MEASUREMENT OF ADHESION FORCES IN AIR WITH THE VIBRATION METHOD

作     者：Siegfried Ripperger Konrad Hein 

作者机构：Lehrstuhl für Mechanische Verfahrenstechnik Technische Universit(a|¨)t Kaiserslautern67653 Kaiserslautern Germany Lehrstuhl für Mechanische Verfahrenstechnik Technische Universit(a|¨)t Dresden 01062 Dresden Germany 

出 版 物：《China Particuology》 (CHINESE PARTICUOLOGY)

年 卷 期：2005年第3卷第1期

页      面：3-9页

核心收录：

学科分类：081704[工学-应用化学] 08[工学] 0817[工学-化学工程与技术] 081701[工学-化学工程] 

基　　金：the Research Programme(Ri 776/9-3) 

主　　题：adhesion force vibration method roughness 

摘      要：The vibration method represents a practical method for the measurement of adhesion forces and adhesion force distributions. This method causes sinusoidally alternating stresses and yields detachment and contact forces between particles and substrate of the same order of magnitude. Alternating contact forces of the vibration method can cause an adhesion force intensification through flattening of asperities. The measuring principle of the vibration method and the analysis of experimental results are described in the article. Normal adhesion forces (pull-off forces) are measured using the vibration method and the colloidal probe technique. The results of both methods show good agreement for small particle sizes. The influence of the detachment force direction is shown by comparing tangential and normal adhesion forces measured using particle reentrainment in a turbulent air flow and the vibration method, respectively. The surface roughness of the substrate and the relative humidity are shown to significantly influence the measured adhesion forces. For the calculation of the adhesion forces, an approach by Rabinovich was combined with approximations of plastic micro asperity flattening. The Rabinovich approach accounts for roughness effects on the van der Waals force by incorporating the rms roughness of the interacting surfaces, rms-values of the particles and substrates were measured with atomic force microscopy at different scanning areas.