Studies on electroless Ni-P-Cr_2O_3 and Ni-P-SiO_2 composite coatings

本文对化学镀镍及化学镀镍磷基质中SiO2与Cr2O3的共沉积进行了研究。微粒在不断生长的膜层中共沉积引起了新的化学复合镀层的出现,这些复合镀层许多都具有优异的耐磨及耐蚀性能。通过选取镀层合金/复合微粒/金属基体的组分可改进镀层,获得所需的性能,以满足特别的需求。在对这些复合镀层的应用需求正在迫近与增长的同时,其市场正在迅速扩张。本文开发出了一种合适的复合化学镀镍液,并通过维氏硬度法对化学复合镀镍层进行了表征。采用动电位极化及交流阻抗法测定了镀层的Taber耐磨性能及耐蚀性能。采用SEM及XRD对复合镀层的表面形貌进行了分析。

化学镀镍的渗氢测量(英文)

介绍了一种适用于化学镀镍工艺的渗氢测量方法 ,可用于监控渗氢速度 ,测定氢在金属中的扩散 ,研究氢脆 ,评估腐蚀阻化剂和酸洗中钢铁的吸氢等方面。化学镀应用中经常要使用加速剂 ,本研究的目标物质是化学镀镍的加速剂———硫脲及其衍生物。在这些物质存在下 ,化学镀镍过程中的渗氢行为不同。良好的加速剂可减少氢渗 ,加快金属的覆盖。

Microstructure and crystallographic characteristics of nanocrystalline copper prepared from acetate solutions by electrodeposition technique

Methane sulphonic acid is an alternative electrolyte for conventional sulphuric acid for copper deposition.Theelectrodeposition of copper from eco-friendly acetate-based electrolytes consisting of copper acetate,sodium acetate and methanesulphonic acid was dealt.Thamine hydrochloride(THC),saccharin and4-amino-3-hydroxynaphthalene1-suphonic acid were used asadditives in depositing electrolytes.The cathode current efficiency was calculated using the Faraday’s law.Metal distrbution ratio ofthe solutions was determined using Haring?Blum cell.These additives impact the surface morphology of deposited copper films bydowngrading,the grain size was analyzed by scanning electron microscopy(SEM)and X-ray diffiraction technique.XRD patternacquired for electrodeposited copper film shows polycrystalline and face centered cubic structure(FCC).The crystal size of thecopper film was calculated using the Debye?Scherrer’s equation.The crystal size revealed that deposits produced from additivecontaining electrolytes exhibited the lowest grain size.Texture coefficient analysis studies revealed that all copper film deposits arepolycrystalline and the crystals are preferentially oriented and parallel to the surface.A uniform and pin-hole free surfacemorphology and grain refining were brought about by the additives.

利用旋转圆筒赫尔槽表征氨基磺酸镍电铸液(英文)

赫尔槽实验可以在很宽的电流密度范围内提供电沉积过程的信息,但受到溶液搅拌的限制。旋转圆筒赫尔槽利用旋转圆筒作阴极,消除了常规赫尔槽在搅拌处理的不足。本文利用旋转圆筒赫尔槽,采用不同的电解质浓度和旋转速度评价了氨基酸镍电解质溶液的性能,并测定了溶液的分散能力。

The Inhibitive Effect of para-Amino Benzoic Acid and Its Polymer on Corrosion of Iron in 1 mol/L HC1 Solution

Poly p-aminobenzoic acid has been synthesized by chemical oxidation method. The inhibitive effect of poly p-aminobenzoic acid on iron in 1 mol/L HCI solution was investigated by polarization and electrochemical impedance spectroscopy and compared with that of monomer p-aminobenzoic acid. The effectiveness of poly p-aminobenzoic acid is very high in comparison with that of monomer. The results show that both cathodic and anodic processes were suppressed by p-aminobenzoic acid and poly p-aminobenzoic acid of iron dissolution in 1 mol/L HCI by their adsorption on the iron surface. The inhibition efficiency of both p-aminobenzoic acid and poly p-aminobenzoic acid were found to increase with the inhibitor concentrations. Ultraviolet （UV） reflectance studies of the iron surface after exposure to inhibitor acid show that poly p-aminobenzoic acid is strongly adsorbed on iron surface.

直流、单向脉冲和换向脉冲法制备镍-钴-碳化钨复合镀层的比较(英文)

在醋酸盐镀液体系中采用直流(DC)、单向脉冲电流(PC)和换向脉冲电流(PRC)3种方法制备了Ni-Co-WC复合镀层。采用扫描电镜及电化学阻抗谱(EIS)表征了镀层的微观组织及耐蚀性。结果表明,镀层的微观结构及性能受镀层中WC含量的影响很大。在最佳WC含量的情况下,镀层的显微硬度及耐蚀性都明显提高。与PC和DC法制备的复合镀层相比,PRC法制备的复合镀层具有更致密的表面,更高的显微硬度以及更好的耐蚀性。