Study On Molding Process And Friction Behavior Of PDMS Surface Induced By The Electric Field

Surface texture is a means of controlling friction and wear, but only suitable surface structure can significantly improve the friction characteristics of friction surface, extend the life, save energy and so on. So the rational design and preparation of the surface texture is critical to the friction behavior of friction surface. In this paper, the molding process induced by electric field and the friction behavior of the polymer surface was studied.The micro-structure forming principle induced by the electric field was analyzed, the results show that voltage, the initial polymer thickness and air gap are the key parameters. The results of rnumerical simulation by COMSOL Multiphysics show that replica velocity increases with the increase of voltage; too much PDMS initial thickness or air gap may affect the quality replica.Experimental research about electric field-induced was carried out using the electric field with smooth glass, metal optical axis and roughness specimens as templates. The results induced by smooth glass show that the radius of the columnar is proportional to the air gap, the initial polymer thickness, and is inversely proportional to the voltage; the distance between the centers is inversely proportional to the voltage and the initial thickness. The results induced by metal axis show that the optical axis diameter can affect the final structure induced by electric field. The results induced by graphical template show that surfaces with different micro textures can be induced by controlling the voltage, the initial thickness and air gap.Dry friction behavior of PDMS surfaces induced by electric field was studied by using friction and wear tester. The results of the tests show that the columnars induced by a smooth glass increase the friction coefficient of PDMS surface and the textures induced by graphical template reduce the friction coefficient. Wettability of PDMS surfaces induced by a smooth glass was studied by using contact angle meter. The results of the tests show that the columnars weaken the hydrophobic of PDMS surface.