Sandvik Coromant Machining carbon fibre materials - Manual (Page 23)

Quality issues in CFRP
Quality is not easily assessed: •
- there is no chip to look at
- roughness measurement is not significant
- damage can be not visible (delamination)
The main indicator is the hole quality •
(and tool conditions)
Delamination •
- Separation of the bottom layer(s) due to the “thrust” of the drill
Splintering •
- Residual fibres in the interior of the hole, due to poor cutting action
Delamination
Splintering/fraying
Tool wear on cutting edge
SANDVIK COROMANT USER’S GUIDE - COMPOSITE SOLUTIONS 23