正交试验优化电镀Zn-Ni-P合金工艺

选取影响电镀Zn-Ni-P合金的6个工艺参数，设计了125(56)正交试验方案，探讨了镀液组成和电镀制度对Zn-Ni—P合金镀层性能的影响，用极差法分析了各工艺参数对镀层性能影响的显著性并确定了最佳工艺条件。优化验证实验结果表明：该工艺稳定，得到光亮、致密、外观平整的Zn-Ni—P合金镀层，得到的锌镍磷合金镀层的耐蚀性优于锌镍合金，且其耐蚀性随镀层中磷含量的增大而提高。     

高稳定性化学镀镍磷合金工艺研究

采用正交试验法研究了络合剂,促进剂,稳定剂以及温度对镀层和溶液性能的影响,从而得到了一种高稳定性的化学镀镍磷合金工艺。该工艺所得镀层磷含量较高,沉积速度快,镀液使用寿命长,并已在工业生产中加以应用。     

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。     

镁合金化学镀光亮镍磷合金

研制了一种能在镁基上直接进行化学镀镍磷合金的新工艺,镀层呈银白色,表面平整光亮.镀液为碱性介质,基础配方为:硫酸镍、复合络合剂、导电盐和其它添加剂.通过X射线衍射仪(XRD)和扫描电镜(SEM)等方法研究了电流密度、温度、pH值等参数对镀层磷含量、镀层显微硬度等性能的影响.结果表明,该工艺具有高效稳定、易于控制、操作简便等特点,适宜于产业化应用.     

镍磷合金镀层表面强化性能的获得

镍磷合金化学镀是一项很有应用前途的表面强化技术,其镀层具有良好的性能。本文研究了镍磷合金镀层的显微硬度和耐磨性能,结果表明,镀层的性能和磷含量有关,还受到热处理的影响,且硬度和耐磨性变化并不一致,实际应用需选择恰当的工艺参数,以获得最佳的表面强化性能。     

化学镀镍磷合金工艺研究及其在钕铁硼永磁体抗蚀上的应用

采用正交试验法筛选络合剂,确定了以柠檬酸、琥珀酸和苹果酸复配作为络合剂的化学镀非晶态镍磷合金工艺,具有高稳定性、高装载量等优点.把该工艺应用于烧结Nd-Fe-B永磁体的抗蚀上,达到预期耐腐蚀的要求.     

化学镀镍磷合金镀层耐蚀性的研究

研究了化学镀镍磷合金镀层的耐蚀性与络合剂、磷含量、热处理温度的关系,并在烟道中进行了挂片实验。     

磷含量在化学镀层中对其性能的影响

采用酸性化学镀镍－磷合金电解液，通过改变不原剂浓度，制备了一系列不同磷含量的镍－磷合金镀层，以研究其中磷含量对镀层性能的影响。实验结果表明，镀层耐蚀性，硬度等性能与磷含量有直接关系，文他这种关系。     

pH值对中温化学镀镍-磷的影响

化学镀镍-磷技术作为表面强化的一种途径,已经得到越来越广泛的应用和不断的发展.为了研究pH值对镀层性能的影响,采用中温化学镀镍工艺,以醋酸钠为缓冲剂,以乳酸为络合剂,在酸性体系中化学沉积镍-磷合金.研究了溶液的pH值对化学镀镍-磷合金的沉积速度、镀层性能的影响.结果表明:pH值对镀速的影响较大,随着pH值的升高,镀速逐渐增加,镀层磷含量逐渐降低;在一定范围内硬度和腐蚀速度随pH值的升高而增加,在pH值为5.1时,镀层的综合性能达到最好.     

光亮剂对化学镀镍磷工艺及其镀层性能的影响

研制开发了一种新型的化学镀镍光亮剂。试验结果表明，光亮剂在化学镀镍过程中没有参与反应，却对磷的沉积起到了积极的催化作用，显著地提高了镀层中的磷含量；当光亮剂的加入量达到5～6mL/L时，镀层中的磷含量可提高到35.63%～39.03%，同时可得到全光亮的镍-磷合金镀层，有效地改善了镀层的表面质量，且出光速度快，镀液稳定可靠。通过扫描电镜和X射线衍射对高磷镍-磷合金镀层的分析表明，镀层为非晶态结构。显微硬度，磨损率以及耐蚀性测试结果表明，镀态下镍-磷合金镀层的硬度，耐磨性和在10%盐酸中的耐蚀性随着光亮剂的增加而降低。     

Preparation of amorphous-nanocrystalline composite structured Ni-P electrodeposits

Amorphous-nanocrystalline composite structured Ni-P deposits (with phosphorus content of 5-9 wt.%) show better corrosion resistance than that of microcrystalline structured Ni-P deposits, and better abrasion resistance than that of amorphous Ni-P deposits. In order to get amorphous-nanocrystalline composite structured Ni-P deposits on AISI 431 stainless steel, electroplating parameters that affect phosphorus content in Ni-P deposits (temperature, current density, pH, H₃PO₃ concentration and agitation rate) are analysed by orthogonal experimental design (OED) in this paper. The analysis indicates that pH value and phosphorous acid concentration are key variables, their interactive effect on Ni-P composition should be taken into account. The effects of pH and H₃PO₃ concentration of the electroplating bath on phosphorus content in Ni-P deposits are further examined by the method of steepest ascent and central composition design (CCD). On the basis of results and discussion in experimental design sections, various Ni-P deposits with approx. 5-9 wt.% phosphorus can be galvanostatically electroplated by controlling the key variables and these deposits are confirmed to be amorphous-nanocrystalline composite structure in XRD, TEM tests.     

AZ91D镁合金的化学镀镍

使用硫酸镍作为化学镀镍磷镀液的主盐,直接在AZ91D镁合金基体上化学镀镍.使用扫描电镜和X射线衍射技术分析镀层的表面形貌和组织.化学镀镍磷镀层是致密的,无明显缺陷,其磷含量约为372 mass%.化学镀镍磷镀层的显微硬度值约为660 VHN,化学镀镍的沉积速度为23 μm/h.前处理过程中的酸洗步骤使镁合金基体产生粗糙的表面,从而使镀层和基体之间起到了互锁的作用,增加了镀层的结合力.     

化学镀Ni-P合金镀层在海水中的耐蚀性

在Cu-Ni合金表面化学镀Ni-P合金,研究了镀层在3.5%NaCl溶液中的电化学性能,通过失重法测试了Ni-P合金镀层、Cu-Ni合金在静态和动态海水中的腐蚀速率,利用表面分析技术研究了Ni-P合金镀层的组织结构与成份XRD分析结果表明Ni-P镀层是典型的非晶态合金,随着镀层P含量的增加,衍射峰越来越宽化,其非晶化的程度增高.动电位极化试验表明Ni-P镀层的耐蚀性主要受镀层中的P含量的影响,随P含量的增加,镀层的自腐蚀电位正移,腐蚀电流减小;失重试验表明Ni-P合金镀层在静态海水和流动海水中的腐蚀速率大大低于Cu-N合金     

Characterization of Electroless Ni-P Deposits on Surface of AZ91D Magnesium Alloy

Characterization of electroless nickel deposits on magnesium alloys was investigated by X-ray diffraction(XRD),scanning electron microscope(SEM),energy dispersive spectrometer(EDS)and electrochemical potentiodynamic polarization analysis.The result of XRD showed that the electroless nickel deposits on magnesium alloys were composed mostly of amorphous Ni-P and partially of microcrystalline nickel.The phosphorus content in the Ni-P deposits was 10.8%by the calculation of EDS.SEM micrographs showed that morphology of electroless nickel deposits on magnesium alloys was a typical cellular structure,and the growth of cellular structure was influenced by surface condition of substrate.Zinc layer between substrate and electroless nickel deposits was not found by the results of SEM and EDS,which indicated that the zinc layer on the surface of magnesium alloy was very thin,and the zinc would dissolved while being immersed in electroless nickel plating solution.The thin zinc layer was almost dissolved completely before Ni-P plating.The result of electrochemical potentiodynamic polarization analysis showed that the corrosion potential Ecorr of electroless nickel deposits in 3.5%NaCl solution was about-0.53 V,which was 1 V higher than that of magnesium alloys substrate.And corrosion current density of Ni-P deposits in 3.5%NaCl solution was much smaller than that of magnesium alloys substrate at the same potential value,which indicated that corrosion resistance of electroless Ni-P deposits was excellent.Discoloration time of concentrated nitric acid test for electroless nickel deposits on magnesium alloys was 445 s,which also indicated excellent corrosion resistance.     

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.     

钨铜合金表面化学镀Ni-P镀层性能研究

从钨铜合金表面化学镀Ni-P镀层的表面形貌及成分,镀层结构,外观,结合力.硬度,耐磨性,孔隙率,纤焊性等方面进行了检测和表征.结果表明,化学镀Ni-P合金层磷含量为11.37%,属于高磷镀层,主要为非晶型结构,在钨铜合金表面化学镀Ni-P合金可以大大提高钨铜合金的硬度和耐磨性,且Ni-P合金镀层与钨铜合金基体结合强度好,孔隙率低,纤焊性好.     

黄铜化学镀镍磷合金的工艺与性能

研究了黄铜化学镀镍磷合金的工艺。对镀层的成分、结构、结合力和耐腐蚀性进行了分析研究。实验表明:采用酸性镀液施镀,可得到结合力强,磷含量大于12％,非晶态结构的Ni-P合金镀层;并具有优异的耐蚀性。     

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...     

Ni-P化学镀层的塑脆性能研究

利用单摆划痕法的动态加载特性，研究了Ni-P化学镀层本身的塑脆性能。分析讨论了磷含量和热处理温度对镀层的塑脆性能影响。临界划痕深度D‘、临界法向力Fnc和划痕断裂韧性Kc‘在衡量镀层塑脆程度方面是一致的，其中，D‘和Fnc可作为塑脆转变判据。