两种化学复合镀层的耐磨性能之比较

本文用化学复合镀技术,在４５钢基体上沉积了镍－磷－巴基管和镍－磷－碳化硅两种复合镀层。作者详细实验研究了此两种复合镀层的摩擦,磨损工进行了比较。结果表明,两种复合镀层均具有优异的耐磨特性。并且镍－磷－巴基管复合镀层的耐磨特性更佳。     

巴基管的润滑性能研究

本文实验研究了镍－磷－巴基管复合镀层的润滑性能，结果表明：巴基管复合镀层具有优良的减摩，耐磨特性，说明巴基管是一种性能优异的固体润滑材料。     

镍-磷-三氧化二铝化学沉积非晶态复合镀层的显微组织和耐磨性的研究

为了进一步发挥化学沉积单一非晶态镀层的性能潜力,研究了化学沉积镍磷合金镀液中添加三氧化二铝微粒以获得镍-磷-三氧化二铝复合层的新工艺。对化学沉积复合镀层的显微组织结构、显微硬度、时效处理时的晶化与过饱和相的析出以及复合镀层的耐磨往进行了测试。结果表明,与单一非晶态镀层相比,复合镀层的显微硬度和耐磨性能均更为优异,是一种工艺成本低廉、操作控制简便的表面强化新途径。     

Al2O3增强镍-磷-钨复合镀层的制备及性能

为了提高镍-磷-钨合金镀层性能,制备了Al2O3增强的镍-磷-钨复合镀层;探讨了镀液中Al2O3颗粒尺寸、搅拌方式、电流密度、镀液中Al2O3、Na2WO4的含量和pH值等对镀速、镀层中Al2O3的质量分数及镀层外观质量的影响;确定了复合电沉积最佳工艺条件;并对镀层的硬度、耐磨性能、抗高温氧化性能、耐腐蚀性能、表面形貌、相结构和化学成分等进行了测试.结果表明:在超声波振荡搅拌下,加入纳米Al2O3,控制电流密度为2A·cm-2,镀液中Al2O3和Na2WO4的含量分别为50g·L-1和6g·L-1,pH值为5.0时,镀速和镀层中的Al2O3质量分数最大,镀层质量最佳;加入微米和纳米Al2O3镀层的综合性能均高于未加入Al2O3的镀层.     

金属陶瓷复合镀层的组织与滑动磨损性能研究

在镍磷合金基质镀层中,添加ＳｉＣ、Ａｌ２Ｏ３粒子,可形成金属陶瓷复合镀层。研究结果表明,这种复合镀层的组织与滑动磨损性能随着ＳｉＣ、Ａｌ２Ｏ３粒子的复合量增加其组织结构发生变化;复合镀层比镍磷镀层具有更高的耐磨性能,４００℃×１ｈ时效处理后,磨损性能最佳,且Ｎｉ（Ｐ）－ＳｉＣ复合镀层优于Ｎｉ（Ｐ）－Ａｌ２Ｏ３。     

Ni-P/SiC、Ni-P/WC纳米复合电刷镀镀层的组织与性能

利用电刷镀技术制备了Ni-P/SiC、Ni-P/WC纳米复合镀层;用扫描电镜、X射线衍射仪和电子探针等分析了复合刷镀层表面形貌、微观组织结构、成分分布,并进行了硬度和耐磨性试验.结果表明:与传统镍磷镀层相比较,纳米颗粒的加入使复合镀层中的组织结构更加致密,显微硬度有较大程度的提高,耐磨性增强,其中Ni-P/WC镀层的性能优于Ni-P/SiC镀层.     

镁合金表面化学镀镍-磷合金稳定剂的选用

研究了KI、KIO3、PbAc2、KIO3+PbAc2和KIO3+硫脲五种稳定剂对镁合金表面化学镀镍-磷合金镀液的稳定性、镀层的表面形貌及性能的影响,并优选出适合于镁合金表面化学镀镍、磷合金镀层的最佳稳定剂。结果表明:随着稳定剂的加入,镀液的稳定性得到了改善,但不同种类稳定剂对镀液的稳定效果不同;二元复合稳定剂所得镀层的表面形貌、质量优于单一稳定剂的;根据镀层的性能,确定出KIO3+硫脲稳定剂是本试验条件下的最佳稳定剂。     

添加纳米MoS2镍-磷化学复合镀层的制备与微观形貌

运用化学复合镀技术制备出添加纳米MoS2的镍-磷复合镀层.研究了制备过程中镀液中分散剂种类、MoS2添加数量以及镀前试样表面粗糙度对复合镀层的影响.结果表明:十六烷基三甲基溴化铵(CTAB)可以很好地在镀液中分散纳米MoS2,镀液中添加纳米MoS2颗粒的最佳值是2.0 g/L;镀前试样表面粗糙度值过低不利于提高复合镀层中纳米MoS2的复合量.     

镍-磷-纳米Al2O3复合镀层的摩擦学性能

用化学镀的方法制备了镍-磷-纳米Al2O3复合镀层，研究了热处理温度对镀层硬度和磨损性能的影响，并与二元镍-磷镀层以及镍-磷-Al2O3复合镀层进行了性能对比。结果表明：含有纳米Al2O3微粒的复合镀层具有更高的硬度和耐磨性，经400℃处理后的镀层耐磨性最好。     

镍、硼、碳纳米管复合镀层的性能研究

用化学复合镀的方法,把碳纳米管作为第二相加入到化学镀镍、硼镀液中得到复合镀层;改变还原剂二甲胺硼烷在镀液中的相对浓度,得到各种镀层表面成分;利用摩擦磨损实验机、电化学综合测试仪、X射线光电子能谱（XPS）和扫描电子显微镜等分析复合镀层的摩擦磨损性能、耐腐蚀性能、表面形貌特性。结果表明：通过化学复合镀的方法得到镍、硼和碳纳米管复合镀层,其平均厚度为7~8μm;随着二甲胺硼烷在镀液中的相对浓度增加,镀层的摩擦因数减小,磨损量和腐蚀电流也减小,说明随着二甲胺硼烷在镀液中浓度的增加,其耐磨性和抗腐蚀性逐渐提高;复合镀层中主要含有N i,C,O 3种元素,其中N i以单质的形态出现,B以N i2B化合物的形态出现,元素C以碳纳米管形式沉积在镍硼基体中。     

Effect of carbon nanotube addition on the tribological behavior of carbon/carbon composites

Carbon nanotube composite coatings were applied onto carbon/carbon composites to improve wear properties. Carbon nanotubes have been prepared by catalytic pyrolysis of hydrocarbons. The nanotube slurry was prepared by addition of phenolic resin and solvent to infiltrate into C/C composites. The nanotube added composites were then carbonized in a nitrogen atmosphere. Ball-on-disc type wear tests were performed to evaluate the tribological properties of the carbon nanotube added carbon composites. The result showed that addition of nanotube has the potential to increase the wear resistance of carbon composites. Changes in Raman spectra, morphology and surface damage were studied to explain observed wear behavior.     

电刷镀镍/碳纳米管复合纳米镀层的结构与磨损性能

用含碳纳米管的快速镍电刷镀液制备了镍/碳纳米管复合纳米镀层,研究了热处理温度和镀液中碳纳米管含量对镀层平均晶粒尺寸、结构、力学性能及耐磨性能的影响。结果表明,镀层的晶粒大小随热处理温度的升高是先降低而后增大的;同样碳纳米管的加入对镍刷镀层的平均晶粒尺寸和微结构有显著的影响。镀层的硬度和耐磨性与镀层的平均晶粒尺寸有非常好的对应关系。热处理和碳纳米管的强化作用可导致镀层晶粒细化和结构致密化,从而有效地改善了镀层的力学性能和耐磨性能。     

Effects of carbon fillers on the tribological and mechanical properties of an epoxy-based polymer (SU-8)

SU-8, an epoxy-based negative photoresist polymer, is highly suitable for making micro-electro-mechanical systems (MEMS) structures. Despite fabrication advantages, its bulk mechanical and tribological properties are the main limitations for application as MEMS material. Carbon filler materials such as graphene, graphite and multi-walled carbon nanotube (MWCNT) are added to SU-8 for tribological and mechanical property enhancements. SU-8/(5 wt%) graphite composite has performed better for the steady-state coefficient of friction at all loads including for the speed effect. SU-8/(5 wt%) MWCNT has shown excellent wear resistance. At 10 wt% graphite content, SU-8/graphite is superior in tribological performance to other composites tested.     

碳纳米管增强铜基复合材料的研究进展

综述了碳纳米管增强铜基复合材料的预处理和制备方法,探讨了复合材料的组织、力学性能与摩擦学性能、电学性能和热学性能;最后指出了碳纳米管增强铜基复合材料今后的研究方向。     

Effect of Carbon Nanotube Addition on Tribological Behavior of UHMWPE

Carbon nanotubes (CNTs) were added to Ultra-high molecular weight polyethylene (UHMWPE) to improve the tribological properties of UHMWPE. CNTs which have a diameter of about 10–50 nm, while their length is about 3–5 nm were produced by the catalytic decomposition of acetylene gas using a tube furnace. Ball-on-disc-type wear tests were performed to evaluate the tribological performance of UHMWPE composites reinforced with CNTs. The results showed that addition of carbon nanotube up to 0.5 wt% lowered wear loss significantly and increased friction coefficient slightly. Also through the scanning electron microscope (SEM), the surfaces of UHMWPE were observed and analyzed to discuss the tribological behavior of CNT added UHMWPE.     

Tribological characteristics of composite materials based on copper-carbon Nanotube powder system

Results are presented of studies on the influence of the carbon nanotube concentration on the tribological behavior of composite powder materials based on copper matrix obtained by electrocontact sintering. The tribological characteristics of materials based on the powder copper-carbon nanotube and copper-graphite systems are compared.     

Tribological Behavior of Carbon-Nanotube-Filled PTFE Composites

Carbon nanotube/polytetrafluoroethylene (CNT/PTFE) composites with different volume fractions were prepared and their friction and wear properties were investigated using a ring-on-block under dry conditions. It was found that CNTs signifi-cantly increased the wear resistance of PTFE composites and decreased their coefficient of friction. PTFE composites with 15–20 vol.% CNTs exhibited very high wear resistance. The significant improvements in the tribological properties of CNT/PTFE composites are attributed to the super-strong mechanical properties and the very high aspect ratio of CNTs. The CNTs greatly reinforce the structure of the PTFE-based composites and thereby greatly reduce the adhesive and plough wear of CNT/PTFE composites. The CNTs are released from the composite during sliding and transferred to the interface of the friction couples. They thus serve as spacers, preventing direct contact between the mating surfaces and thereby reducing both wear rate and friction coefficient.     

Influence of the multi-walled carbon nanotube and short carbon fibre composition on tribological properties of epoxy composites

The present research work deals with the development of a novel polymer composite for brake pad applications. The composite that was used consists of epoxy resin, carbon fibre and carbon nanotubes in varying weight percentage. The tribological performance of three different samples was tested using a pin-on-disc under dry contact condition. The results indicated that the sample filled with short carbon fibres (SCF), and multi-walled carbon nanotube (MWCNT) had superior performance. Reduction in wear rate was observed due to synergism between SCF and MWCNT as compared to SCF only. Scanning electron microscopy was subsequently performed on all samples. The micrographs show changes in the structural formation after the incorporation of SCFs and MWCNT. This increased composite structural strength and explains why SCF and MWCNT’s hybrid-filled composite material has better tribological properties.