齿条表面化学镀Ni-P-SiC镀层耐磨性的研究

对齿条表面化学镀Ni-P-SiC镀层的耐磨性进行了研究.结果表明:Ni-P-SiC镀层具有弥散强化、沉淀强化和固溶强化三重强化机制,齿条表面Ni-P-SiC镀层可以大幅度提高齿条的耐磨性,并有利于纤维梳理.     

复合化学镀Ni-P-SiC工艺研究

通过正交试验对复合化学镀Ni-P-SiC工艺参数进行了优化,并确定了镀液的最佳温度、搅拌速度、酸碱度及SiC微粉的加入量,最后对镀层性能进行了测试.     

化学复合镀Ni—P—SiC的研究

研究了在Ni—P化学镀液中添加分散剂A及SiC微粒得到的化学镀Ni—P—SiC复合镀层。并研究了Ni—P—SiC化学共沉积工艺及其镀层性能。其结果表明,该复合镀层附着性好,     

Ni—P—Al2O3化学镀工艺研究

通过正交实验对施镀工艺参数进行了优化,并确定了镀层的合理化热处理温度,研究了镀液成分及工艺参数对镀层厚度,镀层耐磨性及镀层中Al2O3颗粒分布的影响。实验结果表明,Ni-P-Al2O3复合化学镀层硬度可达HV0.11400左右,耐磨性比化学镀Ni-P大大提高。     

七学复合镀Ni—P—（RE）—SiO2的工艺及性能研究

本文研究了化学镀Ni—P—(RE)—SiO2复合镀层工艺中SiO2含量、稀土含量、表面活性剂种类及含量和搅拌方式等因素对镀层中SiO2含量及镀速的影响；并对镀层的表面形貌和性能进行了测定。结果表明：该复合镀层附着性好，有较强的耐蚀性能。     

化学镀Ni—P复合耐磨镀层的研究进展

化学镀Ni—P镀层具有良好的耐蚀性,但耐磨性不佳,通过引入纳米或微米粒子可以提高其耐磨性。本文综述了近几年来国内外在颗粒增强复合镀层、稀土增强复合镀层和减摩复合镀层方面的研究进展,并指出了Ni—P复合耐磨镀层在基础研究中的主要发展方向。     

Ni-P/纳米TiO2复合镀层的制备与性能

采用电泳沉积-化学镀两步法制备了化学镀Ni-P/纳米TiO2复合镀层,研究了电场强度、电流及电泳时间对电泳工艺的影响,确定了合适的化学镀工艺参数,用X射线衍射和扫描电镜对复合镀层的结构进行分析,测试了复合镀层的显微硬度,用甲基橙为模型反应物对复合镀层进行光催化降解实验.实验结果表明,纳米TiO2颗粒在复合镀层中分布均匀,在镀态下和经过热处理后复合镀层显微硬度均高于化学镀镍磷合金,复合镀层催化效果与纳米二氧化钛涂层相当.     

镍—磷—聚四氟乙烯复合材料化学镀研究（一）

本文介绍了镍－磷－聚四氟乙烯复合材料化学镀层的条件,化学镀复合材料的镀液要求和特性,影响复合镀的主要因素,化学镀镍－磷－聚四氟乙烯复合镀层工艺。     

复合化学镀Ni—P—SiC工艺研究

通过正交试验对复合化学镀Ni—P—SiC工艺参数进行了优化，并确定了镀液的最佳温度、搅拌速度、酸碱度及SiC微粉的加入量，最后对镀层性能进行了测试。     

SiC在Ni-P-SiC化学复合镀层中共析因素研究

在实现Ni-P-SiC化学复合镀时，影响分散剂SiC在镀层中共析的因素很多，作者选择其中几个基本因素如分散剂的添加量、分散剂粒子的大小，镀液的搅拌速度、试验片的定位角度、镀层析出速度等进行了研究，在充分的实验基础上，明确了这些因素对镀层中SiC共析量的影响并探讨了其原理。     

Ni/纳米Al2O3微粒复合电镀工艺的试验研究

采用复合电镀的方法在45#钢表面制备获得Ni/纳米Al2O3微粒复合镀层.利用正交试验法研究了电流密度、镀液pH值和镀液温度对Ni/纳米Al2O3微粒复合镀层性能和沉积过程的影响.结果发现,它们对镀层沉积过程及其性能都有影响,但影响的程度和规律不同.最后综合考虑各因素,制订出Ni和纳米Al2O3微粒在45#钢表面发生共沉积的较理想工艺.     

Ni-SiO2复合镀层组织和性能的研究

应用电刷镀技术在45钢表面制备含有微米SiO2的镍基复合镀层,研究了复合镀层表面形貌,测试了镀层的显微硬度和摩擦磨损性能,分析了微米陶瓷颗粒沉积量对镀层摩擦磨损性能的影响.实验结果表明,微米陶瓷颗粒复合镀层较快速镍镀层具有更高的显微硬度和良好的耐磨性.     

Dry wear behaviors of wear resistant composite coatings produced by laser cladding

Using different proportional mixtures of Ni-coated MoS2, TiC and pure Ni powders, new typical wear resistant and selflubricant coatings were formed on low carbon steel by laser cladding process. The microstructures and phase composition of the composite coatings were studied by SEM and XRD. The typical microstructure of the composite coating is composed of multisulfide phases including binary element sulfide and ternary element sulfide, γ-Ni, TiC and Mo2C. Wear tests were carried out using an FALEX-6 type pin-on-disc machine. The friction coefficient and mass loss of three kinds of MoS2/TiC/Ni laser clad coatings are lower than those of quenched 45 steel, and the worn surfaces of the laser cladding coatings are very smooth. Because of high hardness combined with low friction, the laser cladding composite coating with a mixture of 70% Ni-coated MoS2, 20%TiC and 10% pure Ni powder presents better wear behaviors than the composite coating with other powder blends. The composition analysis of the worn surface of GCr15 bearing steel shows that the transferred film from the laser cladding coating to the opposite surface of GCr15 bearing steel contains an amount of sulfide, which can change the micro-friction mechanism and lead to a reduced friction coefficient.     

Microstructure and tribological properties of laser clad Ni-Ag/Tic composite coating

Ni-Ag/TiC composite coating was prepared on the 45 steel substrates by means of laser cladding. Microstructure and wear properties of composite coatings were analyzed using optical microscopy, field emission scanning electron microscopy and wear machine. The experimental results show that defects, such as cracks and pores, do not occur in the laser-cladded Ni-Ag/TiC composite coating and 45 steel substrate, and they present good metallurgical bonding between them. Compared with Ni/TiC composite coating, micro- hardness values of the two coatings do not present evident differences. The wear experiment result shows that Ni-Ag/TiC composite coated with Ag possesses low friction coefficient and good wear resistance compared with Ni/TiC composite coating.     

镍/聚苯胺复合材料的制备及其性质

采用原位聚合法制备不同质量比的镍粉(Ni)、聚苯胺(PANI)复合材料,其中以柠檬酸为掺杂酸,过硫酸铵作氧化剂。通过X射线衍射(XRD)和傅里叶红外线光谱仪(FTIR)对该复合材料的结构进行表征与分析。结果表明复合物中Ni与PANI之间不存在化学键的作用。将制备的Ni/PANI复合材料和镍粉作为填料制成涂料,涂层用四探针测试仪和网络分析仪进行表征和分析,研究不同质量比的填料对涂层性能的影响。结果表明:在填料质量比相同的涂层中,原位制备复合材料涂层的电导率和屏蔽效能均高于机械混合制备的复合材料;当原位制备的复合材料中Ni,苯胺(AN)质量比为1:4时,涂层的电导率和屏蔽效能均高于其他涂层,电导率达92.575 S/cm,屏蔽效能在所测频率范围内在70 dB以上,其中60%左右为吸收损耗。     

等离子喷涂NiCr/Cr_2C_3、Ni/C及其复合涂层的耐磨性能

为了加强车辆机械零件的表面防护,采用等离子喷涂工艺在304N不锈钢表面分别制备了NiCr/Cr_2C_3涂层、Ni/C涂层以及NiCr/Cr_2C_3和Ni/C复合涂层,观察了涂层组织形貌,测试了涂层硬度和耐磨性,分析了涂层的摩擦磨损机理.结果表明,3种涂层中NiCr/Cr_2C_3和Ni/C复合涂层的耐磨性能最好.金属粘结相NiCr可以起到足够的支撑作用,从而防止涂层剥离与黏着磨损的产生.Ni/C作为固体润滑剂,通过自润滑作用降低了涂层的整体摩擦系数.     

Sand-wear resistance of brush electroplated nanocomposite coating in oil and its application to remanufacturing

Sand-wear resistance of nano scale alumina particle reinforced nickel matrix composite coating (n-Al₂O₃/Ni) prepared by brush electroplating technique was investigated via wear tests in sand-contaminated oil lubricant, comparing with that of AISI1045 steel and brush electroplated Ni coating. Effects of testing load, sand content and sand size on worn volume of the three materials, and also coating surface roughness on worn volume of the brush electroplated coatings were accessed. Results show that the worn volume of all the three materials increases with increasing of testing load, sand content and sand size. In the same conditions, n-Al₂O₃/Ni composite coating has the smallest worn volume while AISI1045 steel has the largest because of the n-Al₂O₃ particle effects. As to n-Al₂O₃/Ni and Ni coatings, the surface-polished coatings have obviously lower worn volume than the as-plated coatings. The brush electroplated n-Al₂O₃/Ni composite coating was employed to remanufacture the sand-worn bearing seats of a heavy vehicle and good results were gained. Foundation item: Project (50235030) supported by the National Natural Science Foundation of China; Project (51489020104ZD0401) supported by the National Key Laboratory for Remanufacturing; Project(51418060105JB3058) supported by National Defence Foundation     

Abrasive wear behaviors of high velocity arc sprayed iron aluminum composite coatings

The High Velocity Arc Spraying （HVAS） technology was used to prepare Fe-Al composite coatings by the adding of different elements into cored wires to obtain different Fe-Al coatings. The added compounds do great effect on the properties of the composite coatings. The microstructures and abrasive wear performances of the coatings were assessed by transmission electron microscopy （TEM）, scanning electron microscopy （SEM）, and THT07-135 high temperature wear equipment. It was found that the adding of Cr3C2 can greatly increase the room temperature wear behavior, and Fe-Al/WC coatings have adapting periods at the beginning of wear experiment. With the rise of temperature, the wear resistance of Fe-AI/Cr3C2 coatings becomes bad from room temperature to 250℃, and then stable from 250℃ to 550℃; the wear resistance of Fe-Al/WC becomes well with the rise of temperature. The adding of Cr and Ni can also improve wear performances of Fe-Al composite coatings.     

Morphology and tribological properties of Ni/n-SiO_2 composite coatings by pulse-reverse current brush-plating

1INTRODUCTION Pulse reversecurrent(RC)platingisanew technologycomingwithpulsecurrent(PC)andre versecurrent.Onthisaspect,earlierstudiesmani festedthat[16],intheconditionofRC,theeffectofelectricdoublelayerwasrestrained,thecontrol ofcrystallinegrowthwasenfor…     

等离子弧喷焊Mo/Ni60合金复合涂层的研究

采用等离子弧喷焊法制备了Mo/Ni60复合涂层.测定了喷焊层的耐磨性,并用光学显微镜对覆层进行了金相组织观察,利用X射线衍射分析了覆层的相结构.结果表明:加入Mo的镍基等离子喷焊层组织得到均匀化,共晶体细化,耐滑动磨损性能得到改善.