影响ABS塑料化学镀Ni-Cu-P合金沉积速度的因素探讨

采用化学镀制备了含Ni53．11％、Cu37．8％、P9．09％的Ni-Cu-P三元合金。研究了铜盐、镍盐及络合剂含量,还原剂, pH和施镀温度对该镀层沉积速度的影响。实验结果表明镀速随硫酸镍浓度、次磷酸钠浓度、施镀温度及镀液pH的升高而增加,随硫酸铜浓度、络合剂浓度的升高而降低。并得出的最佳工艺配方及工艺条件为:3．5 g／L硫酸铜,33 g/L硫酸镍, 24 g/L次磷酸钠,64 g／L柠檬酸钠,20 g／L无水醋酸钠,稳定剂适量,温度80℃,pH 8．00．2。     

酸性化学镀Ni-Cu-P工艺及性能研究

研究了酸性化学镀Ni Cu P镀液的pH值对镀层性能和镀速的影响。采用酸性镀液体系,通过正交实验,确定了化学镀Ni Cu P的工艺配方为:0 3g/LCuSO4·5H2O,25g/LNiSO4·6H2O,30g/L柠檬酸钠,20g/L络合剂,40g/L缓冲剂,25g/LNaH2PO2·H2O,0 16g/L稳定剂,θ80～85℃,pH值5～6,t为2h。通过X射线衍射实验研究了镀层的晶型结构,并对化学镀Ni Cu P镀层与Ni P镀层的极化行为进行了研究。结果表明:所得的化学镀Ni Cu P镀层为非晶态结构;其外观光亮,耐硝酸腐蚀时间大于800s,孔隙率为9级,镀速为8μm/h;Ni Cu P合金镀层比Ni P镀层具有更优异的耐蚀性能。     

铝硅合金上化学沉积Ni-Cu-P合金镀层的工艺及性能研究

研究了铝-硅合金表面化学沉积Ni-Cu-P的工艺条件,探讨了镀液组成对镀速的影响,确定了最佳工艺条件为：p(硫酸镍)为30～40g／L,p(硫酸铜)为0.6～0．8g／L,p(次磷酸钠)为25～30g/L,p(柠檬酸钠)为40～50g／L,p(醋酸铵)为30～35g/L,温度为80℃,pH值为6．0。通过扫描电镜、X-射线衍射法探讨了合金镀层的形貌与结构。测定了镀层硬度和阳极极化曲线,结果表明：以该配方所得的镀层表面平整、光亮;未经热处理的镀层呈非晶态结构,随着热处理温度的升高,镀层的显微硬度先增后降,当温度达到400℃时,镀层结构晶体化,其显微硬度达到最大,为1050HV;镀层在3种介质中的耐蚀性顺序为：硫酸(体积分数为10％)＞氯化钠(质量分数为10％)＞氢氧化钠(质量分数为10％)。     

Electrochemical study of electroless deposition of Fe-P alloys

Fe-P deposits were prepared by electroless deposition and the inducing effect of coupled aluminum on Fe-P deposition was studied. The partial reactions of reducer oxidation and metal ions reduction in electroless deposition Fe-P bath were investigated by electrochemical investigation. In situ mixed potentials of the process for electrolytes with different pH were measured. The plating rate of iron alloys was measured gravimetrically and calculated by the deposition current density. The results show that coupled aluminum induces the Fe-P deposition by shifting the potential negatively and decreasing the polarization resistance of anodic and cathodic reaction. The test of the mixed potential theory was performed by comparison between direct experimental values of the mixed potential and plating rate with those derived theoretically from the current-potential curves for partial reactions. Due to the hydrogen evolution, the plating rate determined by electrochemical measurement is higher than the average plating rate determined from gravimetrical measurements.     

超声波化学镀Ni-Cu-P合金

在有机高分子聚合物薄膜,如投影仪专用胶片上超声波化学镀M—Cu—P合金,研究了镀液各组分浓度、pH值变化对沉积速度的影响：通过扫描电镜(SEM)观测镀层的表面形态及厚度,并用其所附带的能谱(EDS)分析镀层成分,采用透射电镜(TEM)观测镀层中粒子的微观形貌及大小,利用X-射线衍射(XRD)表征镀层的微观结构。结果表明,M—Cu—P合金化学镀层为非晶态合金,光亮、均匀,与基体结合面平整：镀层厚度100μm,镀层颗粒大小在30～40nm,各成分含量分别为77．73％～90．64％Ni,0．38％～5．27％Cu,7．23％～14．30％P。     

Electrochemical investigation of the autocatalytic deposition of Ni-Cu-P alloys

Autocatalytic deposition of Ni-Cu-P alloys (55-65 wt % Ni, 25-35 wt % Cu, 7-10 wt %P) has been carried out. It is shown that the hypophosphite concentration must be higher than a certain threshold to induce the autocatalytic process. The impedance behaviour exemplifies the kinetic evolution: a large capacitive loop with a high-frequency inflection when only chemical displacement occurs and two well-defined capacitive features when the autocatalytic process is achieved. Mutual interactions occur between partial oxidation and reduction reactions which are both depolarized as compared to the separate reactions. In addition, phosphorus incorporation is always reduced when the copper content increases. A pH increase accelerates the plating process though it inhibits the cathodic discharge and reduces the copper content.     

化学镀Ni-Cu-P工艺的研究

采用碱性溶液在纯铜表面化学镀Ni-Cu-P。研究了主盐、还原剂、pH值及温度对镀速的影响,总结了镀速随工艺参数变化的规律及机理。     

镁及镁合金化学镀Ni-Cu-P三元合金工艺

研究了镁及镁合金的化学镀Ni-Cu-P三元合金工艺,通过正交试验获得了最佳的镀覆条件。并对镀层的组织结构及其性能进行了测试,所得的Ni-Cu-P三元非晶态镀层结合力好,具有良好的导电性和耐蚀性能。     

芳纶纤维Ni-P/Ni-Cu-P双层化学镀的结构与形貌

采用化学镀技术,实现了芳纶纤维表面化学镀Ni-P/Ni-Cu-P的金属化处理,利用SEM、EDS和XRD分别对芳纶纤维原始样品、粗化后、施镀后及剥落层的表面形貌、镀层的成分和物相进行了分析比较,并对镀层的形成机制及剥落原因进行了分析研究。结果表明:经过预处理的芳纶纤维比表面积增大,增加了其亲水性和活性;化学镀Ni-P/Ni-Cu-P后,Ni-P镀层中镍含量降低,磷含量增多,纯镍转化为Ni₃P且伴随有少量的铜的出现,整体镀层中Ni、Cu、P的原子比为8.54:3.66:5.59,镀层中以纯Cu、Cu₃P和Ni₃P为主;另外由于镀层中应力分布不均,以及P在Ni-P/Ni-Cu-P相界面的偏聚,削弱了界面的结合强度,使局部拉应力集中,造成了镀层的剥落;且化学镀铜是依靠镍离子的催化作用形成镀层的。     

Electrochemical impedance studies of modified Ni-P and Ni-Cu-P deposits in alkaline medium

Ni-P and Ni-Cu-P deposits were supported over the commercial carbon using the electroless plating technique. The formed samples were characterized by applying SEM, XRD and EDX analyses. An amorphous Ni-P surface was obtained with 73.70 wt% Ni and 11.45 wt% P. The addition of copper to the plating bath reduces the deposited amount of nickel and phosphorus. The electrochemical performance of these deposits has been investigated in 0.1 M KOH solution using electrochemical impedance spectroscopy (EIS) measurements. The effect of pH, deposition time and temperature of the plating bath on the impedance characteristics of the two deposits was studied. It was found that the resistance (R_T) and relative thickness (1/C_T) of the two coatings in 0.1 M KOH solution increase with increasing either pH or deposition time or temperature of the plating bath. Our results indicate that Ni-Cu-P deposit has more corrosion resistance and lower corrosion current density (i_corr) value than Ni-P deposit under different conditions. EIS results were well confirmed by potentiodynamic polarization and cyclic voltammetry techniques.     

LaCl_3对化学沉积Ni-Cu-P合金镀层性能的影响

为提高钢材耐蚀性,采用中温酸性化学沉积的方法,在镀液中添加LaCl_3制备Ni-Cu-P合金镀层,并利用维氏硬度计、扫描电子显微镜、能谱及微取向系统、X-射线衍射仪及Autolab电化学工作站分别对镀层的硬度、微观形貌、成分、结构及耐蚀性检测。结果表明:1)镀层硬度随LaCl_3质量浓度增加先增加后减小;2)随镀液中LaCl_3含量的增加,Ni-Cu-P合金镀层结构由非晶态转变为晶态,在LaCl_3质量浓度为0.10 g/L时,所得镀层的晶胞尺寸较小;3)镀液中LaCl_3质量浓度为0.05~0.15 g/L范围内增加时,测得镀层的腐蚀电流密度有先降低后升高的趋势。     

化学沉积纳米晶Co-P合金及其沉积速率影响因素的研究

化学沉积可得到均匀、致密的纳米晶薄膜,是一种较为理想的纳米晶制备方法。采用正交实验优化了化学沉积纳米晶钴磷合金的工艺配方,研究了正交实验5因素如硫酸钴、柠檬酸三钠、硼酸、次磷酸钠和温度及负载因子、沉积时间对沉积速度的影响。研究获得的优化工艺配方和参数为:0 06～0 12mol/LCoSO4·7H2O,0 40～0 55mol/LNaH2PO2·H2O,0 15～0 3mol/LNa3C6H5O7·2H2O,0 3～0 6mol/LH3BO3,50～80℃,负载因子0 4～0 8dm2/L。     

镁合金化学镀Ni-Cu-P合金耐磨性研究

在AZ91D镁合金上直接化学镀Ni-Cu-P合金,得到了均匀、致密的镀层,有良好的结合力,其耐磨试验结果表明:Ni-Cu-P镀层的磨损量仅为基体的43%。X-射线衍射图表明热处理后,Ni-Cu-P合金镀层结构发生了变化,耐磨性有所提高,其磨损量仅为基体的15%。     

Electrochemical studies on electroless ternary and quaternary Ni-P based alloys

The autocatalytic (electroless) deposition of Ni-P based alloys is a well-known commercial process that has found numerous applications because of their excellent anticorrosive, wear, magnetic, solderable properties, etc. It is a barrier coating, protecting the substrate by sealing it off from the corrosive environments, rather than by sacrificial action. The corrosion resistance varies with the phosphorus content of the deposit: relatively high for a high-phosphorus electroless nickel deposit but low for a low-phosphorus electroless nickel deposit. In the present investigation ternary Ni-W-P alloy films were prepared using alkaline citrate-based bath. Quaternary Ni-W-Cu-P films were deposited by the addition of 3 mM copper ions in ternary Ni-W-P bath. X-ray diffraction (XRD) studies indicated that all the deposits were nanocrystalline, i.e. 1.2, 2.1 and 6.0 nm, respectively, for binary, ternary and quaternary alloys. Corrosion resistance of the films was evaluated in 3.5% sodium chloride solution in non-deaerated and deaerated conditions by potentiodynamic polarization and electrochemical impedance (EIS) methods. Lower corrosion current density values were obtained for the coatings tested in deaerated condition. EIS studies showed that higher charge transfer resistance values were obtained for binary Ni-P coatings compared to ternary or quaternary coatings. For all the coatings a gradual increase in the anodic current density had been observed beyond 740 mV. In deaerated condition all the reported coatings exhibited a narrow passive region and all the values of E_p, E_tp and i_pass were very close showing no major changes in the electrochemical behavior. In the non-deaerated conditions no passivation behavior had been observed for all these coatings.     

化学镀镍磷合金镀速的研究

研究了化学镀镍磷合金中镀液成分及操作条件对金镀层沉积速度的影响。     

化学镀Ni-Cu-P合金镀层耐蚀性研究

采用极化曲线和交流阻抗法,与Ni-P合金镀层对比,研究了化学镀Ni-Cu-P合金镀层在3.5%NaCl水溶液中的电化学行为。极化曲线结果表明,化学镀Ni-Cu-P合金镀层的自腐蚀电流密度(4.037μA/cm2)远远小于Ni-P合金镀层,说明Ni-Cu-P合金镀层的耐蚀性能比Ni-P合金镀层好。在交流阻抗谱图中,化学镀Ni-Cu-P合金镀层在整个浸泡过程中仅出现一个时间常数的单容抗弧,镀层电阻不断的增大,表明镀层有钝化膜不断生成。     

柠檬酸对Ni-P合金化学镀沉积速度和镀层性能的影响

研究了柠檬酸浓度对乙酸盐缓冲体系Ni-P合金化学镀沉积速度、镀层含磷量及其耐蚀性与结构的影响，并对镀层在镀态下和经热处理后的耐蚀性与结构进行了比较。结果表明，随柠檬酸浓度的增加，沉积速度先增加后l牵低，而镀层中磷含量则先降低后增加；镀态时高磷合金为非晶态结构且具有较好的耐蚀性，中磷合金则为非晶 微晶结构，耐蚀性较低，而所有镀层经350℃热处理1h后，结构都转变为晶态，且耐蚀性明显提高。     

钢基体的Ni-P和Ni-Cu-P合金镀层的性能研究

对比了Ni-P合金镀层和Ni-Cu-P合金镀层的耐蚀性及硬度。研究了热处理温度及保温时间对两种镀层耐蚀性的影响。结果表明:与Ni-P合金镀层相比,Ni-Cu-P合金镀层表面更加致密,耐蚀性更好;当热处理温度为200~300℃时,Ni-P合金镀层和Ni-Cu-P合金镀层的硬度均随保温时间的延长而增大;当热处理温度为400℃时,Ni-P合金镀层和Ni-Cu-P合金镀层的硬度均随保温时间的延长先增大后减小。     

Modelisation of Ni-P electroless deposition in ammoniacal solutions

A reaction path for the electroless deposition of Ni-P layers is developed. The steady-state polarisation and impedance responses are calculated. The comparison between the experimental results and the calculation shows the adequacy of the model. The mechanism accounts for most of the experimental features observed for the steady-state and the impedance behaviours and their dependencies with pH, hypophosphite and nickel sulphate concentrations.     

镁合金化学镀Ni-Cu-P,Ni-Ce-P镀层耐蚀性能的研究

在AZ 91D镁合金基体上分别制备三元化学镀Ni-Cu-P,Ni-Ce-P镀层,用失重法将试样分别放入质量分数为3.5%的NaCl溶液和质量分数为5%的醋酸溶液中进行耐蚀性对比实验。结果表明:相对于AZ 91D基体,Ni-Cu-P镀层和Ni-Ce-P镀层在质量分数为5%的醋酸溶液中耐蚀性分别提高了50倍和12.8倍,在质量分数为3.5%的NaCl溶液中分别提高了2.76倍和91.63倍;经封孔和热处理封孔后的耐蚀性均有明显提高。实验表明:在AZ 91D镁合金表面化学沉积Ni-Ce-P镀层的综合耐蚀性能优于化学沉积Ni-Cu-P镀层的。该实验有助于解决镁合金的耐蚀性问题、提高其表面性能和拓宽其应用前景。