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Abstract This study uses the Taguchi optimization methodology to optimize the fatigue performance of short carbon fiber-reinforced polyamide samples printed via fused deposition modeling (FDM). The optimal printing properties that maximize the fatigue limit were determined to be 0.075 mm layer thickness, 0.4 mm infill line distance, 50 mm/s printing speed, and 55 °C chamber temperature with layer thickness being the most critical parameter. To qualify fatigue endurance limit, the energy dissipation in uniaxial fatigue was quantified by using hysteresis energy and temperature rise at steady state. From these results, the fatigue limit for a specimen printed with optimized printing parameters was predicted to be 69 and 70 MPa from hysteresis energy and temperature rise at steady state methods, consecutively, and it was experimentally determined to be 67 MPa. This work demonstrates the effectiveness of the Taguchi optimization method when applied to additive manufacturing and the swift ability to predict the fatigue limit of a material with only one specimen to produce optimal additively manufactured components for industrial applications, as validated by experimental fatigue testing.
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Rapid evaluation of fatigue limit using energy dissipation
Abstract Four different experimental approaches for rapid estimation of fatigue limit (endurance limit) based on energy dissipation during cyclic loading are discussed. The presented approaches use energy dissipation and thermography and can reliably evaluate the fatigue limit of material by conducting the fatigue test on a single specimen. Results show that the released energy due to damage accumulation at the stress levels above the fatigue limit changes the trend of energy dissipation and that this trend can be used to predict the fatigue limit. Experimental results on CS 1018 and SS 304 specimens are presented to illustrate the utility of the proposed methods.
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- Award ID(s):
- 2052810
- PAR ID:
- 10401855
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Fatigue & Fracture of Engineering Materials & Structures
- Volume:
- 46
- Issue:
- 6
- ISSN:
- 8756-758X
- Page Range / eLocation ID:
- p. 2156-2167
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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