Series: Materials Science and Technologies
BISAC: TEC027000

The advanced materials and devices based on nanotechnology and piezoelectric approaches have found wide applications in modern science and techniques. Tremendous interest to similar studies is supported owing to fast improvement of theoretical, experimental and numerical methods. These achievements expand scientific knowledge on the physical world and provide a forecast on the development of very fine processes and transformations occurring during processing, loading and work of modern materials and devices under critical conditions. The considered specimens demonstrate a broad spectrum of properties in scale from nanometers up to macroscopic range.

The discussed devices and goods possess very high accuracy, longevity and extended possibilities to work in wide temperature and pressure ranges; they demonstrate characteristics directly defined by developed compositions, technical and technological solutions.

This book is divided into nine chapters, devoted to:

(i) the imitation of strengthening processes of the grain borders based on the model polyatomic clusters consisting of atoms of iron and other elements; the used quantum-chemical approach allows us to systematize atomic interactions on the grain-boundary surfaces, estimate the compatibility of various elements with iron on these surfaces, and connect this compatibility with the Mendeleev’s periodic law; the calculation results are compared with the known experimental data and confirmed with the researches performed by using the methods of Auger and X-ray electron spectroscopy;

(ii) the experimental investigations, mechanism and methods of formation process of SiO2 nanofilms (applied in the technology of formation of microfluidic structures of hybrid systems) on the surfaces Si and SiC with presentation of technical solutions and equipment for the formation of nanosized silicon dioxide films;

(iii) the theoretical and experimental studies of the properties of the nanoscale layered aluminum silicates when they are intercalated by metal ions; the sorption capacity, mechanical and electrical properties are studied with a comparison of theoretical calculations performed by the methods of molecular modeling using density functional theory and molecular dynamics; these comparative results reveal correlations of micro- and macro-properties of the samples;

(iv) the mathematical simulation of the stress and bubbles formation in sapphire crystals with consideration of the heat and mass transfer at all stages of sapphire crystal production by estimating the large number of influence factors on crystal growth and quality and determining the main causes of the defect structure formation in the solid phase;

(vi) the consideration of ceramics as physical objects on the base of statistical approach; the studied objects are the macro- and microheterogeneous (colloidal) ceramic materials with different types of microheterogeneity (crystal-layer in the ferroelectric ceramics and antiferromagnetic – ferromagnetic separation in multiferroics); the phenomena of dielectric relaxation and retardation, electric effects are described together with crystallographic characteristics of specific multicomponent compositions;

(v) the generalized model of the piezoelectric medium with damping properties and the Cowin-Nunziato model of the elastic medium with voids, used for piezoelectric bodies; formulations of the constitutive equations and finite element approximation in the expanded and reduced forms are present and natural frequencies and eigenvectors for piezoelectric bodies with voids for different boundary conditions are studied; the efficiency of the proposed model and finite element approximations is verified by analyzing a focusing spherical device from porous piezoceramics emitting ultrasonic waves in surrounding acoustic medium;

(vii) the methods for online estimation of the frequency and envelope signals and some features of its implementation; the comparative analysis of their accuracy and statistical characteristics, as well as guidance on the application of these methods to study the properties of quartz oscillators are presented;

(viii) the fundamental restrictions for quality of piezoelectric devices and estimation of standard quantum limits for the measurement error of electromagnetic oscillations in piezoelectric devices; the methods of advancing phase and frequency stability for oscillations in piezoelectric resonators are discussed with obtainment of the lower limit for an estimated error of signal parameters in resonators and filters on the base of the Rao-Kramer inequality. (Imprint: Nova)