Multi-scale Model of Residual Strength of 2D Plain Weave C/SiC Composites in Oxidation Atmosphere

Abstract

Multi-scale models play an important role in capturing the nonlinear response of woven carbon fiber reinforced ceramic matrix composites. In plain weave carbon fiber/silicon carbon (C/SiC) composites, the carbon fibers and interphases will be oxidized at elevated temperature and the strength of the composite will be degraded when oxygen enters microcracks formed in the as-produced parts due to the mismatch in thermal properties between constituents. As a result of the oxidation on fiber surface, fiber shows a notch-like morphology. In this paper, the change rule of fiber notch depth is fitted by circular function. And a multiscale model based upon the change rule of fiber notch depth is developed to simulate the residual strength and post-oxidation stress-strain curves of the composite. The multi-scale model is able to accurately predict the residual strength and post-oxidation stress-strain curves of the composite. Besides, the simulated residual strength and post-oxidation stress-strain curves of 2D plain weave C/SiC composites in oxidation atmosphere show good agreements with experimental results. Furthermore, the oxidation time and temperature of the composite are investigated to show their influences upon the residual strength and post-oxidation stressstrain curves of plain weave C/SiC composites.

Enhancing water swelling ability and mechanical properties of water‐swellable rubber by PAA/SBS nanofiber mats

“…depending on the type of nanofiber. [17][18][19][20] For example, highly elastic styrene-butadiene-styrene (SBS) nanofibers with high tensile strength are known to be an effective choice for enhancement of the mechanical properties of WSR. [21][22][23][24] It seems that the hydrophobic properties of rubber matrix and SBS nanofibers lead to miscibility of the constituents of appropriate composites and result in better stress distribution.…”

Simulation of Degraded Properties of 2D plain Woven C/SiC Composites under Preloading Oxidation Atmosphere

“…Illustration of the periodic boundary conditions on the unit cell model[26] Calculate the initial elastic parameters of unidirectional C/SiC compositeCalculate the residual elastic moduli and shear moduli of the composite in the other two directions (y, z) Calculate the residual elastic moduli and shear moduli of the composite in the other two directions (y, z) Put the residual elastic parameters into the unit cell model as the basic attributes of yarn Put the residual elastic parameters into the unit cell model as the basic attributes of yarn Impose periodic boundary conditions Impose periodic boundary conditions Get the residual axial elastic modulus of oxidized 2D C/SiC composites Get the residual axial elastic modulus of oxidized 2D C/SiC composites Calculate the residual axial elastic modulus of unidirectional C/SiC composite Create the unit cell model of 2D CThe analysis strategy of residual axial modulus of 2D plain woven C/SiC composite Appl Compos Mater…”