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& The miniaturization of cutting processes shows process specific size-effects like the exponential increase of the specific cutting force k c with decreasing depth of cut h. Experiments were carried out in an orthogonal turning process. The influence of different process parameters on the results was investigated separately to identify process specific size-effects. Two materials were studied: a normalized steel AISI 1045 and an annealed AISI O2. To complement the experiments, parameter variations were performed in two-dimensional, thermo-mechanically coupled finite element simulations using a rate-dependent material model and analyzed by similarity mechanics. The influence of rounded cutting-edges on the chip formation process and the plastic deformation of the generated surface were determined numerically. The complex physical effects in micro-cutting were analyzed successfully by finite element simulations and compared to experiments.

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Manufacturing of ceramic and metallic micro components in micro powder injection moulding (lPIM) requires mould inserts offering high wear resistance and a sufficient demoulding behaviour. Within the frame of this research lPIM mould inserts made from low and high alloyed tool steel were structured by micro milling and finished by micro peening and ultrasonic wet peening. Influence of surface condition on wear and demoulding behaviour of the steels in lPIM with ceramic feedstock was characterized using a laboratory tribotester simulating powder injection moulding and a specially adapted static friction tester. Results indicate that performance of mould inserts in micro powder injection moulding depends not only on hardness, surface condition and homogeneity of the mould insert materials but also is strongly influenced by the characteristics of the feedstock, like composition of the binder or amount and hardness of the ceramic particles.