English Abstract

Analysis of Contact States Between Rubber and Mated Surface Using X-ray Imaging Method
-Real Time Observations of Rubber Breakage during Friction-

Masaki SATO
Yokohama Rubber Co., Ltd., Hiratsuka, Kanagawa, Japan
Nippon Gomu Kyokaishi,(2014),87(7),278-283 Original Paper in Japanese

Breakage of rubber rubbed against abrasive cloth was observed by a real time X-ray imaging method to clarify mechanisms of wear initiation.
The synchrotron radiation experiments were performed at the BL20XU in the SPring-8 with the approval of the Japan Synchrotron Radiation Research Institute (JASRI) (Proposal No. 2006B0109). X-ray energy was 15 keV. C4742-98-24A camera was used. Silica- or carbon black- filled SBRs were rubbed against #24 zirconium cloth. A crack at the rubber surface was observed when the rubber was rubbed against a sharp grain. The crack was generated perpendicular to the rubber surface at the middle between the bottom line of the rubber specimen and the top of the sharp grain. No cracks were observed when the rubber was rubbed against blunt grains in this experiment. The frictional force was maximized when the crack was generated.
It is thought that the crack of the rubber surface during friction was generated by an excess of rubber strain when the rubber hanged on the sharp grain.

Keywords: Friction, Wear, Rubber, Contact, Tribology, X-ray Imaging, Crack Generation