Evaluation of the influence of different inner cores on the dynamic behavior of boring bars

The material removal rate (MRR) must be increased in order to improve productivity in cutting operations. Here, the achievable maximum is usually limited by induced vibrations caused by dynamic load peaks in high force applications. Boring bars, typically used in internal turning processes, are characterized by a high length-to-diameter ratio, which makes them particularly vulnerable to vibrations. This paper therefore examines the influence of different inner cores inserted in boring bars, consisting of carbon fibre reinforced plastics, on the dynamic behavior using finite element analysis, experimental modal analysis and machining tests, and discusses the results in terms of increasing the MRR.