Composite Laminate Design for Improved Open-Hole Compression Strength using Non-Standard Ply Angles and Customized Stacking Sequences Characterized by [D] Matrix

• Published in: Materials today communications Vol. 24; p. 101172
• Main Authors: Su, Yu, Batra, Gaurav, Colton, Jonathan S.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.09.2020
• Subjects: misaligned loading; Non-standard angle; open-hole compression; stacking sequence; stacking sequence; misaligned loading; open-hole compression; Non-standard angle
• ISSN: 2352-4928; 2352-4928
• DOI: 10.1016/j.mtcomm.2020.101172

•Non-standard ply angle designs at matched in-plane stiffness can reduce laminate thickness.•Non-standard ply angle designs at matched in-plane stiffness can improve open-hole compression strength when subject to a small load misalignment.•Customized stacking sequences by placing higher-angle plies on the surface can improve open-hole compression strength of both standard and non-standard angle designs.•The improvement from customized stacking sequence linearly decreases with the lower ply angle and can be predicted from the [D] matrix. The conventional design of composite laminates underutilizes the large design space available due to stacking sequences and ply angles. This paper studies the use of non-standard ply angles and customized stacking sequences by placing higher-angle plies on the surface for reduced ply thickness and increased open-hole compression strength. Tests show non-standard angle designs at matched in-plane stiffness improve failure strength as compared to standard angle wing-skin laminates when subject to a small load misalignment. Customized stacking sequences improve the strength of both standard and non-standard angle designs, the improvement of which linearly decreases by having the lower ply angle on the surface. The results match predictions derived from the [D] matrix.