中文摘要：

利用两相萃取法合成了二辛基胺二硫代氨基甲酸（DTC8）表面修饰铜纳米微粒;采用X射线衍射仪、透射电子显微镜、红外光谱仪表征了铜纳米颗粒的尺寸、形貌和结构,采用四球摩擦磨损试验机评价了纳米铜添加剂在液体石蜡中的摩擦学性能,并采用扫描电子显微镜观察了磨斑形貌。结果表明：DTC8修饰铜纳米微粒的粒径较小,粒径分布较窄。与此同时,表面修饰纳米铜作为润滑油添加剂具有优异的抗磨性能,这可能是由于熔点低且易变形的纳米铜可填充磨损表面微坑而起到自修复作用所致。

英文摘要：

Cu nanoparticles surface-modified by dioctylamine dithiocarbamate （DTC8） were synthesized using a two-phase extraction route. The size, morphology and structure of resultant surface-capped Cu nanoparticles （coded as DTC8-Cu） were analyzed by means of X-ray diffraction, transmission electron microscopy and infrared spectrometry. The tribological behavior of DTC8-Cu as an additive in liquid paraffin was evaluated with a four-ball machine, and the surface topography of the wear scar was also examined by means of scanning electron microscopy. Results show that Cu nanoparticles modified by DTC8 have a small particle size and a narrow size distribution. Besides, DTC8-Cu as an additive in liquid paraffin has excellent antiwear ability, due to the deposition of nano-Cu with low melting point on worn steel surface leading to the formation of a self-repairing protective layer thereon.