Frictional properties of plants-derived polyamide against surface microstructures of metal counterpart fabricated by femtosecond laser

Abstract

The purpose of this study is to investigate the frictional properties of the plants-derived polyamide 11 (PA11) against microstructures on the metal counterpart fabricated by femtosecond laser in order to control the frictional properties of polymeric materials. This study discusses the frictional properties in terms of various factors: microstructure pattern, sliding direction, sliding speed and so on. The material used in this study was plants-derived polyamide (PA). Plants-derived PA was extruded by a twin screw extruder and injection-molded. Surface microstructures on SUS304 were fabricated by femtosecond laser. This SUS304 with microstructures using femtosecond laser was used as counterparts. Tribological properties were measured by a pin-on-plate type reciprocating-sliding wear tester under oil lubrication conditions. It was found that the frictional coefficient differs according to the type of the direction of microstructures on SUS304 and with or without microstructures. The frictional coefficient of PA11 against various microstructured SUS304 decreases in the following order: Textured (MD) > Non-textured > Textured (TD). The effect of sliding speed on the frictional coefficient decreases with increasing sliding speed. The frictional coefficient of PA11 against Textured (TD) is lower than that of Non-textured in wide sliding speed region. However, the wear loss of PA11 against Textured (TD) is heavier than that of Non-textured although the effect of sliding speed on the wear loss shows the complex behavior. These results may be attributed to the change in the mode of friction and wear mechanism by the microstructures. © 2017 Author(s).