The objective of the K1 project "Advanced Bearing Technology for Large Engines" in cooperation with the LEC (www.lec.at) is to develop new sensors for the online measurement of temperature and oil pressure in bearings. Areas of application are research and development tasks in the field of combustion engines, but also the use for onboard measurement and evaluation of bearing conditions, for example in marine applications, is planned. The new measuring system consists of the measurement data acquisition, based on thin-film technology, and the data transfer by means of a telemetry system in the case of moving components. Challenges for the sensors are the very high mechanical and thermal stress as well as the difficult application possibilities. Figure 1 shows the sensor structure realized on a bearing and the structure of a thin-film sensor.  

Figure 1: Layer structure of sensor sandwich and sensor structuring

The thickness of the entire sensor structure achieved by us is less than 15µm and, due to the materials used, is able to replace the necessary diffusion barrier layer. The advantages of this construction are the measurement almost at the desired place, no change of the running surface and the detectability in case of wear of the bearing.