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通过大量试验,研制成功一种新型的镀镍溶液。结果表明,这种新型的镀镍溶液具有优良的电化学性能,极低的镀层内应力,采用这种工艺在不锈钢(1Crl8Ni9Ti)上镀镍可有效地防止其在高温(900℃)氢气气氛下变黑和镀层起泡。实验中比较了两种不同添加剂镀液的电化学性能,包括均镀能力、深镀能力和阴极电流效率等,并测定了镀层的内应力,分析其原因与影响。 相似文献
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介绍了叠层片式电感三层端头电极即银基底电极、镍层、锡-铅合金镀层的性能及制备工艺。提出三层端头电极的质量控制,并分析了常见的质量问题。银端头的质量取决于合适的银端`浆烧成曲线和烧结气氛;镀镍层应有较低的内应力,镀镍层内应力受镀镍液各成分浓度、无机杂质、有机杂质和pH值的影响;MLCI端头电极锡-铅合金电镀工艺及维护,镀后的清洗、MLCI的储存影响镀层的耐焊性和可焊性,对锡-铅合金镀层的耐焊性和可焊性进行了检验以获得合格的MLCI产品。 相似文献
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化学镀Ni-P合金镀层内应力的研究 总被引:4,自引:0,他引:4
采用薄片弯曲法测量不同pH值和不同热处理对化学镀镍层内应力的影响,分析了产生变化的原因.结果表明,当镀液pH值为3.8~4.1和4.4~4.6时,镀层受到的内应力为压应力,而当镀液pH值为4.8~5.1时,镀层受到的内应力为拉应力.镀液pH值越高,镀层中磷含量越低,其内应力越高.经过200℃×1 h热处理,镀层的内应力减小;经过400℃×1 h或600℃×1 h热处理,镀层的内应力增大. 相似文献
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一、概述镍镀层具有悠久的应用历史,人们对镍镀层认识从感性到理性也就越来越深入,越来越丰富,在国外对镀镍溶液成份研究表明,溶液中钠离子对镀镍层结构有较大的影响。早在本世纪七十年,在英、美,有关文献中已明确指出,镀液中的钠离子会使镍镀层产生呈层状纤维结构,因而镀层内应力高、结合力差、脆性大。为避免钠离子对镍镀层结构的影响,国外一般都已采用不含钠离子的镀镍工艺。但在我国却仍有相当多的镀镍溶液采用含钠离子的工 相似文献
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化学镀镍-铜-磷三元合金工艺的研究 总被引:1,自引:2,他引:1
为提高化学镀镍-磷合金镀层的性能及获得多种性能的合金镀层以拓宽其应用范围。在化学镀镍-磷合金液中加入硫酸铜制得镍-铜-磷三元合金。研究了镀液中硫酸镍、次磷酸钠、柠檬酸钠、硫酸铜、稳定剂、光亮剂的含量以及pH值和温度等因素对合金镀层的外观、沉积速度及铜含量的影响。通过5%氯化钠溶液和10%硫酸溶液浸泡试验比较了所得镍-铜-磷合金镀层与镍-磷合金镀层以及前人制得的镍-磷合金镀层的耐蚀性,同时比较了上述镀层的其它性能。结果表明,所得镍-铜-磷合金镀层的耐蚀性、外观、结合力、孔隙率、沉积速度、硬度和耐磨性等性能优于镍-磷合金及前人制得的镍-铜-磷合金镀层。 相似文献
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A standard Ni-Mo/-Al2O3 catalyst containing 4 wt% Ni was modified by addition of nickel (2 wt%) and, alternatively, of vanadium (4 wt%) by contacting with a solution of the respective metal naphthenate. The catalysts were sulfided and tested in a batch reactor at 350°C and 165 bar for hydrogenation of naphthalene and for hydroprocessing of dibenzothiophene. Reaction networks were determined for each reactant, and the dependence of the pseudo firs-torder rate constants on the amount of nickel and of vanadium in the catalyst was used to determine the effects of nickel sulfide and of vanadium sulfide deposits on catalyst performance. For example, the nickel sulfide deposits only slightly affected the rate constants for hydrogenation in either network, but the vanadium sulfide deposits led to a decrease of at most 50% in the rate constants for hydrogenation reactions in the naphthalene network and to a doubling of the rate constants for hydrogenation reactions in the dibenzothiophene network. The nickel sulfide deposits led to almost no change in the rate constant for hydrogenolysis of dibenzothiophene (to give biphenyl), but the vanadium sulfide deposits led to a threefold decrease in the rate constant for this reaction. The nickel sulfide deposits have little activity for reactions giving lower-molecular-weight (cracking) products, but the vanadium sulfide deposits have a relatively high activity for cracking, which suggests that they are acidic. The effects of the deposits are complex, as they both block catalytic sites and form new ones. The results indicate a need for representing the nickel and sulfide deposits separately in process models for heavy oil hydroprocessing. 相似文献
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镁合金化学镀镍工艺的研究 总被引:3,自引:0,他引:3
采用硫酸镍为主盐、次磷酸钠为还原剂,并在镀液中加入氟化物和稳定剂,研究了镁合金的化学镀镍工艺.运用正交试验分析了镀液中各主要组分对镀速及耐蚀性等影响,优选化学镀最佳工艺.该工艺沉积速率快,镀层耐蚀性优异.运用X-射线衍射方法对镀层的组织结构进行了分析,结果表明,镁合金化学镀镍层由非晶态的镍及部分微晶的镍组成. 相似文献
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The electrodeposition behavior of nickel was investigated at glassy carbon and polycrystalline copper electrodes in the 1-ethyl-3-methylimidazolium dicyanamide (EMI-DCA) room-temperature ionic liquid. Amperometric titration experiments suggest that Ni(II) reacted with DCA− anions forming [Ni(DCA)4]2− complex anion, which could be reduced to nickel metal via a single-step electron transfer process. However, the anodic dissolution of the nickel deposits was sluggish. The electrodeposition of nickel proceeds via three-dimensional progressive nucleation with diffusion-controlled growth on both glassy and copper substrates. Scanning electron microscopy images of the nickel deposits indicated that the morphology of the nickel electrodeposits is dependent on the deposition potential. Atomic force microscopy topography illustrated that the roughness of the nickel-deposited surface increased with decreasing deposition potential. The crystalline nature of the nickel deposits was revealed by powder X-ray diffraction spectroscopy results which indicated that the grains size of the nickel deposits decreased with decreasing deposition potential. 相似文献
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铝合金化学镀Ni-P-B的研究 总被引:3,自引:1,他引:3
以二甲基胺硼烷(DMAB)为还原剂,在铝合金上获得了化学镀镍低磷低硼镀层,研究了硫酸镍、次磷酸钠、DMAB、络合剂、pH值和稳定剂对镀层的沉积速度、显微硬度和微观形貌的影响。通过正交实验和单因素实验,确定了最佳工艺配方为:24g/L硫酸镍,适量DMAB,12g/L次磷酸钠,3mg/L硫脲,30mL/L络合剂。所获得的化学镀镍镀层中P、B、Ni的质量分数分别为:1.8l%、0.26%和97.93%。该镀层与基体的结合力良好,硬度在550~710Hp。范围内,在铝质活塞上应用获得了满意的效果。 相似文献