09 Composite Materials Free Online FlashCards

What defines a composite material?

A material made from two or more distinct constituents that remain identifiable within it.

What does the matrix do in a composite?

It binds and supports the reinforcement, transfers load between it and neighboring regions, and helps protect it from damage and the environment.

What is the main role of reinforcement?

It supplies much of the composite’s strength and stiffness, especially along the reinforcement’s own direction.

What is the interface in a composite?

It is the boundary where reinforcement and matrix meet. Effective bonding and compatibility help transfer load between them.

What are three common engineered composite classes?

Polymer-matrix composites (PMCs), metal-matrix composites (MMCs), and ceramic-matrix composites (CMCs).

What is characteristic of unidirectional fibers?

Fibers run mainly in one direction, giving high performance along that direction but less reinforcement across it.

What can woven or multidirectional fabrics provide?

Fibers cross in two or more directions, which can provide strength in multiple directions and help the material conform to shapes.

How can a laminate’s ply arrangement affect its behavior?

A laminate stacks plies with selected fiber directions. The order and angles of those plies affect the finished part’s behavior.

What is a trade-off of chopped-fiber or particle composites?

They can be formed into complex shapes, but typically provide less directional reinforcement than continuous, aligned fibers.

How does a sandwich structure achieve high bending stiffness at low weight?

Thin, strong face sheets are separated by a lightweight core, providing high bending stiffness at low weight.

What does it mean for a fiber composite to be anisotropic?

Anisotropic materials have properties that vary with direction. A unidirectional composite is generally stiffer along its fibers than across them.

What is delamination, and why can it be a concern?

Delamination is damage between layers. It can be difficult to detect.