烧结型NdFeB永磁体表面有机纳米复合膜的制备及性能

Preparation and Properties of Polymeric Nano Composite Film on Surface of Sintered NdFeB Permanent Magnet

采用自组装分子膜技术在烧结型NdFeB永磁体表面制备了三嗪硫醇三乙基硅烷(TES)自组装分子膜(TES-SAMs),在TES-SAMs的基础上利用自主开发的有机镀膜技术制备了具有含氟官能团的三嗪硫醇(ATP)有机纳米复合薄膜(TES-ATP).通过X射线光电子能谱仪(XPS)、傅里叶变换红外(FTIR)光谱仪、椭圆偏振光谱仪、原子力显微镜(AFM)和接触角测量仪对薄膜的表面状况进行评价,使用UMT-2型摩擦磨损试验机研究TES-SAMs和TES-ATP的微摩擦学性能.研究结果表明:TES-SAMs和TES-ATP的膜厚分别是5.08和29.78nm;表面自由能从基体的73.13mJ·m-2下降到TES-SAMs的63.69mJ·m-2和TES-ATP复合膜的10.19mJ·m-2,且TES-ATP复合膜对蒸馏水的接触角为123.5°,成功实现了NdFeB表面由亲水到疏水的转换.TES-SAMs和TES-ATP均能有效降低摩擦系数,TES-SAMs的摩擦系数为0.22,TES-ATP的摩擦系数为0.12,而基体的摩擦系数为0.71;同时,TES-ATP还表现出良好的抗磨性能.TES-ATP复合膜为微机电系统中的摩擦磨损问题的解决提供了一种新思路.

A nanofilm（TES-SAMs） was prepared by self-assembly of 6-（3-triethoxysilylpropylamino）-1,3,5-triazine-2,4-dithiol monosodium（TES） on a sintered NdFeB surface.A nano composite film（TES-ATP） was then prepared on the TES-SAMs surface by a self-developed polymer plating technique using 6-（N-allyl-1,1,2,2-tetrahydroperfluorodecylamino）-1,3,5-triazine-2,4-dithiol monosodium（ATP）.The surface of the TES-SAMs and TES-ATP were characterized by X-ray photoelectron spectroscopy（XPS）,Fourier transform infrared（FTIR） spectroscopy,spectroscopic ellipsometry,atomic force microscopy（AFM）,and contact angle measurements.A UMT-2 tribometer was used to investigate their micro-tribological properties.The experimental results showed that the thicknesses of TES-SAMs and TES-ATP were 5.08 and 29.78 nm,respectively.The surface free energy of TES-ATP and TES-SAMs decreased from 73.13 mJ·m-2 for the substrate to 10.19 and 63.39 mJ·m-2,respectively.The contact angle of distilled water on TES-ATP was 123.5°,indicating transformation from a hydrophilic surface to a hydrophobic one.The friction coefficient was effectively reduced from 0.71 for the substrate to 0.22 for TES-SAMs and 0.12 for TES-ATP.In addition,the TES-ATP composite film possessed excellent anti-wear ability.Thus,the present TES-ATP composite film provides a novel approach to solving tribological issues in micro-electro-mechaanical system（MEMS）.