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On the growth of the crystal under the balance of near-equilibrium conditions in the crystal growth process research and development, more research, less far from equilibrium crystal growth research and practical crystal growth is always unbalanced conditions , so the study of crystal growth far from equilibrium, more practical, and thus more and more concern. Dendrite crystals refers to a dendritic morphology, was originally used to describe the branch structure rendered in metal ingot, which formed in under conditions far from equilibrium, and prevalent in the microstructure in the field of metallurgy, a ceramic material, and volcanic In recent years, people were also observed in the organization of life to a lot of dendrite growth. Dendrite generation and its associated component segregation and structural defects will directly affect the performance of the material; singular dendrite dendrite-like structure, some of dendritic morphology may constitute a special fractal pattern, fractal growth involves non-linear the field of complex issues, none of the many theoretical issues resolved. Dendritic morphology of crystals topography, crystal growth provides a new research topic; dendrite growth process is a non-linear, non-equilibrium process, and the dendritic morphology with trees and flowers of the plant kingdom similar, indicating the inorganic sector contact with the organic sector. Research in this area may be balanced with prospective, non-equilibrium, non-linear evolution of the growth-related, this state of disorder - the orderly transformation of inanimate - a system of life into the relationship and difference, stable - unstable transition theory understanding significance. The dendrite involved petrology, crystallography, materials science, fractal science and other disciplines, theoretical research and practical application of great significance. Since the beginning of the 19th century, scholars dendrite extensive research work has focused on the study of metal, alloy material dendrite growth, which, in the determination of the morphological characteristics of dendrite growth model, dendrite has made some achievements. In comparison, non-metallic areas: the material aspects of the dendrite especially dendritic morphology; the geosciences the silicate melt dendrite less. In this paper, diopside - albite - anorthite (Di-An-Ab) ternary system for the research system to take rapid crystallization of different cooling rate dendrite, experimental select 1,4 two components, select the eight samples of research significance orthogonal polarizing microscope overall morphology, the backscattered electron photographic micro morphology observation and composition analysis of imaging, electron probe microanalysis testing, X-ray powder diffraction structural testing, laser Raman spectroscopy structural testing. Theoretical research, comprehensive research on the dendrite morphology, composition, structure, and explore the evolution of the different conditions for the formation of dendrites, dendrite formation mechanism of dendritic morphology system study provides some examples. The study reached the following conclusions: 1. Crystalline sample cooling temperature range of 1350 ℃ -800 ℃, if cooling too fast (> 10 ℃ / min), the sample is too late crystallization, the naked eye can see is a transparent glassy, ??crystalline blocks, whe polarizing microscope nor were crystalline small pieces, all glassy; cooling rate of 10 ℃ / min, sample the naked eye can see is transparent glassy crystal block whe observed under a polarizing microscope seen very few crystalline small piece distributed in a glass matrix; When the cooling rate of <10 ° C / minute (5 ℃ / min, 3 ° C / min and 1 ° C / min), the samples visually visible crystalline blocks, as a white, opaque and crystalline HEALTH LT; WP = 5 GT; length direction from the edge of the spherical sample extends to the center of the ball; When the cooling rate of 1 ℃ / min, the crystallization of all samples. The point of samples of the same ingredients, in the same cooling rate under the conditions, the sample of large spherical crystals ratio of the amount of crystallinity of the small sample to be less. No. 1 component (in diopside first crystal area) the samples 1-6,1-8,1-7 the dendrite is diopside dendrite, No. 4 ingredients (in plagioclase Shishou crystal area) the sample the 4-6,4-8,4-7 the dendrite mainly plagioclase dendrites, contrast X-ray powder diffraction patterns of plagioclase endmembers components, and ultimately determine the labradorite samples mixed with a small amount of diopside phase. 3 dendritic morphology of the different phases are very different. No. 1 ingredient point in diopside crystalline region, the samples (1-6,1-8,1-7) diopside dendrites main dendrite feathery or dendritic backbone on both sides of the rules branches, some branches there are sub-branches; 4 ingredients point in plagioclase first grain zone samples (4-6,4-8,4-7) plagioclase dendrites dendrite fiber radial or a collection of fine needle arrangement having no branching structure. The morphology of the different phases of the dendrite is completely different. The cooling rate also have an impact on dendritic morphology. When the cooling rate does not exceed 5 ° C / min, the samples of the same ingredients, cooling speed is slower, the dendrite branches. The finer, and the morphology of the dendrite becomes complicated, but still did not change the overall morphology. Cooling rate (≦ 5 ℃ / min) the overall morphology of dendrites, the samples of the No. 1 ingredient for dendritic 4 ingredients sample points for the fiber radial only affect the details of the dendrite morphology. Samples of the same ingredients point, the cooling rate is slow, a small body of the dendrite branches. Diopside dendrite, as the cooling rate becomes faster, Al instead of Si enter tetrahedron becomes more (Al atoms in the tetrahedral coefficient from 0.08? 0.12? 0.17), and Al in the silicon-oxygen backbone instead of Mg less into the octahedral (Al atoms in the octahedral coefficient from 0.42? 0.37? 0.18). Sample matrix glass ingredient No. 1 point Al mostly six ligands, rather than in place of Si into the tetrahedron. Plagioclase dendrites, Al all entered the silicon-oxygen backbone instead of part of Si4 was the fourth ligand. Moreover, the cooling rate becomes faster, Al was used in place of Si into the tetrahedral becomes large, in place of Si, Al greater extent performance of Al atoms in tetrahedral coefficient from 1.20? 1.21? 1.37 on the 4th component of the matrix glass, heating and cooling rate the faster, Al enters the tetrahedral more (Al in tetrahedral atoms coefficient from 0.60? 0.82? 1.01). Diopside dendrites, with the cooling rate decreases, diopside sticks Jingjing cell parameters a value was an upward trend in the value of b, c values ??were tested decreasing trend the β values ??tended to increase. 8. Reduce the For plagioclase dendrite, the cooling rate decreasing trend in cell parameters b, c tended to increase beta values ??tended to increase.
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