the radiant flux enhances the transition to flaming and reduces the time delay to transition. Limiting external conditions for the transition to flaming are reported for this experimental configuration. The results show that smolder propagation and transition to flaming can occur in relatively small fuel samples if the external conditions are appropriate. The results also indicate that transition to flaming occurs in the char region left behind by the smolder reaction, and it has the characteristics of a gas-phase ignition induced by the smolder reaction, which acts as the source of both gaseous fuel and heat. A simplified energy balance analysis is able to predict the boundaries between the transition/no transition regions.  相似文献   

10.
A modified activation process was developed for electroless Ni-P coating preparation of conductive mica powder. The electroless Ni-P coating process was modified by replacing the conventional sensitization and activation steps only using activation step with a Pd(II)-APTHS activator, which is a complex of Pd(II) ion with a derivate γ-aminopropyltrihydroxysilane (APTHS) from the hydrolysis of γ-aminopropyltriethoxysilane (APTES). The activated reaction progress and resulted Ni-P coating were characterized by XPS, SEM/EDX and TEM. Electroless nickel deposition was successfully initiated by this activation process. This activation process is very simple, and the obtained Ni-P deposits have the advantages of uniformity, continuity and densification. The average specific resistivity for the Ni-P coated mica powder was 4.85 × 10−2 Ω cm.  相似文献   

11.
Electroless deposition of Cu on poly(ethylene terephthalate) (PET) fabric modified with 3-mercaptopropyltriethoxysilane was investigated. Morphology, composition, structure, thermal decomposing behavior of copper coating PET fabric after ultrasonic washing in water for 1 h were characterized by scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis, X-ray photoelectron spectroscopy (XPS), Raman spectrometer, X-ray diffraction (XRD), and thermogravimetric analysis (TG), respectively. Copper plating on modified fabric has good adherence stability and high electric conductivity before and after ultrasonic washing, while copper coating fabric without modification is easily destroyed during the washing process, which leads to the textile changing from conductor to dielectric. As the copper weight on the treated fabric is 28 g/m2, the shielding effectiveness (SE) is more than 54 dB at frequency ranging from 0.01 MHz to 18 GHz.  相似文献   

12.
This work focuses on developing a novel convenient method for electroless copper deposition on glass material. This method is relied on the formation of amino (NH2)-terminated film on the surface of glass substrate, by coating polyethylenimine (PEI) on glass matrix and using epichlorohydrin (ECH) as cross-linking agent. The introduced amino groups can effectively adsorb the palladium, the catalysts which could initiate the subsequent Cu electroless plating, onto the glass substrate surface. Finally, a copper film is formed on the palladium-activated glass substrate through copper electroless plating and the surface-coppered glass material is therefore acquired. X-ray diffraction (XRD), atomic force microscope (AFM), scanning electron microscopy (SEM) images combined with energy diffraction X-ray (EDX) analysis demonstrate the successful copper deposition on the surface of glass substrate.  相似文献   

13.
The electroless NiCoFeP films were deposited on a silicon substrate in a bath containing Ni2+, Co2+, and Fe2+ ions with a concentration ratio of 1:1.9:1.2. These films were characterized by using transmission electron microscope, energy dispersive X-ray spectrometer, and alternating gradient magnetometer for their microstructure, crystal structure, and magnetic properties. The result showed that the film deposited at the initial stage (about 10 s) consists of only one phase with a crystal structure of FCC Ni and a composition about Ni (69 at%), Co (19 at%), Fe (4 at%), and P (7 at%); The film deposited at the latter stage (about 30 s) consists of two phase, one is similar to that of initial stage and the other has crystal structure of HCP Co with a composition about Ni (35 at%), Co (44 at%), Fe (19 at%), and P (2 at%). The saturation magnetization and coercivity of electroless NiCoFeP films vary from 525 to 1546 emu/cm3 [0.68–2.01 T] and from 51.44 to 88.5 Oe [4.09–7.04 kA/m], respectively.  相似文献   

14.
采用化学镀工艺在ICF聚苯乙烯靶丸表面包覆了一层磁性的Ni-P合金镀层,并分别用扫描电子显微镜、能谱仪、X射线衍射仪以及振动样品磁强计对其形貌、组成、结构和磁性能进行了表征。结果表明:通过化学镀工艺制备的Ni-P合金镀层厚度约为4 μm,且为非晶结构,并具有一定的磁性;该磁性ICF靶丸可望用来进行磁悬浮实验研究。最后,对聚苯乙烯靶丸表面磁性涂层的制备机理进行了讨论。  相似文献   

15.
 介绍了在预处理芯轴(聚甲基丙烯酸甲酯)表面采用化学镀的方法制备铜空腔的技术,研究了镀液中硫酸铜含量、甲醛含量,镀液pH值、温度等对化学镀铜沉积速率和溶液稳定性的影响。根据实验确定了适宜的化学镀铜工艺规范:硫酸铜质量浓度10~20 g/L,TART·K·Na质量浓度10~30 g/L,EDTA·2Na质量浓度10~28 g/L,甲醛体积浓度10~25 mL/L,添加剂质量浓度10 mg/L,pH值12~13,温度35~65 ℃。通过该工艺制备出的镀层厚度达到10~25 μm,均匀性达到95%,表面无砂眼、裂纹等缺陷,刻蚀芯轴后空腔能自持。该方法为ICF研究制备金属或合金材料靶提供了新的途径。  相似文献   

16.
Nickel plating graphite nanosheets (Ni/GNs) were prepared by electroless plating method using graphite nanosheets (GNs). Then a novel polymer magnetic composites based on acrylate pressure-sensitive adhesive (acrylate PSA) filled with Ni/GNs were fabricated by solution blend method. The Ni/GNs and acrylate PSA/Ni/GNs composites were characterized by scanning electron microscope (SEM)/energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), vibrating sample magnetometer (VSM) and transmission electron microscope (TEM). All results showed that relatively uniform and compact Ni layer is successfully coated onto GNs under the given conditions, furthermore, Ni/GNs are homogeneously dispersed in acrylate PSA. The VSM results showed that the saturation magnetization of acrylate PSA/Ni/GNs composites increases with an increasing content of Ni/GNs while the coercivity decreases with an increasing content of Ni/GNs. When the content of GNs is 20 wt%, acrylate PSA/Ni/GNs composites exhibites good mechanical properties.  相似文献   

17.
Electroless copper plating on micron-scale acrylate rubber (ACM) microspheres was studied. The core-shell structured Cu-coated ACM microspheres with high conductivity and low density were fabricated by introducing a reaction control method. Via multi-times activating treatment, the acrylate rubber (ACM) microspheres were implanted with more Ag catalytic active centers on the surfaces to promote the formation of coatings. The surface-coating structures and the electrical properties of Cu-coated ACM microspheres were investigated. It was found that the Cu-coated ACM microspheres were a kind of elastic particles. The different coating structures could be produced by controlling the extent of plating reaction. The coated microspheres with different coating structures were conductive, and their volume resistivities decreased remarkably with the increasing of applied pressure and varied with the temperature according to their surface coating structures.  相似文献   

18.
A novel microwave-assisted activation method for electroless plating on PMMA microspheres is presented in this study. When the microwave irradiation was applied during the activation step, the amount of the Pd species adsorbed on PMMA surfaces was much higher than that of sample pretreated with a conventional activation process without microwave irradiation. With this activation method, it was also shown that the adsorbed Pd species with a size of 4-6 nm were uniformly distributed on the surfaces of the PMMA microspheres, thus a smooth and uniform nickel-phosphorus coating on the PMMA microspheres was obtained by subsequent electroless plating. The samples after each step were characterized by XPS, TEM, ICP and SEM.  相似文献   

19.
Patterned gold microstructures on glass or Si wafers have been fabricated by a novel method which is composed of selective electroless plating and microcontact printing. This process may be widely used for the production of fine metal patterns in printed circuits or as a substrate to form patterned SAMs. In addition, these patterned metal microstructures can be readily transferred to adhesive tape surface to fabricate flexible metal microstructure, which may be applied in all-plastic circuit.  相似文献   

20.
ZnO was coated homogeneously with amorphous Ni film by an electroless plating process. After electroless Ni plating, transmission electron microscope (TEM) images and energy dispersive spectrometry spectra (EDS) of ZnO clearly indicated that Ni was coated on the surface of ZnO, the coatings and ZnO contacted enough. X-ray diffraction and high-resolution TEM showed that the Ni film on ZnO was amorphous. Electrochemical performance of Ni-coated ZnO was investigated by the galvanostatic charge/discharge cycling test. Compared to that of uncoated ZnO, the charging–discharging performance of Ni-coated ZnO was obviously improved, e.g. the average discharge capacity of the Ni-coated ZnO increased 71.5% at the stage of stable cycling test.  相似文献   

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