Ni-P-纳米金刚石化学复合镀研究

采用制备的粒度150 nm以内的复合镀用纳米金刚石悬浮液进行了Ni-P-纳米金刚石化学复合镀研究,研究了工艺条件包括纳米金刚石加入量、搅拌方式、离子型和非离子型表面活性剂及其组合的加入对复合镀镀速和镀层性能的影响。结果表明:纳米化学复合镀要求镀液有更好的稳定性;镀速与搅拌方式有关,并且随纳米金刚石的加入而提高;组合型表面活性剂对复合镀层性能提高明显;表面形貌分析观察到镀层中纳米金刚石分布均匀,颗粒在100~200 nm左右。     

化学镀(Ni-P)-SiC纳米复合镀层性能研究

利用化学镀方法获得了(Ni-P)-Si C纳米微粒复合镀层,并研究了Si C颗粒含量、p H及热处理等条件对镀层硬度及耐磨性的影响。扫描电镜测试表明,镀层表面平整,Si C纳米颗粒均匀复合于镀层中。镀层的硬度与耐磨性能测试表明,随着镀液中Si C含量的增加,复合镀层的硬度与耐磨性先升高后降低。当镀液中Si C质量浓度为10 g/L时,镀层硬度及耐磨性最好,热处理后的镀层硬度高达1069 HV。     

中国专利

环保型纳米复合增强耐磨镀层生成液 本发明公开了一种环保型纳米复合增强耐磨镀层生成液,该镀层生成液不依靠电场力就可以在金属机件表面上生成一层由镍．磷纳米硬质陶瓷微粒组成的耐磨镀层。本发明与电镀硬铬相比具有成本低、耗能低、不污染环境的特点,特别是高性能纳米陶瓷共沉入合金镀层晶格中,大大增强了镀层的综合耐磨性能,比电镀硬铬层耐磨性提高了5倍以上。可替代电镀硬铬层对金属机件进行表面强化处理。     

表面活性剂对镍-铁-石墨烯复合镀层的影响

采用复合电镀的方法在7075铝合金上制备了镍-铁-石墨烯复合镀层,研究了不同种类、不同添加量的表面活性剂对镀液中石墨烯的分散性及复合镀层硬度、耐磨性的影响。采用SEM、EDS、XRD、Raman对复合镀层的结构形貌进行了表征。研究结果表明:与未添加表面活性剂的镍-铁-石墨烯复合镀层(硬度为823.9(HV),摩擦系数为0.1999)相比,添加石墨烯质量的80%的阴离子表面活性剂十二烷基硫酸钠(SDS)有利于石墨烯在复合镀液中的分散,能够显著地提高复合镀层的硬度和耐磨性能,其硬度提高了13.38%,摩擦系数降低了26.11%。     

化学复合镀中金刚石颗粒的分散对复合镀层性能的影响

通过数值仿真,研究了镀槽结构与搅拌速率对镀液流场和镀液中金刚石颗粒分布特性的影响,并制备了镍–磷–金刚石复合镀层,研究了镀槽结构与搅拌速率对镀层中金刚石含量、粒径分布以及镀层显微硬度和耐磨性的影响。结果表明,镀槽中添加挡板和提高搅拌速率,可以明显改善镀液流场的均匀性,有利于金刚石颗粒在镀液与镀层中的分散与均匀分布,显著提高复合镀层的显微硬度与耐磨性;当镀槽中有挡板、搅拌速率为600 r/min时,所制备的微米金刚石–镍–磷复合镀层经400°C热处理1 h后,显微硬度高达1 442 HV,镀层几乎无磨损。     

镍-磷微米金刚石化学复合镀工艺及镀层性能

采用化学复合镀法在低碳钢表面镀覆Ni–P–金刚石复合镀层。化学镀基础镀液含硫酸镍25g/L、次磷酸钠25g/L、结晶乙酸钠15g/L和柠檬酸钠10g/L,pH为4～5,温度80～85°C。金刚石颗粒的平均粒径为5μm。比较了直接复合镀及两步复合镀工艺分别所得镀层的微观形貌。借助材料表面微纳米力学测试仪及磨损试验机研究了复合镀层的性能。先化学镀Ni–P合金30min,然后在机械间歇搅拌下加入金刚石0.4g/L,再复合镀10min,可使金刚石颗粒均匀地镶嵌在镍基镀层中,并有一部分凸出镀层表面,从而增大了镀层的摩擦因数及与GCr15相对面的咬合力。金刚石复合镀层的干摩擦因数可达0.518。动载条件下未出现脱落现象。     

中温酸性纳米化学复合镀镍-磷-石墨工艺

采用化学复合镀方法在45钢基体上镀覆Ni–P–石墨复合镀层,通过改变镀液的pH、搅拌速度、表面活性剂和石墨(40nm)的用量,优化了化学复合镀工艺,确定了较优的工艺参数:石墨粒子240mg/L,表面活性剂(十二烷基苯磺酸钠)0.05g/L,pH5.0,搅拌速率300r/min。以扫描电镜和能谱分析了优化工艺获得的Ni–P–石墨复合镀层的表面形貌及组成,测试了镀层性能。结果表明,Ni–P–石墨复合镀层中石墨分散均匀,Ni和P的质量分数分别为93.78%和6.22%。与Ni–P合金镀层相比,Ni–P–石墨复合镀层的耐蚀性明显提高,其耐磨性提高了5倍,热处理后复合镀层的显微硬度最大可以达到1336.3HV。     

表面活性剂对ZL102表面镍–磷–碳化硅化学复合镀的影响

在酸性化学镀镍液中分别加入阴离子型、阳离子型和非离子型9种表面活性剂,以分散SiC微粒并在ZL102铝合金表面制备性能良好的Ni–P–SiC复合镀层。通过研究表面活性剂对镀液性能和复合镀层表面形貌、显微硬度、孔隙率及SiC复合量的影响,对表面活性剂进行筛选。结果表明,以60mg/L聚乙二醇作表面活性剂时,SiC微粒的分散效果最好,所得Ni–P–SiC复合镀层的孔隙率仅为0.5714个/cm2,显微硬度为729.76HV,镀层中的SiC颗粒细小、分布均匀,复合量达5.00%,综合性能最好。     

(Zn-Co)-TiO_2纳米复合镀层的制备及耐蚀性能的研究

利用纳米复合电沉积方法在低碳钢基体上制备了(Zn-Co)-TiO2纳米复合镀层。分析了镀液中纳米TiO2含量、表面活性剂十六烷基三甲基溴化铵质量浓度、电流密度以及温度对镀层中Co、纳米TiO2含量的影响,得出制备(Zn-Co)-TiO2纳米复合镀层的最优工艺条件:60g/L纳米TiO2、1.0 g/L表面活性剂十六烷基三甲基溴化铵、Jκ为4A/dm2、θ为55~60℃。通过扫描电镜、极化曲线对镀层的形貌特征及耐蚀性能进行了分析。结果表明,纳米复合镀层表面完整,没有明显的缺陷;TiO2均匀地分布在Zn-Co合金镀层中,进一步提高了镀层的耐蚀性能。     

镍磷纳米化学复合镀中纳米二氧化钛的分散性研究

利用X射线光电子能谱仪(XPS)分析了不同纳米Ti O2含量的Ni–P化学镀液所制备的Ni–P–TiO 2复合镀层中纳米TiO 2的含量及其分布状况,在以乳酸为配位剂、聚乙烯吡咯烷酮(PVP)为表面活性剂的Ni–P–Ti O2化学复合镀液中,采用红外–可见–紫外分光光度法研究了不同用量的乳酸和PVP以及镀液p H对纳米Ti O2分散性的影响,获得了最佳的分散条件:纳米Ti O2加入量3.0~4.0 g/L,PVP 0.2 g/L,乳酸4.5 m L/L,p H 5.0~5.5。     

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).     

金刚石化学镀镍预处理工艺的改进

为了改进金刚石切割片中的树脂结合剂与磨粒之间相互的粘结程度,以希望达到覆着刺状金属层效果,文中对金刚石化学镀的预处理工艺进行了优化改进。采用了将金刚石粉末加入铬酸洗液中进行浸泡11 h的亲水处理,选择了离子钯活化液实现活化处理。实验结果表明:未经亲水化处理的镍-磷镀层,部分晶面出现漏层现象,而亲水处理过的镀层无此现象;改进工艺能够实现凹凸不平的较厚的镀层的形成;酸性镀液的沉积速率相对较快,但采用该镀液获得的镀层的形貌大都平整光滑,很少出现刺状镀层,碱性镀液沉积速率虽然较低,但施镀温度低,镀液络合稳定常数较高,镀液更稳定,且在碱性镀液中更容易实现人造金刚石表面的刺状镀层的获得。     

Ni-P-PTFE自润滑镀层的耐磨性能及其增强机理研究

采用化学复合镀技术将纳米聚四氟乙烯(PTFE)微粒沉积到化学镀Ni-P镀层中。扫描电镜(SEM)表明:镀层内PTFE微粒分散均匀,与Ni-P镀层结合紧密。摩擦磨损实验表明:在100N作用下,Ni-P-PTFE镀层的摩擦因数约为0.03,具有良好的摩擦学性能。热处理后的摩擦磨损实验表明:经热处理后,镀层仍具有较低的摩擦因数和良好的耐磨性能。     

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.     

CeO_2对AZ 91D合金化学复合镀Ni-P-CeO_2的影响

在AZ 91D合金上化学镀Ni-P的镀液中添加CeO2,以获得N-p-CeO2复合镀层.实验结果表明:稀土的质量浓度增加可使镀层的沉积速率降低,CeO2的质量浓度为0.10 g/L时,效果最佳;热处理后镀层中形成了Mg17Ce2,Ni3P,Ce2Ni7新相;相对AZ 91D合金,Ni-p-CeO3镀层的耐磨性提高了25.78倍,耐盐腐蚀提高了8.26倍,耐酸腐蚀提高了12.79倍.     

锦纶织物复合化学镀(Ni-P)-Si3N4纳米微粒复合镀层

采用纳米复合化学镀技术,分别于酸性和碱性镀液中在锦纶织物表面沉积了(Ni-P)-Si3N4复合镀层,对镀层表面形貌、结构和织物热性能进行了表征,并测试了化学镀织物的电磁波屏蔽和耐磨性能.研究结果表明,Si3N4纳米微粒的引入使酸性复合化学镀(Ni-P)-Si3N4镀层无定形态有所增强,碱性复合化学镀(Ni-P)-Si3...     

镁合金化学复合镀Ni-P/纳米SiC工艺的研究

在AZ 91D镁合金表面制备Ni-P/纳米SiC化学复合镀层.探讨镀液中纳米SiC微粒的质量浓度对镀速、复合镀层性能等的影响.利用扫描电镜观察镀层表面形貌,采用能谱分析仪进行镀层表面成分的定性分析,采用显微硬度计测试镀层硬度,并对不同工艺下获得的镀层进行快速磨损实验.结果表明:镀液中添加适量的纳米SiC微粒,镀速和镀层硬度都有显著的提高.当镀液中纳米SiC的质量浓度为9 g/L时,镀速可达到25.6 μm/h;当镀液中纳米SiC的质量浓度为7 g/L时,镀层的维氏硬度可达到9 380 MPa;同时镀层的耐磨性能相比于Ni-P合金镀层的也有显著提高.     

Tribological application of carbon nanotubes in a metal-based composite coating and composites

Ni-P-carbon nanotube (CNT) composite coating and carbon nanotube/copper matrix composites were prepared by electroless plating and powder metallurgy techniques, respectively. The effects of CNTs on the tribological properties of these composites were evaluated. The results demonstrated that the Ni-P-CNT electroless composite coating exhibited higher wear resistance and lower friction coefficient than Ni-P-SiC and Ni-P-graphite composite coatings. After annealing at 673 K for 2 h, the wear resistance of the Ni-P-CNT composite coating was improved. Carbon nanotube/copper matrix composites revealed a lower wear rate and friction coefficient compared with pure copper, and their wear rates and friction coefficients showed a decreasing trend with increasing volume fraction of CNTs within the range from 0 to 12 vol.% due to the effects of the reinforcement and reduced friction of CNTs. The favorable effects of CNTs on the tribological properties are attributed to improved mechanical properties and unique topological structure of the hollow nanotubes.     

(Ni-P)-TiO2复合化学镀层的制备

将TiO2颗粒引入Ni-P合金镀液,采用化学镀的方法在黄铜上制备了(Ni-P)-TiO2复合镀层.利用扫描电镜、X-射线能谱仪、X-射线衍射仪和比表面积测试等检测手段,对(Ni-P)-TiO2复合镀层的形貌、化学组成、相结构以及其比表面积进行了分析.研究结果表明:(Ni-P)-TiO2镀层表面为均匀分布绒丝状复合物;T...