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This paper describes the interdependence of additive and subtractive manufacturing processes using the production of test components made from S Al 5356. To achieve the best possible part accuracy and a preferably small wall thickness already within the additive process, a closed loop process control was developed and applied. Subsequent machining processes were nonetheless required to give the components their final shape, but the amount of material in need of removal was minimised. The effort of minimising material removal strongly depended on the initial state of the component (wall thickness, wall thickness constancy, microstructure of the material and others) which was determined by the additive process. For this reason, knowledge of the correlations between generative parameters and component properties, as well as of the interdependency between the additive process and the subsequent machining process to tune the former to the latter was essential. To ascertain this behaviour, a suitable test part was designed to perform both additive processes using laser metal wire deposition with a closed loop control of the track height and subtractive processes using external and internal longitudinal turning with varied parameters. The so manufactured test parts were then used to qualify the material deposition and turning process by criteria like shape accuracy and surface quality.

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Hybrid machining processes represent a potential approach to meeting the constantly increasing demands on cutting. In ultrasonic-assisted cutting, as a part of hybrid machining, the machining process is superimposed with a high-frequency vibration of small amplitude. This paper presents investigations on the drilling of stone materials, i.e. different granites and marble, in which this process is applied. It could be observed that the resultant forces and torques were reduced, which had already been discovered in investigations of various other materials. The influence of different parameters on the force reduction is shown, which is basically similar to the theoretical reduction of friction by ultrasound for small speed ratios d, but is considerably increased. This increase must be due to other effects. Besides the force reduction, a reduction of cratering at the drill exit can be observed. Based on the present results, definite conclusions on tool wear cannot be drawn yet.