In this study, carbon/epoxy composite DCB(double cantilever beam) specimens based on K-means clustering and wavelet transform analyses are presented. For the fracture Mode I, the fiber orientation θ = [0 ]24 and θ = [±45]12 both shown up stable crack growth in DCB testing. For the fiber orientation θ = [0 ]24 , the continuous type AE signal showed at central frequency 130～270kHz, which means that matrix micro cracking was occurred. The Burst type AE signal was occurred at central frequency 200～300kHz due to fiber bridging and fiber breaking. Other burst type AE signals were occurred at central frequency 130～180kHz with very high amplitude due to fiber bridging. For the fiber orientation θ = [±45]12 , the burst type signal showed at central frequency 220～300kHz, which means that fiber breaking was occurred. Mixed type of burst and continuous signals were captured at central frequency 250～480kHz due to fiber friction.

Abstract
 1. 서론
 2. DCB 층간파괴시험과 섬유브리징
 3. 실험재료 및 실험방법
  3.1 실험재료 및 시험편
  3.2 실험방법
 4. 실험결과 및 고찰
 5. 결론
 후기
 참고문헌

• 이장규(인천대학교 기계시스템공학부) | Zhang-Kyu Rhee
• 우창기(인천대학교 기계시스템공학부) | Chang-Ki Woo 교신저자