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Abstract One of the major challenges in the development of micro-combustors is heat losses that result in flame quenching, and reduced combustion efficiency and performance. In this work, a novel thermal barrier coating (TBC) using hexagonal boron nitride (h-BN) nanosheets as building blocks was developed and applied to a Swiss roll micro-combustor for determining its heat losses with increased temperatures inside the combustor that contributes to improved performance. It was found that by using the h-BN TBC, the combustion temperature of the micro-combustor increased from 850 K to 970 K under the same thermal loading and operational conditions. This remarkable temperature increase using the BN TBC originated from its low cross-plane thermal conductivity of 0.4 W m−1 K−1to mitigate the heat loss from the micro-combustor plates. Such a low thermal conductivity in the h-BN TBC is attributed to its interfacial resistance between the nanosheets. The development of h-BN TBC provides an effective approach to improve thermal management for performance improvements of gas turbine engines, rocket engines, and all various kinds of micro-combustors.
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This content will become publicly available on February 1, 2026
Enhanced Thermal Management in Microelectronics Packaging With 2D h‐BN Nanocomposite Underfills
ABSTRACT The quest for faster and more densely packed microelectronic circuits has necessitated significant advancements in thermal management and encapsulant manufacturing technologies. This pursuit has driven the development of innovative methods to enhance heat flux and thermal transfer in microelectronics packaging. A critical issue is the thermal stress induced by the coefficient of thermal expansion (CTE) mismatch between the chip and the substrate, threatening the chip's mechanical integrity and lifespan. To address this challenge, there is a growing emphasis on using underfills to improve thermal transfer and heat dissipation. The current study focuses on using hexagonal boron nitride (h‐BN) nanofillers for robust thermal support in microelectronics packaging. This study deploys epoxy adhesives to integrate nanofillers, where precise dispersion is crucial for optimizing thermal and mechanical properties. Findings show 1500‐ and 500‐nm h‐BN enhance axial thermal conductivity and diffusivity linearly with filler content, while the 70‐nm h‐BN plateaus at 3% volume. The 70‐nm h‐BN demonstrates superior radial thermal performance.
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- Award ID(s):
- 2435570
- PAR ID:
- 10636178
- Publisher / Repository:
- Nano Select
- Date Published:
- Journal Name:
- Nano Select
- Volume:
- 6
- Issue:
- 2
- ISSN:
- 2688-4011
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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