Study on material removal and cutting analysis in ball helical milling process

In the ball helical milling (BHM), when the ball end mill follows an orbital path around the center of the hole, it plunges into the workpiece material with a helical motion, and the movement of the tool is relatively complex. In order to deeply understand the material removal and cutting characteristics in the BHM process, kinematics of BHM technology is introduced first, then material removal is analyzed according to the shape and relative position relationship between the tool and the workpiece at different typical moments, material removal behavior is discussed through the cross-sectional area, and the cross-section features of the workpiece material. In addition, the change of cutting forces is analyzed through microelement force, and then entry and exit zones are discussed in detail. BHM experiments of titanium alloy were carried out; cutting forces were measured; and burrs around the hole and surface roughness of the hole are analyzed. The results show that the ball end mill can remove materials uniformly in the helical milling with stable cutting forces and high hole-making quality.