Coefficient of Thermal Expansion for Composites with Randomly Oriented Fibers

Craft, William J.; Christensen, Richard M.

doi:10.1177/002199838101500102

Cited by 68 publications

(13 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…When passing the T g , the mobility of the epoxy network is greatly increased and thus dimension changes can occur more freely as the epoxy can adopt different configurations around the epoxy-steel interface. The measured CTE value for the neat CSM glass/epoxy agrees well with data of a randomly oriented glass/polyester composite, with a CTE of 16.7 μm/(m°C) [34].…”

Section: Heating and Coolingsupporting

confidence: 80%

In-situ Curing Strain Monitoring of a Flat Plate Residual Stress Specimen Using a Chopped Stand Mat Glass/Epoxy Composite as Test Material

et al. 2015

View full text Add to dashboard Cite

The curing stresses in a newly proposed bi-axial residual stress testing configuration are studied using a chopped strand mat glass/epoxy specimen. In-situ monitoring of the curing is conducted using dielectric and fibre Bragg grating sensors. It is confirmed that a bi-axial residual stress state can be introduced in the specimens during curing and a quantification of its magnitude is presented. An alternative decomposition method used for converting the dielectric signal into a material state variable is proposed and good agreement with models found in the literature is obtained. From the cure cycles chosen it is suggested that any stress build up in the un-vitrified state is relaxed immediately and only stress build up in the vitrified state contributes to the residual stress state in the specimen.

show abstract

Section: Heating and Coolingsupporting

confidence: 80%

In-situ Curing Strain Monitoring of a Flat Plate Residual Stress Specimen Using a Chopped Stand Mat Glass/Epoxy Composite as Test Material

et al. 2015

View full text Add to dashboard Cite

show abstract

“…In electronic packaging applications, the thermal expansion coefficient of composites becomes a critical property parameter which many researches have focused on (Kim et al, 2001;Vaidya and Chawla, 1994;Arpon et al, 2003;Zhang et al, 2003;Bowles and Tompkins, 1989;Craft and Christensen, 1981), researching results showed that the addition of SiC particles in Al matrix could decrease the CTE of Al matrix, and Al/SiC p composite could be one kind of suitable and versatile material for electronic packaging (Arpon et al, 2003;Zhang et al, 2003).…”

Section: Introductionmentioning

confidence: 99%

Effect of thermal cycling on the expansion behavior of Al/SiCp composite

Chen

Zhang

et al. 2009

Journal of Materials Processing Technology

View full text Add to dashboard Cite

“…The reinforcement phase (f) is assumed to remain elastic, while the matrix phase (m) may become elasticplastic when a given yield condition has been satisfied. In the plastic region, the matrix constitutive relation is described by (2), with Mm and Lm replaced by instantaneous compliance and stiffness. Again, Mm and Lm are assumed to be piecewise linear, symmetric, and satisfy the requirement of plastic incompressibility of the matrix.…”

Section: Elastic-plastic Composites (I) Fibrous-compositesmentioning

confidence: 99%

Thermal Expansion of Elastic-Plastic Composite Materials

Dvorak

1986

Journal of Applied Mechanics

View full text Add to dashboard Cite

Exact relationships are derived between instantaneous overall thermal stress or strain vectors and instantaneous overall mechanical stiffness or compliance, for two binary composite systems in which one of the phases may deform plastically. Also, the local instantaneous thermal strain and stress concentration factors are related in an exact and on local fields in the two composite materials..'-'.''. '".'' . ' . ".'", . € " caused in a prestressed fibrous composite by a small uniform thermal -change can be related in an exact way to thermoelastic constants of the phases and to instantaneous overall compliance. No restrictions need to be imposed on the type of prestress or on the matrix constitutive law except for plastic incompressibility, but the fiber must be isotropic or transversely isotropic and remain elastic. This result has been applied in analysis of a composite cylinder element (DVORAK and WUNG 1984) subjected to axisymmetric mechanical loading, uniform thermal changes, and variations in matrix yield stress.The present paper develops the connections between overall instank,22taneous mechanical and thermal properties in a more general way. First, it is shown that the overall thermal stress and strain vectors for an 1, ELASTIC FIBROUS COMPOSITEA binary composite material consists of a matrix reinforced by aligned and bonded cylindrical fibers. Both phases are assumed to be homogeneous and transversely isotropic about the fiber direction x 3 . In the transverse x 1 x 2 -plane, the cross sections and distribution of the phases can be arbitrary providing that the composite is statistically homogeneous, transversely isotropic, and free of voids.A representative volume element V of the composite is selected and subjected to a certain loading or deformation history which is imposed through application of uniform overall stresses To or strains To to the surface S of volume V. Also, a certain uniform thermal change has been applied such that the current temperature in V is constant and equal to 0o . At this particular point of the loading sequence simultaneous increments of d and de, or d -and de, are applied to V.The response of the composite to these load increments is described by constitutive equations:where M,L are (6x6) overall stiffness and compliance matrices, and m,t are (6x) overall thermal strain and stress vectors*.While M and L are known, we wish to determine the vectors m and 1.To this end it is necessary to specify the constitutive equations for field averages of the phases: which are analogous to (1); f,m indicate the "fiber" and "matrix"phases. In elastic composites, these phases are interchangeable and f,m are used merely for convenience of notation.Since both the composite and each of the phases are transversely isotropic about x 3 , it is possible to write a subset of (1) and (2) which relates the first two stress and strain invariants. With top bars and subscripts r,f,m omitted in (1) and (2) In the second step of the procedure, the tractions 1 and dr must All strain and stress increm...

show abstract

Coefficient of Thermal Expansion for Composites with Randomly Oriented Fibers

Cited by 68 publications

References 4 publications

In-situ Curing Strain Monitoring of a Flat Plate Residual Stress Specimen Using a Chopped Stand Mat Glass/Epoxy Composite as Test Material

In-situ Curing Strain Monitoring of a Flat Plate Residual Stress Specimen Using a Chopped Stand Mat Glass/Epoxy Composite as Test Material

Effect of thermal cycling on the expansion behavior of Al/SiCp composite

Thermal Expansion of Elastic-Plastic Composite Materials

Contact Info

Product

Resources

About