Effects of 90°ply thickness on the transverse crack behavior in CF/BMI cross-ply laminates

摘要

Microscopic damage initiation and growth behavior in high temperature bismaleimide-based CFRP laminates under fatigue loading were observed. Three types of cross-ply laminate, [0/90_2/0], [0_2/90_3/0_2] and [0_2/90_4/0_2], were tested to discuss the effect of ply thickness. Damage observation was conducted by using optical microscopy for edge damages and soft X-ray radiography for internal damages. Variational approach was used to derive the energy release rate associated with matrix cracking Matrix cracking behavior was modeled using modified Paris-law approach.