Discontinuous Fibres

Question 1

Name three advantages of discontinuous fibres:

Answer 1

More design freedom (fibre length, orientation, type).

Better manufacturability - improved drape-ability, flow-ability, easier to automate (high production volume and low cycle time).

Better lifecycle - easier to recycle and repair.

Question 2

Name three disadvantages of discontinuous fibres:

Answer 2

Difficult to achieve effective stress transfer from matrix to fibre.

Challenging to achieve high fibre volume fraction.

Difficult to model analytically for design purposes.

Question 3

Name two manufacturing methods for discontinuous fibres:

Answer 3

Injection moulding.
Sheet compression moulding.

Question 4

What are the two failure modes for discontinuous fibres?

Answer 4

Fibre pull-out
Fibre fracture

Question 5

What is the criteria for pull-out or fracture?

Answer 5

PO: When fibre length is less than critical fibre length.
FF: When fibre length is more than critical fibre length.