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Developing high‐efficiency electromagnetic wave absorption with broad temperature adaptability in polymeric nanocomposites remains significant challenge despite urgent practical demands. Here, a new type of poly(ether ether ketone) (PEEK) composites integrated with magnetic carbon nanofillers of Fe3O4/carbon nanotubes/reduced graphene oxide are innovatively fabricated via the facile strategy. These multifunctional nanofillers collaboratively induce synergistic magnetic, conductive, and interfacial polarization losses, while maintaining structural integrity at high temperatures. Benefiting from this rational design, the resulting PEEK‐based composites exhibit outstanding absorption performance across 298–573 K. A minimum reflection loss (RLmin) of −66.62 dB and an effective absorption bandwidth (EAB) of 4.58 GHz are achieved at room temperature, while a comparable performance involving RLmin of −66.01 dB and EABmax of 4.05 GHz (8.20–12.25 GHz) is maintained even at 573 K, nearly covering the full X‐band, surpassing previously reported polymer composites at such a high temperature. This work opens up a novel pathway to engineer multifunctional polymer composites combining structural and electromagnetic functionalities at a wide temperature range. Herein, thermally robust poly(ether ether ketone)‐based composites reinforced by a hierarchical Fe3O4/carbon nanotubes/reduced graphene oxide (Fe3O4/CNTs/rGO) network are reported, delivering wide‐temperature‐range broadband electromagnetic wave absorption (298–573 K; minimum reflection loss (RLmin) ≈ −66 dB). CNT‐involved heterogeneous interfaces dominate dielectric loss, while Fe3O4 provides ferromagnetic loss. Moreover, the additive‐manufacturing‐compatible platform paves the way for structural–functional integration in aerospace.

The current review investigates employing magnetron sputtering techniques to create nanostructured thermal barrier coatings (TBCs) manufactured on the nickel‐based superalloy, Superni 718, which is usually used to manufacture turbine parts that lay under extremely high thermal and mechanical stresses. Versus conventional coating techniques, Magnetron sputtering provides increased density and microstructure control of the coating which translates to better thermal insulation, oxidation resistance and better cyclic properties. Some of the ceramic materials employed include yttria‐stabilized zirconia (YSZ) which has a low thermal conductivity (<1.71 W/m K) in addition to stability at high temperatures approximately 900°C. This is also along with the role of NiCoCrAlY bonding coats in adhesion promotion and minimizational of thermal mismatch. Major depositing parameters like working pressure, substrate temperature and sputtering mode are sharply investigated. Recent advances in high power impulse magnetron sputtering (HiPIMS) as well as the tailored bond coat design discussions are also presented in the review. Lastly, it combines material selection and deposition strategies and determines the gaps in research of in situ diagnostics and multi‐parameter optimization of high‐performance ceramic coating. This review highlights recent advances in magnetron‐sputtered ceramic thermal barrier coatings for Superni 718, emphasizing improved thermal insulation, oxidation resistance, and durability. Key deposition parameters and emerging techniques like HiPIMS are critically discussed with a focus on coating performance under extreme operating conditions.

This research aims to explore the high-temperature and low-temperature performances of lignin–waste engine oil-modified asphalt binder and its mixture. For this research, the lignin with two contents (4%, 6%) and waste engine oil with two contents (3%, 5%) were adopted to modify the control asphalt binder (PG 58-28). The high-temperature rheological properties of the lignin–waste engine oil-modified asphalt binder were investigated by the viscosity obtained by the Brookfield viscometer and the temperature sweep test by the dynamic shear rheometer. The low-temperature rheological property of the lignin–waste engine oil-modified asphalt binder was evaluated by the stiffness and m-value at two different temperatures (−18 °C, −12 °C) obtained by the bending beam rheometer. The high-temperature and the low-temperature performances of the lignin–waste engine oil-modified asphalt mixture were explored by the rutting test and low-temperature bending beam test. The results displayed that the rotational viscosity and rutting factor improved with the addition of lignin and decreased with the incorporation of waste engine oil. Adding the lignin into the control asphalt binder enhanced the elastic component while adding the waste engine oil lowered the elastic component of the asphalt binder. The stiffness of asphalt binder LO60 could not meet the requirement in the specification, but the waste engine oil made it reach the requirement based on the bending beam rheometer test. The waste engine oil could enhance the low-temperature performance. The dynamic stabilities of LO40- and LO60-modified asphalt mixture increased by about 9.05% and 17.41%, compared to the control mixture, respectively. The maximum tensile strain of LO45 and LO65 increased by 16.39% and 25.28% compared to that of LO40 and LO60, respectively. The high- and low-temperature performances of the lignin–waste engine oil-modified asphalt LO65 was higher than that of the control asphalt. The dynamic stability had a good linear relationship with viscosity, the rutting factor of the unaged at 58 °C, and the rutting factor of the aged at 58 °C, while the maximum tensile strain had a good linear relationship with m-value at −18 °C. This research provides a theoretical basis for the further applications of lignin–waste engine oil-modified asphalt.

Monolithic Al2O3-SiO2 composite aerogels were synthesized by using inexpensive aluminum chloride hexahydrate (AlCl3·6H2O) and tetraethyl orthosilicate (TEOS). By adjusting the molar ratio of Al and Si, the best ratio of high-temperature resistance was found. The resultant aerogels (Al:Si = 9:1) exhibit high thermal performance, which can be identified by the low linear shrinkage of 5% and high specific surface area (SSA) of 283 m2/g at 1200 °C. Alumina in these aerogels mainly exists in the boehmite phase and gradually transforms into the θ-Al2O3 phase in the process of heating to 1200 °C. No α-Al2O3 is detected in the heating process. These Al2O3-SiO2 composite aerogels are derived from a simple, low-priced and safe method. With their high thermal performance, these aerogels will have a wide application in high-temperature field.

This study investigates the mechanical properties and microstructure of basalt fiber (BF) and nanoalumina (NA)-modified ultra-high-performance concrete with recycled aggregates (UHPC-RA) under high-temperature conditions. The effects of different replacement rates of recycled aggregates (RAs), BF content, and NA content on the compressive strength, splitting tensile strength, and elastic modulus were evaluated at ambient temperatures and after exposure to 200 °C, 400 °C, 600 °C, and 800 °C. The results show that mechanical properties decrease with temperature rise, but specimens containing BF exhibited improved crack resistance and better high-temperature integrity. The incorporation of NA enhanced the thermal stability and heat resistance of the concrete. Digital image correlation (DIC) was used to monitor real-time surface deformation, and scanning electron microscopy (SEM) analysis revealed improved microstructure with reduced porosity and cracks. This study demonstrates that the combination of BF and NA significantly enhances the high-temperature performance of UHPC-RA, which holds promising potential for applications in environments subjected to elevated temperatures.

To study the high-temperature mechanical properties of potassium magnesium phosphate cement mortar and the high-temperature resistance of its laminates. Potassium magnesium phosphate cement (MKPC) was prepared by using heavy-burning magnesium oxide and potassium dihydrogen phosphate as the main raw materials, borax as the retarder, and compounded with a certain amount of fly ash and silica fume. The effect of the mass ratio of magnesium to phosphorus (M:P), compounded fly ash and silica fume on the setting time and mechanical properties of MKPC was investigated. Furthermore, based on the better M:P, the compressive strength of MKPC mortar was studied after 3 h of constant temperature at 400 °C, 600 °C, and 800 °C, and the effect of fly ash and silica fume on the high-temperature resistance of MKPC was analyzed. The high-temperature resistance of MKPC was further evaluated by analyzing the temperature variation of potassium magnesium phosphate cement laminate during a constant temperature of 650 °C for 3 h. The results showed that the mechanical properties of potassium magnesium phosphate cement were influenced by different raw material ratios, and the mechanical properties of potassium magnesium phosphate cement were optimal when M:P was 2:1, fly ash was 5% and silica fume was 15%. The internal temperature of MKPC laminate increased slowly with time, and its high-temperature resistance was better.

Bio-oils are thought to be potentials for petroleum asphalt binders used in asphalt pavement because of the renewability and environmental friendliness. The aim of this study is to investigate the performances of asphalt binders modified by bio-oils generated from waste wood resources. Three types of bio-oils generated from wood waste resources are used in this study: the original bio-oil (OB), de-watered bio-oil (DWB) and polymer modified bio-oil (PMB). OB, DWB and PMB were added into the base asphalt PG 58-28 at 5% and 10% by weight. The rotational viscometer (RV), dynamic shear rheometer (DSR), rolling thin film oven (RTFO), pressure aging vessel (PAV) and bending beam rheometer (BBR) were conducted to evaluate the rheological properties of bio-oil modified asphalt binders. The Superpave(TM) binder specification was used to evaluate the performances of bio-oil modified asphalt binders. The test results show that the addition of bio-oil can lower the mixing temperature of asphalt mixtures while improve the high temperature performance of asphalt binders. However, the medium and low temperature performances were sacrificed. Comparison among the three types of bio-oil modified asphalt binders showed that PMB modified asphalt binders had the highest stiffness, followed by the DWB and OB modified binders. The OB had the lowest effect on the base asphalt binder compared to other two types of bio-oils. [PUBLICATION ABSTRACT]

The demand for bituminous materials is continuously growing; crude oil-based asphalt binders are non-renewable, and are facing rapid depletion. With the increase of petroleum-based asphalt prices, seeking an alternative, renewable material such as bio-asphalt has become a hot research topic. However, shortcomings in this research area have been identified, notably concerning the high-temperature performance of bio-asphalt at present. This research aims to comprehensively apply conventional tests to, and study the rheological behavior of, the high-temperature performances of bio-asphalt binders, i.e., by temperature and frequency sweeps, using a dynamic shear rheometer (DSR). It will also assess the chemical functional groups of specimens prepared by different aging conditions. Fifty penetration grade base asphalt binder (50#), bio-oil modified asphalt binders with 0%, 5%, 10%, and 30% bio-oil contents by mass, and bio-oil modified asphalt binder with combinations of 5% bio-oil-1% SBS, and 10% bio-oil-1% SBS were used in this study. The conventional performance of bio-asphalt binders was tested using penetration, ductility, and softening point, before and after short-term aging conditioning. The temperature sweep and frequency sweep of bio-asphalt under different bio-oil contents were carried out via DSR. Two-logarithmic equations of rutting factor and temperature were established, and the temperature sensitivity of bio-asphalt was analyzed. The master curves of virgin asphalt and bio-asphalt were constructed at 64 °C. The results indicate that the incorporation of bio-oil reduced the anti-rutting performance of asphalt, and the bio-oil content had a significant effect on the mass loss of the bio-asphalt binder. The performance of bio-oil modified asphalt binders using 5% bio-oil, 5% bio-oil-1% SBS, and 10% bio-oil-1% SBS, could meet the requirements of 50# grade asphalt. The temperature sensitivity of bio-asphalt did not show obvious change before and after short-term aging, whereas the temperature sensitivity of bio-asphalt with 5% bio-oil was relatively small. With an increase in temperature, the phase angle increased gradually. In contrast, the storage modulus, loss modulus, and complex modulus decreased progressively. The complex modulus and rutting factor of bio-asphalt with 5% bio-oil steadily increased with the increase in testing frequency. Otherwise, chemical reactions were detected in the 50# base asphalt modified with the bio-oil.

Asphalt binder comprises four main fractions—asphaltenes (A), saturates (S), aromatics (A), and resins (R)—referred to as “SARA”. Asphaltenes plays an important role in determining the linear viscoelastic behavior of asphalt binders. In this research, asphaltenes are added as a distinct modifier to improve the performance properties of asphalt binder. The modified binders are aged using a rolling thin film oven. A dynamic shear rheometer is then used to measure the rheological properties of the binders at high temperatures. Changes in the chemical composition of the modified binders are also studied through the determination of SARA fractions, using precipitation and gravity-driven chromatography methods. The rheological results show that asphaltenes improve the stiffness and elasticity of asphalt binder. It is also shown that the addition of asphaltenes raises the high Performance grade (PG) temperature of the asphalt binder, with every 6% of asphaltenes added resulting in a one-interval increase in high PG temperature grade. SARA analysis shows that the increase in polar fraction content due to the addition of asphaltenes causes the stiffness, elasticity, and viscosity of asphalt binders to increase. The results indicate that asphaltenes are an effective yet inexpensive additive to improve asphalt binder properties at high temperatures.

Ultra-high-performance concrete (UHPC) is considered one of the future building materials due to its excellent performance. UHPC with good thermal conductivity has potential high-value applications in large-scale bridges and nuclear facilities. As a by-product of the coal gasification process, coal gasification slag (CGS) can replace sand in traditional UHPC. In this paper, based on the preparation of UHPC by CGS, silicon carbide (SiC) was added to improve the thermal conductivity of specimens. The application of CGS and SiC as alternatives to quartz sand with varying mix ratios in UHPC was studied. The impact of the substitution ratios of CGS and SiC on fluidity, mechanical properties, and thermal performance was analyzed. The compressive strength and splitting tensile strength of five different kinds of specimens were tested at 7 d, 14 d, and 28 d. The compressive strength and mass loss rate of specimens with five different ratios were also determined under five different temperature conditions (110 °C, 200 °C, 300 °C, 400 °C, and 500 °C). The results show that the maximum compressive strength of 28 d can reach 159.5 MPa and the splitting strength is 15.30 MPa. The addition of SiC can improve the thermal conductivity and thermal stability of concrete. The compressive strength of all specimens is improved after high-temperature treatment. When substitution rate of SiC reaches 100%, the compressive strength of the specimens is up to 182.2 MPa. With the increase in temperature, the concrete burst phenomenon occurs above 300 °C. It is observed that the high-temperature burst resistance of the specimens with low strength is better than that of the specimens with high strength. Two specimens were scanned with Industrial Computerized Tomography (ICT) and the microstructures of the specimens were compared. It was found that the samples with higher SiC substitution rates had more minor total pore defects and larger pores.