Harsh Environment Applications Research Articles

Comparison study of time-varying seismic fragility of precast segmental and cast-in-place bridge columns in high-speed railway bridges

In recent years, precast segmental bridge columns (PSBCs) have been widely used in high-speed railway bridges, but the lack of long-term seismic performance limits PSBCs application in harsh environments and high-intensity areas. However, the selection of high-speed rail lines in high-intensity offshore areas is inevitable. Therefore, considering the impact of environmental erosion and earthquake, it is necessary to study the seismic performance of PSBC. In order to study the application of PSBCs in offshore high-intensity areas, this paper comprehensively compares the time-varying seismic fragility of PSBCs and cast-in-place bridge columns (CPBCs) in high-speed railway bridges. Based on offshore high-speed railway columns, the finite element models of representative PSBCs and CPBCs are established and verified by experiments. Then, the verified finite models are utilized to implement the time-varying fragility analysis by considering chloride ion erosion under four damage states. The main conclusions are as follows: the exceeding probabilities of PSBCs and CPBCs are close in intact bridges under different damage states and seismic intensities. With the prolongation of bridge service time, the steel bars corrosion rate of PSBCs is faster than that of CPBCs due to the discontinuity of PSBCs segments, the exceeding probabilities of PSBCs increase more rapidly than those of CPBCs. When the columns reach the design working life, the exceeding probability and PGA (Peak Ground Acceleration) median of PSBCs are higher than those of CPBCs under four damage states. Taking the moderate damage state as an example, the maximum exceeding probability of PSBCs and CPBCs were 97.2% and 89.1%, respectively, and the PGA median of PSBCs were 24% lower than that of CPBCs at 100 years. This work provides a theoretical foundation for the better application of PSBCs in offshore high-intensity areas.

Radiation-Resistant Er-Doped Fiber Based on Ge-Ce Co-Doping

We investigated the radiation responses of Ge-Ce co-doped erbium-doped fibers (EDFs) under gamma radiation with a dose up to 1000 Gy and a dose rate of 0.2 Gy/s. Three EDFs with low or high concentrations of Ge or Ce were fabricated by modified chemical vapor deposition (MCVD). The absorption spectra and amplification performance of the three Ge-Ce co-doped EDFs before and after radiation were tested and analyzed in detail. The radiation-induced absorption (RIA) can be dramatically weakened by heavily co-doping Ge and Ce, and 0.8 dB radiation-induced gain degradation at 1550 nm was obtained in the erbium-doped fiber amplifier (EDFA) with heavy Ge and Ce doping at a dose of 1000 Gy. Furthermore, the possible mechanism of Ce and Ge effects on radiation tolerance enhancement is discussed. Relevant results indicate that the Ge-Ce co-doped EDF has significant performance improvements in radiation resistance, making it ideal for applications in harsh radiation environments.

Amplifier Based on 4H-SiC MOSFET Operation at 500 °C for Harsh Environment Applications

Successful operation of 4H-silicon carbide (SiC) MOSFET and integrated electronic circuit based on 4H-SiC MOSFET is reported at temperature up to <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$500~^{\circ }\text{C}$ </tex-math></inline-formula> in air. The high-temperature operation of the integrated circuit (IC) based on 4H-SiC MOSFET strongly depends on the reliability of metal/SiC contact. Based on the transfer length method (TLM), the Ni/Nb/n-type 4H-SiC junction exhibits ohmic behavior with specific contact resistance of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1.86\times 10^{-{4}}\,\, \Omega \cdot $ </tex-math></inline-formula> cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> when operating at <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$500~^{\circ }\text{C}$ </tex-math></inline-formula> . In contrast, the voltage gain of the amplifier is strongly governed by the variation of carrier mobility of the 4H-SiC MOSFET when temperature varies from room temperature to <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$500~^{\circ }\text{C}$ </tex-math></inline-formula> . The experimental results show that, when the temperature is increased from <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$20~^{\circ }\text{C}$ </tex-math></inline-formula> to <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$300~^{\circ }\text{C}$ </tex-math></inline-formula> , the amplifier gain of the IC increased from 23.8 to 153.0. Though the voltage gain decreases when the temperature increases above <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$300~^{\circ }\text{C}$ </tex-math></inline-formula> , it is still higher than 50 at <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$500~^{\circ }\text{C}$ </tex-math></inline-formula> . These results indicate that integrated electronic circuits based on this 4H-SiC MOSFET technology could be potentially used for harsh environment applications.

Ultrasensitive Flexible κ-Phase Ga2O3 Solar-Blind Photodetector.

Flexible Ga2O3 photodetectors have attracted considerable interest owing to their potential use in the development of implantable, foldable, and wearable optoelectronics. In particular, β-phase Ga2O3 has been most widely investigated due to the highest thermodynamic stability. However, high-quality β-phase Ga2O3 relies on the ultrahigh crystallization temperature (usually ≥750 °C), beyond the thermal tolerance of most flexible substrates. In this work, we epitaxially grow a high-quality metastable κ-phase Ga2O3 (002) thin film on a flexible mica (001) substrate under 680 °C and develop a flexible κ-Ga2O3 thin film photodetector with ultrahigh performance. Epitaxial κ-Ga2O3 and the mica substrate are maintained to be thermally stable up to 750 °C, suggesting their potential for harsh environment applications. The responsivity, on/off ratio, detectivity, and external quantum efficiency of the fabricated photodetector are 703 A/W, 1.66 × 107, 4.08 × 1014 Jones, and 3.49 × 105 %, respectively, for 250 nm incident light and a 20 V bias voltage. These values are record-high values reported to date for flexible Ga2O3 photodetectors. Furthermore, the flexible photodetector shows robust flexibility for bending radii of 1, 2, and 3 cm. More importantly, it shows strong mechanical stability against 10,000 bending test cycles. These results reveal the significance of high-quality κ-phase Ga2O3 grown heteroepitaxially on a flexible mica substrate, especially its potential for use in future flexible solar-blind detection systems.

Mechanical Properties of High-Temperature Fiber-Reinforced Thermoset Composites with Plain Weave and Unidirectional Carbon Fiber Fillers

Fiber-reinforced thermoset composites are a class of materials that address the arising needs from the aerospace and hypersonic industries for high specific strength, temperature-resistant structural materials. Among the high-temperature resistant thermoset categories, phenolic triazine (PT) cyanate esters stand out thanks to their inherent high degradation temperature, glass transition temperature, and mechanical strength. Despite the outstanding properties of these thermosets, the performance of carbon fiber composites using PT cyanate esters as matrices has not been thoroughly characterized. This work evaluated PT and carbon fiber composites’ compressive properties and failure mechanisms with different fiber arrangements. A PT resin with both plain weave (PW) and non-crimped unidirectional (UD) carbon fiber mats was analyzed in this research. Highly loaded thermoset composites were obtained using process temperatures not exceeding 260 °C, and the composites proved to retain compressive strength at temperatures beyond 300 °C. Compressive testing revealed that PT composites retained compressive strength values of 50.4% of room temperature for UD composites and 61.4% for PW composites. Post-compressive failure observations of the gage section revealed that the mechanisms for failure evolved with temperature from brittle, delamination-dominant failure to shear-like failure promoted by the plastic failure of the matrix. This study demonstrated that PT composites are a good candidate for structural applications in harsh environments.

Flexible, conductive and multifunctional cotton fabric with surface wrinkled MXene/CNTs microstructure for electromagnetic interference shielding

Although ultrathin and flexible conductive textiles are promising for smart wearable electronic devices, the seamless integration of electromagnetic interference (EMI) shielding textiles, strain sensors and Joule heater is still a huge challenge. Herein, a conductive cotton fabric with cross-linked wrinkled microstructure is fabricated via a facile spray-coating approach, formed by carbon nanotubes (CNTs) as skeletons and Ti3C2Tx MXene nanosheets as stacking layers. Benefiting from the unique wrinkled microstructure, the resultant fabric exhibits high EMI shielding effectiveness (EMI SE) of 46.05 dB in the X-band at a thickness of only 138 µm. Furthermore, the specific EMI SE (SSE/t) of the resultant fabric is up to 6.71 × 103 dB cm2 g−1, significantly exceeding most of the currently reported polymeric EMI shielding materials. Due to the high electrical conductivity, the resultant fabric also displays excellent Joule heating performance (46.6 ℃ for PMC3C at the driven voltage of 2 V) and sensitive strain responses. More importantly, the resultant fabric demonstrates outstanding stability and anti-fouling property, offering a huge potential for long-term applications in harsh environments. This work provides a facile strategy to develop multifunctional EMI shielding fabric for human motion detection and personal thermal management.

Electron transfer dominated triboelectrification at the hydrophobic/slippery substrate—water interfaces

Triboelectric nanogenerator (TENG) based on triboelectrification has attracted wide attention due to its effective utilization of green energy sources such as marine energy. However, researches about liquid-liquid triboelectrification are still scanty as solid—liquid triboelectrification has been widely studied. Herein, this work focuses on the hydrophobic/slippery substrate—water interfacial triboelectrification based on the solid friction materials of polytetrafluoroethylene (PTFE) nanoparticles. The hydrophobic/slippery substrate—water interfacial triboelectrification are studied by assembling PTFE coated Al sheets and perfluoropolyether (PFPE) infused PTFE coated Al sheets (formed the slippery lubricant-infused surfaces (SLIPSs)) as the friction electrode, and water as liquid friction materials, respectively. The results show that the hydrophobic TENG output performances improved as the PTFE nanoparticles cumulating, and the SLIPSs TENG output performances increased with the thinner PFPE thickness. Both the triboelectrification behavior of hydrophobic/SLIPSs TENG assembled in this work are dominated by the electron transfer. Thanks to the introduction of SLIPSs, the SLIPSs TENG exhibits superior stability and durability than the hydrophobic TENG. The investigation of hydrophobic/slippery substrate—water interfacial triboelectrification contributes to optimize the TENG performances, and expands the application in harsh environments including low temperature and high humidity on the ocean.

Robust highly conductive fabric with fluorine-free healable superhydrophobicity for the efficient deicing of outdoor’s equipment

Conductive materials with superhydrophobicity surfaces emerge a superior application potential in outdoor’s equipment deicing field due to their excellent electrothermal heating capacity. However, it is still a challenge to develop robust conductive fabric with self-healing superhydrophobic surface for the application in outdoor harsh environments, especially using environment-friendly raw materials and facile modification methods. In this paper, the durable and washable conductive fabric (S-SHCNF) with desired electrothermal performance was fabricated through the design of healable superhydrophobic micro/nano rough surface. The introduction of nonfluorinated shell-core nanospheres (SiO2 @NH2-PDMS) with self-healing superhydrophobicity improved anti-corrosion and rapid restoration of S-SHCNF. The contact angle of the S-SHCNF could reach 158.2° while the sliding contact angle was 2.7°, endowing the materials with excellent anti-corrosion performance. As expected, the superhydrophobicity and conductivity of S-SHNCF kept unchanged when it has been exposed to strong acid, alkali and salt. Meanwhile, the S-SHCNF still maintained superhydrophobicity (151.5°) and conductivity (0.96 Ω·sq−1) after 800 cyclic frictions with the self-healing property. Thanks to the electrothermal performance from the Ag conductive dense layer, the S-SHCNF could remove ice thoroughly in 18 s with 5 V voltage. Therefore, the S-SHCNF with excellent durability and anticorrosive performance, could enlarge its application in outdoor deicing application especially in harsh environments.

Assessment of Epoxy Functionalized Poly(dimethylsiloxane) Vitrimers Catalyzed with Covalently Attached Amines as Reversible Adhesives

AbstractIn this work, vitrimeric elastomers based on functionalized poly(dimethylsiloxane) are realized. By exploiting reactions of epoxide functional groups with carboxylic acids in the presence of a covalently bonded amine catalyst, dynamic networks are formed to establish their potential in reversible adhesives. The dynamic nature of the networks is characterized thermo‐mechanically, and in tensile tests 85% of the stress at break can be recovered after reprocessing. The covalent adaptable networks are further subjected to damp heat tests, temperature cycling tests, and high temperature storage with the aim to establish the potential and boundaries of the dynamic character of the network after application in harsh environments. The influence of the ageing tests on the reprocessability and mechanical properties is evaluated via infrared spectroscopy and lap‐shear tests. While the damp heat tests (85 °C, 85% relative humidity, and 2000 h duration) lead to hydrolytic bond cleavage of the ester bonds and storage at 120 °C for 930 h oxidizes the hydroxy groups, temperature cycling tests (−40 to 85 °C, 50 cycles) does not degrade the mechanical properties and the dynamic nature of the networks and rejoined lap‐shear specimen exhibit a remaining bond strength of more than 70%.

Self-Detachable Through-Metal Acoustic Wireless Power Transfer

Unlike electromagnetic waves, acoustic vibrations waves can be used to transfer power directly through metal structures without being shielded. In this paper, a novel design of a self-detachable acoustic wireless power transfer system that can be used to transfer power through the thickness of a steel plate is presented, which does not require the use of any couplant. Electro-permanent-magnets (EPM's) were used to provide magnetic clamping force along the perimeter of the receiver transducer disc to enhance the coupling to the steel plate, while the transmitter transducer was bonded to the other side of the plate. The EPM clamping force can be switched on/off electronically with low power consumption. Unlike past work reliant on additional bonding materials or liquid/gel couplant, this approach enables the receiver to be attached and detached at will, opening up the possibility of a simple charging pad for unmanned aerial vehicles (UAVs) or other consumer devices for harsh environment applications. Power transfer efficiency up to 63% was achieved, and the effect of varying steel plate thickness and clamping force was also investigated. A finite element model was also constructed to understand the vibration mode shape.

A tube-shaped solid–liquid-interfaced triboelectric–electromagnetic hybrid nanogenerator for efficient ocean wave energy harvesting

Ocean waves, the most widely distributed energy source within the marine environment, promise renewable energy for next-generation self-sufficient ocean exploration and monitoring instrumentation. Triboelectric nanogenerator (TENG) technology has shown the potential in harvesting ocean wave energy. However, most TENG designs suffer from challenges such as relatively low contact intimacy and energy power density, limiting their practical application. This paper proposes a solid–liquid-interfaced, tube-shaped triboelectric–electromagnetic hybrid nanogenerator (TTEHG) to efficiently capture wave energy. Owing to the solid–liquid interface in conjunction with the coupled TENG and the electromagnetic generator (EMG) design, the TTEHG features a reduced frictional loss and broadened range of harvestable wave energy. At a frequency of 1 Hz, the instantaneous power density and current density of the TTEHG are 0.25 mW·cm–3 and 5 mA·cm–3, respectively. Even at an ultra-low operational frequency of 0.2 Hz, the TTEHG exhibits an excellent output performance with a peak current of nearly 15 mA, and is able to power various functional electronic devices, such as temperature and humidity sensors, to monitor the marine environment. The TTEHG was deployed in Sanya Bay, China, to demonstrate its practical application in harsh ocean environments.

Well‐dispersed poly(ether‐ether‐ketone)/multi‐walled carbon nanotubes nanocomposite for harsh environment applications

Reinforcing poly(ether-ether-ketone) (PEEK) with multi-walled carbon nanotubes (MWCNT) is of great interest for harsh environment applications, such as seals for oil and gas recovery because of its expected superior thermal and mechanical properties and environmental stability. In this research, a PEEK nanocomposite containing 10 wt% of well-dispersed MWCNT was successfully prepared using a solution mixing approach. Compared to a commercial PEEK/PBI (polybenzimidazole) blend benchmark, PEEK/MWCNT exhibits significantly increased Young's modulus, much lower water absorption, and better modulus retention under hot-wet conditions. Based on a physics-based Ngai's Coupling model and calculation of activation energy on stress relaxation, PEEK/MWCNT system shows stronger intermolecular interaction and higher energy barrier for chain mobility than PEEK/PBI system under hot-wet environment. These enhanced properties of PEEK/MWCNT nanocomposite are suitable for many high performance, harsh environment applications.

Flexible and tough zirconia-based nanofibrous membranes for thermal insulation

Ceramic nanofibrous materials with both good flexibility and robust mechanical properties are highly desired for harsh environment applications. Herein, we present ZrO2–SiO2 nanofibrous membranes by combining sol-gel and electrospinning methods and introducing amorphous components into crystalline zirconia. The fluffy stacking morphology structure and the mixture of amorphous SiO2 and crystalline ZrO2 contribute to the excellent mechanical properties with high flexibility, large tensile strain, and significantly improved fracture toughness (0.32 MJ m−3), which is rarely reported in ceramic nanofibrous materials at present. Furthermore, the resulting membranes show good fatigue resistance during 500 buckling cycles and maintain 90% of the original stress. Combined with the high-temperature resistance and low thermal conductivity (0.034 W m−1 K−1), the robust mechanical performances facilitate the ceramic nanofibrous membranes a promising candidate for the applications in harsh environments.

Water-Induced Self-Assembly and In Situ Mineralization within Plant Phenolic Glycol-Gel toward Ultrastrong and Multifunctional Thermal Insulating Aerogels.

Biopolymer/silica nanocomposite aerogels are highly attractive as thermally insulating materials for prevailing energy-saving engineering but are usually plagued by their lack of mechanical strength and environmental stability. Lignin is an appealing plant phenolic biopolymer due to its natural abundance, high stiffness, water repellency, and thermostability. However, integrating lignin and silica into high-performance 3D hybrid aerogels remains a substantial challenge due to the unstable co-sol process. In diatoms, the silicic acid stabilization prior to the condensation reaction is enhanced by the intervention of biomolecules in noncovalent interactions. Inspired by this mechanism, we herein rationally design an ultrastrong silica-mineralized lignin nanocomposite aerogel (LigSi) with an adjustable multilevel micro/nanostructure and arbitrary machinability through an unusual water-induced self-assembly and in situ mineralization based on ethylene glycol-stabilized lignin/siloxane colloid. The optimized LigSi exhibits an ultrahigh stiffness (a specific modulus of ∼376.3 kN m kg-1) and can support over 5000 times its own weight without obvious deformation. Moreover, the aerogel demonstrates a combination of outstanding properties, including superior and humidity-tolerant thermal insulation (maintained at ∼0.04 W m-1 K-1 under a relative humidity of 33-94%), excellent fire resistance withstanding an ∼1200 °C flame without disintegration, low near-infrared absorption (∼9%), and intrinsic self-cleaning/superhydrophobic performance (158° WCA). These advanced properties make it an ideal thermally insulating material for diversified applications in harsh environments. As a proof of concept, a dual-mode LigSi thermal device was designed to demonstrate the application prospect of combining passive heat-trapping and active heating in the building.

High-Accuracy Online Calibration Scheme for Large-Scale Integrated Photonic Interferometric Measurements

High-accuracy interferometric measurement is crucial for integrated photonic interferometric imaging. In this paper, we propose an online calibration approach for large-scale integrated photonic beam combination that can realize high-accuracy measurement. By leveraging a simple four-step switching condition and the optical path differences between interferometric beams, the instrumental characteristics of the beam combiner, including the transmittances, visibilities, and phase relations, could be calibrated accurately. Compared to the conventional approach, the calibration procedure and estimation method are greatly simplified in our proposed scheme. The effectiveness of the proposed approach is validated using a photonic integrated circuit with two interferometric channels. The calibration results show that the differences between the phase relations are less than 1.41% between the proposed and conventional approaches. The proposed scheme shows significant advantages in optical synthetic aperture imaging systems using photonic integrated circuits especially for applications in harsh environments.

Guided-Mode-Resonance Reflectors for Performance Enhancement of Sapphire Based Fabry-Perot Sensors in Harsh Environment

This paper presents a guided-mode resonance (GMR) reflector for sapphire based Fabry-Perot (F-P) sensors that enables tunable or wideband high reflectance with high temperature resistance,which is expected to effectively regulate the performance of F-P sensors and offer a novel approach for designing F-P sensors in harsh environments. Intrinsic and extrinsic GMR gratings are proposed, and their optical and thermal properties are investigated and compared through numerical simulations, such as rigorous coupled-wave analysis and finite element analysis methods. The quantitative results indicate high feasibility for harsh environment applications and the potential for adopting different demodulation methods. Significant enhancement in the F-P sensor performance is obtained through analysis based on the F-P interference model, and the spectrum fineness and sensor sensitivity can be enhanced by at least one order of magnitude. The GMR reflector can be extended to other types of F-P sensors, demonstrating significant potential in high-temperature applications.

A dual LC resonant circuit integrated wireless passive force and temperature sensor for harsh-environment applications

This paper proposes a dual inductor-capacitor (LC) circuit integrated wireless and passive force and temperature sensor for the simultaneous measurement of force and temperature in high-temperature environments. The sensor is fabricated by a two-step process: the preparation of the Al2O3 substrate and the fabrication of the dual LC sensor with Ag paste using screen-printing technology and metallization. The variation in ambient force and temperature can be detected wirelessly by extracting the resonant frequencies of the antenna. The sensor can work in the force range of 0–10 N and temperature range of 25–500 °C with a maximum force sensitivity of 107 kHz/N at 500 °C and temperature sensitivity of 21.7 kHz/°C. To precisely measure the force, the temperature compensation method is proposed. The sensor has the advantages of low cost, simple fabrication and test, and high stability and repeatability, which are promising for the force and temperature application on the engine turbine blade in high-temperature environments.

Monolithic Integration of Graphene in SiC Radiation Sensors for Harsh-Environment Applications

Due to their low leakage current, low noise levels, high thermal conductivity, and potential radiation hardness, SiC devices offer various advantages over Si devices in certain applications. As a result, they are being considered for operation in harsh environments, such as plasma diagnostic systems in future nuclear fusion reactors or in high energy physics applications. We report on relevant results of the GRACE project, which seeks to deliver a new generation of SiC sensors with graphene-enhanced contacts. Such devices are aimed to be radiation-hard and functional at high temperatures. The work presented in this paper focuses on the optimisation of the electrical contacts, along with the electrical characterisation and radiation-tolerance assessment of the first sensor prototypes produced.

Selective laser melting of WC-Co reinforced AISI 1045 steel composites: microstructure characterization and mechanical properties

Due to the limited wear resistance, AISI 1045 steel has limited applications in harsh environments, and the friction effect leads to premature scrapping. In order to improve the mechanical properties of AISI1045 steel, in this study, WC-Co particles reinforced AISI 1045 steel composites were produced by selective laser melting (SLM), and mainly focused on the influence of laser line energy density (LED) on the microstructure and mechanical properties in detail. The Vickers hardness test and rotational friction test were conducted to determine the Vickers hardness and friction resistance properties of composites. Results demonstrated that the SLM 500 J/m WC-Co/AISI 1045 steel composites possesses higher Vickers hardness and wear resistance compared to that of other samples owing to the finer grains and higher relative density. Herein, the wear mechanism and the binding interface of the SLM composites was also deeply discussed in this paper.

Boron-modified perhydropolysilazane towards facile synthesis of amorphous SiBN ceramic with excellent thermal stability

SiBN ceramics are widely considered to be the most promising material for microwave-transparent applications in harsh environments owing to its excellent thermal stability and low dielectric constant. This work focuses on the synthesis and ceramization of single-source precursors for the preparation of SiBN ceramics as well as the investigation of the corresponding microstructural evolution at high temperatures including molecular dynamic simulations. Carbon- and chlorine-free perhydropolysilazanes were reacted with borane dimethyl sulfide complex at different molar ratios to synthesize single-source precursors, which were subsequently pyrolyzed and annealed under N2 atmosphere (without ammonolysis) to prepare SiBN ceramics at 1100, 1200, and 1300 °C with high ceramic yield in contrast to previously widely-used ammonolysis synthesis process. The obtained amorphous SiBN ceramics were shown to have remarkably improved thermal stability and oxidation resistance compared to amorphous silicon nitride. Particularly, the experimental results have been combined with molecular dynamics simulation to further study the amorphous structure of SiBN and the atomic-scale diffusion behavior of Si, B, and N at 1300 °C. Incorporation of boron into the Si—N network is found to suppress the crystallization of the formed amorphous silicon nitride and hence improves its thermal stability in N2 atmosphere.