Improvements in machine tools with respect to vibration damping

Machining is one of the most common methods of manufacture used in the world today and it is undoubtedly the most important of the basic manufacturing processes [21]. The principal methods used for performing the basic task of material removal are to bring a rotating tool into contact with a stationary workpiece, as on a milling machine, or to bring a rotating workpiece into contact with a stationary tool, as on a lathe. One of the critical parameters affecting the quality of the finished component is vibration of the cutting tool during machining.; The primary research question of this work was: Can improved tool holders be designed to reduce vibration thereby improving the workpiece quality? The hypothesis was: Increased damping in the tool holder structure can be achieved by introducing granular media. To better understand and quantify the results it was desirable to develop experimental and numerical models to represent the actual machining fixtures, thereby enabling one to comprehend the effects of the granular media damping treatment. The experimental models were found using nonlinear system identification techniques [12, 15], while the numerical models relied upon FEA methodologies. Once all appropriate modeling was completed, and then comparisons were made between standard and improved machining fixtures.