growth of k2co3-doped kdp crystal from an aqueous solution and an
... coefficient. The crystal structure is tetragonal with the lattice parameters a = b = 0.7448 nm and c = 0.6977 nm. A KDP single crystal is piezoelectric at room temperature, and below 123 K (Curie point) it transforms to the ferroelectric phase and has an orthorhombic structure. This crystal is an ex ...
... coefficient. The crystal structure is tetragonal with the lattice parameters a = b = 0.7448 nm and c = 0.6977 nm. A KDP single crystal is piezoelectric at room temperature, and below 123 K (Curie point) it transforms to the ferroelectric phase and has an orthorhombic structure. This crystal is an ex ...
Revisit and insight into the dilemma of strong and brittle materials
... provide us with direct and useful images of fracture behavior and mechanisms in real polycrystals, as we know from “seeing is believing”. We can often find some useful clue and insight into a promising solution to materials problem. Figure 1 shows an example of in-situ observations of fracture proces ...
... provide us with direct and useful images of fracture behavior and mechanisms in real polycrystals, as we know from “seeing is believing”. We can often find some useful clue and insight into a promising solution to materials problem. Figure 1 shows an example of in-situ observations of fracture proces ...
Doping effects on the structural and optical properties of GaN
... (MOCVD), doped with different impurities: Mg, Si, O or C. Optical characterization was done using photoluminescence (PL), time-resolved photoluminescence (TRPL), and cathodoluminescence (CL) in-situ scanning electron microscope, whereas structural properties were studied by means of transmission ele ...
... (MOCVD), doped with different impurities: Mg, Si, O or C. Optical characterization was done using photoluminescence (PL), time-resolved photoluminescence (TRPL), and cathodoluminescence (CL) in-situ scanning electron microscope, whereas structural properties were studied by means of transmission ele ...
Determination of shear strength of unidirectional composite
... same composite material (intralaminar shear strength is a material property and should not change from test to test). A single criterion based on either stresses or strains should be able to predict the same shear strength of a particular composite using either test. This criterion can only be deter ...
... same composite material (intralaminar shear strength is a material property and should not change from test to test). A single criterion based on either stresses or strains should be able to predict the same shear strength of a particular composite using either test. This criterion can only be deter ...
Ab-initio calculations for structural properties of Zr–Nb alloys
... whereas niobium has BCC structure. Hence, it is only natural to expect that alloys Zr– x Nb will have HCP structure at low niobium concentration x whereas BCC structure will be stable for large x . Since zirconium and niobium are different only for one electron and are characterized by close package ...
... whereas niobium has BCC structure. Hence, it is only natural to expect that alloys Zr– x Nb will have HCP structure at low niobium concentration x whereas BCC structure will be stable for large x . Since zirconium and niobium are different only for one electron and are characterized by close package ...
Structure and Mechanical Properties of Fe-Mn Alloys
... problems in a different way, for example, in terms of energies. He is a very thoughtful and considerate professor, and was always there when I need the help. It has been an unforgettable experience in which he advised and helped me to build up the thermal system. It has been his knowledge, optimism a ...
... problems in a different way, for example, in terms of energies. He is a very thoughtful and considerate professor, and was always there when I need the help. It has been an unforgettable experience in which he advised and helped me to build up the thermal system. It has been his knowledge, optimism a ...
High-Electron-Mobility SiGe on sapphire substrate for fast
... rapidly and they often become poly-crystal with many defects in the middle SiGe composition. In spite of the high mobility of Ge, the mobility of SiGe layer is substantially lowered due to the formation of strain caused dislocation defects. The strain caused dislocation defects occur due mainly to t ...
... rapidly and they often become poly-crystal with many defects in the middle SiGe composition. In spite of the high mobility of Ge, the mobility of SiGe layer is substantially lowered due to the formation of strain caused dislocation defects. The strain caused dislocation defects occur due mainly to t ...
THE EFFECT OF CRYSTALLOGRAPHIC ORIENTATION ON
... The elastic modulus does not vary as a function of crystallographic direction on this face. The elastic modulus in the [110] and [112] directions is 170 GPa. The [011] and [101] directions are at angles of 60 and 120 degrees, respectively....................18 Figure 2.11: Relative shear occurring b ...
... The elastic modulus does not vary as a function of crystallographic direction on this face. The elastic modulus in the [110] and [112] directions is 170 GPa. The [011] and [101] directions are at angles of 60 and 120 degrees, respectively....................18 Figure 2.11: Relative shear occurring b ...
Heterogeneous Nanonucleants - Manuscript - FINAL
... aided the insight into the role of nucleant surface properties in controlling nucleation are presented. Selected literature also highlights mechanisms by which interfacial properties governing heterogeneous nucleation, presenting opportunities for targeted/selective nucleation by specifically design ...
... aided the insight into the role of nucleant surface properties in controlling nucleation are presented. Selected literature also highlights mechanisms by which interfacial properties governing heterogeneous nucleation, presenting opportunities for targeted/selective nucleation by specifically design ...
Significance of grain boundaries for transport phenomena in
... Grain boundaries can have a significant influence on the properties of polycrystalline materials. When determining the type and extent of this influence it is frequently useful to employ computational methods such as density functional theory and molecular dynamics, which can provide models of the g ...
... Grain boundaries can have a significant influence on the properties of polycrystalline materials. When determining the type and extent of this influence it is frequently useful to employ computational methods such as density functional theory and molecular dynamics, which can provide models of the g ...
Short-time Dynamics of Frictional Strength in Dry Friction
... It is important to note that, due to the long and narrow aspect ratio of our top block, the dynamics along the interface were essentially one-dimensional [9]. Thus, measuring the slip and local contact area as function of x and t, is well justified. For sufficiently high applied loads, the surfaces ...
... It is important to note that, due to the long and narrow aspect ratio of our top block, the dynamics along the interface were essentially one-dimensional [9]. Thus, measuring the slip and local contact area as function of x and t, is well justified. For sufficiently high applied loads, the surfaces ...
Operator Generic Fundamentals Material Science
... Line Imperfections – Edge Dislocations • Consist of an extra row or plane of atoms in the crystal’s structure • Imperfection may extend in a straight line through the crystal or follow an irregular path • May be short, extending only a small distance into the crystal and causing a slip of one atomic ...
... Line Imperfections – Edge Dislocations • Consist of an extra row or plane of atoms in the crystal’s structure • Imperfection may extend in a straight line through the crystal or follow an irregular path • May be short, extending only a small distance into the crystal and causing a slip of one atomic ...
Elastic response of cubic crystals to biaxial strain
... strain, however, rather thick overlayers can be grown before an instability occurs. In this case, most of the strain energy is stored in regions of the overlayer that are already bulklike, and can be estimated by studying biaxial deformations of bulk materials. In the region near the interface, the ...
... strain, however, rather thick overlayers can be grown before an instability occurs. In this case, most of the strain energy is stored in regions of the overlayer that are already bulklike, and can be estimated by studying biaxial deformations of bulk materials. In the region near the interface, the ...
Crystal Oscillator Circuit and Working
... Crystal oscillator circuit usually works on the principle of the inverse piezoelectric effect. The applied electric field will produce a mechanical deformation across some materials. It utilizes the vibrating crystal’s mechanical resonance. It is made with a piezoelectric material for genera ...
... Crystal oscillator circuit usually works on the principle of the inverse piezoelectric effect. The applied electric field will produce a mechanical deformation across some materials. It utilizes the vibrating crystal’s mechanical resonance. It is made with a piezoelectric material for genera ...
microhardness studies
... pressure is increased from 0.3 GPa to 0.45 GPa. Fig.4.3 and Fig.4.4 give the variation of microhardness with compacting pressures for the Cu2P207samples C1 and C3. In this case, for both samples, the hardness increases up to a load of about 2 N and thereafter remains steady. But Hv increases h m abo ...
... pressure is increased from 0.3 GPa to 0.45 GPa. Fig.4.3 and Fig.4.4 give the variation of microhardness with compacting pressures for the Cu2P207samples C1 and C3. In this case, for both samples, the hardness increases up to a load of about 2 N and thereafter remains steady. But Hv increases h m abo ...
Synthesis and characterization of pure and doped ZnO
... chemical reaction method. XRD and SEM analysis confirmed the formation of single phase nanoparticles of pure and doped ZnO. The Rietveld analysis of XRD pattern showed only the presence of pure wurtzite crystal structure in all the samples with an average particle size of about 40nm, which may find ...
... chemical reaction method. XRD and SEM analysis confirmed the formation of single phase nanoparticles of pure and doped ZnO. The Rietveld analysis of XRD pattern showed only the presence of pure wurtzite crystal structure in all the samples with an average particle size of about 40nm, which may find ...
Unusually Dense Crystal Packings of Ellipsoids
... which leads to a sharp increase in density for slightly aspherical ellipsoids? Our initial attempts to answer this question using global optimization have not found such a crystal packing, but have not ruled out the possibility either. Further multidisciplinary investigations are needed to answer th ...
... which leads to a sharp increase in density for slightly aspherical ellipsoids? Our initial attempts to answer this question using global optimization have not found such a crystal packing, but have not ruled out the possibility either. Further multidisciplinary investigations are needed to answer th ...
Crystallographic Anisotropy Control of n-type Bi-Te
... merit at room temperature. Since the thermoelectric properties along the a-axis is superior to those along the c-axis, the single crystal has a preferred anisotropy to increase the thermoelectric properties.3,4) The polycrystalline material fabricated via the conventional sintering method has homoge ...
... merit at room temperature. Since the thermoelectric properties along the a-axis is superior to those along the c-axis, the single crystal has a preferred anisotropy to increase the thermoelectric properties.3,4) The polycrystalline material fabricated via the conventional sintering method has homoge ...
Probabilistic multiscale models and measurements of self
... measurements under cyclic loadings, usually referred to as “self-heating tests.” This paper focuses on two models whose parameters are tuned by resorting to self-heating tests and then used to predict high cycle fatigue properties. The first model is based upon a yield surface approach to account fo ...
... measurements under cyclic loadings, usually referred to as “self-heating tests.” This paper focuses on two models whose parameters are tuned by resorting to self-heating tests and then used to predict high cycle fatigue properties. The first model is based upon a yield surface approach to account fo ...
Effect of external energy on atomic, crystalline and powder
... Abstract. Next to atoms and molecules the powders are the smallest state of matter available in high purities and large quantities. The effect of any external energy on the shape, morphology and structure can thus be studied with relative ease. The present investigation deals with the effect of a no ...
... Abstract. Next to atoms and molecules the powders are the smallest state of matter available in high purities and large quantities. The effect of any external energy on the shape, morphology and structure can thus be studied with relative ease. The present investigation deals with the effect of a no ...
Molecular beam epitaxial growth of high-quality - ETH E
... vacuum at low growth rates to simultaneously minimize the incorporation of impurities and the creation of crystal defects and to allow for atomically precise layer thickness control. We first give an insight into the physical background of two-dimensional electron systems and the special properties ...
... vacuum at low growth rates to simultaneously minimize the incorporation of impurities and the creation of crystal defects and to allow for atomically precise layer thickness control. We first give an insight into the physical background of two-dimensional electron systems and the special properties ...
ElaStic: A universal tool for calculating elastic constants from first
... Elastic properties play a key role in materials science and technology. The elastic tensors at any order are defined by the Taylor expansion of the elastic energy or stress in terms of the applied strain. In this paper, we present ElaStic, a tool which is able to calculate the full second-order elas ...
... Elastic properties play a key role in materials science and technology. The elastic tensors at any order are defined by the Taylor expansion of the elastic energy or stress in terms of the applied strain. In this paper, we present ElaStic, a tool which is able to calculate the full second-order elas ...
lithospheric strength profiles
... Equation (3) says that the higher the applied stress, the faster the material will deform. Conversely, a higher flow rate is associated with an increase in the magnitude of shear stress. The total strain is dependent both on the magnitude of the stress and the length of time for which it is applied. ...
... Equation (3) says that the higher the applied stress, the faster the material will deform. Conversely, a higher flow rate is associated with an increase in the magnitude of shear stress. The total strain is dependent both on the magnitude of the stress and the length of time for which it is applied. ...
The Effects of Misorientation Angle and Impurities on Grain
... solids by reducing the grain size and produce solids of high plasticity with materials of large grain size. It is also possible to enhance the material’s strength by re-orienting the grains to a higher angle because high angle grain boundaries are more resistant to dislocation movements than low ang ...
... solids by reducing the grain size and produce solids of high plasticity with materials of large grain size. It is also possible to enhance the material’s strength by re-orienting the grains to a higher angle because high angle grain boundaries are more resistant to dislocation movements than low ang ...
Dislocation
In materials science, a dislocation is a crystallographic defect, or irregularity, within a crystal structure. The presence of dislocations strongly influences many of the properties of materials. The theory describing the elastic fields of the defects was originally developed by Vito Volterra in 1907, but the term 'dislocation' to refer to a defect on the atomic scale was coined by G. I. Taylor in 1934. Some types of dislocations can be visualized as being caused by the termination of a plane of atoms in the middle of a crystal. In such a case, the surrounding planes are not straight, but instead they bend around the edge of the terminating plane so that the crystal structure is perfectly ordered on either side. The analogy with a stack of paper is apt: if half a piece of paper is inserted in a stack of paper, the defect in the stack is only noticeable at the edge of the half sheet.There are two primary types: edge dislocations and screw dislocations. Mixed dislocations are intermediate between these.Mathematically, dislocations are a type of topological defect, sometimes called a soliton. The mathematical theory explains why dislocations behave as stable particles: they can be moved around, but they maintain their identity as they move. Two dislocations of opposite orientation, when brought together, can cancel each other, but a single dislocation typically cannot ""disappear"" on its own.