Publication Date
2018
Document Type
Thesis
Committee Members
Joy Gockel, Ph.D. (Advisor); Onome Scott-Emuakpor, Ph.D. (Committee Member); Craig Baudendistel, Ph.D. (Committee Member)
Degree Name
Master of Science in Mechanical Engineering (MSME)
Abstract
Metal additive manufacturing (AM) is a method to create complex components in a layer-by-layer process. Currently, there is a lack of understanding in the processing-structure-properties-performance relationship, particularly related to defects inherent to the AM process. This work investigates the relationship of process parameters, as-built surface roughness, and mechanical performance for nickel-based superalloy 718 built using laser powder bed fusion. The surface roughness of components built using varied processing parameters was characterized using both nondestructive and destructive measurement techniques. Finite element analysis was used to study the stress concentration on surface profiles. Statistical correlations are presented between contour processing parameters and surface roughness metrics. Results show that destructive measurements are required to expose obstructed features and highly concentrated stress is present on crack-like surface features. The discovered understanding of the surface roughness behavior can be used for further process optimization and to inform the certification and qualification strategy for AM components.
Page Count
122
Department or Program
Department of Mechanical and Materials Engineering
Year Degree Awarded
2018
Copyright
Copyright 2018, all rights reserved. My ETD will be available under the "Fair Use" terms of copyright law.
