Effect of surface roughness on the angular acceleration for a droplet on a super-hydrophobic surface  

作　　者：Longyang LI Jingfang ZHU Zhixiang ZENG Eryong LIU Qunji XUE 

机构地区：[1]Key Laboratory of Marine Materials and Related Technologies,Zhejiang Key Laboratory of Marine Materials and Protective Technologies,Ningbo Institute of Materials Technology and Engineering,Chinese Academy of Sciences,Ningbo 315201,China [2]SEU-FEI Nano-Pico Center,Key Laboratory of MEMS of Ministry of Education,Southeast University,Nanjing 210096,China [3]School of Materials Science and Engineering,Xi'an University of Science and Technology,Xi'an 710054,China

出　　处：《Friction》2021年第5期1012-1024,共13页摩擦（英文版）

基　　金：The authors acknowledge the financial support from the National Natural Science Foundation of China(Grant Nos.U1809214 and U1809213);the National Basic Research Program of China(973 Program)(Grant No.2013CB632302);the Foundation of Key Laboratory of Marine Materials and Related Technologies,Chinese Academy of Sciences(2018K01);the Foundation of Key Laboratory of Marine Materials and Related Technologies,CAS(2018K01).

摘　　要：The motion of droplets on a super‐hydrophobic surface,whether by sliding or rolling,is a hot research topic.It affects the performance of super‐hydrophobic materials in many industrial applications.In this study,a super‐hydrophobic surface with a varied roughness is prepared by chemical‐etching.The adhesive force of the advancing and receding contact angles for a droplet on a super‐hydrophobic surface is characterized.The adhesive force increases with a decreased contact angle,and the minimum value is 0.0169 mN when the contact angle is 151.47°.At the same time,the motion of a droplet on the superhydrophobic surface is investigated by using a high‐speed camera and fluid software.The results show that the droplet rolls instead of sliding and the angular acceleration increases with an increased contact angle.The maximum value of the angular acceleration is 1,203.19 rad/s^(2) and this occurs when the contact angle is 151.47°.The relationship between the etching time,roughness,angular acceleration,and the adhesion force of the forward and backward contact angle are discussed.

关 键 词：super‐hydrophobic surface adhesive force rolling friction contact angle 

分 类 号：TB306[一般工业技术—材料科学与工程]