Microstructure Analysis of a Carbon–Carbon Composite Using Argon Ion Etching

2005 ◽  
Vol 11 (1) ◽  
pp. 46-55 ◽  
Author(s):  
Andreas Pfrang ◽  
Boris Reznik ◽  
Thomas Schimmel ◽  
Dagmar Gerthsen
Keyword(s):  
Electron Microscopy ◽  
Carbon Fiber ◽  
Confocal Microscopy ◽  
Light Microscopy ◽  
Laser Scanning ◽  
Carbon Matrix ◽  
Chemical Vapor Infiltration ◽  
Structural Units ◽  
Ion Etching ◽  
Carbon Fiber Felt

The microstructure of carbon–carbon composites obtained by chemical vapor infiltration of a carbon fiber felt was comparatively studied by reflection light microscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM), atomic force microscopy (AFM), and laser scanning confocal microscopy (LSCM). Ar+ ion etching was used to reveal and distinguish structural units of the pyrolytic carbon matrix. Mechanically polished samples, polished and subsequently ion etched samples, and fractured samples were compared. The values of surface roughness and surface height after polishing or after polishing and subsequent etching determined by AFM and LSCM correlate well with the degree of texture of the matrix layers obtained by polarized light microscopy and selected area electron diffraction. The carbon matrix is composed of structural units or “cells,” which contain a carbon fiber and a sequence of several differently textured layers around each fiber. Within high-textured layers columnar grains are well recognizable using polarized reflection light microscopy and confocal microscopy. The size of depressions within high-textured carbon layers found by AFM after ion etching correlates well with the size of differently tilted domains detected by both TEM and SEM.

A new approach to the study of apical meristem development using laser scanning confocal microscopy

1998 ◽  
Vol 76 (5) ◽  
pp. 899-904 ◽  
Author(s):  
Gordon D Lemon ◽  
Usher Posluszny
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Confocal Microscopy ◽  
Light Microscopy ◽  
Laser Scanning ◽  
Apical Meristem ◽  
Laser Scanning Confocal Microscopy ◽  
Shoot Apices ◽  
Scanning Confocal Microscopy ◽  
Scanning Electron

Epi-illumination light microscopy and scanning electron microscopy have been standard techniques for developmental studies of shoot apices. Recently, laser scanning confocal microscopy has gained popularity as a tool for biological imaging. We have adapted laser scanning confocal microscopy to study development in whole shoot apices. It was tested on angiosperm and fern apices using three fluorescent dyes; acriflavine, safranin O, and acid fuchsin, and compared with epi-illumination light microscopy and scanning electron microscopy. In all cases, acid fuchsin proved to be the best fluorochrome for examining shoot apices; having a high affinity for cell walls and nuclear material. The images produced with laser scanning confocal microscopy were sharper and clearer than images generated with epi-illumination light microscopy and scanning electron microscopy. Laser scanning confocal microscopy allows one to map patterns of cell division on the surface of an apical meristem, which is extremely difficult using other techniques such as scanning electron microscopy or epi-illumination light microscopy. Since the laser scanning light microscope records images digitally a method for digital plate production is described. Our methods can easily be applied to study the development of other plant structures on a cellular level such as root apical meristems, floral meristems, stomata, or trichomes, and reproductive organs in lower plants.Key words: confocal microscopy, apical meristem, development, fluorochrome, cytokinesis.

Light Microscopy, Confocal Laser Scanning Microscopy And Scanning And Transmission Electron Microscopy Of Cerebellar Golgi Cells.

1999 ◽  
Vol 5 (S2) ◽  
pp. 1302-1303
Author(s):  
O. Castejόn ◽  
P Sims
Keyword(s):  
Electron Microscopy ◽  
Light Microscopy ◽  
Laser Scanning ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Synaptic Connections ◽  
Teleost Fishes ◽  
Golgi Cells ◽  
Transmission Electron ◽  
Molecular Layers

The cerebellar cortex of albino mice, hamsters, teleost fishes, primates and human have been examined by correlative microscopy to study the Golgi cell soma, dendritic processes, axonal plexus and synaptic connections in the granular and molecular layers. For light microscopy (LM) toluidinc blue stained-plastic embedded scmithin sections and Golgi light microscopy preparations were used. For confocal laser scanning microscopy (CLSM) of hamster cerebellum the FM4-64 fluorescent stain was used as intracellular tracer (1). Conventional and high resolution scanning electron microscopy (SEM) of teleost fishes, primates and human were coated with gold-palladium and chromium (2). I Transmission electron microscopy (TEM). either by ullrathin sections or frccze-clching replicas, were examined to characterize synaptic connections in the granular and molecular layers. The Golgi cells appeared in the granular layer as polygonal, stellate, round or fusiform microncurons. 10-25 μm in maximal dimension, surrounded by the granule cell groups. Golgi light microscopy.

scholarly journals Ablation Behavior of the SiC-Coated Three-Dimensional Highly Thermal Conductive Mesophase-Pitch-Based Carbon-Fiber-Reinforced Carbon Matrix Composite under Plasma Flame

Materials ◽  
2019 ◽  
Vol 12 (17) ◽  
pp. 2723
Author(s):  
Chong Ye ◽  
Dong Huang ◽  
Baoliu Li ◽  
Pingjun Yang ◽  
Jinshui Liu ◽  
...  
Keyword(s):  
Carbon Fiber ◽  
Thermal Protection ◽  
Three Dimensional ◽  
Chemical Vapor ◽  
Carbon Matrix ◽  
Ablation Rate ◽  
Chemical Vapor Infiltration ◽  
Mesophase Pitch ◽  
Plasma Flame ◽  
Ablation Resistance

This study is focused on a novel high-thermal-conductive C/C composite used in heat-redistribution thermal protection systems. The 3D mesophase pitch-based carbon fiber (CFMP) preform was prepared using CFMP in the X (Y) direction and polyacrylonitrile carbon fiber (CFPAN) in the Z direction. After the preform was densified by chemical vapor infiltration (CVI) and polymer infiltration and pyrolysis (PIP), the 3D high-thermal-conductive C/C (CMP/C) composite was obtained. The prepared CMP/C composite has higher thermal conduction in the X and Y directions. After an ablation test, the CFPAN becomes needle-shaped, while the CFMP shows a wedge shape. The fiber/matrix and matrix/matrix interfaces are preferentially oxidized and damaged during ablation. After being coated by SiC coating, the thermal conductivity plays a significant role in decreasing the hot-side temperature and protecting the SiC coating from erosion by flame. The SiC-coated CMP/C composite has better ablation resistance than the SiC-coated CPAN/C composite. The mass ablation rate of the sample is 0.19 mg·(cm−2·s−1), and the linear ablation rate is 0.52 μm·s−1.

scholarly journals Synthesis, structure, and properties of carbon/carbon composites artificial rib for chest wall reconstruction

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Zhoujian Tan ◽  
Xiang Zhang ◽  
Jianming Ruan ◽  
Jiqiao Liao ◽  
Fenglei Yu ◽  
...  
Keyword(s):  
Carbon Fiber ◽  
Chest Wall ◽  
Soft Tissues ◽  
Carbon Matrix ◽  
Chemical Vapor Infiltration ◽  
Chest Wall Reconstruction ◽  
Autogenous Bone ◽  
Infiltration Process ◽  
Artificial Bones

AbstractIn this work, braided carbon fiber reinforced carbon matrix composites (3D-C/C composites) are prepared by chemical vapor infiltration process. Their composite structure, mechanical properties, biocompatibility, and in vivo experiments are investigated and compared with those of traditional 2.5D-C/C composites and titanium alloys TC4. The results show that 3D-C/C composites are composed of reinforced braided carbon fiber bundles and pyrolytic carbon matrix and provide 51% open pores with a size larger than 100 μm for tissue adhesion and growth. The Young’s modulus of 3D-C/C composites is about 5 GPa, much smaller than those of 2.5D-C/C composites and TC4, while close to the autogenous bone. 3D-C/C composites have a higher tensile strength (167 MPa) and larger elongation (5.0%) than 2.5D-C/C composites (81 MPa and 0.7%), and do not show obvious degradation after 1 × 106 cyclic tensile loading. The 3D-C/C composites display good biocompatibility and have almost no artifacts on CT imaging. The in vivo experiment reveals that 3D-C/C composites artificial ribs implanted in dogs do not show displacement or fracture in 1 year, and there are no obvious proliferation and inflammation in the soft tissues around 3D-C/C composites implant. Our findings demonstrate that 3D-C/C composites are suitable for chest wall reconstruction and present great potentials in artificial bones.

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