Ni-Al2O3纳米复合电镀工艺的初步研究

初步研究了复合电镀各工艺条件：电流密度、镀液pH值和温度以及搅拌方式对Al2O3纳米微粒在镍基复合镀层中含量的影响。研究表明：电流密度增大不利于提高镀层中纳米微粒的含量；pH值增大也明显使复合量降低;镀液温度升高，镀层中微粒的复合量随之略有改变；电镀时，加强搅拌或适当改变搅拌方式，可以使复合镀居中的纳米微粒含量提高。还利用扫描电镜及能谱对Ni-Al2O3镀层表面进行了观察与分析。     

低温熔盐电沉积羟基磷灰石复合涂层的研究

为了提高羟基磷灰石涂层的结合强度,在AlCl3-NaCl-TiCl3低温熔盐体系中加入HA微粒,复合电沉积制备Al-Ti/HA复合涂层,并对涂层的表面形貌、结构和结合强度进行了研究.结果表明: HA微粒均匀分散在Al-Ti合金镀层中,其共沉积量随电流密度的减小和熔盐中HA浓度的增大而增强;涂层的结合强度随HA共沉积量的增大而增强,当HA的共沉积量为40.1%(质量分数)时,Al-Ti/HA复合涂层的结合强度达到28.1 MPa.     

非晶态Ni-W-WC复合镀层的制备及镀层性能研究

在非晶态Ni—W合金镀液中加入WC微粒，采用复合电沉积工艺制各非晶态Ni—W—WC复合镀层，井考察了复合镀层在碱性介质中的电催化析氢性能。结果表明，复合镀层中WC微粒的含量随镀液中WC微粒的浓度和电流密度的增加而增加；加入WC微粒后所获得的复合镀层仍然是非晶态结构；复合电板的电催化析氢性能明显优于Ni—W合金电板，性能的提高与其较高的比表面积和较低的析氢反应标准活化自由能有关。     

Ni-Fe-NiFe_2O_4电沉积层的制备及其性能

在镀液中添加铁氧体粒子制备Ni-Fe基磁性复合镀层是电沉积技术一个新的发展方向,目前相关研究不多。采用电沉积法在铜片上制备了Ni-Fe-NiFe2O4复合镀层,用电化学方法、金相显微镜及能谱仪研究了镀液中NiFe2O4含量、电流密度、表面活性剂十六烷基三甲基溴化铵(CTAB)等对复合镀层性能的影响。结果表明:复合镀层硬度随镀液中NiFe2O4含量的增加先增大后减小,含量为15 g/L时镀层硬度达370 HV,耐蚀性最好;随电流密度增大,沉积速率加快,镀层显微硬度增加,耐蚀性略有提高;加入CTAB能提高镀层中微粒的复合量,可在较低的电流密度下获得孔隙小、致密度高的镀层,显微硬度也有所提高,但耐蚀性略有下降;在温度为60℃,镀液中NiFe2O4含量为15 g/L,电流密度为5 A/dm2,CTAB含量为0.1%(质量分数)时,可获得性能较好的复合镀层,镀层中NiFe2O4含量较高,均匀致密,微观表面粗糙,无裂纹,与基体结合良好。     

n-Al2O3P/Ni复合刷镀层的组织和摩擦磨损特性

研究了镍基纳米Al2O3复合电刷镀层（n-Al2O3^p/Ni）的组织特征及擦磨损特性，并与快镍刷镀（Ni)进行了比较。结果表明：n-Al2O3^p/Ni复合刷镀层表面粗糙度更小，组织更致密，镀层摩擦系数随镀液中纳米粒子含量增加稍有增大；n-Al2O3在复合刷镀层中弥散分布，与基相良好结合；复合镀的耐磨性能明显优于Ni刷镀层，镀液中n-Al2O3含量为20g/L时，复合刷镀层具有最佳耐磨性能。     

（Ni—W）—SiC复合镀层的研制

本文报道了制备（Ni-W)-SiC复合镀层的电沉积工艺，获得了含碳化硅1．1％－8．3％，含钨47．2％－51．0％的（Ni-W)-SiC复合镀层，讨论了微粒悬浮量、温度、pH值，阴极电流密度对镀层中碳化硅含量的影响，测试了复合镀层的硬度及耐磨性，结果表明，SiC微粒的复合，明显增加了Ni-W合金镀层的硬度和耐磨性能。     

Ni-P-SiC-MoS2化学复合镀层的组织结构及耐磨性能

在Ni-P化学镀液中添加第二相粒子可提高镀层性能,但目前已有的此类研究中镀层性能还不甚理想。在35CrNi钢基体上沉积了Ni-P-SiC-MoS2复合镀层,借助扫描电镜(SEM)、能谱仪、显微硬度计、磨损试验机等分析了复合镀层的表面形貌、成分、硬度及耐磨性。结果表明:Ni-P-SiC-MoS2镀层为非晶态结构;镀层硬度随SiC和MoS2混合微粒含量的增加而增加,随热处理温度的升高先升后略降;添加SiC和MoS2的混合微粒6g/L的镀层摩擦磨损性能最好。     

电沉积Ni-P非晶纳米SiC复合镀层的工艺研究

为了提高非晶镀层的硬度,在Ni-P镀液中加入高硬度、高耐磨性的纳米微粒SiC,采用电沉积方法制备了Ni-P非晶纳米SiC复合镀层.研究了工艺温度、电流密度和镀液中SiC浓度对非晶纳米复合镀层中P含量和SiC纳米颗粒分布的影响,并用扫描电镜对镀层表面进行了观察,通过纳米显微力学探针测量了镀层硬度.结果表明:随电流密度增大和镀液中SiC含量的增加,镀层中纳米SiC的复合量增加;镀液温度在60℃时,镀层中SiC含量最大,复合镀层的硬度显著提高,可达到7.4 GPa,比普通的Ni-P非晶镀层大为提高.     

SiC含量和电流密度对Ni—SiC镀层耐磨性的影响

研究了镀液中ＳｉＣ含量对镀层中ＳｉＣ含量的影响以及镀层中ＳｉＣ含量和电流密度对镀层硬度和耐磨性的影响。试验结果表明，随度层中ＳｉＣ含量的增加，镀层硬度增加；随镀层中ＳｉＣ含量和电流密度增加，耐磨性增大到极大值后又下降。     

强磁场下Ni/Al2O3纳米复合镀层制备及性能

施加强磁场用直流电镀法在Q235钢基体上成功制备了Ni／Al2O3纳米复合镀层．结果表明，随着磁感应强度的增大，镀层中纳米微粒含量增加，形成的纳米复合镀层均匀致密；当磁感应强度为8．0T时，所得复合镀层的硬度比纯镍镀层提高2．3倍，而磨损率仅为纯镍镀层的24．5％．磨损表面形貌分析表明纯镍镀层的磨损机制为黏着磨损，而纳米复合镀层的磨损机制为磨粒磨损．强磁场通过洛仑兹力导致的磁流体动力使镀液产生涡流，宏观上形成对流，对镀液起搅拌作用，进而影响镀层性能．     

The running-in tribological behavior of nano-SiO2/Ni composite coatings

The running-in tribological behavior of the electrodeposited nano-SiO₂/Ni composite coatings is investigated using an M-200 block-on-wheel friction and wear tester. The results show that the electrodeposited nano-SiO₂/Ni composite coatings exhibit good wear resistance in the running-in period. With increasing nano-SiO₂ particle content in the electrodeposition plating solution, the wear resistance of the composite coatings are first improved and then decreased slightly, and the friction coefficient decreases first and then increased. If the nano-SiO₂ particle content in electrodeposition plating solution is 10 g/L, the composite coatings show the best wear resistance.     

脉冲电沉积RE-Ni-W-B-PTFE-Al2 O3复合镀层性能的研究

高性能复合镀层具有优良的耐磨、耐蚀性能,能满足工业生产对材料性能的要求.研究了脉冲电沉积RE-Ni-W-B-PTFE-Al2O3复合镀层的成分、形貌及性能.结果表明:脉冲电流及Al2O3固体颗粒能明显提高RE-Ni-W-B-PTFE-Al2O3复合镀层中W和B的含量;与直流电沉积相比,脉冲电沉积RE-Ni-W-B复合镀层的表面裂纹已明显减小,但裂纹仍存在,当Al2O3耐磨颗粒及PTFE减摩微粒嵌入RE-Ni-W-B复合镀层中以后,在SEM 400倍下观察,RE-Ni-W-B-PTFE-Al2O3镀层已不存在裂纹, 而且镀液中Al2O3颗粒含量越多,晶粒就越细;此外,研究表明,镀液中Al2O3颗粒含量增加, RE-Ni-W-B-PTFE-Al2O3复合镀层镀态硬度增加,磨损率降低.     

The Technology and Properties of Digital Double Pulse Electrodepositing Ni-HA Composite Coating of Bioceramics

This article discusses and analyses the technology, the surface image, microstructure and ability of digital double pulse electrodepositing Ni-HA composite coatings of bioceramics made on 1Crl8Ni9Ti substrate by SEM ,XRD and so on. The results shows that ( 1 ) the HA particles exit in substrate uniformly; (2) XRD result shows that there are HA peaks at 78. 023 ° ,43. 246°and 73. 120°differently; (3) The microhardnees of the composite coatings is increased with the rise of content of HA particles, and on the same conditions the microhardnees value is greater than that of common non-pulse electrodepositing Ni-HA composite coatings of bioceramics. (4) The grain size of digital double pulse electrodepositing Ni-HA composite coatings of bioceramics is much thinner than that of common D. C.     

Hydrothermal-electrochemical codeposited hydoxyapatite/yttria-stabilized zirconia composite coating

Hydroxyapatite(HA)/yttria-stabilized zirconia(YSZ) composite coatings were deposited on titanium substrates using a hydrothermal electrochemical method in an electrolyte containing calcium, phosphate ions and YSZ particles. HA/YSZ composite coatings were prepared in different conditions with different electrolyte temperatures(100 ∼ 200°C), current densities(0.1 ∼ 10.0 mA/cm²), and particles content in bath(0 ∼ 100 g/L). The effect of YSZ additions on the phase composition, microstructure, thermal stability, corrosion behavior and the bonding strength of HA/YSZ composite coatings were studied. The results show that crystallinity of HA in HA/YSZ composite coatings increase continuously with the electrolyte temperature and close to stoichiometric HA. The n(Ca)/n(P) ratio at 200°C is about 1.67 according with stoichiometric HA. YSZ particles are imbedded uniformly between the HA crystals. The average HA crystal size are reduced owing to the additions of YSZ particles. After annealing at 1200°C, tetragonal phase YSZ tend to react with the released CaO to form cubic phase YSZ and CaZrO₃, which cause destabilization of HA to decompose into more α-TCP phase. The bonding strength between HA/YSZ composite coatings and titanium substrates increase with increasing volume content of YSZ in the composite coatings (V %). HA/YSZ composite coatings exhibit a better electrochemical behavior than pure HA coatings and uncoated Ti metals.     

Ni-Al2O3复合镀工艺及镀层性能的研究

介绍了Ni-Al2O3耐磨复合镀的制备工艺,讨论了工艺参数对镀层质量的影响.研究表明,电流密度增大不利于提高镀层中纳米颗粒的含量,pH值增大会使复合含量降低,电镀时适当搅拌或适当改变搅拌方式可以使复合镀层中的纳米颗粒含量提高.Al2O3颗粒的加入能有效阻止镍晶粒的生长,且在颗粒附近复合镀层的硬度比镀纯镍成倍的提高,Al2O3颗粒越细小作用越明显.目的是提高不锈钢表面的耐磨性,制备的复合镀层耐磨性高于镀纯镍.确定了适宜的工艺范围:纳米粉体质量浓度为10～20 g/L,电镀时间10～15 min,电流密度1.5～2.0 A/dm2,pH值为4.0～5.0,机械搅拌速度120 r/min,超声波功率200 W,电镀温度45℃.     

WC-Co添加量对激光熔覆镍基涂层微观结构及摩擦学性能的影响

为了使激光熔覆镍基耐磨涂层得到更广泛的应用,通过激光熔覆技术在1Cr18Ni9Ti不锈钢表面制备了NiCrBSi/WC-Co镍基涂层,研究了WC-Co添加量对涂层微观结构及摩擦学性能的影响。结果表明:随WC-Co添加量的增加,镍基涂层的结构由枝晶和枝晶间的共晶逐渐向球状晶和块状晶转变,涂层的硬度和耐磨性增加。     

激光熔覆微-纳米碳化钨复合涂层结构与性能研究

以微米和纳米级晶粒Co包碳化钨为增强相,自熔合金粉末Ni60B为粘结剂,采用激光熔覆的方法在45钢表面制备出微-纳米碳化钨增强Ni基合金复合涂层.采用扫描电镜、X射线衍射等手段对粉末和涂层的相结构、显微组织等进行了分析观察,采用显微硬度计分析了涂层表面硬度随成分的变化规律和截面硬度的分布曲线.结果表明,纳米碳化钨粉末的添加有助于改善涂层的熔覆性能和提高涂层的表面硬度.     

纳米SiC浓度对Ni/纳米MoS_2基复合镀层结构和耐磨性能的影响

采用双脉冲复合电镀技术,在瓦特型镀液中,制备含纳米SiC的Ni/MoS2基复合镀层。研究纳米SiC浓度对复合镀层微观形貌、组织结构、显微硬度和摩擦性能的影响。结果表明:镀液中添加纳米SiC后,Ni/MoS2复合镀层的微观形貌产生明显的变化,随镀液中SiC浓度的增加,复合镀层表面致密度提高;镀液中纳米SiC浓度在1.0~1.5g/L时,组织由Ni+MoS2+SiC组成;纳米SiC为1.5g/L时,显微硬度达到最大,为505HV,摩擦因数为0.28,分别为纯Ni/MoS2的1.6倍和1/2。复合镀层的磨损机制以磨料磨损为主。     

Al particles size effect on the microstructure of the co-deposited Ni-Al composite coatings

Micrometer and nanometer Al particles were codeposited with nickel by electrodeposition from a nickel sulfate bath containng a similar content of Al particles. The effect of Al particles size on the microstructure of the electrodeposited Ni-Al composite coatings was analyzed. The results indicated that at a given Al particles content the incorporation of Al nanoparticles instead of the microscale countparts significantly increased the particle number per unit volume in the composite, led to a more homogeneous distribution of particles, and finer Ni grains due to nucleation of smaller Ni grains on the surface of Al nanoparticles, which changed the direction of the local Ni growth and caused the formation of a fine equiaxed grain structure.