Experimental Study on Ultra-Structure and Frictional Properties of Zaocys Dhumnades’s Ventral Scale

Abstract:

The ultra-structures of Zaocys dhumnades’s ventral scale surface were observed by the AFM (Atomic Force Microscopy), at the same time, the frictional properties between ventral scale and the stainless steel ball under different load, different velocity and different lubrication condition were investigated by mode UMT-2 of Universal Micro Materials Tester. The results show that ultra-structure of Zaocys dhumnades’s ventral scale surface is comprised of periodically arrayed micro-fibers and micro-pits, there are micro-pits at its bottom. The frictional resistance on the ventral scale surface is low under the dry friction, whose average frictional coefficient is 0.064, and the friction coefficient increases under the water or oil lubrication, while it decrease with load and velocity increase under different conditions. The reasons of the low friction resistance of ventral scale are its surface ultra-structure, hydrophobic and lower shearing strength. The investigative results provide theoretical proof of reducing adhesion and resistance for frictional surface of bionics fabrication.

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