Friction performance of DLC film textured surface of high pressure dry gas sealing ring

Abstract

After applying the diamond-like carbon (DLC) coating and surface micro-texturing into dry gas seal, the friction performance of textured surface DLC film of high pressure dry gas sealing ring has been researched in this paper. Firstly, the variation curves of friction coefficient with different load, rotation speed, and micro-texture geometric parameters are measured by using end-face friction and wear experiment machine (HDM20) under dry friction condition. Secondly, in order to compare the wear condition, the surface morphology of pretest and posttest is analyzed by using three-dimensional non-contact surface topography instrument (ST400). The experiment results show that: (1) The seal face which exists micro-textured DLC film has low friction coefficient, (2) under the same condition of micro-textured parameters, the friction coefficient would decrease with the increase in the load and would decrease firstly and then increase with the increase in the rotation speed, and (3) under the same running condition, the friction coefficient would decrease with the diameter of micro-pit and would increase with the increase in the density of textured area; however, the changing degree of friction coefficient would decrease. The experiment results could provide foundation for researching the tribological characteristics of faces of dry gas seal and optimizing the micro-textured structure.