Laser Powder Bed Fusion Additive Manufacturing of Copper Wicking Structures for Heat Pipes and Vapor Chambers
Open Access
- Author:
- Mezghani, Adnen
- Graduate Program:
- Additive Manufacturing and Design
- Degree:
- Master of Science
- Document Type:
- Master Thesis
- Date of Defense:
- February 28, 2020
- Committee Members:
- Abdalla Ramadan Nassar, Thesis Advisor/Co-Advisor
Edward William Reutzel, Committee Member
Judith Todd Copley, Committee Member
Timothy W. Simpson, Program Head/Chair - Keywords:
- vapor chamber
porous structure
wick
additive manufacturing
copper
Thermal management
vapor chamber
porous structure
wick
additive manufacturing; copper; Thermal management
Vapor chamber
porous structure
wick
additive manufacturing
copper
thermal management - Abstract:
- An integral component in two-phase thermal management systems, namely, heat pipes (HP) and vapor chambers (VC), is a porous wicking structure. Traditional methods for manufacturing wicking structures within HPs and VCs involve secondary manufacturing and assembly processes and are generally limited to simple pipe-like or plate-like geometries. More complex geometries may, however, be possible with laser powder bed fusion (LPBF) additive manufacturing (AM), which permits high level of geometric complexity, part consolidation, and customization. The work presented in this thesis aims to leverage the unprecedented level of customization and geometric complexity permitted through LPBF AM to produce copper HPs and VCs with integrated wicking structures. Several copper wicking structures were successfully fabricated via partial sintering and via the formation of square, hexagonal, and rectangular arrangements of micro-pins and micro-grooves. These represent the first published reports on LPBF AM of copper wicking structures for HPs/VCs applications. The copper wicks were also successfully fabricated in multiple build directions. The fabricated wicks were then characterized by measuring porosity and permeability as well as conducting capillary rate-of-rise analysis. Results are compared with recently published works on AM for fabricated wicking structures in 316L stainless steel and AlSi12 aluminum material systems. The porosity of fabricated sintered-powder wicks ranged from 0.31 to 0.37, while the measured porosity for micro-pin and micro-groove wicks ranged from 0.55 to 0.85. Capillary performance K/reff achieved ranged from 0.186 μm to 1.79 μm, with the rectangular-arrangement micro-pin wick presenting the highest capillary performance. The results of this work indicate the viability of fabricating copper wicking structures via LPBF and provide foundational knowledge and experimental validation necessary for additively manufacturing complete assemblies of copper HPs and VCs.