Crystal Growth Science Research Articles

Gabriel Faivre: his legacy on eutectic solidification

In the honor of Gabriel Faivre (1944-2020), I will present a review of major scientific contributions to the understanding of the dynamics of eutectic growth patterns. From the end of the 1980s, Gabriel Faivre undertook a systematic research in solidification guided by the new concepts of the nonlinear physics of out-of-equilibrium pattern formation. Drawing on his outstanding capabilities as an experimentalist, he refined the method of in situ directional solidification of model alloys. With constant reference to physics and metallurgy, he succeeded in carrying out a high-level research, keen to reach strong qualitative impact and quantitative accuracy. Gabriel Faivre made key discoveries, together with coworkers and young researchers in Paris, and in collaboration with materials scientists and physicists in France and abroad. From symmetry breaking instabilities to eutectic cells and dendrites, over rod-like and labyrinth patterns, full light has been shed onto new phenomena, fascinating to the eye and the mind. During the last decade, Gabriel Faivre mentored an in-depth analysis of interfacial-anisotropy effects on coupled-growth patterns, thus reconciliating the theories of regular eutectics and crystal-orientation dependent eutectic-grain growth. Being both a rigorous scientist and a generous colleague, he left us a vast legacy of prospective research topics in solidification and crystal-growth science. Sharing his knowledge of fine arts and humanities, Gabriel Faivre also instilled the best of intellectual thinking in those who were fortunate enough to work with him.

Laser patterning and growth mechanism of orientation designed crystals in oxide glasses: A review

There has been a great progress in the spatially selected patterning of crystals with a single crystal-like architecture by continuous wave (CW) and femtosecond (fs) pulsed laser irradiations in oxide glasses. Highly oriented crystals with different morphologies such as straight/bending/spiral lines and two-dimensional planar shapes are patterned using heat-driven type CW laser irradiations with a scanning mode. The features of the laser patterning of nonlinear optical crystals with birefringence such as β-BaB2O4, LaBGeO5, LiNbO3, and BaAlBO3F2 are focused, and the origin and mechanism of the c-axis orientation along the laser scanning direction are discussed from the viewpoints of surface energy and interfacial free energy between crystal and surrounding glassy phase. The homo-epitaxial crystal growth in the laser patterning of crystal lines and the rotation of crystal axes in ferroelastic β′-Gd2(MoO4)3 are demonstrated as unique features of the laser-induced crystallization. The laser-induced crystallization provides a new insight and more deep understanding for the nucleation and crystal growth in glasses and proposes a new crystal growth science and engineering in solid-state materials.

Self-organized homo-epitaxial growth in nonlinear optical BaAlBO3F2 crystal crossing lines patterned by laser in glass

Crystallization processing of glasses is important as a novel technique for the development of new optical materials, and laser-induced crystallization provides a new challenge in science and technology of materials. Nonlinear optical BaAlBO3F2 crystal lines with crossing, bending, and spiral shapes were patterned at the surface of 2NiO–49BaF2–24.5Al2O3–24.5B2O3 (mol%) and 2.9NiO–48.5BaF2–24.3Al2O3–24.3B2O3 (mol%) glasses by laser irradiation (Yb:YVO4 laser with a wavelength of 1080nm) and the orientation state of BaAlBO3F2 crystals was examined from birefringence image observations. The birefringence images indicate that the growth of highly c-axis oriented BaAlBO3F2 crystals follows along the laser scanning direction even if the laser scanning direction changes, and in particular the direction of the c-axis of BaAlBO3F2 crystals changes gradually at the crossing and bending points. The model of “self-organized homo-epitaxial growth” is proposed for the crystal orientation at the crossing and bending points, as a new crystal growth science and engineering beyond the wise providence of nature.

The Research Project of the Computer Centre at Gakushuin University The 7th Workshop of Mathematical Science of Crystal Growth(News of JACG)

The Research Project of the Computer Centre at Gakushuin University The 7th Workshop of Mathematical Science of Crystal Growth(News of JACG)

Charge conversion and mass transfer on surface of Al2O3 nanoparticles in Y2O3–Al2O3 colloidal system

The mixing process of Al2O3 and Y2O3 nanopowders in aqueous suspension was studied. Charge conversion on the surface of Al2O3 particles in the Y2O3–Al2O3 colloidal system was observed. Negative charges on the surface of Al2O3 particles became positive due to the assembly of Y2O3 on the surface of Al2O3 nanoparticles in the colloidal system, as shown by zeta potential analysis of Y2O3–Al2O3 colloidal systems with different Y/Al ratios. Rheological properties of the mixed powders slurries with different Y2O3 content were also investigated. XRD peaks of Al2O3 shifted towards smaller angles with increasing amounts of Y2O3 added, implying the encapsulation of Al2O3 by Y2O3via mass transport during the mixing process, as confirmed by HRTEM measurement. A mechanism was proposed for the paragenesis of mineral in this binary colloidal system. Hydrated Y2O3 with higher Ksp attaches and migrates onto the surface of another hydrated sediment Al2O3 with smaller Ksp and opposite surface charge. The mass transfer process between Y2O3 and Al2O3 nanoparticles in this binary mixture suspension is analogous to the Ostwald ripening process. This new growth phenomenon is important for the science of crystal growth as it helps boost the exploration of new mechanisms for crystal growth in various material systems and provide clear evidence for the diffusion growth of crystalline structure in a binary colloidal system.

Self-Assembly of Large Scale and High-Quality Colloidal Particle Films by Spin-Coating

Colloidal crystal has attracted much attention both in fundamental crystal growth science and optical applications. This paper reports a simple and efficiency spin-coating method to fabricate high ordered colloidal crystals which have specific structures. We used the cleaned glass slide as substrates, the well dispersity 300nm (±1.2%) polystyrene (PS) spheres aqueous suspension (6.6 wt%) to assemble, and obtained highly organized colloidal crystal thin film by controlling spin-coating condition. Mostly, we got the large area plane hexagonal structure at the first layer and tetragonal construction at the second layer. The mechanism for this stacking way was studied. The obtained thin films were demonstrated by Field emission scanning electron microscope (FESEM) and Fast Fourier transform (FFT).

計算機センター特別研究プロジェクト結晶成長の数理 第五回研究会-鏡像対称性と結晶成長-開催報告(学会活動報告)

計算機センター特別研究プロジェクト結晶成長の数理 第五回研究会-鏡像対称性と結晶成長-開催報告(学会活動報告)

Development of Crystal Growth Science and Technology as Integrated Sciences

Development of Crystal Growth Science and Technology as Integrated Sciences

計算機センター特別研究プロジェクト「結晶成長の数理」第四回研究会-水と氷-開催報告(学会活動報告)

計算機センター特別研究プロジェクト「結晶成長の数理」第四回研究会-水と氷-開催報告(学会活動報告)

計算機センター特別研究プロジェクト『結晶成長の数理』: 第二回研究会-非平衡現象としての結晶成長-開催報告(学会活動報告)

計算機センター特別研究プロジェクト『結晶成長の数理』: 第二回研究会-非平衡現象としての結晶成長-開催報告(学会活動報告)

Dendritic crystal growth in pure materials

Dendritic growth is a fundamental crystal growth phenomenon accompanying most casting and solidification processes, and, occasionally, occurring during the growth of single crystals, where it is detrimental to crystalline quality. Dendrites are the ubiquitous crystal form in freezing alloys and supercooled melts, because their shapes are most suited for efficient heat and mass transfer at small scales. Dendritic scales are typically the smallest length scales of interest in ingots and castings, typically associated with: (1) chemical processes, such as microsegregation, (2) thermal processes, for example, latent heat release, and (3) mechanical processes, for instance, the volume change during phase transformation. All of these processes operate at the dendritic solid–melt interface. Understanding dendritic growth is therefore considered essential for controlling basic solidification and crystal growth processes. A brief history of dendrites will be sketched, showing how the subject of dendritic solidification evolved to its present status as a modern sub-field of general crystal growth. The comprehensive understanding of dendrites and developing a predictive capability of practical utility to the crystal grower, however, remain as works in progress. The subject of dendritic growth will be presented on the basis of heat and mass transfer, capillarity effects at the solid–melt interface, and interfacial dynamics, including morphological stability, and side-branching dynamics. Experimental verification of dendritic scaling laws using microgravity experimentation is included as a brief attempt to encapsulate this important subject within crystal growth science.

Crystal growth science between the centuries

The major framework of crystal growth concepts and technologies was built during the 20th century. This solid framework, however, does not have enough predictive power. The lack of fundamental constants, multi-parametric experimental conditions, and complex chemistry in many systems remain obstacles to the quantitative confrontation of many key concepts with experiment, to make them predictive and to develop these concepts further. In addition, at least several generic issues should be addressed. For instance, the BCF theory is based on the assumption that thermodynamic fluctuations at steps are fast enough to generate a sufficient density of kinks for growth. However, for strongly polygonized steps this is not always the case. Also, for these steps, the Gibbs–Thomson relationship may be valid only within a very low supersaturation range. These problems are considered here. The Kossel model should be generalized for the lattices of which unit cells include several, say, n identical molecules, atoms, or ions in crystallographically inequivalent positions. In this case, only the unit cell as a whole makes a self-reproducible kink while the building blocks in the liquid or gas are the component molecules, atoms or ions. Because of this, the driving force for crystallization takes the same form as that in a system of n components. Therefore even the kink rate is proportional to Cn-Cne rather than to C-Ce where C and Ce are actual and equilibrium concentrations, respectively. Finally, the challenges of biomacromolecular crystallization are discussed. © 2001 Kluwer Academic Publishers

Defect formation during crystal growth

It is common knowledge in the science of crystal growth that increasing the crystal growth rate leads to a higher defect density. In Monte Carlo simulations of Lennard-Jones systems the same tendency can be observed. In this paper we give a few examples. Growing from an undercooled melt or a largely supersaturated vapor we obtain twin planes, inclusions, antiphase boundaries and twist planes.

Impurity blocking of growth steps: experiments and theory

According to an early model by Cabrera and Vermilyea, a low density of immobile impurities, adsorbed on a crystal surface may block step propagation completely at low supersaturations. This phenomenon of a “dead zone” for crystal growth has been studied experimentally by in situ measurements of the velocity of [100] steps on (001) K2Cr2O7 growing from aqueous solution as a function of supersaturation and temperature. Theoretical studies were carried out for [100] steps on the (001) face of a Kossel crystal, using the Monte Carlo technique. An overview of recent results and some implications for the science of crystal growth are given.

Developments of the Science of Crystal Growth

Developments of the Science of Crystal Growth

Implications of crystal growth theories for mass crystallization: Application to crystallization of sucrose

A survey of a set of growth theories as well as a discussion about the definition of the supersaturalion in a solution and the problem of growth rate dispersion arc given. Such theoretical aspects of crystal growth science may offer fundamental backgrounds for mass crystallization. Application of some of these theories to basic studies on sucrose crystallization as far as to the proposal of an innovative industrial process for sucrose production is reported in the second part of the paper.

Toshio Kuroda and The Science of Crystal Growth

Toshio Kuroda and The Science of Crystal Growth

Formation of crystals in solutions

Abstract Growth of high quality crystals has played an important role in sophisticated, modern- day technologies and in recent advances in physics. It has also provided examples in the study of self-organizing dissipative structures. This paper reviews the science of crystal growth and discusses recent data, particularly with regard to kinetics of growth and defects in crystal lattices.

Recent developments in crystal growth science

Recent developments in crystal growth science

宝石と結晶学

Gem materials are grouped into five categories: 1) Genuine natural gemstones, 2) imitation gemstones, 3) treated gemstones, 4) synthetic gemstones and 5) artificial gemstones. Diagnostic properties in identif icating and discriminating gem materials of the same species are due to the differences in crystal growth processes and conditions among gemstones of different categories. Crystallography, particularly science of crystal growth, may play important roles in this respect.