Theoretical And Experimental Research Of Wear&Corrosion Resistance Films For Ring Traveler

As the pivotal high speed turning accessory of spinning machine, the surface performance of ring traveler attracts most attention of experts for its importance in the whole machine. The present surface treatment focuses on Ni-Co electroplating, which inevitably could cause severe pollution. This article is written in the purpose of finding the applications of the surface coating of ring traveler as well as making improvements such as searching for new treatments and coating processes of it. Bonded PTFE solid lubricant film, electroless Ni-P plating and diamond-like carbon (DLC) film have been chosen as the main research subjects in this paper. Not only their frictional and wear properties under different working conditions are systematically analyzed, but also the wear-resisting and anticorrosion capabilities as well as their internal mechanisms are thoroughly discussed.The results of the experiments show: (1) With relatively low and stable friction coefficient, bonded PTFE solid lubricant film, featuring sound anti-corrosion property, can be applied in the occasion of low-speed and high-load. (2)Under load of 60N or above, the slices come off from the Ni-P surface, whereas the coat performs rather well in the condition of low load. (3) Friction coefficient of DLC coating decreases with the increase of sliding velocity. The fact that friction-abrasion test only left slight scratches on the surface which verifies the sound anti-wear property. Furthermore, the corrosion weight loss experiment confirms that the coating witnesses the low loss rate and well anti-corrosion.The experiments on the wear-resisting and anticorrosive mechanism for the coating demonstrate that:(1) PTFE coating can form a relatively stable transfer film on friction surface because it enjoys good synergistic effect with filler such as resin. Abrasive wear and adhesive wear can be the two major abrasive styles. (2) Under high load, Ni-P plating will crack due to weakness of grain boundary. Soaked in corrosive medium of 5g/L NaCl, the surface will be passivated rapidly and form a protect film. (3) Under the instant high temperature caused by the high speed sliding, the metastable amorphous carbon will break the energy barrier and transform into stable graphite. It lubricates the coating and decreases both friction coefficient and wear rate. As an amorphous structure with certain thickness, the coat features favorable good anticorrosion capability.Out of comprehensive consideration for friction coefficient, wear rate, anti-corrosion, cost and environment, electroless Ni-P plating and DLC film can be applied to enhance the surface performance of ring traveler. In the view of economy, the performance versus price ratio of Ni-P plating is rather high, while of environment, DLC film could be the optimal choice.