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High-entropy rare-earth aluminate (Y0.2Yb0.2Lu0.2Eu0.2Er0.2)3Al5O12 (HE-RE3Al5O12) has been considered as a promising thermal protection coating (TPC) material based on its low thermal conductivity and close thermal expansion coefficient to that of Al2O3. However, such a coating has not been experimentally prepared, and its thermal protection performance has not been evaluated. To prove the feasibility of utilizing HE-RE3Al5O12 as a TPC, HE-RE3Al5O12 coating was deposited on a nickelbased superalloy for the first time using the atmospheric plasma spraying technique. The stability, surface, and cross-sectional morphologies, as well as the fracture surface of the HE-RE3Al5O12 coating were investigated, and the thermal shock resistance was evaluated using the oxyacetylene flame test. The results show that the HE-RE3Al5O12 coating can remain intact after 50 cycles at 1200 °C for 200 s, while the edge peeling phenomenon occurs after 10 cycles at 1400 °C for 200 s. This study clearly demonstrates that HE-RE3Al5O12 coating is effective for protecting the nickel-based superalloy, and the atmospheric plasma spraying is a suitable method for preparing this kind of coatings.

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The properties of non‐oxide materials are continuously revealed, and their applications in the fields of ceramics, energy, and catalysis are increasingly extensive. Regardless of the traditional binary materials or the MAX phases, the preparation methods, which are environmentally friendly, efficient, economical, and easy to scale‐up, have always been the focus of attention. Molten salt synthesis has demonstrated unparalleled advantages in achieving non‐oxide materials. In addition, with the development of the process in molten salt synthesis, it also shows great potential in scale‐up production. In this review, the recent progress of molten salt synthesis in the preparation of binary non‐oxide and MAX phase is reviewed, as well as some novel processes. The reaction mechanisms and the influence of synthetic conditions for certain materials are discussed in detail. The paper is finalized with the discussion of the application prospect and future research trends of molten salt synthesis in non‐oxide materials.

A negative stiffness element is always employed to generate high-static–low-dynamic stiffness characteristic of the vibration isolator, reduce the resonance frequency of the isolator, and improve the vibration isolation performance under low and ultra-low frequency excitation. In this paper, a new compact negative stiffness permanent magnetic spring (NSPMS) that is composed of two axial-magnetized permanent magnetic rings is proposed. An analytical expression of magnetic negative stiffness of the NSPMS is deduced by using the Coulombian model. After analyzing the effect of air-gap width, air-gap position, height difference between the inner ring and outer ring on the negative stiffness characteristic, a design procedure is proposed to realize the negative stiffness characteristic with a global minimum linear component and uniformity stiffness near the equilibrium position. Finally, an experimental prototype is developed to validate the effectiveness of the NSPMS. The experimental results show that combining a vibration isolator with the NSPMS in parallel can lower the natural frequency and improve the isolation performance of the isolator.

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consuming dedusting device is therefore inevitable. [2] Urea rotary steel-band chilling granulation can partly alleviate the serious dust problem at the expense of the spherical appearance and moisture resistance of the particles, although a small amount of dust emission will still occur during production while unloading the products. [3] Our previous studies proposed a new dust-free large urea granulation (DLUG) process based on the super-repellency effect of the urea melt on a superhydrophobic surface. [4] A single urea melt droplet (UMD) forms a spherical shape spontaneously owing to its surface tension and easily achieves rolling-spheronization granulation after solidification. During this process, no dust is theoretically generated if no collisions occur. However, this hypothesis cannot be realized because the collisions between UMDs and urea solid particles are unavoidable if continuous production is required. Therefore, preventing UMDs from breaking into tiny particles or coalescing into oversized granules, thereby eliminating possible dust generation during a collision, is necessary for the practicality of the DLUG process. In addition, some unexpected occurrences have been observed during a lengthy operation, including surface adhesion of the urea, destroying the superhydrophobicity and resulting in a tailing of the urea granules and a decreased sphericity. Further improving UMD strengthen and decreasing the destructive effect of urea melt on superhydrophobic surface are necessary aspects for enhancing applicability of DLUG process.To overcome the above problems, liquid marble can be applied during the DLUG process. Liquid marble is obtained by covering the liquid droplet surface with non-wetting nanoscale or microscale particles as a type of "armor," [5] providing attractive properties similar to those of solid elastic granules. A high contact angle (CA) on both hydrophilic and hydrophobic surfaces is realized, [6,7] which is helpful for maintaining perfect sphericity under static conditions and exhibiting a low rolling friction under dynamic conditions. [8] Most notably, liquid marbles can endure an elastic deformation of ≈30%. Within Urea melt droplets (UMDs) spontaneously spheronize and form large urea granules after condensation on superhydrophobic surfaces without dust generation. However, they break and coalesce when colliding with each other; moreover, they adhere to the surface and form tails when rolling. These problems limit the practicality of the process using UMDs for large urea granulation directly. Urea melt marbles (UMMs) are introduced to overcome these drawbacks by enwrapping UMDs with superhydrophobic polytetrafluoroethylene (PTFE) powder, thus enhancing the elasticity and maintaining the sphericity. A premixing-melting process is developed to obtain UMMs and lower the PTFE powder consumption to half of that required in the traditional liquid marble preparation. The best determined elasticity modulus of UMMs reaches 44.9 ± 3.6 Pa, and the sphericity is 0.9992. No adhering or tailing...

In this research, an experiment was conducted by introducing superhydrophobic surface into rolling spheronization granulation. The employed superhydrophobic surface was prepared with modification of an anodized Cu mesh with silane FAS-17 and exhibited excellent uniformity, adequate stability, and broad adaptability in the granulation scenario. Completely spherical molecular sieve granules with 99.85% sphericity and 2.53 mm diameter were obtained. The compressive strength of a single granule reached 7.402 N/ea. Only negligible residual mass and slight surface abrasion were observed in the granulation process. Force analysis confirmed that the staged motion behavior of droplets caused by the interaction between the slurry and the superhydrophobic surface benefited to the formation of spherical granules. Successful application of this process for granulation of other substances confirmed its wide suitability. With the advantages of easy fabrication, high-quality granules, and low cost, rolling-spheronization granulation on superhydrophobic surfaces has great potential for scale-up applications.