The development of a feasible method for the tribological characterization of gear teeth surface treatments

In this investigation, an experimental campaign, dedicated to the tribological characterization of surface treatments for gears, is presented. Wear in gears is herein simulated by means of a Ring-on-Ring test machine, where the ring and the cylinder are chosen in such a way that the kinematic and dynamic conditions are as much as possible similar to those presented in the teeth contact, in one of the two extreme points of the action line. The dynamics is simulated by imposing the same contact stress, while the kinematic conditions are applied by assuming in the two systems the same ratio of the specific slide rather than the same sliding speed. The latter choice is justified by the results shown in a preliminary test phase, which have shown the importance of the specific slide for the prediction of wear in gear profiles. The apparatus has shown a fair prediction capacity and has been used to compare the different wear resistances and typologies of gear pairs having different surface treatments. Results are herein presented and briefly discussed.