Influence Of Different Temperatures On Fretting Wear Characteristics Of Carbon Fiber Composites And Titanium Alloy

Carbon fiber composites(CFRP)and titanium alloys were widely used in aerospace fields.CFRP as structural materials of aircraft was often exposed to low temperature environment.Titanium alloys were often faced with high temperature conditions as the structural materials of aero-engines.Fretting wear was a common wear phenomenon in aerospace field which occured the nearly close matching surfaces.It changed the original size of parts,decreased the reliability of connecting parts,caused stress concentration and changed coordination precision etc.Based on this,this paper used FTM 200 friction and wear tester and selected CFRP and titanium alloy to implement fretting wear tests under high and low temperature.This paper provided basic research for fretting wear problem of related materials under certain environment.By designing and processing grip of texter and adopting Thermo Electric Cooler(TEC)and Metal Ceramics Heater(MCH),the high and low temperature test condition was achieved.The study of Fretting wear property of CFRP and TC21 and TC4-DT titanium alloys under different temperatures appraises fretting wear property of CFRP under low temperature as well as titanium alloy under high temperature.The findings were as follows:1.CFRP fretting wear test showed that under low temperature,CFRP matrix became brittle,the binding force between matrix and carbon fiber increased easily,cracks were easier to be transferred,and friction coefficient and wear extent increase.The wear mechanism of CFRP under room temperature was mainly abrasive wear while fatigue wear was mainly caused by at low temperature.With the increasing of load,the expanding speed of material’s contact area increased faster than the increasing speed of load and the friction coefficient decreased.Meanwhile,the increasing of load strengthened the stress concentration,which resulted in increasing of cracks and wear extent.2.The fretting wear test of titanium alloys under high temperature showed that the wear debris of TC21 was softened under high temperature and formed wear debris layer.The decreasing friction coefficient and increasing oxidation reaction on the surface of material easily formed the oxidation film,which restrained the adhesion wear and abrasive wear and decreased the wear extent.After heating and softening,the plastic deformation and adhesion phenomenon of material surface increased,the friction coefficient increased,and the adhesion wear and fatigue wear of material surface increased,which led to the increasing of wear extent.