Frictional Characteristics of Sub-100-μm Borosilicate Glass Balls for Actuator Applications

Jae Kang Kim, Shin Sung Yoo, Narguess Nemati, Dae Eun Kim

Research output: Contribution to journalArticlepeer-review

4 Citations (Scopus)


The frictional characteristics of ∼62-μm diameter borosilicate glass balls used as rolling elements for a miniature electromagnetic linear actuator were assessed. The glass balls were placed between two silicon plates of the actuator with linear bearing tracks fabricated in the shape of V-grooves on the silicon surface. Rolling friction experiments were conducted using the electromagnetic linear actuator as well as a tribotester. It was shown that the glass balls were effective in generating a low friction coefficient of ∼0.01 over 11 million cycles under a load of 6.6 mN. For the durability test using the tribotester, a relatively high load of 245 mN was applied. In this case, evidence of silicon surface damage could be found. The feasibility of using Au as a solid lubricating film on the silicon surface was investigated. It was found that the friction coefficient and surface damage depended on the thickness of the film, which was varied from 7∼20 nm. It was postulated that the low shear strength of Au aided in reducing the friction coefficient from ∼0.017 to ∼0.013. With improved adhesion of the Au coating on silicon, the use of sub-100-μm borosilicate glass balls as rolling elements for miniature actuators seems promising.

Original languageEnglish
Article number7283545
Pages (from-to)2161-2169
Number of pages9
JournalJournal of Microelectromechanical Systems
Issue number6
Publication statusPublished - 2015 Dec 1

Bibliographical note

Publisher Copyright:
© 1992-2012 IEEE.

All Science Journal Classification (ASJC) codes

  • Mechanical Engineering
  • Electrical and Electronic Engineering


Dive into the research topics of 'Frictional Characteristics of Sub-100-μm Borosilicate Glass Balls for Actuator Applications'. Together they form a unique fingerprint.

Cite this