자료유형  

 학위논문

Control Number  

0017164497

International Standard Book Number  

9798384044635

Dewey Decimal Classification Number  

547

Main Entry-Personal Name  

Khan, Abdul Sayeed.

Publication, Distribution, etc. (Imprint  

[S.l.] : University of Michigan., 2024

Publication, Distribution, etc. (Imprint  

Ann Arbor : ProQuest Dissertations & Theses, 2024

Physical Description  

200 p.

General Note  

Source: Dissertations Abstracts International, Volume: 86-03, Section: A.

General Note  

Advisor: Dong, Pingsha.

Dissertation Note  

Thesis (Ph.D.)--University of Michigan, 2024.

Summary, Etc.  

요약Multi-material lightweight structures by "using the right material at the right place" have become increasingly important for ensuring environmental sustainability. Conventional mechanical fastening and/or adhesive bonding processes can be inefficient, unreliable, and time-consuming, therefore unable to take full advantage of multi-material structures and emerging advanced manufacturing processes, such as additive manufacturing (AM). Due to material incompatibility between some of the dissimilar material combinations, e.g., between aluminum alloy and steel or between polymer composite and metal, there have been major challenges in achieving direct welding or joining. For instance, fusion-based dissimilar metal joining or AM, e.g., between aluminum alloy and steel, introduces brittle intermetallic compounds (IMCs) between the aluminum-steel interface, which can cause severe cracking and galvanic corrosion or stress corrosion cracking. However, there have been some promising developments over the recent years. Some solid-state dissimilar material joining and AM processes, e.g., friction-based processes for producing direct bonding between dissimilar metals, e.g., between aluminum alloy and steel and between polar polymer (PA66) and aluminum, and friction-based solid-state additive manufacturing (additive friction stir deposition or AFSD). However, the direct joining between non-polar polymer (such as polypropylene or PP) and metal and suppression of IMCs for improving corrosion resistance in bimetallic joints is still not achieved. The solid-state additive manufacturing method available to date (e.g., AFSD) imparts severe compression force and overheats the substrate, making the process challenging for relatively thin substrates and safety-critical applications.In this research, solid-state friction-based dissimilar material direct joining and additive manufacturing methods are investigated. Using the friction-based solid-state method, it first achieved a novel metal to hard-to-weld polypropylene (PP) composite direct joining using a functionally active interface modulator insert layer under localized temperature and pressure conditions. Utilizing carbon-oxygen-aluminum (C-O-Al) type covalent bonding between aluminum alloy and polypropylene composite, it eliminated fasteners and adhesives for a robust joint stronger than the base composite material. Subsequently, it utilized previously discovered, nanoscale shear localization-induced amorphization (NSLIAA) to join thin gauge aluminum to steel materials directly under controlled friction spot joining configuration for the suppression of IMCs and increased corrosion resistance.It has then demonstrated a novel friction-based solid-state metal additive manufacturing method to enable melt-less dissimilar material additive manufacturing of metals and alloys directly at a large scale without solidification defects and minimal substrate compression force-induced instabilities. It was termed SoftTouch AMTM due to its low temperature and low compression force features and defined as an additive friction extrusion deposition (AFED) process due to its friction-based extrusion and additive processing features. SoftTouch AMTM utilizes super-plasticity to soften the feedstock in two steps, eliminating the need for direct contact between substrate and feedstock and providing grain refinement and severe cold working (severe plastic deformation) below the melting temperatures of metallic materials. It avoids using pricy powders and is fully capable of utilizing off-the-shelf metallic bars as feedstock. It has proven crucial for future demands of large-area additive manufacturing, energy sectors, and sustainability.With the above accomplishments, the following describes the major intellectual merits and broad engineering impacts of this research:• It proposed a new carbon-oxygen-metal or C-O-M type covalent bond formation mechanism between non-polar polypropylene composite and metals through an intermediary functional layer.• Discovered a mechanistic description that if the amorphous phase is present at the Al/Steel joining interface, then the electrolytic ions from the corrosive media are not able to penetrate the amorphous phase, which occurs through the grain boundaries in crystalline intermetallic compounds.• Developed novel SoftTouch AMTM process concepts and laboratory implementation for consistent solid-state deposition of aluminum to aluminum, aluminum to stainless steel, carbon steel to carbon steel, and stainless steel to carbon steel, which potentially offers rapid large-area solid-state additive manufacturing of similar and dissimilar material systems.• Introduced a novel modular multi-material insert die design and rotational stability requirements in the SoftTouch AMTM system for achieving consistent solid-state deposition of aluminum to aluminum, aluminum to stainless steel, and stainless steel to carbon steel.The dissimilar material direct joining discovered during this research provides process development platforms for automotive lightweighting. It is intended to support the Department of Energy's (DOE) multi-material lightweight vehicle (MMLV) initiatives in the coming years. It will further enable using metal to hard-to-weld polymer dissimilar and aluminum to steel-type bi-metallic pairs in severe and harsh environmental conditions without significantly losing structural strength. The research work was supported by the National Science Foundation (NSF - CMMI - 2126163) and the Electric Power Research Institute (EPRI) and is intended for multi-material structural lightweighting and rapid, defect-free, large-area solid-state additive manufacturing for diverse industrial applications, including light water reactor (LWR) and energy sectors for sustainability.

Subject Added Entry-Topical Term  

Polymer chemistry.

Subject Added Entry-Topical Term  

Materials science.

Subject Added Entry-Topical Term  

Mechanical engineering.

Subject Added Entry-Topical Term  

Industrial engineering.

Subject Added Entry-Topical Term  

Sustainability.

Index Term-Uncontrolled  

Structural lightweighting

Index Term-Uncontrolled  

Additive manufacturing

Index Term-Uncontrolled  

Automotive corrosion

Index Term-Uncontrolled  

Intermetallic compounds

Index Term-Uncontrolled  

Brittle intermetallic compounds

Added Entry-Corporate Name  

University of Michigan Naval Architecture & Marine Engineering

Host Item Entry  

Dissertations Abstracts International. 86-03A.

Electronic Location and Access  

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Control Number  

joongbu:656747