The notched strength of angle ply laminates

摘要

Short, wide samples of angle ply laminates have been notched and their strengths measured as a function of notch depth. They were very strong and very notch resistant for ply angles of 15° and 30°. Thus, for example [±15]{sub}s carbon-epoxy samples had K{sub}(Ic) values of about 86±11 MPa m{sup}(1/2), with glass-epoxy about the same. In contrast, a [0,+45,90,-45]{sub}s carbon-epoxy laminate had a K{sub}(Ic) of only about 22.5±0.5 MPa m{sup}(1/2). The corresponding works of fracture were about 0.52 MJm{sup}(-2) for cabon-epoxy, 0.74 MJm{sup}(-2) for glass-epoxy ply laminates suggests that there may be some untapped potential for aerospace use.