Ni-P合金化学镀非晶态合金的耐蚀性研究

研究了化学镀非晶态Ni-P合金的耐蚀性及耐蚀机理,证明了非晶态Ni-P合金化学镀镀层具有良好的耐蚀性能。     

溶液温度对铝合金化学镀Ni-W-P三元合金的影响

在化学镀中镀液的温度不仅影响施镀过程的沉积速度,而且还将直接影响镀层成分及镀层性能。通过X射线衍射（XRD）、扫描电（SEM）等测试手段着重研究了溶液温度对化学镀Ni—W—P镀层微观组织、相组成、镀速及硬度的影响。结果表明：温度为85℃时,镀层已完全覆盖基体,表面由胞状颗粒组成,大小比较均匀,颗粒直径平均为7μm左右,无明显的缺陷,W的含量高达9．60g,镀态下的硬度高达HV610左右,镀速为11μm／h。     

化学镀Ni—Fe合金的研究

研究了由ＮｉＳＯ４．６Ｈ２Ｏ、ＦｅＳＯ４．７Ｈ２Ｏ柠檬盐及稳定剂等组成的镀液，用化学法施镀Ｎｉ－Ｆｅ合金时，镀液的酸度，温度和铁盐的浓度等因素对镀层沉积速度及镀层组分含量的影响。     

化学镀Ni-P合金耐蚀性的研究

化学镀Ni-P合金在某些介质中具有高的热力学稳定性和钝化行为,耐蚀性好,尤其是非晶态镀层耐蚀性更佳。但是,表面出现胞状结构,由于P含量分布不均,导致耐蚀性下降,P含量沿镀层厚度方向的梯度分布易形成针状蚀孔,引起镀层早期失效。     

AlN陶瓷表面化学镀Ni—P合金的研究

在ＡｌＮ陶瓷上化学镀Ｎｉ－Ｐ合金,使其表面金属化,通过对镀液配方和施镀条件的研究,不仅使得镀层与基体之间附着良好,同时镀层沉积速度有所提高,节约了生产成本。     

化学镀Ni—W—P合金研究

在化学镀Ｎｉ－Ｐ合金的基础上,添加钨酸盐获得Ｎｉ－Ｗ－Ｐ镀层。研究了各工艺参数对镀层成分,镀层性能的影响,并利用Ｘ射线衍射分析了热处理对镀层结构和性能的影响。     

TL—6—2化学镀Ni—P合金工艺研究

通过试验研究，选择出了合理的化学镀Ｎｉ－Ｐ合金工艺，配方与施镀工艺。该镀液性能稳定，便于施镀，调整，使用寿命可达６个周期。该工艺取材于工业级原料，成本低，适于工业生产应用。     

石墨化学镀Ni—P合金的结构及耐蚀性研究

采用扫描电子显微镜、X射线衍射及阳极极化曲线测定等方法,对石墨化学镀Ni-P合金的组织结构及耐蚀性进行了研究.结果表明,该镀层在磷含量大于8%时为非晶态结构;加热到300℃时转变为晶态结构;其表面形貌与普通碳钢Ni-P合金层的表面形貌相同.在不同pH值且含有级离子的介质中均有钝化现象,镀层结合力极强.因此该镀层具有很好的耐蚀性.     

化学镀Ni-P和Ni-Cu-P合金耐蚀性研究

研究了硫酸铜加入量对化学镀Ni-Cu-P合金的镀层成分、组织及热稳定性影响,用中性盐雾实验和在20%H2SO4+20 g/LAl2O3溶液中的冲刷腐蚀实验研究了Ni-P与Ni-Cu-P合金的耐蚀性和耐冲刷腐蚀性能.结果表明,Ni-Cu-P合金镀层具有比Ni-P合金镀层更好的热稳定性、耐蚀性和耐冲刷腐蚀性能.     

TL-4化学镀Ni-P合金在水田机械上的应用

水田机械的关键件，如水稻插秧机的移箱轴和推身杆等，均要求部件表面耐腐蚀抗磨损、有效高的硬度，特别是水稻施肥机的施肥轴是合浸在化肥中进行放置工作的，要求耐蚀非常严格。经采用ＴＬ－４化学镀Ｎi－Ｐ合金工艺对部件进行表面处理达到抗磨耐腐蚀和硬度要求，该工艺沉积速度快、镀液稳定，且施镀条件宽松、取材方便、成本低。镀层中磷含量在１２％左右，其结构为非晶态合金。镀层致密、光洁，达到产品的技术要求。     

激光处理化学沉积Ni-P/Ni-W-P双镀层的显微组织及性能特征(英文)

采用SEM/EDX及XRD定量分析技术研究了化学沉积Ni-P/Ni-W-P双镀层激光晶化前、后的组织特征,并通过表面和截面的硬度测量以及干摩擦磨损实验评估了双镀层的硬度及耐磨性。结果表明,在两种不同的镀液中连续沉积可以制备出Ni-P/Ni-W-P双合金镀层。激光晶化处理后,化学沉积Ni-P/Ni-W-P双镀层表现出外层NiWP比内层NiP更高的晶化程度及更大的晶粒尺寸,但外层具有更高的硬度。激光处理的双镀层在给定的加工条件下,其耐磨性优于镀态镀层的。激光处理可直接在空气中进行而不需要氩气保护,这为工业化应用提供了可能性。     

金刚石表面化学镀Ni-W-P层组织与性能研究

金刚石工具应用时金刚石颗粒的脱落现象比较严重,影响了工具寿命,而金刚石表面镀覆技术是解决这一问题的主要方法.实验研究了化学镀预处理的工艺参数,确定了化学镀Ni-W-P的合理配方.采用SEM、XRD等检测方法,对化学镀及热处理后金刚石表面的镀覆层进行了成分、显微组织、相结构和性能分析.结果表明,经化学镀后金刚石表面能形成较致密的镀覆层,抗压强度提高,最大幅度可达到27.1%.经过850℃热处理,金刚石表面与镀层之间形成了WC碳化物,化学镀再经热处理后金刚石的抗压强度会降低,要比未镀覆和化学镀的金刚石抗压强度分别降低了43.3%和27.2%.化学镀所形成的镀层对金刚石表面有保护作用,使金刚石的耐热蚀性增强.     

Ni-P/Ni-W-P双层化学镀的研究

用双层化学镀工艺取代传统的单层化学镀工艺，得到的Ni-P/Ni-W-P镀层比Ni-W-P镀层更均匀，细致；同时有着更好的硬度，耐磨性和耐蚀性能。     

化学沉积Ni-P/Ni-W-P合金的热处理晶化及磨损行为

用XRD定量法分析了W的共沉积对Ni-P基合金镀层热处理晶化程度、晶粒尺寸的影响,通过镀层硬度测试、干摩擦条件下的磨损实验以及SEM形貌观察研究了镀层的磨损行为.结果表明:W的共沉积提高了镀态和热处理的Ni-W-P镀层的晶化程度,加速Ni相的晶化过程,提高了Ni3P相的晶化反应温度,并使Ni-W-P镀层硬度大于Ni-P镀层的硬度.非晶态Ni-9.27%P镀层晶化前后的磨损行为主要表现为粘着磨损;当P含量与其相同(相近)时,W的加入不改变Ni-5.13%W-9.32%P合金在镀态及低温热处理时的粘着磨损行为,但对高温(600 ℃以上)热处理镀层起主导作用的磨损形式为微切削磨损机制.     

Deposition of electroless Ni-P/Ni-W-P duplex coatings on AZ91D magnesium alloy

The electroless Ni-P/Ni-W-P duplex coatings were deposited directly on AZ91D magnesium alloy by an acid-sulfate nickel bath.Nickel sulphate and sodium tungstate were used as metal ion sources and sodium hypophosphite was used as reducing agent.The coating was characterized for its structure,morphologies,microhardness and corrosion properties.The presence of dense and coarse nodules in the duplex coatings was observed by SEM and EDS.Tungsten content in Ni-P/Ni-W-P alloy is about 0.65%(mass fraction) and t...     

AZ31镁合金“两步法”化学镀Ni -P合金组织及性能研究

研究了AZ31镁合金表面的“两步法”化学镀Ni -P工艺(TSENP).结果表明:在AZ31镁合金表面直接中性化学键8min后可以实现以硫酸镍为主盐的第二步化学镀Ni -P合金,镀层的表面光亮、均匀、致密、无明显缺陷,含磷质量分数为11.42％,表面硬度比AZ31镁合金基体有了很大的提高,与基底的结合力好,并具有优良的耐蚀性能.     

镍—磷合金化学镀镀层成分及时效处理温度对镀层组织性能的影响

用化学镀方法在模具材料表面沉积－层镍－磷合金镀层,通过改变镀层的磷含量、镀后时效处理温度、时效处理时间等参数,用扫描电镜观察镀层组织形貌及用维氏硬度计测定共硬度变化规律,从而得到出了最恰当的时效处理工艺及最佳磷含量。     

The effect of processing gas on corrosion performance of electroless Ni-W-P coatings treated by laser

An investigation of the microstructural and corrosion characteristics of electroless Ni-5.5 W-6.5P coatings on steel substrates after laser treatment in argon and air is presented. The microstructural characteristics of the coatings, in terms of crystallisation, grain size, microstrain, porosity as well as surface chemistry, were examined using quantitative X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Electrochemical tests, using potentiodynamic polarisation in 0.5 M H₂SO₄ solution and electrochemical impedances spectroscopy (EIS) in 3.5% NaCl solution, were undertaken to evaluate the corrosion behaviour of the coatings. The results indicated that the laser-treated coatings consisted of nanocrystalline Ni and Ni₃P phases, along with retained amorphous phase; further, the dimensions of the Ni crystallites were larger than those of Ni₃P. The laser-treated coating in argon revealed the presence of submicron scale porosity, while no porosity was evident in the coating surface treated by laser in air. The uniform corrosion revealed in 0.5 M H₂SO₄ solution is mainly determined by the microstructural characteristics of the coating. Pitting corrosion in 3.5% NaCl solution depended on the amount of porosity on the surface. The laser-treated coating in air exhibited better corrosion resistance in both acidic and chloride environments than that laser-treated in argon.     

Surface morphology and structure of Ni-P, Ni-P-ZrO2, Ni-W-P, Ni-W-P-ZrO2 coatings deposited by electroless method

Electroless binary Ni-P and ternary Ni-W-P alloy coatings and electroless composite (Ni-P-ZrO₂ and Ni-P-W-ZrO₂) nickel coatings were deposited. Baths with aminoacetic acid as the complexing agent were used. ICP measurements showed that the P content depending on the type of coating is in a range of 4.7-6.3 wt.% (at pH = 6, t = 75 °C). The tungsten content is around 1-2 wt.%. SEM examinations show that the electroless Ni-P coating has the most fine-grained structure. Grains in the form of microspheroids 20 μm in size are characteristic of the Ni-P-ZrO₂ coating. X-ray diffraction patterns show that for all the obtained coatings peak Ni(111) located around 2θ = 44° is the most intensive. After the coatings are heat treated at 400 °C for 1 h the peak becomes even sharper. The heat treatment results in a nearly double increase in crystallite size. The quaternary coatings' abrasion resistance is determined by the second-phase (ZrO₂) particles present in them.     

Peculiarities of electroless deposition of Ni-W-P alloy on aluminum

A method of producing compact Ni-W-P films on aluminum from citrate-hypophosphite solution containing glycine as a ligand is proposed. The deposition rate and elemental and phase compositions of Ni-W-P films are shown to depend on the nature of the substrate. It is found that tungstate ions are reduced by hydrogen, which is formed either under catalytic oxidation of hypophosphite ions or upon dissolution of the substrate metal (aluminum) accompanied by hydrogen evolution from water.