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The macroscopic properties of ferroelectric materials depend directly on the domain configuration and the structure of the domain boundaries. For this reason, their study is of great scientific and technological interest. Several models have been developed ...
The materials used for cutting tool applications are principally divided in two classes: the WC-Co cemented carbides, tough but with a limited resistance to deformation at high temperature, and the TiCN-Mo-Co cermets, more refractory but less tough than th ...
CuGeO3 undergoes a transition from a spin-Peierls phase to an incommensurate phase at a critical field of H-c approximate to 12.5 T. In the high-field phase a lattice of solitons forms, with both structural and magnetic components, and these have been stud ...
The ac field dependence of dielectric response of sol-gel derived Pb(Zr, Ti)O-3 thin films is presented. The analysis of amplitude and phase angle of first and third harmonic of the polarization at subswitching fields shows that a description of the dielec ...
The contribution of domain walls to the dielectric permittivity of ferroelectrics is customarily explained by the model of locally pinned walls. Here we analyze the complementary case and calculate wall contribution to permittivity of a sample in which 180 ...
The contribution from the irreversible displacement of non-180 degrees domain walls to the direct longitudinal piezoelectric d(33) coefficient of BaTiO3 and Pb(Zr,Ti)O-3 ceramics was determined quantitatively by using the Rayleigh law. Effects of the cryst ...
The ac field dependence of dielectric and piezoelectric response of sol-gel derived Pb(Zr,Ti)O(3)thin films is presented. The nonlinear response of dielectric polarisation and piezoelectrically induced strain at sub-switching fields was studied in terms of ...
Through the use of relations analogous to that of the Rayleigh law, it is demonstrated that the ac electric field dependence of the permittivity of ferroelectric thin films can be described. It is further shown that both reversible and irreversible compone ...
The dislocation structures resulting from compression tests on Ni-3 (Al, I-If) single crystals are studied as a function of the deformation temperature between 77 and 900 K. Mechanical parameters are also reported, such as the 0.2% offset stress, the work- ...
It is shown that at weak alternating stress the relationship between the piezoelectrically induced charge and applied stress in ferroelectric ceramics has the same form as the Rayleigh law for magnetization versus magnetic field in ferromagnetic materials. ...
