Comparison of Additively Manufactured and Wrought 17-4 PH Stainless Steels in Ultra Low Cycle Fatigue

<p>Additive manufacturing (AM) processes allow for creation of complex geometries that are otherwise impractical to fabricate with traditional subtractive methods. AM technology has potential to improve the optimization of seismic lateral force resisting components which dissipate seismic energy through large plastic strains; however, the ultra low-cycle fatigue performance of AM metals are not yet well understood. Void formation during the AM fabrication process has potential to affect performance. This study compares the performance of heat-treated and non-heat-treated AM and wrought 17-4PH stainless steel in Ultra Low Cycle Fatigue. To understand ULCF performance differences between the AM and wrought specimens, post fracture microstructure, fractography, surface hardness, and material characterizations are conducted. Results indicate reduced fatigue life for AM 17-4PH stainless steel as compared to the wrought counterparts. Fatigue life reductions of 62% and 65% were measured for the AM steel materials (as compared to the wrought counterparts) at 3% and 4% applied strain amplitude respectively. Applied material heat treatments had no observable effect on ULCF performance. </p>

Name thesis:degree_name

Master of Science in Civil Engineering (MSCE)

Level thesis:degree_level

Thesis

Year dc:date.available

2020

Author dc:creator

• Strasser, Timothy

Advisor dc:contributor.advisor

• Prinz, Gary S.

Contributors dc:contributor

• Murray, Cameron D.
• Hale, W. Micah

• 17-4 PH Stainless Steel
• 3D-Printing
• Additive Manufacturing
• Material Characterization
• Tensile Testing
• Ultra Low Cycle Fatigue
• Civil Engineering
• Mechanics of Materials
• Structural Engineering

Repository record dc:identifier

https://scholarworks.uark.edu/etd/3877

OAI identifier oai:identifier

oai:scholarworks.uark.edu:etd-5427