Contact between submicrometer silica spheres.
Recently, the scope of the investigation of the deformation mechanism extended to the micrometer and submicrometer regimes. The sphere-substrate contact method was usually used because it is rather difficult to make two micrometer or submicrometer spheres contact each other precisely. Here, we used the sphere-sphere contact method via a novel, simple process to investigate the deformation of spheres. The silica particle size ranges from 400 to 900 nm. Traditionally, the harder the particle, the smaller both the contact radius and the adhesion force. Therefore, it is widely accepted that silica particles should undergo elastic deformation, but we found that silica particles underwent plastic deformation rather than elastic deformation because of van der Waals interaction. The contact radii were observed by scanning electron microscopy (SEM).
Wang
Xiao-Dong
XD
Institute of Precision Optical Engineering, Department of Physics, Tongji University, Shanghai 200092, China.
Shen
Zheng-Xiang
ZX
Zhang
Jin-Long
JL
Jiao
Hong-Fei
HF
Cheng
Xin-Bin
XB
Ye
Xiao-Wen
XW
Chen
Ling-Yan
LY
Wang
Zhan-Shan
ZS
D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D054118:Nanospheres / Q000737:chemistry / Q000648:ultrastructure; D012822:Silicon Dioxide / Q000737:chemistry*
D012822:Silicon Dioxide