Effect Of Counterpart Materials On Fretting Wear Behavior Of TC4 Titanium Alloy

TC4 titanium alloy is widely used in aerospace,petrochemical,ma chinery,medical and other fields because of its high specific strength,low density and good corrosion resistance,but it is very sensitive to fretting damage,which limits its application to some extent.It is necessary to study the influence of counterpart materials on the fretting wear behavior of TC4 titanium alloy in order to slow down the fretting failure of titanium alloy.In this paper,the SRV-IV fretting friction wear tester was used to study the fretting wear of the TC4 titanium alloy with three different materials:GCr15 steel ball,Si₃N₄ ceramic ball and Al₂O₃ corundum ball at room temperature performance.After the test,the wear profile of the worn surface was observed with a scanning electron microscope,and the wear volume was measured with a three-dimensional profiler.The wear surface morphology,friction coefficient,wear volume and third body layer were compared and analyzed from TC4 titanium alloys against different counterparts after fretting wear tests.EDS composition analysis of the wear scar surface was also conducted to investigate the effect of counterpart materials on the fretting wear behavior and wear mechanism of TC4 titanium alloy.By these work,we can provide experimental data and theoretical references for the study of ant i-fretting wear failure.The main research results of this paper are as follows:?1?Under the same load,the wear mechanism differed depending on the counterpart.?2?The counterpart had a great influence on the friction coefficient.The friction coefficient of GCr15/TC4 decreased with the increase of load.The friction coefficient of Si₃N₄/TC4 decreased firstly and then increased with the increase of load.The friction coefficient of Al₂O₃/TC4 increased with the load increase.?3?The wear of TC4 titanium alloy against Al₂O₃ ceramic ball was the most serious.Under low load,the wear of TC4 titanium alloy against Si₃N₄ ceramic ball was smaller than wear of TC4 titanium alloy against GCr15 steel ball,but the reverse was true when the load was high.?4?When Si₃N₄/TC4 grinded and the load was low,the third body layer played a good role in lubrication and bearing,and can effectively reduce the wear of the TC4titanium alloy;when the load was high,the destructive speed of third body layer wa s much greater than the formation speed of the third body,and the wear debris generated by the third body damage formed wear amount s,so when the pressure which applied on the TC4 titanium alloy specimen exceeded a certain value,the wear amount would increase sharply.When Al₂O₃/TC4 grinded,wear debris the TC4titanium alloy surface was transferred to the surface of the Al ₂O₃ ball and undergone a tribochemical reaction with the Al₂O₃ ball to form a titanium-aluminum intermetallic compound.The high-hardness intermetallic compound became a sharp cutting tool,aggravating the TC4 titanium alloy.The wear volume of TC4 titanium alloy was the highest.?5?Under the 80N load,the analysis of the third body layer in the wear scar profile of the TC4 titanium alloy against the different counterpart showed that the third body layer produced by the GCr15/TC4 was loose and discontinuous and easy to separate and the third body layer easily detached from the frictional contact surface and increased the amount of wear;the third body layer produced by the Si₃N₄/TC4/was continuous and compact,which played a role of good lubrication and load-bearing and helped to reduce the wear of the TC4 titanium alloy.