A new quick-stop device to study the chip formation mechanism in metal cutting: Computational and experimental investigation

Abstract

Understanding the chip formation mechanisms during machining is an important factor to facilitate the choice of cutting tools and machining parameters. Despite the appearance of new sophisticated methods and advanced equipment, the technique so called quick-Stop Test (QST) remains efficient, less costly, and easier to apply in the investigation of chip formation in cutting process. In present paper a new Quick-Stop Device QSD is designed, numerically simulated, implemented, and tested. The reformed QST technique uses a QSD device which operates on the modified Charpy pendulum. Accordingly, design of new QSD is presented and deeply described, and 2D FE modeling of the new QST, including the application of the appropriate boundary conditions, has been carried out. Moreover, chip formation and morphology for different cutting conditions have been effectively simulated. Subsequently, quick stop cutting operations including metal cutting tests of high alloyed tool steel (AISI D2) using fabricated new QSD are performed. Preliminary results of quick-stop experiment from current investigation prove the effectiveness of the new designed QSD in matter of rigidity, safety, and absence of vibration, while providing a fast set up time and allowing extremely short workpiece-cutting tool separation time and guarantee the generation of chip with its root. The photomicrographs of chip root samples gathered from hard metal cutting experiments including various cutting speeds machining conditions, enables clear observation of segmented chip formation mechanisms, thereby, highly promising the new designed QSD for the purpose of investigation of the different cutting parameters influencing the chip formation and morphology.