镍基及镍合金纳米复合电刷镀的研究进展

镍基及镍合金纳米复合刷镀层因具有优异的耐磨损、耐高温、耐腐蚀性能,已成为纳米复合电刷镀技术的主攻方向,受到国内外的广泛关注。综述了近年来,镍及镍钨合金、镍钴合金、镍铁合金、镍钼合金纳米复合刷镀层的研究现状。指出目前纳米复合电刷镀技术研究的局限是镀层基质偏重镍基,镀液所添纳米颗粒种类有限,镀层所含纳米颗粒单一、复合量低,镀层性能提升空间有限。纳米颗粒的种类、含量、尺寸与纳米颗粒硬质点强化效应的定量关系以及基于电刷镀工艺特点的复合电沉积机理,研究进展缓慢,是今后纳米复合电刷镀研究的难点。镍合金纳米复合刷镀层、多粒子纳米复合刷镀层、特殊功能纳米复合刷镀层、宽范围纳米颗粒复合量刷镀层的研究,将会赋予人们控制材料性能更大的主动性,是未来纳米复合电刷镀研究的重要方向。     

电刷镀WCp/Ni复合镀层组织与磨损特性

采用电刷镀技术制备了含有微米WC/Ni复合镀层,分析了该复合镀层的微观组织,测试了该镀层的显微硬度和摩擦磨损性能,研究了微米颗粒沉积量对镀层摩擦磨损性能的影响.结果表明,随着镀液中WC颗粒含量的增加,复合镀层的组织趋于细化,WC/Ni复合镀层较快镍镀层具有更高的显微硬度和良好的耐磨性,含量在30 g/L时达到最大.     

电刷镀WC_p/Ni复合镀层组织与磨损特性

采用电刷镀技术制备了含有微米WC/Ni复合镀层,分析了该复合镀层的微观组织,测试了该镀层的显微硬度和摩擦磨损性能,研究了微米颗粒沉积量对镀层摩擦磨损性能的影响。结果表明,随着镀液中WC颗粒含量的增加,复合镀层的组织趋于细化,WC/Ni复合镀层较快镍镀层具有更高的显微硬度和良好的耐磨性,含量在30 g/L时达到最大。     

n-Al2O3/Ni复合电刷镀层滑动磨损性能

为了提高材料在含磨粒油润滑条件下的摩擦磨损性能，制备了n-Al2O3／Ni电刷镀复合镀层，采用扫描电镜观察了镀层的表面和截面组织以及纳米颗粒在复合镀层中的分布，以GCr15钢为对摩件对比了复合镀层与快速镍刷镀层以及45钢的摩擦磨损性能，并且对磨损试样表面的形貌和成分进行了分析。结果发现，纳米颗粒的加入细化了镀层组织，改善了镀层与基体的结合，提高了镀层的硬度；材料在含细沙油润滑条件下的磨损量与时间呈线性关系，复合镀层的摩擦系数和磨损量小于快速镍镀层和45钢。     

滑动速度对纳米颗粒复合镀层摩擦性能的影响

采用电刷镀技术在45钢表面制备了纳米Al2O3颗粒复合镀层,并且在球-盘式肇擦磨损试验机上对比研究了纳米颗粒复合镀层与普通快速镍镀层在含污染物油润滑条件下的摩擦磨损性能。结果表明纳米颗粒复合镀层的摩擦系数和磨损量均小于快速镍镀层。随滑动速度增加,两种镀层磨损量都先减少后增加,但纳米颗粒复合镀层磨损量增加的幅度小于快速镀镍层c两种镀层的磨损机理均为磨粒磨损和粘着磨损。由于纳米颗粒的强化作用,复合镀层的耐磨性优于快速镀镍层。     

纳米Al2O3颗粒含量对复合镀层组织和滑动磨损行为的影响

采用电刷镀技术在45钢表面制备了纳米Al2O3颗粒增强镍基复合镀层，研究了纳米Al2O3颗粒在镀液中的含量对镀层的组织、力学性能和摩擦学性能的影响，并分析探讨了影响机理。结果表明，随着镀液中纳米Al2O3颗粒含量的增加，复合镀层的组织趋于细化，在含量为20g／L时复合镀层的硬度和耐磨性出现极值，其磨损机制也随之发生改变，这与纳米Al2O3颗粒在复合镀层中的含量和分布状态密切相关。     

Ni-TiO2基纳米复合电刷镀层微观结构及腐蚀电化学行为

研究了用电刷镀在Q235钢上制备出Ni-TiO2纳米复合镀层复合镀液中,纳米颗粒的加入量及不同的表面活性剂对镀层性能的影响。采用SEM对复合镀层的表面形貌进行分析,用极化曲线研究了纳米复合镀层在NaCl溶液中的腐蚀电化学行为,结果表明:与纯Ni镀层相比,Ni-TiO2纳米复合镀层晶粒更加细小,空隙率更低,阳离子表面活性剂分散镀液所得镀层效果最为显著;复合镀液中纳米TiO2质量浓度为10g/L时,复合镀层的耐腐蚀性能最优;纳米颗粒含量相等的情况下,阳离子表面活性剂分散镀液所得镀层具有最好的耐腐蚀性能。     

结晶器铜板表面耐磨纳米复合镀层的制备及性能

目的提高连铸坯质量,延长结晶器的服役时间,节约铜资源。方法采用纳米复合镀技术在结晶器铜板表面制备了Ni/Al_2O_3纳米复合镀层,并通过扫描电镜(SEM)观察了复合镀层表面形貌。采用单因素变量法研究了镀液中纳米Al_2O_3添加量、阴极电流密度及镀液温度等对纳米复合镀层显微硬度的影响。对结晶器铜板表面的纯Ni镀层和纳米复合镀层进行了摩擦磨损实验。结果在结晶器铜板表面制备出了高硬度、耐磨损的纳米复合镀层。随着镀液中纳米颗粒添加量的增加,镀层的硬度先升高后降低,且当纳米颗粒添加量为40 g/L时,复合镀层的显微硬度达到最大值384HV。因镀液中纳米颗粒的存在,随着电流密度和镀液温度的变化,纳米复合镀层的硬度变化不大。在相同的摩擦磨损条件下,纳米复合镀层和纯Ni镀层的摩擦系数分别约为0.41和0.7,纳米复合镀层的磨损量约为纯Ni镀层的1/2。结论在Ni基镀层中加入纳米Al_2O_3材料,能显著地提高复合镀层的硬度、耐磨损性能。     

表面活性剂和纳米PTFE对Ni-P-PTFE镀层力学和摩擦学性能的影响

在化学沉积Ni-P镀层的工艺基础上,通过改变镀液中添加的表面活性剂和纳米PTFE的含量,制备了Ni-P-PTFE复合镀层,并研究了镀液中表面活性剂和纳米PTFE的含量对复合镀层的力学和摩擦学性能的影响.研究结果表明:当镀液中的表面活性剂和纳米PTFE添加量均为6 g/L时,所得的Ni-P-PTFE复合镀层PTFE含量较高,具有优良的力学和摩擦学性能,其磨损机制主要为粘着磨损,并伴随轻微的磨粒磨损.     

纳米WC和纳米PTFE的复合镀层微拉伸研究

采用电刷镀技术在高速钢W6Mo5Cr4V2材料上制备了纳米WC和纳米FFFE复合镀层.采用S-2700型扫描电子显微镜(SEM)、X-射线衍射仪和显微硬度计分析了不同纳米PTFE含量的纳米复合镀层的表面形貌、组织结构和显微硬度.同时,通过在扫描电镜下的微拉伸试验来测定不同含量纳米PTFE和WC的纳米复合镀层的应力-应变曲线.试验结果表明:随着纳米PTFE的加入含量增加,纳米复合镀层的组织逐渐细化和致密;当纳米PTFE含量超过5 g/L后,组织致密度开始下降.显维硬度也反映了先升高再下降的过程.纳米复合镀层的抗拉强度随着纳米WC和纳米PTFE含量的增加而增加,但其作用影响有逐渐减弱的作用.纳米复合镀层的组织主要由纳米颗粒和镍基体相组成.     

Ni-W/SiC纳米复合镀层的制备与其耐蚀性

通过电沉积方法制备了Ni-W/SiC纳米复合镀层,利用扫描电子显微镜(SEM)、能谱分析(EDS)和X射线衍射分析(XRD)研究了SiC含量对该复合镀层结构和性能的影响,采用电化学方法研究了Ni-W/SiC纳米复合镀层在质量分数为3.5%NaCl溶液中的耐蚀性。结果表明:SiC纳米颗粒能促进镀层晶粒的形核及生长,显著改变镀层的晶体结构,提高镀层的硬度、耐磨性及耐蚀性;SiC含量过低对镀层耐磨性提高有限,含量过高又容易导致SiC纳米颗粒团聚,影响其分散性,因此当SiC的质量浓度为6~9g/L时所制备的Ni-W/SiC纳米复合镀层具有最佳的性能。     

氧乙炔火焰喷焊镍基复合涂层的显微组织和腐蚀性能研究

目的 研究Ni60和Ni60WC喷焊涂层的显微组织、防腐和耐磨性能及其腐蚀机理,为恶劣工况下服役的零件选择合适的喷焊涂层提供参考.方法 采用氧乙炔火焰喷焊工艺在16Mn钢基体上制备Ni60和Ni60WC涂层,用X射线衍射仪、金相显微镜和扫描电子显微镜分析了喷焊涂层的相结构和显微组织,并采用电化学工作站、盐雾腐蚀试验机、磨粒磨损试验机测试了两种喷焊涂层的防腐和耐磨性能.结果 喷焊层与基体间都存在冶金结合层和热影响区,Ni60涂层的显微组织为NiCr固溶体基体上弥散分布着大量细小粒状和杆状碳化物和硼化物.Ni60WC喷焊涂层组织中,除了具有与Ni60涂层类似的基体相和细颗粒硬质相外,还较均匀地分布着不同尺寸的WC颗粒.Ni60和Ni60WC涂层的磨损率分别为16Mn钢的8.3％和2.3％,自腐蚀电流密度分别为16Mn钢的1.0％和7.6％.另外,基体相和硬质相之间的电偶腐蚀是两种镍基喷焊涂层的主要腐蚀机理.结论 这两种镍基喷焊涂层均能显著提高16Mn钢的抗磨和防腐性能,其中,Ni60喷焊涂层耐腐蚀性更好,Ni60WC喷焊涂层耐磨损性能更好.     

Preparation and Mechanical Properties of Electroless Nickel-Phosphorus-Tungsten Carbide Nanocomposite Coatings

Ni-P-WC nanocomposite coatings were prepared successfully in the electroless bath containing WC nanoparticles. The influences of WC nanoparticles concentration, stirring speed, and temperature of plating bath on the WC weight percentage in the Ni-P-WC nanocomposite coatings were investigated. The microhardness and wear resistance of Ni-P-WC nanocomposite coatings were evaluated, respectively. The results show that the incorporation of WC nanoparticles in composite coatings elevates the wear resistance and microhardness. The friction coefficient and wear loss of Ni-P-WC nanocomposite coatings decrease with the increase of WC weight percentage, while the microhardness increases with the increase of WC weight percentage.     

Water-Lubricated Ni-Based Composite(Ni-Al_2O_3,Ni-SiC and Ni-ZrO_2)Thin Film Coatings for Industrial Applications

In this work,pure nickel and Ni-based nanocomposite coatings(N1-Al_2O_3,Ni-SiC and Ni-ZrO_2) were produced on steel substrate by using pulse electrodeposition technique.The industrial performance tests were conducted to evaluate the wear resistance,corrosion resistance,adhesion strength and wettability behaviour of newly developed coatings.Rolling contact ball-on-disc tribometer was used to assess anti-wear behaviour of these coatings under waterlubricated contacts.The results showed that the wear- and corrosion resistance properties of nickel alumina and Ni-SiC composite coatings significantly improved than that of pure Ni and Ni-ZrO_2 coatings.The adhesion and wettability results of Ni-Al_2O_3 composite showed better performance when compared to the rest of the coatings.The effects of incorporating nanoparticles on the surface microstructure,interface adhesion and distribution of the particles were also investigated.The coatings were characterized by using scanning electron microscopy,X-ray diffraction analysis and 3D white light interferometry.The wear failure behaviour of these coatings was further examined by post-test surface observation under optical microscope.     

纳米Cr2O3复合电刷镀镀层性能研究

在快速镍镀液的基础上,通过添加纳米Cr2O3粉末得到了纳米复合镀液,制备了纳米Cr2O3颗粒的镍基复合镀层,通过显微硬度、孔隙率、耐腐蚀与极化曲线、SEM等测试手段,比较了纳米复合镀层与纯镍镀层的性能,结果表明：纳米Cr2O3复合刷镀镍层的截面硬度比纯镍镀层的截面硬度提高8.3%,两种镀层与基体结合良好;纳米Cr2O3复合镀层的表面形貌比纯镍镀层更加细化且耐腐蚀性有所提高。     

Relationship between dispersibility of ZrO2 nanoparticles in Ni-ZrO2 electroplated nanocomposite coatings and mechanical properties of nanocomposite coatings

Ni-ZrO2 nanocomposite coatings with monodispersed ZrO2 nanoparticles were prepared from the composite plating bath containing dispersant under DC electrodeposition condition. It is found that the morphology, orientation and hardness of the composite coating with monodispersed ZrO2 nanoparticles have lots of difference from the composite coating with agglomerated ZrO2 nanoparticles and pure nickel coating. Especially, the result of hardness shows that only a very low volume fraction (less than 1%) of monodispered ZrO2 nanoparticles in Ni-ZrO2 composite coatings will result in higher hardness of the coating. The hardness of Ni-ZrO2 nanocomposite coatings with monodispersed and agglomerated ZrO2 nanoparticles are HV 529 and HV 393, respectively. The hardness value of the former composite coatings is over 1.3 times higher than that of the later. All these composite coatings are 2 - 3 times higher than that of pure nickel plating (HV 207) prepared under the same conditions.     

粒径对电沉积Ni-SiC复合镀层性能的影响

采用复合电沉积的方法,在一定的工艺条件下制备出Ni-SiC复合镀层。通过摩擦磨损试验、电化学腐蚀试验,并利用扫描电镜观察镀层的磨损和腐蚀形貌,综合分析了SiC颗粒大小对镀层性能的影响。结果表明：当SiC粒径为2μm,添加量为60 g.L-1时,镀层的显微硬度最高,耐磨性能最佳;复合镀层的耐蚀性比纯镍镀层和钢基体优越,但随着SiC粒径的增大,镀层的耐蚀性反而有所下降。     

系泊缆用22MnCrNiMo钢表面纳米复合镀层的制备

目的制备性能良好的Ni-SiC复合镀层,以提高海洋平台系泊缆用22MnCrNiMo钢的耐腐蚀性和寿命。方法采用基于离心力的双脉冲电沉积技术,在海洋平台系泊缆用22MnCrNiMo钢表面制备Ni-SiC纳米复合镀层。通过扫描电子显微镜和光学显微镜对复合镀层的微观形貌、组织结构进行分析。利用静态浸泡腐蚀试验分析了镀层的耐腐蚀性能。结果添加0.2g/L的SDS时,纳米SiC悬浮液具有最佳悬浮性能。纳米SiC颗粒的质量浓度为2.0~4.0g/L时,有利于获得优异的Ni-SiC镀层表面形貌。随着占空比的增加,复合镀层表面的晶粒尺寸逐渐减小,当占空比为50%时,可以获得最佳的Ni-SiC镀层形貌。当添加2.0g/L的纳米SiC颗粒时,镀层的腐蚀质量损失最小,为2.867mg/cm~2;当占空比为50%时,镀层的腐蚀质量损失最小,为3.059mg/cm~2。结论添加分散剂后,镀液中的纳米SiC颗粒沉降性能变好;添加纳米SiC颗粒后,镀层的耐腐蚀性能增强。纳米SiC颗粒的添加量和占空比的大小对复合镀层的组织结构和耐腐蚀性能有重要影响。     

Microstructure and Sliding Wear Resistance of Laser Cladded WC/Ni Composite Coatings with Different Contents of WC Particle

The aim of this article was to address the effect of WC content on the microstructure, microhardness, and sliding wear resistance of laser cladded WC/Ni composite coatings. The content of WC particle in the feed powder varied in the range of 0-80 wt.%. Experimental results showed that the laser cladded coatings exhibited homogeneous microstructure without pores or cracks. By comparing with the 45# steel substrate, the microhardness of WC/Ni composite coatings was relatively high. The microhardness of coating increased with increasing the content of WC particles. The wear resistance of WC/Ni composite coatings was strongly dependent on the content of WC particle and their microstructure. When the WC content was lower than 40 wt.% in the feed powder, the wear rate of the coatings decreased with increasing WC content. The two-body abrasive wear was identified as the main wear mechanisms. For the coatings with WC content higher than 40 wt.% in the feed powder, their wear rate increased with increasing WC content. The three-body abrasive wear and fatigue wear were the main failures. The coating with 40 wt.% WC in the feed powder exhibited the best wear resistance.