A study on the influence of water environment and the model of fuel fretting wear

Influence of water environment on fuel fretting wear is investigated by experiment with three different shapes of grid spring. It is shown that the wear in the case of water environment is severer than that in air. Metallurgical analysis is carried out by using a scanning electron microscope (SEM) to see the reason in the point of the size and the detaching mechanism of wear debris. Chemical composition of the worn area is also analyzed with the SEM. As a result, the size of wear debris in the case of water environment is larger than that in air, from which it is regarded that lubricating effect of water enables to decrease adhesion that results in the increase of relative slip motion of the contact surfaces. Nevertheless, further study is thought necessary to clarify the reason more persuasively. On the other hand, the work rate model is applied to the present wear data with shear force instead of conventional normal force. It is distinct to distinguish the difference in the wear coefficient K depending on the slip regime. In gross slip, K is much higher than that in partial slip. Therefore, it is suggested that the prevailing slip regime is to be identified to predict the fuel fretting failure