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The thermophysical properties of 1D micro/nanoscale materials could differ significantly from those of their bulk counterparts due to intensive energy carrier scattering by structures. This work provides an in-depth review of cutting-edge techniques employed for transient characterization of thermophysical properties at the micro/nanoscale scale. In terms of transient excitation, step Joule heating, step laser heating, pulsed laser heating, and frequency domain amplitude-modulated laser heating are covered. For thermal probing, electrical and Raman scattering-based physical principles are used. These techniques enable the measurement of thermal conductivity, thermal diffusivity, and specific heat from the sub-mm level down to the atomic level (single-atom thickness). This review emphasizes the advantages of these techniques over steady state techniques and their physics, challenges, and potential applications, highlighting their significance in unraveling the intricate thermal transport phenomena to the atomic level of 1D materials.
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Thermal behavior of materials in laser-assisted extreme manufacturing: Raman-based novel characterization
Abstract Laser-assisted manufacturing (LAM) is a technique that performs machining of materials using a laser heating process. During the process, temperatures can rise above over 2000 °C. As a result, it is crucial to explore the thermal behavior of materials under such high temperatures to understand the physics behind LAM and provide feedback for manufacturing optimization. Raman spectroscopy, which is widely used for structure characterization, can provide a novel way to measure temperature during LAM. In this review, we discuss the mechanism of Raman-based temperature probing, its calibration, and sources of uncertainty/error, and how to control them. We critically review the Raman-based temperature measurement considering the spatial resolution under near-field optical heating and surface structure-induced asymmetries. As another critical aspect of Raman-based temperature measurement, temporal resolution is also reviewed to cover various ways of realizing ultrafast thermal probing. We conclude with a detailed outlook on Raman-based temperature probing in LAM and issues that need special attention.
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- Award ID(s):
- 1930866
- PAR ID:
- 10303670
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- International Journal of Extreme Manufacturing
- Volume:
- 2
- Issue:
- 3
- ISSN:
- 2631-8644
- Page Range / eLocation ID:
- Article No. 032004
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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