Manufacturing problems of sandwich composite structures

Sandwich composites have attracted a lot of attention in the past decade, and the significance of this new type of structure is indisputable. These materials have exceptional mechanical properties, and they seem to be the key to achieving the latest environmental objectives. The aviation and the automotive sectors have implemented composite structures in their designs because of their lightweight nature and considerable energy absorption property. Many types of sandwich structures can be observed in the industry. Still, one of the most important types is the honeycomb sandwich structure which combines a honeycomb-resembling core made of lightweight material, often aluminium, with fiber-reinforced plastic sheets as facings. In this paper, an overview of sandwich composite structures is presented, highlighting their cutting problems, and a structure under development is introduced. This structure has been designed and manufactured to research the machinability of sandwich structures in milling and scoring operations. Furthermore, the planned process for machining is discussed. In addition, milling tests were carried out with a unique honeycomb milling cutter with a total depth of cut to simulate the practical application of such a material. The milling experiments were designed and analysed according to the Design of Experiment (DOE) method.