PolyVinylidene Fluoride (PVDF) is a polar crystalline polymer commonly foun
d in the apolar alpha crystalline form studied here. The complementarity of
a macroscopic (tensile tests at constant crosshead speed) and a microscopi
c approach (Small-Angle X-ray Scattering and Wide-Angle X-ray Scattering) s
pecifies the cavitation phenomenon occurring in this material when strained
. Ar room temperature, microvoids nucleate predominantly in equatorial intr
aspherulitic amorphous layers, just before the yield. For further strains,
these defects grow in the tensile direction and damage affects a larger are
a of spherulites. This process, combined with classical amorphous shear mec
hanisms, prevails in PVDF deformation as crystallite fragmentation remains
of minor importance, for axial strains of up to 30%. (C) 2000 Elsevier Scie
nce Ltd. All rights reserved.