Tribological Characteristics Of Surface Microstructures Under Different Experimental Conditions

The microstructures such as dimple, groove and meshwork were fabricated on the Ti alloysurface, then DLC and CrN coatings were deposited on the surfaces of microstructures. The frictionand wear properties of the surface microstructures and coupling surfaces sliding against Si₃N₄ballwas studied by changing the solution, load, or velocity. The microstructures were fabricated on thesurface of Ultrasonic Motor stator, and the influence of tribological characteristic of Ultrasonic Motorstator on the microstructures was studied. The main researches and results were showed as follows:Firstly，the friction factor of the surface microstructures/DLC film in cutting fluid were higherthan the other two kind of solution, and wear rate of the ball was the most serious when the dimplesurfaces/CrN film slided against the ball in sea water, and the reason was that the depth of the dimplewas shallow and the ability of storing impurities reduced, so three body wear was intensified; Thefriction factor of the surface microstructures/films reduced gradually with the increasing of the load;With the increasing of velocity, the friction factor of surface microstructures/DLC film reducedgradually, and the wear rate of Si₃N₄ball increased gradually, while wear rate of the ball was the mostserious, when surface microstructures/CrN film slided with the Si₃N₄ball in low speed conditions.Secondly, the friction factor of the dimple is lowest, at0.3or so, when θ angle is75°and frictionfactor is the highest,about0.5, when angle is15°,30°; The effect of reducing friction is worst when θangle is15°on the groove microstructure, and in θ angle for90°the stable friction factor is about0.54,while the friction and wear properties of the groove microstructure in θ angle for90°was better thanother angle; The friction factor of mesh microstructure in θ angle for90°was highest, at the sametime the wear of Ti alloy disk and the ball was lower than the other θ angle; theoretical analysis found,with the increase of θ, the pressure decrease gradually, and in θ for75°, the pressure began to rise.Thirdly, friction factor of ultrasonic motor stator surface was more stable than smoother surfacewhen microstructure surface is fabricated, and when width of0.15mm, area rate of30%, the width of0.2mm, area rate of20%and the width0.25mm, area rate of25%area, not only the the friction factorof groove microstructures were smoother than smooth surface, but output force of the motor is higherthan smooth surface, while output force of the motor is lower than smooth surface when the dimplewas fabricated on ultrasonic motor stator surface; the wear rate of motor stator surface is significantlylower than smooth surface because the surface microstructures was fabricated on linear ultrasonicmotor stator surface.