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1.
重点介绍了在电镀金刚石环型钻头表面进行化学复合镀Ni-P-SiC层的一般工艺过程,并对由该种方法制造的钻头进行了钻削试验和分析,提出了有关该类钻头在制造中几点值得注意的问题;表明适当地镀复Ni-P-SiC层可以提高该钻头的使用寿命. 相似文献
2.
用稳态极化法研究了Cu-Ni合金阴极在对氨基苯酚电解过程中的有关性能。研究表明,在PAP电合成体系中,不同Cu/Ni比的合金阴极具有不同的交换电流密度i^0,且随着镀液中Cu浓度的增大,i^0的大小呈正态分布,其中Cu-30镀液试片的i^0电大 相似文献
3.
本文研究了电刷镀Ni—P合金镀层的制备工艺、配方试验,测定了镀层的结合强度、耐蚀性等性能,并就电刷镀Ni—P合金镀层的耐腐蚀机理进行了探讨。 相似文献
4.
用稳态极化法研究了Cu—Ni合金阴极在对氨基苯酚(PAP)电解过程中的有关性能。研究表明,在PAP电合成体系中,不同Cu/Ni比的合金阴极具有不同的交换电流密度i°,且随着镀液中Cu(Ⅱ)浓度的增大,i°的大小呈正态分布,其中Cu-30镀液试片的i°最大。与常规所用的Cu、Cu/Hg、Ni、蒙乃尔合金电极相比,Cu-30试片的性能最佳,这与表观活化能所测结果相一致。 相似文献
5.
研究了铝及铝合金表面化学镀Ni-P合金的预处理,镀液配方及镀后热处理。经除油,除洗两道工序处理后,在铝及铝合金表面上直接进行酸性化学镀Ni-P合金,镀速最快可达到 32.5μm/h镀层光亮美现。 相似文献
6.
研究了旋转园盘电极上脉冲电流电解时的传质过程,建立了脉冲电流电解时传质的双扩散层模型,得到了描述传质过程的扩散方程。并利用混合变量分离、延拓等教学方法解得了旋转园盘电极脉冲电流电解传质过程中反应粒子浓度变化的广义表达式,结果满意。 相似文献
7.
本文研究了超声波对化学镀Ni-P非晶态合金的镀速,磷含量,显微硬度及孔隙率的影响.结果表明:超声波可显著地提高化学镀Ni-P合金的镀速,降低合金中磷含量,提高镀层的显微硬度,明显地降低镀层的孔隙率. 相似文献
8.
介绍了一种稳定性高、沉积速度较快的酸性化学镀Ni-P合金工艺.讨论了镀液组成及工艺条件对镀层沉积速度的影响,提出了化学镀Ni-P合金的最佳镀液组成和工艺条件. 相似文献
9.
超声波对化学镀Ni—P非晶态合金性能的影响 总被引:8,自引:0,他引:8
本文研究了超声波对化学镀Ni-P非晶态合金的镀速,磷含量,显微硬度及孔隙率的影响,结果表明:超声波可显著地提高化学Ni-P合金的镀速,降低合金中磷含量,提高镀层的显微硬度,明显地降低镀层的孔隙率。 相似文献
10.
周期换向脉冲电镀参数对Ni—Fe合金镀层成分影响的研究 总被引:1,自引:0,他引:1
采用周期换向脉冲电流(PR)在铁基体上进行了NiFe合金镀的研究。在不改变槽液条件下,改变脉冲参数可获得Ni/Fe比不同的合金镀层,以满足使用要求。讨论了脉冲电镀参数对合金镀层成分影响的规律和双脉冲电镀的一些特性。 相似文献
11.
A simple and low-cost electroless deposition technique is used to prepare nickel-doped carbon nanotubes under different doping conditions, and to explore the influence of different nickel doped samples on the electrical contact properties of carbon nanotubes. First, the original carbon nanotubes are subjected to mixed acid oxidation, sensitization and activation treatment. Subsequently, the nickel chloride hexahydrate is used as the main salt and dimethylamine borane is used as the reducing agent to prepare the electroless deposition solution. And then, the prepared carbon nanotube dispersion is dropped into the electroless deposition solution to obtain the sample of nickel-doped carbon nanotubes. Morphological characterization indicates that the nanoparticles with different particle sizes and doping amounts could be doped on the surface of carbon nanotubes under different deposition conditions. The X-ray energy spectrum shows that the main component of the doped nanoparticles is nickel, and the further X-ray photoelectron spectroscopy reveals the constituent valence state of nickel. However, the Raman spectra indicate that the doping type of nickel-doped carbon nanotubes by this deposition method is the P-type. Finally, the electrical contact performance test results show that the electrical contact properties between gold electrodes and nickel-doped carbon nanotubes with different particle sizes and doping contents are different, but that all of them can be improved to a certain extent. According to the order of nanoparticles with a small particle size and a moderate amount, those with a moderate particle size and a moderate amount, and those with a large particle size and a large amount in the nickel-doped sample, the average value of the contact resistance decreases by 32.70%, 71.63% and 49.33%, respectively. 相似文献
12.
InvestigationofInitialStageofElectrolessNickelDepositiononCarbonSteelWUYiyongHUXyinguoWANGYongqianYAOMei(吴宜勇,胡信国,王永前,姚枚)(Dept... 相似文献
13.
精选镁合金化学镀的前处理工艺和镀镍液配方,根据该工艺得到的镀层试验检测表明:该合金具有耐腐蚀性强、硬度高、结构致密、光泽性好,且有一定延展性;并通过实验比较了4种添加剂对镁合金化学镀镀速及镀液稳定性的影响,实验结果表明,钇和铕对镀液的稳定性影响较大,氟化铵和碳酸钠对镀速的影响较为显著,尤其是添加的Y3 浓度为0.02 g/L时,镀液的稳定性提高最多,而碳酸钠在19 g/L左右时加速作用最为明显.文中并分析了它们的影响机理. 相似文献
14.
A technology for electroless Ni-P deposition on AZ91D from a low cost plating bath containing sulfate nickel was proposed. The seal pretreatment was employed before the electroless Ni-P deposition for the sake of occluding the micro holes of the cast magnesium alloy and interdicting the bubble formation in the Ni-P coating during plating process. And pickling pretreatment can provide a better adhesion between the Ni-P deposition and AZ91D substrate. The deposition speed of the Ni-P coating is 29 μm/h. The technology is employed to AZ91D magnesium alloy automobile parts and can provide high hardness and high wear-resistant. The weight losses of Ni-P plated and heat-treated Ni-P plated magnesium alloy specimen are only about 1/6 and 1/10 that of bare magnesium alloy specimen after 10 min abrasion wear, respectively. The hardness of the electroless Ni-P plated brake pedal support brackets is 674.1 VHN and 935.7 VHN after 2 hours heat treatments at 180 C. The adhesion of Ni-P coatings on magnesium alloy substrates meets the demands of ISO Standards 2819. The technology is environment friendly and cannot cause hazard to environment because of absence of chromate in the whole process. 相似文献
15.
在镁合金AZ91D化学沉积了镍涂层,研究了非铬化预处理及表面活性物质对涂层腐蚀特性的影响。通过盐水试验(1mol/L HCl)和电化学极化试验(3.5%NaCl)检测了腐蚀性能。试验表明:化镀镍溶液中添加的表面活性剂可提高镁合金镍涂层上的抗腐蚀能力。此外,表面平整均匀的纳米和非晶相涂层提高了其抗腐蚀能力。极化试验表明,其腐蚀电位向正方转移,且腐蚀电流密度减低。浸泡试验和电化学极化试验都表明阳离子表面活化剂具有更好的提高抗腐蚀性能的作用。 相似文献
16.
采用化学镀法在化学纤维布表面覆盖均匀镍层,通过热处理去除基体后获得中空镍纤维管;将其置于化学气相沉积装置中,通过调整合适的氢气和甲烷流量比及气压条件制备了以中空微米镍纤维管为主体结构、碳纳米纤维(CNF)以及金属管体结构为存储介质的碳纳米纤维/镍管复合纤维材料.运用扫描电子显微镜(SEM)分析中空镍纤维及复合纤维管表面形貌,x射线衍射(XRD)对复合纤维管晶相组成进行表征.结果表明,利用模版法制备出的中空镍纤维管孔径在10μm左右,管壁厚约0.5μm;化学气相沉积制备过程中,当微波功率500W,氢气和甲烷流量比100:6,气压4.0kPa,沉积时间5min时,复合纤维管外壁和端口内壁均匀沉积长径比较大且直径均匀分布的碳纳米纤维,碳纤维直径约50nm;复合纤维成分为碳纳米纤维、镍和三镍化磷合金相,其中碳纳米纤维表现为石墨相.表面覆盖有碳纳米纤维的镍管复合材料,增加了材料自身的吸附存储和导电性能,可应用于多相催化、电容存储和电极材料等领域. 相似文献
17.
The dispersion behavior of micro-diamond particles ranging from 0 to 0.5 micron was compared between in DI water and in electroless nickel solution. The effects of the concentration of electroless solution, temperature, ultrasonic treatment, stirring speed, and baffles on the size distribution of micro diamond particles in electroless nickel solution were studied. Results show that the dispersion of micro diamond particles in DI water is obviously superior to that in electroless nickel solution. Micro diamond particles agglomerate evidently when the concentration of electroless solution Velect:VDI in dispersion media exceeds 5‰. Diamond particles agglomerate more and more seriously with the increase of the ion concentration. Applying ultrasonic, increasing stirring speed and adding baffles are helpful to improving the dispersion of diamond particles in the electroless nickel solution and its uniform distribution in the Ni-P coating. 相似文献
18.
Removal of nickel from spent electroless nickel-plating bath with nickel foam cathode 总被引:1,自引:0,他引:1
0 INTRODUCTIONElectrolessnickel platingtechnologywasamethodofdepositingnickelionsonthesurfaceofmetalmaterialswithdifferentshapes .Thisprocesshadspecialadvantages ,andwasthereforewidelyap pliedinaerospace ,electronics ,petrochemistry ,foodindustriesandsoon[1]… 相似文献
19.
硫脲对Ni-P镀层腐蚀行为的影响 总被引:2,自引:0,他引:2
在镀液中添加硫脲,分析了硫脲对Ni-P镀层沉积速度、表面形貌、孔隙率等的影响,并通过极化曲线和交流阻抗测试了硫脲对Ni-P镀层腐蚀性的影响。结果表明,当镀液中添加1 mg/L硫脲时,镀层的沉积速率加快,腐蚀速率增大。这主要是因为镀液添加硫脲后,镀层的孔隙率加大,促进了腐蚀介质渗入到基体表面,增加了腐蚀微电池的数量,形成了大阴极(镀层)-小阳极(基体)腐蚀微电池,使自腐蚀电流密度增大,电荷转移电阻减小。当镀液中添加硫脲质量浓度大于3 mg/L时,镀液被毒化,无法施镀。 相似文献
20.
稀土对化学镀镍的影响初探 总被引:1,自引:0,他引:1
研究了3种稀土元素对化学镀镍溶液稳定性和沉积速度的影响。结果表明,3种稀土对溶液均有影响,其中Y的影响较为显著,La的影响程度最小。适量的稀土可以提高镀液的稳定性和沉积速度,添加0.02g/L的Y可以提高镀液的稳定性,并且,在稀土镀液中所沉积的镀层比在基础镀液所获镀层具有更好的耐磨性能,并初步探讨了稀土在镀液中的作用机理。 相似文献