Abstract: Aiming at the disc slitting process of sheet metal, a 2D model of the disc slitting process is established and the deformation and fracture process of 304 stainless steel sheet is simulated based on the Oyane ductile fracture criterion by using the DEFORM-2D finite element analysis software. The occurring and propagating of the crack, the material fracture mechanism and the topography features of the slitting surface are studied. Based on the variation of the mean stress of the sheet metal in the disc slitting process, the slitting time t1 when the maximum tensile stress occurs on the rollover, the slitting time t2 when the shearing area appears tensile stress and their difference ∆t (t2 – t1) are proposed to intuitively estimate the change tendency of the heights of the rollover and the shear area. The value of t1 and ∆t is shorter, then the heights of the rollover and the shear area are smaller. The influence law of the axial clearance between two disc cutters on the slitting surface topography is revealed. With the increase of the axial clearance, the rollover height and the tearing angle increase gradually, and the height of the shear area decreases gradually while the burr height decreases slightly at first and then increases rapidly. The finite element simulation results are in good agreement with the experimental results.

Key words: Axial clearance, Disc slitting, Finite element simulation, Mean stress, Slitting surface topography