SYMPOSIA PAPER Published: 22 September 2020
STP163120190127

Effects of Surface Roughness and Porosity on Fatigue Behavior of AlSi10Mg Produced by Laser Powder Bed Fusion Process

Source

Effects of as-built surface roughness and porosity on fatigue performance were investigated for AlSi10Mg produced by the laser powder bed fusion (L-PBF) process. As-built (with original surface roughness) and polished (surface roughness removed) samples were used to study the effect of surface roughness on fatigue strength. Results indicate that roughness has a significant effect on fatigue strength (approximately 40% decrease), and the current empirical model used for conventional materials significantly underestimates the roughness effect. The fatigue strengths in border and hatch regions were studied using polished samples and machined and polished samples. The machined and polished samples show a phenomenal fatigue strength of 154 MPa, which is 50% more compared to the polished-only samples (96 MPa). The samples were then subjected to homogenization to remove residual stress and ensure identical microstructure. The homogenized samples show no difference in fatigue strength in the border and hatch regions. The results suggest that residual stress might play a role in decreasing fatigue strength in the border region. Different porosity levels were produced to study the effect of defects on fatigue strength. The results show that the modified Murakami's model can correctly predict the fatigue strength based on defect size.

Author Information

Lai, Wei-Jen
Ford Motor Co., Dearborn, MI, US
Li, Ziang
Ford Motor Co., Dearborn, MI, US
Ojha, Avinesh
Ford Motor Co., Dearborn, MI, US
Li, Yang
Ford Motor Co., Dearborn, MI, US
Forsmark, Joy
Ford Motor Co., Dearborn, MI, US
Engler, Carlos
Ford Motor Co., Dearborn, MI, US
Su, Xuming
Ford Motor Co., Dearborn, MI, US
Price: $25.00
Contact Sales
Related
Reprints and Permissions
Reprints and copyright permissions can be requested through the
Copyright Clearance Center
Details
Pages: 229–246
DOI: 10.1520/STP163120190127
ISBN-EB: 978-0-8031-7709-3
ISBN-13: 978-0-8031-7708-6