Tensile response of additively manufactured carbon/nylon joints using optical fibers and digital image correlation

ABSTRACT

Additive manufacturing (AM) has gained popularity due to reduced production times of low-cost and geometrically complex structures. Due to technological constraints such as print volume, time, and thermal stability of large AM parts, adhesive joints are commonly used in assembling smaller components in large-scale polymeric structures. This work investigates the feasibility of using embedded optical fibers to monitor strain distributions within AM composite (carbon fiber/nylon) single-lap shear (SLS) joints. Internal strain distributions within the adhesive and surface strain fields of the SLS joints with AM adherends under tensile loads were obtained using optical fibers and digital image correlation, respectively. Results indicate negligible influence of optical fibers on the failure strength and axial stiffness of 3D-printed SLS joints under quasi-static loading. Higher strains were observed at the bond edges within the adhesive (using optical fiber) and the surface (using DIC) of the joints due to the rotation of the bond under loading. All specimens failed in the adherends beyond the bonded region due to their low interlaminar strength.

KEYWORDS:

• Additive manufacturing
• Lap-shear joints
• optical fibers
• digital image correlation
• internal strain

Acknowledgments

The authors gratefully acknowledge the support from the Department of Aerospace Engineering and the High-Performance Advanced Composites Laboratory at Mississippi State University for additive manufacturing and testing.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Author contributions

Conceptualization, R.W.S. and S.S.; Methodology, R.W.S. and S.S.; Validation, S.S. and A.K.S.; Formal analysis, S.S., A.K.S., M.D., J.K., L.P.; Investigation, S.S., A.K.S., M.D., J.K., L.P.; Resources, R.W.S.; Data Curation, S.S.; Writing – original draft preparation, S.S. and A.K.S.; Writing – review and editing, R.W.S. and S.S.; Supervision, R.W.S. and S.S.; Project administration, R.W.S.; Funding acquisition, R.W.S. All authors have read and agreed to the published version of the manuscript.

Data availability statement

The datasets generated during and/or analyzed during the current study are available on reasonable request.

Additional information

Funding

The study was supported by a grant from the Mississippi Space Grant Consortium [Award #: 22-08-09].