POLYMER MATRIX
COMPOSITES
,Why combine materials?
Competing requirements
A component may need low mass, stiffness,
impact resistance, and ease of manufacturing. A
single polymer does not always meet this
combination of requirements.
Integrated architecture
In composites, performance depends on the
constituents and how they are arranged.
Reinforcement type, orientation, interface, and
defects must be considered together.
Engineering decision
The appropriate solution is the one that meets the
application, process, and service-life requirements,
not the one with the highest value of an isolated
property. Sandwich panel with reinforced faces and a cellular core; not to scale.
,Matrix, reinforcement, and interphase
Continuous matrix
The polymer surrounds the other constituents,
gives the component its shape, and participates in
stress transfer. Its thermal and chemical response
constrains the service environment.
Dispersed phase
Fibers or particles modify mechanical and
functional properties. Their effectiveness as
reinforcement depends on geometry, content,
dispersion, and interaction with the matrix.
Interaction region
The interphase may have a composition or
molecular mobility different from the polymer
farther from the reinforcement. Voids are defects,
not an additional reinforcement. Light-blue matrix, dark fibers, and a gold interphase; thicknesses are
illustrative.
, Scales of organization
A local change can alter component performance, but the relationship among scales must be demonstrated.
Scale What is observed Engineering question
How does the matrix respond to heat and
Molecular Chains, bonds, and crosslinking
time?
How is load transferred between
Microscopic Fibers, particles, interphase, and voids
constituents?
How does the architecture distribute
Mesoscopic Plies, fabrics, and resin-rich regions
stresses?
Component, joints, and boundary Where do deformation, damage, and
Structural
conditions failure occur?
Characterizing only one scale does not automatically describe the entire component.
COMPOSITES
,Why combine materials?
Competing requirements
A component may need low mass, stiffness,
impact resistance, and ease of manufacturing. A
single polymer does not always meet this
combination of requirements.
Integrated architecture
In composites, performance depends on the
constituents and how they are arranged.
Reinforcement type, orientation, interface, and
defects must be considered together.
Engineering decision
The appropriate solution is the one that meets the
application, process, and service-life requirements,
not the one with the highest value of an isolated
property. Sandwich panel with reinforced faces and a cellular core; not to scale.
,Matrix, reinforcement, and interphase
Continuous matrix
The polymer surrounds the other constituents,
gives the component its shape, and participates in
stress transfer. Its thermal and chemical response
constrains the service environment.
Dispersed phase
Fibers or particles modify mechanical and
functional properties. Their effectiveness as
reinforcement depends on geometry, content,
dispersion, and interaction with the matrix.
Interaction region
The interphase may have a composition or
molecular mobility different from the polymer
farther from the reinforcement. Voids are defects,
not an additional reinforcement. Light-blue matrix, dark fibers, and a gold interphase; thicknesses are
illustrative.
, Scales of organization
A local change can alter component performance, but the relationship among scales must be demonstrated.
Scale What is observed Engineering question
How does the matrix respond to heat and
Molecular Chains, bonds, and crosslinking
time?
How is load transferred between
Microscopic Fibers, particles, interphase, and voids
constituents?
How does the architecture distribute
Mesoscopic Plies, fabrics, and resin-rich regions
stresses?
Component, joints, and boundary Where do deformation, damage, and
Structural
conditions failure occur?
Characterizing only one scale does not automatically describe the entire component.
