MWCNTs复合物纳米流体的摩擦学性能

将油性剂油酸(OA)填充进多壁碳纳米管(MWCNTs)的空腔内制备复合物,再以复合物为添加剂制备一种纳米流体,考察了复合物的质量分数、MWCNTs的酸处理时间以及摩擦测试条件等对纳米流体摩擦学性能的影响,并分析了复合物的润滑机理.结果表明:油酸被成功填充到经酸处理的MWCNTs管内,填充率约20%;摩擦过程中,复合物制备的纳米流体的摩擦系数有不断减小趋势,其减摩效果甚至优于同等含量的油酸乳化液;当复合物的质量分数为0.1%左右时,纳米流体可获得最佳的减摩、抗磨效果;随着酸化处理时间的增加,复合物制备的纳米流体的减摩、抗磨性能会有所提高.摩擦过程中,复合物可释放出油酸并形成润滑膜,MWCNTs则能够在油酸形成的润滑膜上发挥"微轴承"的作用,从而使复合物获得更加优良的减摩、抗磨效果.

Tribological Properties of Nanofluid Prepared by Composite of Multi-walled Carbon Nanotube and Oleic Acid

Multi-walled carbon nanotubes (MWCNTs) were filled with oleic acid (OA) to prepare the composite additives for use in the nanofluid. The influence of additive concentration, acid treatment time of MWCNTs, the test conditions on the tribological properties of the nanofluid were investigated, and the lubrication mechanism of the composite was also studied. The results showed that the OA was successfully filled into the MWCNTs with a filling rate of about 20%. In the process of friction, the friction coefficient of nanofluid prepared by the composite tended to decrease gradually, and its final friction reduction effect was even better than that of the oleic acid emulsion under different loads. The nanofluid could achieve better tribological properties as the concentration of the composite was about 0.1%. The tribological properties of the nanofluid would be improved with the increase of the acidification time. It was supposed that the composite could release the OA to form a lubrication layer during the friction process, which enabling the MWCNTs to play a role of "micro-bearing" on the formed lubrication film, thus the better tribological properties of the composite were achieved.