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Title: Effect of Geometry and Orientation on the Tensile Properties and Failure Mechanisms of Compliant Suture Joints
Compliant sutures surrounded by stiff matrices are present in biological armors and carapaces, providing enhanced mechanical performance. Understanding the mechanisms through which these sutured composites achieve outstanding properties is key to developing engineering materials with improved strength and toughness. This article studies the impact of suture geometry and load direction on the performance of suture joints using a two-stage reactive polymer resin that enables facile photopatterning of mechanical heterogeneity within a single polymer network. Compliant sinusoidal sutures with varying geometries are photopatterned into stiff matrices, generating a modulus contrast of two orders of magnitude. Empirical relationships are developed connecting suture wavelength and amplitude to composite performance under parallel and perpendicular loading conditions. Results indicate that a greater suture interdigitation broadly improves composite performance when loading is applied perpendicular to suture joints, but has deleterious effects when loading is applied parallel to the joint. Investigations into the failure mechanisms under perpendicular loading highlight the interplay between suture geometry and crack growth stability after damage initiation occurs. Our findings could enable a framework for engineering composites and bio-inspired structures in the future.  more » « less
Award ID(s):
2038505
PAR ID:
10467185
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
American Chemical Society
Date Published:
Journal Name:
ACS Applied Materials & Interfaces
Volume:
15
Issue:
8
ISSN:
1944-8244
Page Range / eLocation ID:
11084 to 11091
Subject(s) / Keyword(s):
compliant interlayers, suture joints, geometric interlayer, mechanics of composites, crack growth stability, photopolymers.
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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