Keywords
Additive manufacturing; Machine learning; Process-structure-property relationships
Abstract
Additive manufacturing (AM) has been increasingly used in the automotive, aerospace, defense, medical devices, and energy sectors, due to its ability to fabricate parts with complex geometries and excellent mechanical behavior. However, it is challenging to design for AM and optimize process parameters because the process-structure-property (PSP) relationships in AM are complex. This study investigates the PSP relationships in AM through experimentation and machine learning. First, the effect of process parameters on the flexural behavior of soft-hard sandwich beams fabricated by multi-material AM is investigated. How the flexural modulus, flexural strength, and failure mechanisms of the soft-hard sandwich beams relate to process parameters such as nozzle temperatures and print speeds for soft and hard materials is revealed. Second, a novel multi-process AM system is developed to fabricate thermoplastics and thermosets in a single print. The interfacial behavior between thermoplastics and thermosets, including their in-situ surface morphology, bonding strength, and failure mechanisms, is studied. Third, machine learning and feature representation approaches are developed to predict the stress-strain relationships of additively manufactured metamaterials with varying structure and process parameters. Two novel feature representations are developed to transform process and structure parameters from tabular format into images. Fourth, a transfer learning framework is introduced to predict the stress-strain relationships of additively manufactured metamaterials in the target domain with a small dataset by leveraging prior knowledge in the source domain.
Completion Date
2024
Semester
Summer
Committee Chair
Wu, Dazhong
Degree
Doctor of Philosophy (Ph.D.)
College
College of Engineering and Computer Science
Department
Department of Mechanical and Aerospace Engineering
Degree Program
Mechanical Engineering
Format
application/pdf
Identifier
DP0028874
URL
https://stars.library.ucf.edu/cgi/viewcontent.cgi?article=1390&context=etd2023
Language
English
Rights
In copyright
Release Date
2-15-2028
Length of Campus-only Access
3 years
Access Status
Doctoral Dissertation (Campus-only Access)
Campus Location
Orlando (Main) Campus
STARS Citation
Liu, Qingyang, "Understanding Process-Structure-Property Relationships in Additive Manufacturing via Experimentation and Machine Learning" (2024). Graduate Thesis and Dissertation 2023-2024. 488.
https://stars.library.ucf.edu/etd2023/488
Accessibility Status
Meets minimum standards for ETDs/HUTs
Restricted to the UCF community until 2-15-2028; it will then be open access.