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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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Effects of High Temperature on Torsional Fatigue Performance of Additively Manufactured Inconel 718 of Vertical Build Orientation
The additive manufacturing process has allowed for advancement in the rapid development of aircraft gas turbine engine components, due to its rapid prototyping capabilities with the added benefits of geometric design flexibility, and reduced production cost. These turbine engine components often experience a multiaxial stress state at high temperature, in which an understanding of the axial and torsional response exhibited by these additively manufactured materials is of import. The present study is novel in that it assesses the torsional fatigue performance of additively manufactured machined and heat-treated Inconel 718, a metal superalloy commonly used in gas turbine engines, of vertical (Z) build orientation, at an elevated temperature of 650°C. Preliminary findings exhibit a reduction in shear moduli and plastic shear strain absorbing capacity at 650°C compared to room temperature. Also evident was cyclic softening from the first to the stabilized cycle and an approximate torsional fatigue life on the order of 10^3 cycles when cycling at an angle of twist range of Δφ = ±15°.
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- Award ID(s):
- 2055027
- PAR ID:
- 10561222
- Publisher / Repository:
- American Institute of Aeronautics and Astronautics
- Date Published:
- ISBN:
- 978-1-62410-711-5
- Format(s):
- Medium: X
- Location:
- Orlando, FL
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.2514/6.2024-1795
