Shape Optimization Design Of Large Length Diameter Ratio Vibration Control Boring Bar

With the promotion of modernization and industrialization, deep hole components have more applications and functions, so their machining quality and performance requirement are higher and higher. With large length diameter ratio and low rigidity, deep hole boring bar is easy to happen chatter vibration and reduce machining quality of workpiece surface. It is need to use new dedicated and high-efficiency cutting tools to keep machining high quality, high efficiency and steady. So study of new vibration control boring bar is gradually urgent. Combining simulation with modal experiment and machining experiment, the study of relationship between boring bar shape and its dynamic characteristic is in-depth to conduct shape optimization design of large length diameter ratio vibration control boring bar. This article relates to the following:(1) With analyzing present research status of boring bar vibration control design, design progress of passive vibration control boring bar was focused on.(2) Kinetic equation of large length diameter ratio boring bar was setted up, and relation between natural frequency and damping coefficient of boring bar was deduced to analyze how boring bar quality impacts its dynamic stiffness and damping action. By the use of topologic optimization method, the distribution of removable material on the boring bar was researched with the goal of minimum static stiffness change of boring bar.(3) Combining with topologic optimization result, boring bar shape optimization design was conducted under a specific processing parameter, and four schemes of shape optimization design were gotten. Static and dynamic performance of the schemes were analyzed by using workbench software to determine the optimal shape of vibration control boring bar under the specific processing parameter. Choosing maximum deformation and natural frequency of boring bar as optimization objectives, and its main shape parameter as optimization variables, multi-objective parameter optimization was used to get the optimal shape parameter of vibration control boring bar. vibration damping performance of optimized boring bar was tested with simulation analysis of unoptimized and optimized boring bar model.(4) Topologic optimization method was used to study the impact of resultant cutting force and component cutting force on shape optimization of large length diameter ratio vibration control boring bar. Combining with impact of machining parameters on cutting force, the change rule of shape parameter of boring bar with machining parameter and workpiece material was discussed to verify the feasibility of that vibration control boring bar can be designed by using boring bar shape optimization under the different machining parameter and workpiece material.(5) Based on comprehensive consideration, a set of machining parameter was selected to conduct Modal experiment and machining experiment of one type of MITSUBISHI damping boring bar. Used the same machining parameter, the same experiments were conducted to study the self-made shape optimized vibration control boring bar, and its experimental data was used to compare with the experimental data of damping boring bar in order to evaluate vibration damping performance of self-made vibration control boring bar.