BURR FORMATION AND FRACTURE IN OBLIQUE CUTTING

To improve productivity in the machining of parts, advanced technology for deburring becomes more important. In a computer-integrated manufa cturing system, the prediction of burr formation or fracture is requir ed. To apply a burr-formation model for orthogonal cutting to a realis tic oblique-machining case, a modified model for burr formation and fr acture in oblique cutting is developed. For the oblique-chip-formation model. Rubenstein's assumption that chip removal occurs as a result o f normal tool/workpiece relative movement is used to determine the mat erial properties of the chip and the geometry of chip formation. It is assumed that roll-over burr is always formed in the cutting direction . Thus burr formation in oblique cutting is considered as the accumula tion of burr formation in orthogonal cutting in tile cutting-direction plane. A result of the analysis is that the burr size or fracture loc ation decreases as the inclination angle of oblique cutting increases. Two kinds of burr formation or fracture are observed in experimentati on: uniform and inclined burr formation or fracture. Uniform burr form ation or fracture can be predicted using the modified model. In the ca se of inclined burr formation, the equivalent initial tool distance an d fracture location are determined using the values obtained in unifor m burr formation and the inclination stage.