Preparation and Characterization of Axial Gradient Silicon Carbide Fibers with  Sinusoidal Electrical Resistivity

Silicon carbide (SiC) composites are receiving much attention for structural use at high temperatures. One class of composites are those reinforced with SiC fibers. The SiC fibers are coated with boron nitride (BN) which is weakly bonded to the fiber. During fracture, the coating deflects cracks causing pull-out of the fibers (Fig. 1). This process of fiber pull-out consumes energy and increases the toughness of the composite. Although much work has been done on characterizing these materials by SEM, not much has been done using TEM due to difficulties in specimen preparation. The purpose of this study is to characterize these fibers and composites using conventional and analytical TEM.In this study, TEM specimens were prepared by dimpling and ion milling. Careful control of the preparation was needed to ensure the integrity of the SiC-BN interface. Figure 2a is a TEM image of the fiber showing delamination at the SiC-BN interface.

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Axial graded silicon carbide fibers with fluctuating carbon layer and sinusoidal electrical resistivity

Materials Letters ◽

10.1016/j.matlet.2011.05.058 ◽

2011 ◽

Vol 65 (17-18) ◽

pp. 2562-2564 ◽

Cited By ~ 8

Author(s):

Tian-jiao Hu ◽

Xiao-dong Li ◽

Yi-he Li ◽

Hao Wang ◽

Jun Wang

Keyword(s):

Silicon Carbide ◽

Electrical Resistivity ◽

Carbon Layer ◽

Silicon Carbide Fibers

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Processing and characterization of cobalt silicide nanoparticle-containing silicon carbide fibers through a colloidal method and their underlying mechanism

Journal of Materials Chemistry C ◽

10.1039/c4tc00315b ◽

2014 ◽

Vol 2 (25) ◽

pp. 4980-4988 ◽

Cited By ~ 9

Author(s):

Liu Anhua ◽

Chen Jianming ◽

Ding Shaonan ◽

Yao Yanbo ◽

Liu Ling ◽

...

Keyword(s):

Silicon Carbide ◽

Underlying Mechanism ◽

Cobalt Silicide ◽

Sic Fibers ◽

Silicon Carbide Fibers ◽

Colloidal Method

Cobalt-containing silicon carbide (Co–SiC) fibers were synthesized through a colloidal method.

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Electrical resistivity characterization of silicon carbide by various methods

2012 IEEE International Symposium on Electrical Insulation ◽

10.1109/elinsl.2012.6251423 ◽

2012 ◽

Cited By ~ 3

Author(s):

C. Vanga Bouanga ◽

S. Savoie ◽

M. F. Frechette ◽

H. Couderc ◽

E. David

Keyword(s):

Silicon Carbide ◽

Electrical Resistivity

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Synthesis and characterization of polysilane precursors for silicon carbide fibers

Journal of Materials Research ◽

10.1557/jmr.1995.2659 ◽

1995 ◽

Vol 10 (10) ◽

pp. 2659-2667 ◽

Cited By ~ 11

Author(s):

Wayne R.I. Cranstone ◽

Suzannc M. Bushnell-Watson ◽

John H. Sharp

Keyword(s):

Silicon Carbide ◽

Alkali Metal ◽

Gel Permeation Chromatography ◽

Thermomechanical Analysis ◽

Synthesis And Characterization ◽

Silicon Carbide Fibers ◽

Gel Permeation

A series of polysilanes was prepared by the alkali metal dechlorination of chlorosilane monomers, in which the overall functionality, F, of the reaction was varied. Starting monomers of functionality f = 2.0 and 3.0 were reacted together in various proportions to achieve values of F of 2.2, 2.35, and 2.5. In addition to varying the functionality of the reaction, three different difunctional monomers, dimethyldichlorosilane (DMDCS), diphenyldichlorosilane (DPDCS), and methylphenyldichlorosilane (MPDCS), and two trifunctional monomers, phenyltrichlorosilane (PTCS) and ethyltrichlorosilane (ETCS), were used. The effect of these changes on the yields of the polysilanes was determined, and the products were investigated by the use of thermogravimetry (TG), gel permeation chromatography (GPC), and thermomechanical analysis (TMA). The ability to spin a polysilane fiber was also assessed.

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