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In order to obtain films with better mechanical properties and fracture toughness, the (TiAlCrZrNb)- Six-N (x=0, 4%, 8%, 12% and 16%) high entropy ceramic nanocomposite films with different Si contents were deposited on Si substrate by magnetron sputtering technology. The effects of Si doping on the microstructure, mechanical properties! and fracture toughness of the films were investigated by X-ray diffractometry, scanning electron microscopy, high-resolution transmission electron microscopy and Nano indentation apparatus. The results show that the mechanical properties and fracture toughness of the films increase first and then decrease with the addition of Si element, which can be attributed to the formation of nanocomposite structures. When Si content is 4%, (TiAlCrZrNb)-Six-N film has the best comprehensive mechanical properties, and Us maximum hardness and elastic modulus are 22.7 GPa and 192.0 GPa, respectively. In this case, the fracture toughness reaches the best, and the radial crack length C as 6.760 µm, The K1C was 1.77 MPa • m1/2. [ABSTRACT FROM AUTHOR]

ZnMn2O4 electrode materials were prepared by directly roasting mixed liquid with sucrose as the soft template. The influences of the amounts of sucrose on the structure, morphology and lithium storage properties of the synthesized ZnMn2O4 electrode materials were studied by XRI). FESEM, and electrochemical performance tests. When the molar ratio of Zn2+ to sucrose in the raw materials was 1:1.5. the prepared ZnMn2O4 sample showed a mixed morphology of irregular particles and nano-sheets. and exhibited the best lithium storage performance. The reversible capacity could reach 575 mAh/g after 200 cycles at 0.5 A/g current density. E-ven at the high current density of 5 A/g. it still delivered a reversible capacity of 295 mAh/g. The electrochemical reaction kinetic analysis showed that the ZMO-1.5 electrode had the lowest electrochemical reaction resistance and the highest lithium ion diffusion coefficient. This study was expected to provide guidance and theoretical reference for the facile and low-cost preparation of high performance ZnMn2O4 electrode materials. [ABSTRACT FROM AUTHOR]

The bias-graded TiAIN coating was successfully deposited on Ti6AMV alloy substrates using filtered cathodic vacuum arc (FCVA) technology with the bias-graded deposition method. The high-temperature oxidation performance and high-temperature particle erosion resistance of the coating were evaluated. The changes of surface morphology, composition, phase structure, and erosion damage characteristics of the coating before and after the evaluation were tested and characterized. The results showed that after high-temperature oxidation at 400 °C, the surface color of the bias-graded TiAIN coating deepened and remained intact and smooth without significant damage. The oxygen atom fraction on the surface of the bias coating is 20.9% and the mass increase is 0.81 /.ig/mm2. The structure of the bias-graded coating is more dense, inhibiting the inward expansion of oxygen elements, and has better antioxidant performance than bias-50 TiAIN coating. Under high temperature particle erosion conditions at 400 °C, the erosion rates of bias-graded TiAIN coatings at 30° and 90° erosion angles are 0.26 mg/g and 0.24 mg/g, respectively, which are lower than those of bias-50 TiAIN coatings, exhibiting better resistance to high-temperature particle erosion. At 400 °C, there is no significant oxidation damage to the titanium alloy substrate and TiAIN coating, and high-temperature particle erosion damage is the dominant mechanism of erosion. [ABSTRACT FROM AUTHOR]

In order to explore the influence of the thickness of Ni-P transition layer on the preparation of Ni-P-PTFE coating on stainless steel surface. Ni /N-P /Ni-P-PTFE three-layers structure gradient coating was prepared on stainless steel by electroplating combined with electroless plating. Scanning electron microscopy (SEM), X-ray diffraction (XRD), nano indentation, friction and wear tester, scratch tester and contact angle tester were used to characterize and test the microstructure, mechanical properties, adhesion and anti-adhesion property of the gradient coating. The results showed that, with the increased of N-P transition layer deposition time, the transition layer gradually thickened, the PTFE content in N-P-PTFE first decreased and then increased, the hardness and adhesion of N-PTFE coating first increased and then decreased. The maximum values of hardness and adhesion reach to 4.18 GPa and 13.49 N respectively when the N-P deposition time was 20 min. When the N-P deposition time was 25 min,the friction coefficient reached the minimum value of 0.17, and the contact angle between the surface of Ni-P-PTFE coating with water-based and oil-based liquid reached the maximum value of 101.1° and 60.06° respectively. At this time, the Ni-P-PTFE coating showed excellent adhesion resistance. [ABSTRACT FROM AUTHOR]

In this study, α-TCP was added into α-CSH with a ratio of 0, 5%, 10%, 15%, 20% and 25%, respectively. The solid material was combined with four kinds of prepared curing liquid, which were 0.9% NaCl solution, 2.5% Na2HPO4 solution, 7% citric acid solution and a mixture solution of 2.5% Na2HPO4 and 7% citric acid. The regulatory properties of α-CSH/α-TCP were studied by changing factors. The composite material was observed by scanning electron microscopy and X-ray diffraction, besides, the tests of setting time, mechanical properties and degradation performance were done. The effect of the change of α-TCP content on the properties of bone cement based on α-CSH was explored. Furthermore, the influence of the solidifying liquid on the properties of α-CSH/α-TCP cement was discussed when the content of α-CSH and α-TCP was constant. The results showed that the degradation performance of α-CSH/α-TCP was improved compared to pure α-CSH-based bone cement after adding α-TCP with an average particle diameter of 0.21 μm to calcium sulphate-based bone cement. With the increase of α-TCP content, the curing time was prolonged, and the mechanical property was gradually weakened. When the content of α-TCP was 15%, the addition of Na2HPO4 and CA could prolong the setting time of α-CSH/α-TCP, but the compressive strength of the composite with Na2HPO4 as the solidifying liquid was significantly higher than that of the composite materials of α-CSH/α-TCP and other solidifying liquids. The addition of α-TCP, as well as different curing liquids could adjust the mechanical properties, setting time and degradation rate of the composite bone cement to a certain extent, and provide experimental basis for the clinical application of bone repair materials. [ABSTRACT FROM AUTHOR]

In this paper, attapulgite microspheres were prepared by spray drying method and calcination subsequently. The effects of calcining temperature, microsphere dosage, contact time and concentration of dye on the adsorption properties of malachite green were investigated systematically. Results show that the fibrous and fold microstructure could be seen on the surface of the porous microspheres, and was mainly composed of palygorskite. The adsorption capacity of malachite green for microspheres increased firstly (500-700 °C) and then declined (800-1 000 °C ) with the calcination temperature increasing. The adsorption capacity and removal efficiency of malachite green for microspheres treated after 600 °C was 95.45 rng/g and 95.5%, respectively. The ad- sorption capacity of malachite green increased with the amount of microspheres and original concentration of the dye increasing, and the adsorption process could be described by the pseudo-second-order kinetic model. [ABSTRACT FROM AUTHOR]