In this presented work, the main objective is the in-process measurement of the thermal as-is state near the drilling contact zone by means of a sensor-integrated tool for single lip deep hole drilling (SLD). Additionally, the mechanical quantities feed force and drilling torque are evaluated. The process monitoring is essential to optimize the surface quality as well as the subsurface properties such as hardness and residual stresses. These quantities are strongly dependent on the thermo-mechanical as-is state in the cutting zone and in the contact zone between the guide pads and the drill hole surface. This contribution gives a project overview including the development of a sensor-integrated single lip deep hole driller for the in-process temperature measurement, the integration of sensor systems in the tool as well as the experimental investigations on the temperature, the feed force and the drilling torque during drilling of a 42CrMo4 steel. The temperature measurement at eleven positions in the driller head provides data to observe the heat generation, distribution, and flow independently from the workpiece characteristics. However, one of the greatest benefits is the non-destructive fashion of the measurement system with their sensor integrated in the tool and thus the reusability. A simulation method, which uses the experimental results as a reference, is used to predict the thermo-mechanical conditions in the contact zone of the drill head and the workpiece. The results of these thermo-mechanical process simulations and the validation of this applied FE approach using the measured quantities are presented, too. The results of this work are part of an interdisciplinary research project in the framework of the priority program "Surface Conditioning in Machining Processes" (SPP 2086) of the German Research Foundation (DFG).
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