scholarly journals INTERFACES IN SiC FIBER-REINFORCED GLASS-CERAMIC COMPOSITES

1990 ◽  
Vol 51 (C1) ◽  
pp. C1-879-C1-883
Author(s):  
L. MAZEROLLES ◽  
D. MICHEL ◽  
L. ULMER ◽  
J. L. PASTOL ◽  
M. PARLIER ◽  
...  
Keyword(s):  
Glass Ceramic ◽  
Ceramic Composites ◽  
Fiber Reinforced ◽  
Sic Fiber

scholarly journals The Influence of Fiber/Matrix Interface on the Mechanical Behavior of Nicalon SiC Fiber Reinforced Glass-Ceramic Composites

1996 ◽  
Vol 458 ◽  
Author(s):  
Y. M. Liu ◽  
T. E. Mitchell ◽  
H. N. G. Wadley
Keyword(s):  
Glass Ceramic ◽  
Close Relation ◽  
Ceramic Composites ◽  
Elastic Stiffness ◽  
Ultrasound Wave ◽  
Fiber Reinforced ◽  
Ultrasound Technique ◽  
Sic Fiber ◽  
Matrix Cracks ◽  
Stiffness Constant

ABSTRACTThe mechanical properties of unidirectional Nicalon SiC fiber reinforced calcium aluminosilicate (CAS/SiC) and magnesium aluminosilicate (MAS/SiC) glass-ceramic composites have been investigated by tensile testing and a nondestructive laser-ultrasound technique. The barium-stuffed MAS was either undoped or doped with 5% borosilicate glass. The degradation of the elastic stiffness constant Cu in the transverse direction due to interface damage was monitored in-situ by measuring the laser-generated ultrasound wave velocity. The three composite materials show distinctly different macroscopic deformation characteristics, which are correlated strongly to the interface degradation. A stronger reduction trend of the elastic constant ?? is associated with a larger degree of inelastic deformation. Observations of the fracture surfaces also reveal the close relation between fiber pullout length and interfacial characteristics. Interfaces of these composites have been studied by TEM, and their influence on inhibiting and deflecting matrix cracks is discussed.

Effect of processing temperature on interfacial layer formation in SiC fiber-reinforced glass-ceramic composites

1992 ◽  
Vol 50 (1) ◽  
pp. 62-63
Author(s):  
Hyun-Ho Shin ◽  
Yolande Berta ◽  
Robert F. Speyer
Keyword(s):  
Glass Ceramic ◽  
Hot Pressing ◽  
Interfacial Layer ◽  
Interfacial Shear Strength ◽  
Ceramic Composites ◽  
High Fracture Toughness ◽  
Fiber Reinforced ◽  
High Fracture ◽  
Pressing Temperature ◽  
Sic Fiber

The high fracture toughness and non-catastrophic fracture behavior of fiber-reinforced ceramic matrix composites are due to the weak interfacial shear strength between fiber and matrix, permitting fiber-matrix sliding during failure. In SiC fiber-reinforced glass or glass-ceramic composites, such low interfacial shear strength is obtained by the presence of a carbon-rich interfacial layer. This provides a path for crack propagation, fiber pull-out, and fiber delamination during fracture. Hence, these composites have demonstrated very high fracture toughness (critical stress intensity factor of ∼ 17 MPam1/2) and high fracture strength (3 to 4 times larger than that of monolithic glass or glass-ceramics). The carbon-rich interfacial layer in these glass or glass-ceramic composites is formed by oxidation of the SiC fiber by the oxide matrix during hot pressing. Its thickness is governed by hot pressing time, temperature, and pressure. In our results on Nicalon SiC fiber-reinforced lithium aluminosilicate glass-ceramic composites, hot pressing temperature governed not only the thickness of the interfacial layer, but also the phases residing within it. In this paper, the effect of hot pressing temperature on the phases formed in the interfacial area is described.

Flexural Creep of Coated SiC-Fiber-Reinforced Glass-Ceramic Composites

1995 ◽  
Vol 78 (5) ◽  
pp. 1233-1239 ◽  
Author(s):  
Ellen Y. Sun ◽  
Steven R. Nutt ◽  
John J. Brennan
Keyword(s):  
Glass Ceramic ◽  
Ceramic Composites ◽  
Fiber Reinforced ◽  
Sic Fiber ◽  
Flexural Creep

The complexity of the matrix micro structure in SiC-fiber-reinforced glass ceramic composites

1995 ◽  
Vol 15 (12) ◽  
pp. 1235-1247 ◽  
Author(s):  
Franck Doreau ◽  
Hélène Maupas ◽  
Dominique Kervadec ◽  
Pierre Ruterana ◽  
Jean Vicens ◽  
...  
Keyword(s):  
Glass Ceramic ◽  
Ceramic Composites ◽  
Fiber Reinforced ◽  
Micro Structure ◽  
Sic Fiber ◽  
The Matrix

Fiber Coatings for SiC-Fiber-Reinforced BMAS Glass-Ceramic Composites

1997 ◽  
Vol 80 (1) ◽  
pp. 264-266 ◽  
Author(s):  
Ellen Y. Sun ◽  
Steven R. Nutt ◽  
John J. Brennan
Keyword(s):  
Glass Ceramic ◽  
Ceramic Composites ◽  
Fiber Reinforced ◽  
Sic Fiber ◽  
Fiber Coatings

Monitoring Damage in Non-Oxide Composites at High Temperatures Using Carbon-Containing CVD SiC Monofilament Fibers As Embedded Electrical Resistance Sensors

2020 ◽  
Author(s):  
Ragav P. Panakarajupally ◽  
Joseph Elrassi ◽  
K. Manigandan ◽  
Yogesh P. Singh ◽  
Gregory N. Morscher
Keyword(s):  
Crack Growth ◽  
Electrical Resistance ◽  
Composite System ◽  
Elevated Temperatures ◽  
Ceramic Composites ◽  
Fatigue Tests ◽  
Matrix Cracking ◽  
Fiber Reinforced ◽  
Damage Initiation ◽  
Sic Fiber

Abstract Electrical resistance has become a technique of interest for monitoring SiC-based ceramic composites. The typical constituents of SiC fiber-reinforced SiC matrix composites, SiC, Si and/or C, are semi-conducive to some degree resulting in the fact that when damage occurs in the form of matrix cracking or fiber breakage, the resistance increases. For aero engine applications, SiC fiber reinforced SiC, sometimes Si-containing, matrix with a BN interphase are often the main constituents. The resistivity of Si and SiC is highly temperature dependent. For high temperature tests, electrical lead attachment must be in a cold region which results in strong temperature effects on baseline measurements of resistance. This can be instructive as to test conditions; however, there is interest in focusing the resistance measurement in the hot section where damage monitoring is desired. The resistivity of C has a milder temperature dependence than that of Si or SiC. In addition, if the C is penetrated by damage, it would result in rapid oxidation of the C, presumably resulting in a change in resistance. One approach considered here is to insert carbon “rods” in the form of CVD SiC monofilaments with a C core to try and better sense change in resistance as it pertains to matrix crack growth in an elevated temperature test condition. The monofilaments were strategically placed in two non-oxide composite systems to understand the sensitivity of ER in damage detection at room temperature as well as elevated temperatures. Two material systems were considered for this study. The first composite system consisted of a Hi-Nicalon woven fibers, a BN interphase and a matrix processed via polymer infiltration and pyrolysis (PIP) which had SCS-6 monofilaments providing the C core. The second composite system was a melt-infiltrated (MI) pre-preg laminate which contained Hi-Nicalon Type S fibers with BN interphases with SCS-Ultra monofilaments providing the C core. The two composite matrix systems represent two extremes in resistance, the PIP matrix being orders of magnitude higher in resistance than the Si-containing pre-preg MI matrix. Single notch tension-tension fatigue tests were performed at 815°C to stimulate crack growth. Acoustic emission (AE) was used along with electrical resistance (ER) to monitor the damage initiation and progression during the test. Post-test microscopy was performed on the fracture specimen to understand the oxidation kinetics and carbon recession length in the monofilaments.

Sign in / Sign up

Export Citation Format

Share Document