Modulation of the thermal transport of micro-structured materials from 3D printing

Abstract

It is desirable to fabricate materials with adjustable physical properties that can be used in different industrial applications. Since the property of a material is highly dependent on its inner structure, the understanding of structure–property correlation is critical to the design of engineering materials. 3D printing appears as a mature method to effectively produce micro-structured materials. In this work, we created different stainless-steel microstructures by adjusting the speed of 3D printing and studied the relationship between thermal property and printing speed. Our microstructure study demonstrates that highly porous structures appear at higher speeds, and there is a nearly linear relationship between porosity and printing speed. The thermal conductivity of samples fabricated by different printing speeds is characterized. Then, the correlation between porosity, thermal conductivity, and scanning speed is established. Based on this correlation, the thermal conductivity of a sample can be predicted from its printing speed. We fabricated a new sample at a different speed, and the thermal conductivity measurement agrees well with the value predicted from the correlation. To explore thermal transport physics, the effects of pore structure and temperature on the thermal performance of the printed block are also studied. Our work demonstrates that the combination of the 3D printing technique and the printing speed control can regulate the thermophysical properties of materials.

Ballistic Thermal Transport at Sub‐10 nm Laser‐Induced Hot Spots in GaN Crystal

“…The temperature increase in the uncoated silicon tip case mainly derives from the heating effect of the Raman laser, and can be approximately estimated through the simple heat conduction model. [ 39 ] The temperature rise in a small region of a semi‐infinite medium under a constant heat flux can be calculated as $${\theta }_\infty = \frac{2}{{{\pi}}} \cdot \frac{{{q}_0a}}{k}$$, where k is the thermal conductivity of the material, q 0 is the constant heat flux, a is the spot radius, and θ ∞ is the temperature increase in the small region after thermal equilibrium. The laser spot radius is ~30 µm and the constant heat flux can be calculated from the heating power (13.8 mW) of the incident laser.…”

“…The temperature increase in the uncoated silicon tip case mainly derives from the heating effect of the Raman laser, and can be approximately estimated through the simple heat conduction model. [39] The temperature rise in a small region of a semi-infinite medium under a constant heat flux can be calculated as…”

Performance improvement of three-body radiative diodes driven by graphene surface plasmon polaritons

“…[16][17][18] In recent years, phase transition materials have shown extraordinary advantages in modulating near-field radiative heat flux due to the non-linear dependence of physical properties on temperature. 19,20 Furthermore, phase transition materials with the ability to exhibit different states have been utilized in the development of radiative thermal diodes. [21][22][23] Vanadium dioxide (VO 2 ), as a phase transition material, has been numerically demonstrated to be able to modulate near-field radiative heat flux by orders of magnitude upon rectification from the metallic to the insulating phase.…”

Evaluation of Effective Heat Transport and Temperature Gradients in Thermally Anisotropic Particulate Arrangements

“…To mitigate such issues, elaborate thermal management systems are developed and tested . However, the first steps toward safer and more robust applications can already be made at the level of the microstructure. , …”

“…30 However, the first steps toward safer and more robust applications can already be made at the level of the microstructure. 31,32 Here, we work out the relevance of intrinsic anisotropy and orientation to the macroscopic performance of colloidal mixtures. We used a binary mixture as a model system.…”