Abstract
The purpose of the current study is to provide a monitoring scheme for evaluating the reliability of drilling of electronic circuit board (ECB) made of FR4 composite materials. The ECB is a laminated mechanical structure. Delamination often occurs at the hole exit during drilling. The resulted delamination deteriorates the long-term performance of the ECB when subject to mechanical and/or thermal loading. Acoustic emission can monitor the extent of this damage. A linear relationship exists between the size of delamination and the energy level of emitted signal when the proposed signal processing technique is used. The results contribute to higher quality ECB's and can be applied in the manufacturing stage in an automated manner.