3.3. Overall evaluation of compositions
The results of individual bending coefficients obtained indicate that
for soft material in bottom layer the bendability is higher (see
Table 2). This can be explained by the fact that the soft material shows
higher deflection under tensile stress than the hard one. As a result
the deflections before reaching MOR are higher than those for inverse
compositions. Such knowledge may become the basis for laminated material
design. This way designed materials might have practical use
wherever good bendability as well as good structural strength parameters
are required.
Based on the three-layer materials, similar behavior can be observed.
In this case the composition influences both tension and compression
zones of the layered material. Another theory for three-layer materials
says that when the outer layers are of the soft material, this could be
used for cyclic load from both sides. The outer layers in this case can resist
tensile stresses better.