Silicon carbide (SiC) fibers are widely used as a reinforcement in ceramic matrix composites due to their high mechanical strength and superior thermal resistance. Here, we investigate the rapid radio frequency (RF) heating response of two types of SiC fibers (Hi-Nicalon and Sylramic) in the 1-200 MHz frequency range. Hi-Nicalon fibers exhibit a surprisingly rapid RF heating response of 240 °C/s in the perpendicular orientation, and this property could be exploited for oven-free and noncontact processing of composites with SiC fibers. The presence of excess carbon on the surface of Hi-Nicalon fibers is most likely responsible for the RF heating response and significantly higher temperatures in the parallel as compared to perpendicular alignment of fibers to the electric field. The RF heating response of Hi-Nicalon SiC fibers was utilized to heat preceramic polymers (polycarbosilanes) infiltrated in SiC fibers and cure them to ceramic matrix composites (CMCs) using RF applicators. A noncontact RF heating setup to pyrolyze the precursor polymers under inert conditions and make SiC/SiC composites is also developed.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/acsami.9b14971 | DOI Listing |
Carbohydr Polym
March 2025
Institute of Zhejiang University-Quzhou, 99 Zheda Road, Quzhou 324000, China; National Key Laboratory of Biobased Transportation Fuel Technology, College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China. Electronic address:
Cellulose has outstanding potential for application in energy storage batteries due to its high temperature resistance, high electrolyte affinity, renewability, and suppression of the shuttle effect, but single cellulose membranes still suffer from problems such as inhomogeneous pore distribution and unstable three-dimensional network structure. In this study, a green and sustainable regenerative cellulose (RC)/sodium alginate (SA) gel electrolyte membrane is developed by sol-gel process, the double crosslinked network scaffold centered on Zn was constructed by the synergistic hydrogen-bonding and metal ion- coordination network, the stable and uniform pore structure was also formed. The obtained RC-SA gel electrolyte membrane exhibits outstanding performance, featuring a dual crosslinked network with abundant pore structure and numerous polar groups that effectively enhance Zn transport, significantly improving battery cycling performance.
View Article and Find Full Text PDFMaterials (Basel)
December 2024
Aerospace Research Institute of Materials and Processing Technology, Beijing 100076, China.
Carbon-fiber-reinforced carbon and silicon carbide (C/C-SiC) composites were prepared using chemical vapor infiltration (CVI) combined with reactive melt infiltration (RMI). The microstructure and flexural properties of C/C-SiC composites after oxidation in different temperature water vapor environments were studied. The results indicate that the difficulty of oxidation in water vapor can be ranked from easy to difficult in the following order: carbon fiber (CF), pyrolytic carbon (PyC), and ceramic phase.
View Article and Find Full Text PDFMaterials (Basel)
November 2024
Zhejiang Key Laboratory of Data-Driven High-Safety Energy Materials and Applications, Ningbo Key Laboratory of Special Energy Materials and Chemistry, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China.
This study investigated the influence of preformed composition and pore size on the microstructure and properties of SiC/SiC composites fabricated via reactive melt infiltration (RMI). The process began with the impregnation of SiC fiber cloth with phenolic resin, followed by lamination and pyrolysis. Subsequent steps included further impregnations with phenolic resin, SiC slurry, and carbon black slurry, each followed by additional pyrolysis.
View Article and Find Full Text PDFMaterials (Basel)
October 2024
Key Laboratory of High Performance Ceramic Fibers, Xiamen University, Xiamen 361005, China.
A dense monolithic SiC/(HfTaZrNb)C/C high-entropy ceramic nanocomposite was prepared using a polymer-derived ceramic (PDC) method combined with spark plasma sintering (SPS). The microstructural evolution and mechanical properties of the obtained nanocomposites were characterized by X-ray diffractometer (XRD), transmission electron microscope (TEM), scanning-electron microscope (SEM), and nanoindentation. The results indicate that the phase composition of SiC/(HfTaZrNb)C/C can be adjusted by modifying the metal content of the single-source precursor (SSP) through molecular design.
View Article and Find Full Text PDFNanomaterials (Basel)
October 2024
State Key Laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China.
A new type of SiC/TiC-TiSiC composite was prepared by the Spark Plasma Sintering (SPS) method in this work. The phase transformation and interface cracking of this composite under ion irradiation (single Xe, Xe + He, and Xe + He + H ions) and subsequent annealing were analyzed using transmission electron microscopy (TEM), mainly focusing on the interface regions. Xe ion irradiation resulted in the formation of high-density stacking faults in the TiC coatings and the complete amorphization of SiC fibers.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!