  For conventional plate and disc layered magnetoelectric (ME) composites, the
ME effect appeared under low bias magnetic fields, which caused by line
magnetostriction. In this paper, we present a new structure ME composites,
cylindrical bilayered composites. Unexpectedly, the ME effect also appeared
under high magnetic fields in this cylindrical bilayered Ni-lead zirconate
titanate (PZT) composite. We thought this ME effect caused by volume
magnetostriction. The results showed that the ME voltage coefficient of the
cylindrical bilayered composite of Ni-PZT was the sum of aE(l) caused by line
magnetostriction under low bias fields and aE(w) induced by volume
magnetostriction under high fields. At the resonance frequency, aE,A(w)
increased linearly with bias magnetic field HDC to 30 V/cm Oe at HDC =8 kOe,
and was much larger than aE,A(l) at Hm=0.6 kOe. The novel characteristic of ME
voltage coefficient increased linearly with the rise of HDC after 1 kOe in
axial mode makes the cylindrical composite a promising candidate for
application in high magnetic field sensor.
