During turning of hard metals, cutting heat causes thermo-elastic deformation of the workpiece which results in shape- and dimension deviations. In order to minimize these deviations, control of thermo-elastic deformation is required. The prerequisite for this is knowledge of the influence-cause-effect relationship and the ability to predict workpiece behaviour. For this reason, the workpiece is modeled by means of the finite element method (FEM) and temperature and deformation are simulated by parameter selection. Results of the finite element calculations are compared with results of experimental investigations.