Effect of material on damping characteristics of impact mass during hard turning

Machining is a complex process in which many variables can affect the desired results. Among them, tool vibration is the most critical phenomenon, which affects the life of the cutting tool, quality of the components machined and functional behaviour of the machined tools. This tool vibration can be controlled by increasing the rigidity of the cutting tool through a damper. In this study, suppression of tool vibration during turning process was done by providing an impact mass to the turning tool holder. An impact mass made of brass, copper, aluminium and mild steel was used in this study. The size and shape of the impact mass were identified and the material that provides effective damping was determined using computational analysis. Cutting experiments were conducted to study the influence of impact mass on tool vibration during turning of hardened AISI 4340 steel using a hard metal insert with a sculptured rake face. From the computational and experimental results, it was observed that the use of impact mass on tool shank reduces tool vibration effectively.