Figure 2. Comparison of the thickness of the metal layer having a lower yield
strength from the coefficient of mechanical heterogeneity: 1 – excluding friction
forces; 2 – taking into account friction forces; 3 – experiment
The General solution (13) with the system of equations (8) – (10) allows to
analyze the stress-strain state, kinematic and energy-force parameters of the pulling
process taking into account the friction forces 16, 17.
Numerical simulation was performed using DEFORM-3D. Ensuring accuracy is
achieved by a quasi-dynamic formulation of the problem using the true stress curve for
the metal deformation temperature specified in the table.
When modeling, it is assumed that the blank is composed of two metals, extracted
through a combined matrix (Fig. 3, 4). At the first stage, the two-layer Cup is darawed,
and at the second stage – drawing with thinning.
Figure 3. Design scheme of the
combined drawing process: І – area of
the drawing of the cup; ІІ – drawing
area with thinning;
1 – punch, 2 – matrix; 3, 4 – the
outer and inner layers of the blank,
respectively
Figure 4. The shape of the working
surface of the matrix for drawing with
thinning is given by the angle
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