deformation of the layers after drawing with thinning. It is shown that the calculated
results differ in advance from the experimental results no more than 9...11% for
different values of the coefficient of mechanical heterogeneity. The value of advance
increases with increasing difference of mechanical properties of layers.
Dawing without
thinning
Drawing with
thinning
System:
outer layer +
inner layer
Deformation
temperature,
ºС
Coefficient of
mechanical
heterogeneity of
metals
S1
/
S2
stainless steel +
aluminum
42010
0.78
brass +
stainless steel
65010
0.58
titanium +
aluminum
42010
0.42
Figure 10. Double-layer blanks BTE (cups) after drawing
It is also experimentally shown that the error in the numerical calculation of the
degree of deformation of the thickness of the layers when drawing with thinning along
the height of the Cup wall at different degrees of compression does not exceed
10...12%. The deformation of the layers at the height of the cup wall is uniform, if you
exclude the bottom part of the height 8...10 mm. the error of calculation of the thickness
layers on the analytical dependencies without the account of friction forces and
considering the friction forces relative to the experimental data does not exceed
10...14%. This value of the discrepancy between the analytical, numerical and
experimental results makes it possible to use them for practical calculations of the
process of drawing with refinement.
Metallography studies have shown that between the layers of dissimilar metals
when drawing with thinning of 50% and heating the metallic bond arises, which form
the connection layers. The results of metallographic studies of the bimetallic cup
system titanium + aluminum are shown in Fig. 11.
Analysis of the results shows that the deformation of the wall thinning 50% at the
boundary between the layers there are intermediate transition layers, which form a
mechanical connection of the layers. At smaller degrees of compression of 20% (Fig.
11 a) and 40% (Fig. 11, b) there is only physical contact of layers. The structure and
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