In many applications of automotive and aircraft industries the use of material combinations such as compound materials made from carbon fiber reinforced plastics (CFRP) and metal materials like steel, titanium or aluminum alloys is significantly increasing. For these industries, the lightweight and mechanical properties of the reinforced plastic materials gain more and more importance. When machining material combinations, a number of distinctive material related effects occur and hamper the straight-forward implementation of machining processes. These effects mainly derive from the distinctive chipping behavior of the material combination caused by the different material characteristics. Thus, the drilling process of CFRP/metal stacks is to be regarded as a challenging task due to the requirements of machining efficiency and quality aspects. In this regard, vibration assisted drilling at low frequencies but high amplitudes opens up significant opportunities for improvements of the machining processes. The feed rate is superimposed by a controlled harmonic motion in order to create an intermittent cutting state. The potential of vibration assisted drilling lies in the reduction of cutting forces and tool wear.

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Austenitic steels are used in different areas of application where high strength and corrosion resistance are necessary at low and intermediate temperature levels. Machining these materials therefore induces high mechanical and thermal loading and reduces tool life and the overall process performance. A well-known approach to raise tool life is to dissipate the heat from the cutting edge. This paper presents some findings of a combined externally and internally cooled cutting insert compared to a solely externally cooled cutting insert.

Titanium and nickel based alloys are two types of industrially used materials. Especially in aerospace and automotive industry, the intermetallic titanium aluminides tend to replace these prevailing materials. Their density is only a half of nickel based alloys and a high strength at room temperature and hot condition is retained. But the high reaction affinity against tool materials, their low Youngs modulus and low heat conductivity cause difficulties in machining. During the machining process, low heat conductivity leads to high thermal loading of tools and therefore a well-directed cooling strategy is necessary. In this paper an overview about different cooling strategies, such as cryogenic carbon dioxide cooling and minimum quantity lubrication of the titanium aluminide Ti-48Al-2Cr-2Nb is shown. Based on a literature research and the experiments conducted in this investigation, cryogenic cooling is a reliable option for reducing toolwear.