INFLUENCE OF RAKE ANGLE AND HARDNESS RATIO ON THE FORMATION OF DISCONTINUOUS CHIP DURING ORTHOGONAL METAL CUTTING

In the present investigation, numerical models that accurately predict the chip formation and stress profiles in the work-piece during orthogonal metal cutting were developed using the explicit finite-element method (FEM). More specifically, a damage material model was utilized to capture the work-piece chip formation and simultaneous breakage of the chip into multiple fragments. In the simulation, a rigid steel cutter of different rake angles was moved at different velocities against a stationary work-piece with significantly different hardness values at constant friction for a cutting depth of 1 mm. The variation of cutting forces, stresses and chip morphology were analyzed. The simulation results indicated that the explicit FEM was a powerful tool for simulating metal cutting operations. The rake angle and hardness ratio were found to have significant effect on the chip morphology during metal cutting. The cutting forces were also influenced by rake angle and tool/work-piece hardness ratio