共查询到20条相似文献,搜索用时 109 毫秒
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锌-镍/纳米氧化铝复合电沉积及镀层结构性能研究 总被引:3,自引:0,他引:3
以冷轧钢板为基材,研究了Zn-Ni/纳米Al2O3复合镀层的电沉积工艺,分析了复合镀层的成分和晶体结构.通过中性盐雾试验,考察了复合镀层的耐蚀性.采用X射线衍射和扫描电镜,分别表征了复合镀层腐蚀产物的微观结构以及镀层的表面形貌.结果表明:Zn-Ni/纳米Al2O3复合镀层的结晶比Zn镀层及Zn-Ni合金镀层更细致,晶粒排布更均匀、整齐.当Zn-Ni/纳米Al2O3复合镀层中Ni和Al2O3的质量分数分别为13%左右和0.40%~0.60%时,其耐蚀性最好.Al2O3颗粒的掺入可降低镀层的孔隙率,使镀层平整、致密,从而提高了镀层的耐蚀性. 相似文献
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本文研究光亮锌铁合金镀层的电镀工艺.讨论了评价合金电镀液均镀能力的合理方法.并用扫描电子显微镜和X射线衍射仪分析了镀层的结构和相组成.用电化学方法研究了沉积机理,提出了添加剂的吸附模型.按本工艺可镀取含Fe5%左右的光亮锌铁镀层.银白光亮镀层钝化后具有美丽的天蓝色或金黄色外观,耐蚀性更佳,在某些场合可望作为防护装饰镀层. 相似文献
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酸性化学镀Ni-Zn-P工艺的研究 总被引:2,自引:0,他引:2
研究了硫酸锌、添加剂和pH值对镀层沉积速率及镀层腐蚀电位的影响.测试了镀层在质量分数为3.5%的NaCl溶液中的Tafel曲线;用电化学阻抗实验对镀层的耐蚀性进行了测试.研究结果表明:镀层在质量分数为3.5%的NaCl溶液中,相对甘汞电极的腐蚀电势为-0.600 9 V,比化学镀Ni-P合金镀层的腐蚀电势-0.343 V低258 mV. 相似文献
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钨对化学镀Ni-W-P合金镀层结构及性能的影响 总被引:4,自引:0,他引:4
通过不同的化学镀工艺配方,获得了4种不同钨含量的化学镀Ni-W-P三元合金镀层.研究了钨含量对镀层结构、硬度及在5%H2SO4溶液中耐蚀性的影响规律.研究发现,化学镀Ni-W-P三元合金镀层的结构受镀层中钨含量的影响较大,非晶态Ni-W-P三元合金镀层所需磷含量较非晶态Ni-P二元镀层所需磷含量要低,并且钨含量越高,所需磷含量越少;镀层硬度随镀层结构从非晶态→混晶态→纳米晶态转变而增加;镀层的耐蚀性随镀层中钨含量增加而变好,且非晶态镀层较混晶态和纳米晶态镀层更易形成钝化区. 相似文献
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通过称量法测试了镀铬层在不同温度、不同质量分数Na2S溶液中的腐蚀速率,并采用恒电位极化法研究了镀铬层在Na2S溶液中的电化学行为,分析了各因素对镀铬层腐蚀行为的影响。研究结果表明:镀铬层在Na2S溶液中的腐蚀过程有钝化产生;同一温度条件下,提高浓度可加速镀铬层的钝化。 相似文献
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The electrochemical corrosion behavior of sealed Ni–TiO2 composite coating for sintered NdFeB magnet
Xiao-kui Yang Qing Li Jun-ying Hu Xian-kang Zhong Shi-yan Zhang 《Journal of Applied Electrochemistry》2010,40(1):39-47
In this article, a protective sealed Ni–TiO2 composite coating (SCC) was prepared on sintered NdFeB magnet by pulse current electrodeposition and sol–gel combined technique. For a comparison, unsealed Ni–TiO2 composite coating (UCC) was also studied. The surface morphologies of composite coating were studied using scanning electron microscope (SEM). The structure of sealing layer was studied by Fourier transform infrared (FT-IR) spectrum. The anticorrosive properties of composite coating in neutral 3.5 wt% NaCl solution were evaluated by potentiodynamic polarization measurements and electrochemical impedance spectroscopy (EIS). In order to further investigate the anticorrosive properties of SCC, a long-term immersion test was carried out in neutral 3.5 wt% NaCl solution. The results of corrosion tests showed that due to the blocking effect of sealing layer, SCC can suppress the corrosion process by holding back the transfer or diffusion of corrosive medium, and therefore showed the excellent anticorrosive properties for sintered NdFeB magnet. 相似文献
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Majid Yousefi Mojtaba Ghatee Mashallah Rezakazemi Seyed Hadi Ghaderi 《International Journal of Applied Ceramic Technology》2021,18(6):2197-2206
In this paper, SiC coating was prepared using the polymer-derived ceramic method; then the effect of nano-alumina as a filler material was studied. First of all, polycarbosilane(PCS) was dissolved in xylene; after that, different amounts of nano-alumina particles were added to the solution. The coating was deposited on the alumina substrate using the dip-coating method; this was followed by sintering at 1200℃. The phase content and microstructure of the samples were studied by X-ray diffraction and scanning electron microscope methods, respectively. Nanohardness, Young's modulus, and coating adhesion were investigated by a nanoindentation method. The sheet resistance was evaluated using the four-point probe technique; also, the wear resistance of the coating was studied by applying the pin-on-disk method. It was found that the addition of the nano-alumina filler up to 20 wt% drastically improved the adhesion and wear resistance of the SiC coating. 相似文献
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本文对AZ31镁合金表面稀土转化成膜工艺进行了研究。分析了不同的成膜工艺参数丽土盐溶液组成、转化成膜时间)对稀土转化膜的形貌及耐蚀性能的影响。扫描电镜分析了不同成膜工艺形成的稀土转化膜的表面形貌;极化曲线研究了转化膜的电化学腐蚀行为。结果表明:当转化液中硝酸铈浓度为4.3423g·L^-1和硝酸镧浓度为4.3302g·L^-1时,转化膜的耐蚀性能最好;成膜时间对膜的耐蚀性也有不同程度的影响。 相似文献
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Mahdi Elyasi Kojabad Masumeh Momeni Ali Akbar Babaluo Mohammad Javad Vaezi 《化学工程与技术》2020,43(7):1451-1460
Polyether block amide (PEBA) polymeric layers were prepared on polysulfone (PSf) supports via dip coating. The effects of the coating speed and the solution concentration on the membrane performance were studied. The membranes were characterized by scanning electron microscopy, Fourier transform infrared spectra, and gas permeation. The coating speed was adjusted in the range of 0.32–0.48 cm s−1 at a solution concentration of 3 wt % to obtain suitable membranes so that the CO2 permeance and the CO2/N2 selectivity increased by more than three and ten times, respectively, compared to other speed ranges. Statistical analysis also showed that the effect of the interaction between solution concentration and coating speed is more considerable than the separate effects of both factors. 相似文献
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铝及其合金电镀光亮锡-铅合金工艺研究 总被引:1,自引:0,他引:1
研究了采用浸锌-锡合金与预镀镍相结合的方法,在铝及其合金表面形成一层中间层再电镀光亮锡-铅合金工艺。介绍了铝及其合金制件的脱脂、碱蚀、出光及预镀等预处理工艺和配方,探讨了浸锌-镍合金溶液的配制、温度及时间对镀层性能的影响。结果表明,该工艺所获得的镀层结晶细致、光亮、焊接性能高、结合力强。 相似文献