Journal of the Australian Ceramic Society最新文献

The use of magnesium (Mg) and its alloys as potential materials for bone implants is gaining attention of researchers. This is due to their biocompatibility, mechanical properties, and ability to degrade in the body. Plasma Electrolytic Oxidation (PEO) is a promising surface modification technique for enhancing the performance of magnesium and its alloys in orthopedic and dental implants. It helps develop an oxide ceramic layer on the surface. This article provides an in-depth analysis of the recent advancements in PEO of magnesium and related alloys for use in bone implants. It begins by explaining the fundamental principles of PEO, including the electrochemical and plasma processes involved in forming ceramic coatings on magnesium substrates. It then describes how various factors affect the oxide layers. These include the electrolyte mixture, voltage, current density, and treatment length. It focuses on the microstructure, biocompatibility, and corrosion resistance of PEO-treated magnesium alloys. Additionally, it explains the biocompatibility and bioactivity performance of the PEO-coated magnesium alloys. This involves their interactions with biological systems, cell adhesion, proliferation, and osseointegration. The review also covers challenges and limitations of PEO. Its comprehensive analysis of PEO technique, surface characteristics, mechanical properties, corrosion behavior, and biocompatibility aspects is valuable. It's a resource for researchers, clinicians, and materials scientists creating novel, biocompatible magnesium-based materials. These materials are suitable for dental and orthopedic implants. As the field continues to evolve, further research directions and potential breakthroughs are outlined to propel the application of PEO-treated magnesium alloys in the realm of bone implants, offering patients improved medical outcomes and enhanced quality of life.

Nanocomposite containing vanadium oxide (V₂O₅) and magnetite (Fe₃O₄) doped with nickel (Ni) ion were synthesized according to the formula of Ni_0.1Fe_2.9O₄ /V₂O₅. The obtained composition was characterized by XRD, FTIR, FESEM. The FESEM micrograph shows that the existence of two different phases related to V₂O₅ and Ni-Magnetite. Moreover,the roughness parameters have values of 281, 85 and 385nm for roughness average R_a, root mean square roughness R_q, Maximum height of roughness R_T respectively. Moreover, the magnetic behavior of the sample was studied, and we found that by adding V₂O₅ to Ni dopped magnetite, the curie temperature value was lowered from 750 ^oC to 625 ^oC. The activation energy was calculated and found to be 0.22 eV and 0.08 eV for 1000 Hz and 3MHz respectively.

Spodumene glass-ceramics composed of Li₂O-Al₂O₃-SiO₂ were prepared using gold tailings (Shuangqi Mountain, Quanzhou, Fujian, China) as the raw material through a two-step crystallization method. The crystallization behavior, phase structure, and microstructure of the glass-ceramics were characterized by DSC, XRD, and SEM. The results indicate that the addition of gold tailings promoted the precipitation of the β-quartz solid solution and its transformation into β-spodumene solid solution. Dense nanoscale crystal particles have been formed in the crystallized samples, and a high content of gold tailings significantly improved the flexural strength and thermal conductivity of glass-ceramics. Simultaneously, low coefficient of thermal expansion can be obtained at higher crystallization temperatures. Overall, the sample fabricated with 45% gold tailings showed relatively excellent properties at a crystallization temperature of 850 ℃. The coefficient of thermal expansion (CTE), flexural strength, bulk density, and thermal conductivity are 2.38 × 10^− 6 K^− 1, 87.71 MPa, 2.445 kg m⁻³, and 3.574 W m^− 1K^− 1 (500 °C), respectively. This work verifies the possibility of using gold tailings as raw materials for the preparation of lithium spodumene glass-ceramics, which have potential for large-scale commercial applications.

Environmental and materials scientists are becoming more interested in catalytic materials for use in filtration and remediation of contaminated gas.. In this study, Ag/SnO₂ catalysts were adorned onto a polypropylene (PP) membrane to eliminate nitrogen oxide (NO_x) gas. The catalyst-coated membrane achieved an efficiency of 63.62% and exhibited a low generation of nitrogen dioxide (NO₂), just 2.51%. It is noteworthy that even after five cycle experiments, the Ag/SnO₂/PP catalytic membrane showed remarkable resilience, retaining a high removal efficiency of approximately 58.2%. Furthermore, the catalytic membrane demonstrated a positive trend in transforming NO_x into eco-friendly products, hence decreasing the generation of NO₂ byproducts. These encouraging findings demonstrate the Ag/SnO₂ catalysts' potential for treating contaminated gasses in the near future in catalytic membrane technologies.

Zinc-incorporated manganese ferrite in polyvinylpyrrolidone matrices was successfully synthesized via a co-precipitation method at 1000 °C. Zn²⁺ doping was found to have a notable effect on the structural properties of the sample, as evidenced by XRD results indicating a cubic FCC structure with a ferrite spinel structure. The average crystallite size was 20.61 nm, and the lattice parameters of the samples varied slightly depending on the amount of Zn²⁺ doping. It was observed that Zn²⁺ doping increases both the magnetic moment and temperature of the sample. Zn²⁺ ions possess a large magnetic moment, which interacts with the other ions in the sample, resulting in an increased overall magnetic moment and coercivity. FE-SEM microstructure revealed cauliflower morphology, multiple pores, and rough aggregates. This increased magnetic moment was reflected in a specific capacitance value of 53.518Fg⁻¹ at a scanning rate of 30mVs⁻¹. Impedance analysis reveals that the relaxation phenomenon is highly dependent on concentration and frequency. PVP-coated Zinc-incorporated manganese ferrites are of great importance in technology and science due to their high saturation magnetization and low core losses. These ferrites have been widely utilized in electronic applications, such as magnetic storage devices, sensors, and microwave devices.

The microstructure and surface properties of ceramic glaze are influenced by chemical composition, particle size distribution, glaze application conditions, and firing parameters. This study specifically focused on the influence of glaze particle size distribution on the thermal behavior, microstructure, and surface appearance of barium frit based ceramic glaze in the floor tile firing process. The investigation involved examining the impact of four distinct particle size dimensions (d50: 5.7 μm, 6.8 μm, 7.5 μm, 10.9 μm) on the glaze properties by using hot stage microscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), color and gloss measurements. The studies indicated that celsian is the dominant phase in the glaze structure. The sintering and softening temperatures of glazes decreased with the increase of milling time. A decrease in the particle size of the glaze slurry increased the whiteness index. As the average particle size (d50) of the glaze decreased, the number of crystals was also increased. The investigation results also suggested a relation between specular reflection and milling time. As the milling time extended, there was a corresponding increase in the magnitude of glossiness.

This work presents the synthesis of bioactive glass 55SiO₂– 41CaO– 4P₂O₅ (mol%) by the hydrothermal method using oleic acid as a structural-control agent. Glass samples synthesized at different oleic acid concentrations 0 M, 0.25 M, 0.5 M, and 1 M (denoted as 55 S-0 M, 55 S-0.25 M, 55 S-0.5 M, 55 S-1 M) were characterized by physic-chemical methods such as TGA-DCS, XRD, FTIR, SEM, TEM, and BET. According to the findings, glass materials in the form of amorphous and mesoporous structures can be synthesized by heating dried gel at about 700 ^oC. The formation of sharp hydroxyapatite peaks after in vitro experiment shows higher bioactivity in samples 55 S-0.25 M, and 55 S-0.5 M, which have higher porosity, and specific surface area. Furthermore, all glass samples synthesized in oleic acid demonstrate excellent biocompatibility with fibroblast cells (L-929).

Melt-quenching bioglass-ceramics with the following chemical composition have been prepared 44SLS( -)11Na₂CO₃( -)24ES( -)6P₂O₅( -)6CaF₂( -)9Al₂O₃ (wt%). The bioglass-ceramics were sintered at 650 °C, 750 °C, 850 °C, and 950 °C. The aim was to identify the optimal sintering temperature before glass crystallization. The physical properties were characterized by density and linear shrinkage. To characterize the structure properties, X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR) were utilized. The high composition of Si and Ca in soda lime silica (SLS) glass and eggshells (ES), respectively, encourage the utilization of waste materials in the production of bioglass-ceramics. The results showed that at a sintering temperature of 950 °C, the crystallization of fluorapatite was the main phase. Moreover, the high density and optimum linear shrinkage were obtained as the sintering temperature increased. Additionally, grain growth and densification took place at this temperature. The compressive strength of bioglass-ceramics is influenced by sintering temperature and the optimal compressive strength is 136.58 MPa.

The heat distribution and wear threat of the plate crystallizer used in continuous casting production are different in each area, and a single-thickness coating is unable to fulfill the requirements of all areas. To extend the service life of the crystallizer, a high hardness WC-Cr₃C₂-Ni thickness gradient wear-resistant coating was prepared on the inner wall of the crystallizer via the HVAF (High-Velocity Air Fuel) spraying technology. In cyclic thermal shock environments, the thermal shock resistance of planar coatings decreased with the thickness. The coating with a thickness of 100 μm exhibited the best thermal shock resistance, with up to 25 cycles at 800 °C thermal shock. In high-temperature wear experiments simulating actual service environments, the 300 μm coating, which owned the worst theoretical thermal shock resistance, was well bonded to the substrate and exhibited good serviceability. Comprehensive experimental results showed that the WC-Cr₃C₂-Ni coatings deposited by HVAF were stable in practical long-cycle production. The coating preparation process proposed in this paper has been applied in domestic steel mills, effectively extending the working cycle of the production line and improving economic efficiency. This study will provide a theoretical basis for the selection and preparation of surface coatings for continuous casting crystallizers and other structures in complex service environments.

This study investigated the influence of specific dopant ions strontium (Sr²⁺), zinc (Zn²⁺), silver (Ag⁺), and fluoride (F⁻) on the functionality of composite doped hydroxyapatite (CD-HA) materials. A well-known optimization technique i.e., Taguchi’s design of experiments was employed to identify the ideal dopant concentrations in HA. This approach aimed to achieve a desired dielectric constant (DC), a key electrical property, while simultaneously promoting favourable biological properties for potential tissue engineering applications. Compared to undoped HA, specific CD-HA L6 (2.5Sr-5.0Zn-2.5 F) and L9 (5.0Sr-5.0Zn-2.5Ag) compositions exhibited significantly increased dielectric constants, reaching up to 145% higher values. The finding suggest that these nutrient doped HA could be beneficial in applications where electrical stimulation play a crucial role for bone growth. Further, L6 and L9 samples demonstrated nearly double the cell proliferation rate compared to undoped HA. In addition to cell material interaction, the antibacterial activity of both undoped HA and CD-HA samples against Escherichia coli and Staphylococcus aureus bacteria was conducted successfully. Notably, the L9 (5.0Sr-5.0Zn-2.5Ag) composition displayed the strongest antibacterial effect, with the largest inhibition zone against E. coli. These aforementioned findings suggested that these bio-ceramic CD-HA compositions containing 5% Sr and Zn, along with 2.5% Ag and F can be used as the potential candidates for various biomedical applications.