Ni-Al2O3复合镀层的腐蚀摩擦学性能研究

用电镀方法制得Ni-Al2O3复合镀层,研究电镀Ni-Al2O3复合镀层的结构以及其硬度、耐磨性、抗腐蚀性与电镀电流密度的关系。结果表明:复合镀层的显微硬度比纯镍镀层硬度成倍提高,复合镀层耐磨性比镍镀层提高20%以上;抗腐蚀性提高70%以上。X射线衍射结果显示,复合镀层由Ni及非晶Al2O3组成,Ni相为面心立方晶体结构,晶格常数为0.353nm,小于纯镍镀层,晶粒尺寸为23.8nm,大于纯镍镀层。     

微纳米材料对镀层硬度耐磨性的影响

通过制备Ni,Ni-SiC(微米)复合电镀,Ni-SiC(纳米)复合电镀,Ni-CNTs复合电镀,Ni-CNTs-SiC(微米)复合电镀,Ni-CNTs-SiC(纳米)复合电镀六种镀层,研究这六种镀层的显微硬度、耐磨性,并进行对比。分析了碳纳米管、碳化硅颗粒的加入对镀层的显微硬度和耐磨性的影响。试验结果表明,纳米复合电镀层表面平整光滑,其显微硬度、耐磨性也较纯镀镍镀层有显著的提高。     

镍-钨-碳化硅非晶复合刷镀工艺的研究

为进一步提高非晶态镍－钨合金镀层的硬度,耐磨和耐蚀性能,在镍－钨刷镀液中加入适量碳化硅微粒,共沉积制得含碳化硅26．0－21．3％（质量分数）的非晶态镍－钨－碳化硅复合镀层。利用X射线衍射技术分析了所得镍－钨－碳化硅镀层的结构,研究了镀层中碳化硅含量,热处理温度复合镀层硬度,耐磨性和抗高温氧化性的影响。结果表明：碳化硅的弥散强化作用和热处理能显著提高复合镀层的硬度,耐磨性和抗高温氧化性。     

Ni-ZrO2纳米微粒复合镀层性能研究

采用正交试验对Ni-ZrO2纳米微粒复合电镀中影响镀层硬度和耐蚀性等性能的电流密度、镀液温度、极间距、ZrO2纳米微粒质量浓度等因素进行了实验研究,并测定了镀层的形貌、结构、硬度、耐蚀性和结合强度.结果表明Ni基纳米微粒ZrO2复合电镀可以改变镀层的硬度及耐蚀性,且有较好的结合强度.实验研究条件下最优工艺条件为:θ为4...     

电沉积Ni-TiB2复合镀层性能的研究

用复合电沉积方法制备Ni-TiB2复合镀层.与纯Ni镀层对比,考察了TiB2对复合镀层显微硬度、摩擦磨损性和耐蚀性的影响.结果表明:当镀液中TiB2的质量浓度为25 g/L时,复合镀层维氏硬度达到6 400 MPa,较纯Ni镀层5200 MPa增加了23%左右;当镀液中TiB2的质量浓度为15 g/L时,测试条件下复合镀层磨损质量为0.11 mg,耐磨性比纯Ni镀层提高了约5倍;当镀液中TiB2:的质量浓度为15 g/L时,在3.5%的NaCI溶液中测得复合镀层Jcorr为1.123μA/cm2,为纯Ni镀层的25%左右,其耐蚀性也得到了提高.     

烧结钕铁硼永磁体复合电镀镍–氧化铈工艺和镀层性能

以烧结NdFeB永磁体为基体,采用复合电沉积法制备了Ni–CeO2复合镀层。镀液组成与工艺条件为:NiSO4250 g/L,NiCl240 g/L,H3BO335 g/L,纳米CeO210 g/L,十二烷基硫酸钠0.05 g/L,温度45°C,电流密度3 A/dm2,时间30 min。对比研究了纯镍镀层和Ni–CeO2复合镀层的表面形貌、结构组成、耐蚀性、结合力、显微硬度等性能。结果表明,与纯镍镀层相比,Ni–CeO2复合镀层结晶更为细致,在3.5%NaCl溶液中的耐蚀性提高,显微硬度由纯镍镀层的358.7 HV提高至428.3 HV,结合力明显增强。     

工艺参数对Ni-SiC纳米复合镀层硬度的影响

为了提高结晶器铜板的使用寿命,采用电沉积的方法得到了Ni-SiC纳米复合镀层。采用单因素实验法对影响电镀层硬度的阴极电流密度、SiC纳米微粒添加量、pH及温度等进行了研究。结果表明,Ni基SiC纳米复合电镀工艺参数均对复合镀层的硬度有影响。对Ni-SiC纳米复合镀层的表面形貌进行了测试,确定最优工艺条件为8g/L SiC纳米微粒,Jκ为3A/dm2,pH为4.0,θ为30℃。纳米复合镀层的硬度与纯镍镀层相比有明显提高。     

磁场辅助电沉积镍-纳米碳化硅复合镀层及其性能

采用磁场辅助电沉积法在低碳钢表面上制备了纯Ni镀层和Ni–纳米SiC复合镀层。镀液组成和工艺条件为：NiSO₄·6H₂O285 g/L,NiCl₂·6H₂O28 g/L,H₃BO₃ 25 g/L,十六烷基三甲基溴化铵80 mg/L,纳米SiC(平均粒径35 nm) 0 g/L或7 g/L,pH 4.8,温度46℃,电流密度5.5 A/dm²,占空比30%,磁场强度0.2 A/m或0.4 A/m,时间30 min。对比了纯Ni镀层和Ni–纳米Si C复合镀层的组织结构、显微硬度和耐磨性,分析了磁场强度对镀层性能的影响。结果表明,在0.2 A/m磁场强度下所得Ni–纳米SiC复合镀层比相同磁场强度下制备的纯Ni镀层更均匀细致,显微硬度更高,耐磨性更强。增大磁场强度至0.4A/m时,Ni–纳米SiC复合镀层的性能进一步提升。     

SiC强化镍基纳米复合电刷镀层的干摩擦磨损特性

采用电刷镀技术制备了快速镍和,n-SiC/Ni、n-SiC/Ni-W复合镀层,研究了镀层的干摩擦磨损特性,测定了镀层的显微硬度,采用扫描电子显微镜(SEM)观察分析了镀层磨痕形貌.结果表明:纳米粒子的加入可以显著地提高镀层的耐磨性.纳米复合镀层的磨损机制以磨粒磨损为主,而纯镍镀层以粘着磨损和磨粒磨损为主.     

Ni-ZrO2复合镀层的结构表征

采用复合电沉积制备Ni-ZrO2复合层。采用X-射线衍射检测ZrO2的加入对镍镀层结构的影响,如衍射峰的强度、金属电沉积时晶粒的择优取向。测试表明,Ni和ZrO2各自在特定的角度分别出现其独特的衍射特征峰,互不干扰,镀层中ZrO2含量增高,衍射强度变强。ZrO2在镀层的掺杂,镀层的晶粒尺寸由29.29 nm降至21.78 nm,镀层晶粒细化。     

Effect of Annealing Temperature and Alumina Particles on Mechanical and Tribological Properties of Ni-P-Al<Subscript>2</Subscript>O<Subscript>3</Subscript> Composite Coatings

In this study, the effect of annealing temperature and alumina particles on micro-hardness, corrosion, wear, and friction of Ni-P-Al₂O₃ composites coating is studied. The electroless nickel composite coating with various alumina particle content is deposited on a mild steel substrate. The corrosion behaviour and tribological behaviour (wear and friction) of the composite coated samples are investigated and compared with Ni-P coated samples. The micro-hardness, wear resistance, and corrosion resistance of the composite coating improved significantly after heat treatment (400 °C) and in the presence of alumina particles. The composite coating deposited with alumina particle concentration of 10 g/L in an electroless bath and heat treated at 400 °C shows excellent results compared to Ni-P, as-deposited Ni-P-Al₂O₃ coating and coatings heat treated at different annealing temperature (200 °C, 300 °C, and 500 °C). Microstructure changes and composition of the composite coatings due to incorporation of alumina particles and heat treatment are studied with the help of SEM (scanning electron microscopy), EDX (energy dispersive X-ray analysis and XRD (X-ray diffraction analysis).     

Effect of particle size on the co-deposition of diamond with nickel in presence of a redox-active surfactant and mechanical property of the coatings

Particle reinforced Ni/diamond composite coatings containing various amount of the reinforcement (up to 57.6 vol.%) were prepared by the electroplating technique using a Watt's nickel bath in which the diamond particles were dispersed with the aid of a redox-active surfactant containing an azobenzene moiety. Five different sizes of diamond particles with the mean diameter ranging from 0.21 to 2.91 μm were used to investigate the effect of the particle size in their co-deposition with nickel under the influence of the above redox-active surfactant and the mechanical property especially the micro-hardness and the abrasion wear of the composite coatings reinforced with various amount of the diamond particles was studied. Among all, the smallest diamond particles exhibited the highest particle co-deposition of 57.6 vol.%. The micro-hardness and the wear resistance of this composite with the 57.6 vol.% diamond were about 4.5 and 14 times, respectively, than that of a nickel coating without any reinforcement.     

Ni-ZrO2纳米复合电铸层耐蚀性的研究

用静态浸泡实验法研究了镍镀层和Ni-ZrO2纳米复合电铸层在质量分数分别为10% HCl溶液和10% H2SO4溶液中的耐蚀性.用SEM观察了各种样品腐蚀后的表面形貌,分析了纳米ZrO2微粒复合量对复合电铸层耐蚀性的影响,同时对纳米复合电铸层的腐蚀机理进行了初步探讨.结果表明,脉冲纳米复合电铸层的耐蚀性明显优于相同条件下制备的镍镀层,镀液中纳米ZrO2悬浮量对提高纳米复合电铸层耐蚀性有一定程度的影响.     

脉冲电沉积纳米镍-碳化硅复合镀层的性能

分别采用直流(DC)和换向脉冲电流(PRC)电沉积法制得纳米Ni-SiC复合镀层。采用X射线衍射仪、扫描电镜、能谱仪对比研究了纯Ni镀层和Ni-SiC复合镀层的微观结构、宏观残余应力、表面形貌及成分。用浸泡法研究了不同镀层在3.5%(质量分数)NaCl和10%(体积分数)H2SO4溶液中的腐蚀行为。结果表明,脉冲电沉积能改变镀层的微观结构,有效提高镀层硬度,降低宏观残余应力。脉冲电沉积所得到的纯Ni镀层和纳米Ni-SiC复合镀层在3.5%NaCl及10%H2SO4溶液中的耐蚀性均优于直流镀层。脉冲镀层在3.5%NaCl溶液中受腐蚀很轻,主要腐蚀形态为点蚀,而在10%H2SO4溶液中,SiC粒子作为增强相使镀层的耐腐蚀性进一步提高。     

镍-碳化钨纳米复合镀层的制备与性能

采用电镀的方法制备出Ni-WC纳米复合镀层,镀液组成为:NiSO4·7H2O 250 g/L,NiCl2·6H2O 30 g/L,H3BO3 30 g/L,光亮剂0.1 g/L,纳米WC颗粒5～ 30 g/L,表面活性剂及分散剂适量.研究了温度、电流密度及pH对复合镀层外观的影响,得到最佳电镀工艺条件为:温度50～55...     

Effect of titania particles preparation on the properties of Ni–TiO2 electrodeposited composite coatings

In this paper, the effect of titania particles preparation on the properties of Ni–TiO₂ electrocomposite coatings has been addressed. Titania particles were prepared by precipitation method using titanium tetrachloride as the precursor. The titanyl hydroxide precipitate was subjected to two different calcinations temperatures (400 and 900 °C) to obtain anatase and rutile titania particles. These particles along with commercial anatase titania particles were separately dispersed in nickel sulfamate bath and electrodeposited under identical electroplating conditions to obtain composite coatings. The electrodeposited coatings were evaluated for their microhardness, wettability, corrosion resistance, and tribological behavior. The variation of microhardness with current density exhibited a similar trend for all the three composite coatings. The composite coating containing anatase titania particles exhibited higher microhardness and improved wear resistance. However, the corrosion resistance of the composite coating containing commercial titania powder was superior to that of plain nickel, Ni–TiO₂ composite coatings containing anatase and rutile titania particles. The poor corrosion resistance of these composite coatings was attributed to the higher surface roughness of the coatings. This problem was alleviated by incorporating ball-milled titania powders. The composite coatings with higher surface roughness were modified with a low surface energy material like fluoroalkyl silane to impart hydrophobic and superhydrophobic properties to the coatings. Among these coatings, Ni–TiO₂–9C coating exhibited the highest water contact angle of 157°.     

电沉积Ni-S-Co/ZrO_2复合电极及其催化析氢性能

在镀液中悬浮粒径为200～400 nm的ZrO2固体颗粒,以电沉积方法制备了Ni-S-Co/ZrO2复合电极。XRD和SEM测试结果表明,沉积层由非晶态的Ni、Co、S和单斜晶型的ZrO2粒子组成。镀层表面呈团粒状结构,无裂隙,与基体结合牢固。电化学测试结果表明,25℃时,Ni-S-Co/ZrO2复合电极在质量分数28%NaOH水溶液中,在电流密度100 mA/cm2下的超电势为145 mV,与未复合纳米ZrO2粒子的Ni-S-Co电极相比降低了50 mV。表明超细ZrO2的掺入有效提高了电极对析氢反应的催化效果。实验表明,沉积的最佳电流密度为70 mA/cm2,最适宜的ZrO2用量为15 g/L,采用Ni-S-Co作为过渡层可以显著改善复合镀层与基体的结合。     

Ni-SiO2纳米微粒复合镀层的电沉积及其耐蚀性研究

采用控电流电沉积技术以铜为基体制备了Ni-SiO2纳米微粒复合镀层.通过改变镀液中SiO2纳米微粒的质量浓度,考察了其对镀层中SiO2微粒的质量分数、电沉积速率及镀层耐蚀性能的影响,对纯镍镀层与Ni-SiO2纳米微粒复合镀层的耐蚀性进行了比较.研究了阴极电流密度对复合镀层耐蚀性能的影响,并采用扫描电子显微镜对镀层形貌进...