Effects of interfacial tribological characteristics of propeller- hub bearing with ZCuAl9Fe4Ni4Mn2 coatings on wear failure at marine environment

The wear failure of propeller- hub bearing directly affects the dynamic positioning accuracy and operational stability of controllable pitch propeller (CPP). The propeller- hub bearing was coated with a 2 mm thickness of ZCuAl9Fe4Ni4Mn2 (NAB) alloys, which investigated the effects of interfacial tribological characteristics on the wear failure. The results show that the NAB coatings wear tracks consist of the various colors of wear areas corresponding to the different wear characteristics. The wear areas are characterized by different degrees of abrasive wear, adhesive wear, oxidative wear, plastics deformation, etc. It attributes to the contact characteristics of the friction pairs, such as shearing, adhesion and fracture, which causes uncontrollable adverse effects. Moreover, the stress simulation analysis has confirmed that the local stress concentration of the contact area further deteriorates the lubricating performance. The superposition of interfacial wear caused by the marine loading and lubrication conditions seriously affects the service life of the propeller- hub bearing. Hence, the wear failure of the propeller- hub bearing with the NAB coatings is caused mainly by the lack of a continuous oil film at the friction interface.