Grinding Force Modeling And Experimental Research In Robot-assisted Belt Grinding Titanium Alloy Blade

Complex blades have been the very important key component in the area of aviation, energy and navigation. Also, their geometric accuracy and surface ability can almost determine the equipments' performance. Nowadays, after precision forged or finish milled, most of blades should be polished for better surface quality. Robot-assisted belt polishing can not only ensure the accuracy and consistency of the machined surface, but also significantly reduces the equipment cost. Because of the elastic properties of belt polishing, the interaction between grains and workpiece are mainly caused by the normal pressure, but not the cutting depth. So the normal force, polishing speed and feed rate will be regarded as the initial process parameters, and we integrate the active force feedback module into the robot-assisted polishing system to keep the normal contact force constant. The following is the main research content:First, modeled the tangential polishing force and divided it into three components, the cutting part, modeled by parallel-sided shear zone theory and takes shear strain, shear strain rate and heat softening effect into consideration; the sliding part, modeled by friction binomial theory and the frictional coefficient is considered variable, the ploughing part, determined by the coefficient of ploughing friction and the normal force. Calibrated the experimental parameters of the force model, concluded the relationship between machining parameters and the ratio of component force.Second, built the robot-assisted polishing platform, completed the constant force polishing titanium alloy test, and the relationships between cutting depth, MRR, specific energy, machined surface roughness, belt wear and the polishing parameters are concluded. Given reasonable explanations on the relationships and the experiment phenomenon.Third, selected the appropriate set of polishing parameters, completed constant force polishing experiment on a titanium alloy aviation blade. The result shows that constant normal force polishing can improve the efficiency, extend the belt life and improve the surface quality.Through the investigation above, we can further improve the realization of the polishing mechanisms and help improve the polishing accuracy of medium turbine blades and vanes aviation by optimizing the process parameters.