| 1. |
- Luo, Xin, 1983, et al.
(författare)
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Boron nitride nanofiber and indium composite based thermal interface materials for electronics heat dissipation applications
- 2014
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Ingår i: Journal of Materials Science: Materials in Electronics. - 1573-482X .- 0957-4522. ; 25:5, s. 2333-2338
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Tidskriftsartikel (refereegranskat)abstract
- With increased power density and continued miniaturization, effective thermal dissipation is of significant importance for operational lifetime and reliability of electronic system. Advanced thermal interface materials (TIMs) with excellent thermal performance need to be designed and developed. Here we report novel TIMs consisted of boron nitride (BN) nanofibers and pure indium (In) solder for heat dissipation applications. The BN nanofibers are fabricated by electrospinning process and nitridation treatment. After surface metallization by sputtering, the porous BN film is infiltrated with liquid indium by squeeze casting to form the final solid composites. The new composites show the in-plane and through-plane thermal conductivity respectively of 60 and 20 W/m K. The direction dependence thermal properties of the TIM are due to the anisotropic thermal performance of BN nanofibers in the composite. A low thermal contact resistance of 0.2 K mm2/W is also achieved at the interface between this new composite and copper substrate. These competent thermal properties demonstrate the great potential of the BN–In TIMs in thermal management for electronic system.
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| 2. |
- Luo, Xin, 1983, et al.
(författare)
-
Novel thermal interface materials: boron nitride nanofiber and indium composites for electronics heat dissipation applications
- 2014
-
Ingår i: Journal of Materials Science: Materials in Electronics. - : Springer Science and Business Media LLC. - 1573-482X .- 0957-4522. ; 25:5, s. 2333-2338
-
Tidskriftsartikel (refereegranskat)abstract
- With increased power density and continued miniaturization, effective thermal dissipation is of significant importance for operational lifetime and reliability of electronic system. Advanced thermal interface materials (TIMs) with excellent thermal performance need to be designed and developed. Here we report novel TIMs consisted of boron nitride (BN) nanofibers and pure indium (In) solder for heat dissipation applications. The BN nanofibers are fabricated by electrospinning process and nitridation treatment. After surface metallization by sputtering, the porous BN film is infiltrated with liquid indium by squeeze casting to form the final solid composites. The new composites show the in-plane and through-plane thermal conductivity respectively of 60 and 20 W/m K. The direction dependence thermal properties of the TIM are due to the anisotropic thermal performance of BN nanofibers in the composite. A low thermal contact resistance of 0.2 K mm(2)/W is also achieved at the interface between this new composite and copper substrate. These competent thermal properties demonstrate the great potential of the BN-In TIMs in thermal management for electronic system.
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| 3. |
- Yong-an, Min, et al.
(författare)
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Oxidation and Thermal Fatigue Behaviors of Two Type Hot Work Steels During Thermal Cycling
- 2013
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Ingår i: Journal of Iron and Steel Research International. - 1006-706X .- 2210-3988. ; 20:11, s. 90-97
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Tidskriftsartikel (refereegranskat)abstract
- Thermal fatigue test has been carried out on widely used hot work steel 4Cr5MoSiV1 and a low alloyed steel 3Cr3MoV in temperature range of 200 to 700 degrees C. Tempering resistance, as well as high temperature hardness/strength of steel specimens, works as a dominating material parameter on thermal fatigue resistance. During the heating period, high hardness can depress the inelastic deformation. This deformation is the origination of tensile stress, which acts as the driving force of heat checking during the cooling period. The cyclic strain-oxidation interaction can speed up the damage on surface defects, which plays an obvious role in initiation of thermal cracks. On 4Cr5MoSiV1 steel specimens, borders between the matrix and inclusions such as titanium compounds, or lager carbides such as primary carbides, are focused by strain and attacked by oxidation, and are main initiating places of cracks. While on 3Cr3MoV steel specimens, larger strain causes plastic deformation concentrating around grain boundaries. Then the following oxidation accelerates this grain boundary damage and creates cracks.
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| 4. |
- An, T., et al.
(författare)
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Analysis on microstructure and friction wear performance of chromium carbide/Ni 3Al composite surfacing layer
- 2012
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Ingår i: Hanjie Xuebao/Transactions of the China Welding Institution. - 0253-360X. ; 33:2, s. 101-104
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Tidskriftsartikel (refereegranskat)abstract
- Microstructure of chromium carbide reinforced Ni 3Al-based matrix composite coating prepared by argon tungsten-arc welding was investigated with optical microscope, scanning electron microscopy (SEM), electron probe micro-analysis (EPMA) and X-ray diffraction (XRD). The wear performance of the coating and cast iron of piston ring were tested by a Pin-on-Disc tribometer. The results indicated that the Ni 3Al-based matrix was formed during welding, a large number of fine carbide particles such as Cr 3C 2 and Cr 7C 3 dispersed in it; The particle of Cr 3C 2 in welding wire was dissolved and re-precipitated during hardfacing. The re-precipitation of chromium carbide particle contains Fe, Ni elements and forms strong metallurgically bond with Ni 3Al-based matrix. Diffuse distribution of chromium carbide particles and Cr solid-solution in Ni 3Al-based matrix, makes the surfacing layer with higher hardness. The hardfaceing layer shows excellent dry friction wear resistance and its friction coefficient is 0.23, lower than 0.39 which is the friction coefficient of piston material of vermicular graphite cast iron. The wear rate of hardfaceing layer is only 43 percent of vermicular graphite cast iron.
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| 5. |
- Pecunia, Vincenzo, et al.
(författare)
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Roadmap on energy harvesting materials
- 2023
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Ingår i: Journal of Physics. - : IOP Publishing. - 2515-7639. ; 6:4
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Tidskriftsartikel (refereegranskat)abstract
- Ambient energy harvesting has great potential to contribute to sustainable development and address growing environmental challenges. Converting waste energy from energy-intensive processes and systems (e.g. combustion engines and furnaces) is crucial to reducing their environmental impact and achieving net-zero emissions. Compact energy harvesters will also be key to powering the exponentially growing smart devices ecosystem that is part of the Internet of Things, thus enabling futuristic applications that can improve our quality of life (e.g. smart homes, smart cities, smart manufacturing, and smart healthcare). To achieve these goals, innovative materials are needed to efficiently convert ambient energy into electricity through various physical mechanisms, such as the photovoltaic effect, thermoelectricity, piezoelectricity, triboelectricity, and radiofrequency wireless power transfer. By bringing together the perspectives of experts in various types of energy harvesting materials, this Roadmap provides extensive insights into recent advances and present challenges in the field. Additionally, the Roadmap analyses the key performance metrics of these technologies in relation to their ultimate energy conversion limits. Building on these insights, the Roadmap outlines promising directions for future research to fully harness the potential of energy harvesting materials for green energy anytime, anywhere.
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