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This report describes the monitoring of bimetal aluminum/ steel bearings by means of the vibration analysis method, in particular for purposes of detection of fatigue failures in the bearing contact layer. A built-in measurement system is used on a plain bearing test rig, continuously analyzing machine vibrations at the bearing locations and comparing them to a reference state. This practice is based on the principle that a change in the surface characteristics of a hydrodynamic bearing also causes change in the spring and damping characteristics of the vibration absorbing elements. Thus, from the changes in the vibration transfer characteristics of the bearing, the condition of the bearing surface can be indirectly assessed. The fundamental principles of plain bearing vibration transfer behavior, the mathematics of the monitoring system, and the application of the system to a test rig are described in detail. The results demonstrate the successful application of the system.

The objectives for the development of a new high strength aluminium based bearing material are explained. To satisfy these objectives a new material was developed and the composition and structure of this material are described. In the initial phase of development the material successfully passed different internal tests, which are described in the article. However, tests by engine manufacturers indicated a tendency to seizure problems. To study this performance characteristic a test procedure was developed, which allowed a better evaluation of the seizure properties. With use of this test procedure, the composition of the new material and the bearing production process were able to be modified such that resistance to seizure was significantly increased. The composition and the structure of this new material, AlSn10Ni2MnCu, is described and the manufacturing process briefly explained.