This review focuses on the enhancement of the magneto-optical responses in transparent Fe-oxide- and metal-doped glasses processed with an infrared femtosecond (fs) laser, with an emphasis on the author’s works. Femtosecond-laser irradiation and subsequent annealing induces the crystallization of nanoparticle composites consisting of ferrimangetic fe oxides and plasmonic metals, leading to the enhancement of magnetization, optical absorption and magnetooptical faraday rotation angles. By the use of the advantage of the fs-laser processing, novel applications, such as micro-sized optical isolator and miniaturized magnetic field sensors, can be developed.

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A study on the effect of different minerals on the pyroplastic deformation of ceramic samples was carried out in a muffle furnace. For fair comparison, samples with same chemical composition were used. The mixtures with different minerals were pressed into rectangular bar and placed on alumina supports in the furnace. The green bodies were heated up to their desired temperature and stabilized for 2 h. The solid phases in the sample which were introduced by different raw materials were found to be responsible to the pyroplastic deformation. The influence of andalusite and fly ash powders on the pyroplastic deformation was strong but slight deformation was observed if kaolin clay and calcinated kaolin clay were employed separately. It suggests that the distribution of solid particles in glassy phase plays an important role in the extent of pyroplastic deformation of porcelain sample.

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This paper presents results on the deflocculation and stabilization of Ti₃SiC₂ that are crucial for determining the quality of the ceramics after sintering in colloidal processing. Five different dispersants diammonium hydrogen citrate, citric acid, polyethyleneimine, polycarboxylic acid and ammonium polyacrylate were examined by measuring the zeta potential and performing stabilization tests and rheological measurements. The dispersant, found to exhibit the most desirable properties, was then used in the gelcasting process as a novel and attractive means of obtaining high-quality Ti₃SiC₂ materials with a complex-shape without the addition of pressure. Furthermore, the utility of a glycerol derivative as a low-toxicity, water-soluble monomer in the fabrication of Ti₃SiC₂ by gelcasting was examined. Our measurements showed that polyelectrolytes such as polyethyleneimine, polycarboxylic acid and ammonium polyacrylate have a positive effect on the deflocculation and stabilization of Ti₃SiC₂ ceramic suspensions. Nevertheless, only ammonium polyacrylate effectively stabilizes the Ti₃SiC₂ slurry in the gelcasting process. Using ammonium polyacrylate, it was possible to obtain both high solid loading of approximately 60 vol % and a low-viscosity suspension. Using a suitable monomer and dispersant, the green bodies with a high density (62% of the theoretical density) were obtained, which resulted in ceramic part with high mechanical strength. The tensile strength of the green bodies was approximately 1.5 MPa.

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ZnO micro/nanocrystals with different morphologies were synthesized through thermal evaporation of Al–Zn mixtures under air atmosphere. The Al–Zn mixtures were put into alumina crucibles and then inserted into an electric furnace. The effect of synthesis temperature and time on the morphology of ZnO crystals was investigated. At temperatures below 900°C, no ZnO crystals were synthesized. When the temperature was 1000°C, ZnO crystals with a hexagonal pillar shape were found. With the increase in the temperature from 1000 to 1100°C, the morphology of the crystals changed to wire and granular shapes. As the synthesis time increased at 1000°C, tetrapod-shaped ZnO crystals started to be formed. As a result, the synthesis temperature and time were key factors in the morphological control of ZnO crystals. Because no catalyst particles were observed at the tips of the micro/nanocrystals, it is suggested that the ZnO crystals were grown via a vapor–solid mechanism.

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We demonstrated the synthesis of hydroxy sodalite (HS) via a simple hydrothermal process using windshield waste as the source material. Acid-treated waste glass was directly used as the silicate precursor. The syntheses were conducted under various NaOH-precursor contents for 1, 12, and 24 h. The crystal structure and morphology of the HS were identified by X-ray diffraction and field-emission scanning electron microscopy. As per the results of the analyses, the HS and zeolite-A phases formed with low NaOH content, but HS was successfully synthesized in a single phase with a Na₂O:SiO₂:Al₂O₃ molar ratio of 2.2:1:1 over the course of 24 h. For uniform and high-purity HS crystals, the sizes of the particles of windshield waste were reduced via a high-energy milling process, and then we conducted the hydrothermal procedure under same conditions. Finally, uniformly sized HS crystals were produced with an average diameter of 3 µm. These optimized conditions were not only scientifically valuable to understand the formation process, but this process should also accelerate windshield-waste recycling.

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The effects of the substitution of Mn²⁺ at Mg²⁺ sites on the structural characteristics and microwave dielectric properties of (Mg_1−xMn_x)₂(Ti_0.95Sn_0.05)O₄ (x = 0.01–0.009) ceramics were investigated. Second phase of (Mg_1−xMn_x)₂(Ti_0.95Sn_0.05)O₃ was observed. The sintering characteristics of (Mg_1−xMn_x)₂(Ti_0.95Sn_0.05)O₄ ceramics are developed by the X-ray diffraction patterns and SEM observations to find the influence of sintering temperatures and Sn⁴⁺ content on the crystal structure and the grain growth. The influence Mn²⁺ content and sintering temperatures on the quality values (Q × f) and the temperature coefficient of resonant frequency (τ_f values) of (Mg_1−xMn_x)₂(Ti_0.95Sn_0.05)O₄ ceramics at microwave frequency are well developed in this study. As an optimal compose, (Mg_1−xMn_x)₂(Ti_0.95Sn_0.05)O₄ (x = 0.05) successfully demonstrated a dielectric constant of 14.21, a Q × f of 347,000 GHz and a temperature coefficient of resonent frequency value of −57.94 ppm/°C sintering at 1325°C.

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Synthesis of phase-pure forsterite (Mg₂SiO₄) is a challenging process that requires multiple steps including careful heat treatment and ball milling. In this work, the effects of temperature, time and ball milling duration in synthesizing forsterite powder were investigated. A comparison of 1000 and 1200°C heat treatment temperature with 1 min, 1, and 2 h of holding time during heat treatment was conducted. In addition, 1, 5, 7, and 10 h of milling time were selected as variables to identify optimum conditions for completion of reaction in forming pure forsterite powder. Based on the X-ray diffraction results, 1200°C heat treatment, 2 h of holding time, and 7 h of milling successfully produced single phase forsterite powders with crystallite size of 41 nm. The forsterite powder was compacted and sintered at temperatures ranging from 1200 to 1500°C. The highest hardness and fracture toughness of 7.11 GPa and 4.88 MPa m^1/2 were achieved when sintered at 1400°C, respectively. Meanwhile, the highest relative density of 91% was obtained for the sample sintered at 1500°C.

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A new lead-free piezoelectric ceramics of (1 − x)Bi_0.5Na_0.5TiO₃–xBa(Ni_1/3Nb_2/3)O₃ (BNT–BNN) (x = 0.0–0.07) have been prepared by a conventional solid reaction method. Their structures and electric properties have been investigated systematically. A pure perovskite phase can be formed in x ≤ 0.06. By the introduction of Ba(Ni_1/3Nb_2/3)O₃, the ceramics exhibit a lower coercive field E_C. Composition for x = 0.02 shows optimal piezoelectric properties, with the piezoelectric coefficient d₃₃ = 121 pC/N. Temperature dependent P(E) loops and S(E) curves of 0.98BNT–0.02BNN indicate that the phase transition from the ferroelectric to antiferroelectric takes place over a very wide temperature range from 75 to 150°C.

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Recently, porous ceramic membranes have become a subject of significant interest because of their outstanding thermal and chemical stability. To reduce the high manufacturing costs of these porous ceramic membranes, recent research has investigated the utilization of low-cost natural materials. Therefore, in this paper, we report the results of our efforts to determine whether we could utilize sodium borate as a bonding phase, and we also report the results of an attempt to prepare a pyrophyllite-diatomite composite support layer that could effectively filter the ISO 12103-1 A3 test dust while exhibiting acceptable water permeability. The pore characteristics of the specimens were studied by scanning electron micrography, mercury porosimetry, capillary flow porosimetry, and a dead-end microfiltration system with particle counters.

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The in situ synthesis and consolidation of B₄C–VB₂ eutectic composites by spark plasma sintering (SPS) is reported. The microstructure properties were determined for composites with the B₄C–VB₂ eutectic composition as functions of the VB₂ content and the VB₂–VB₂ interlamellar spacing. A change of VB₂ concentration from 45 to 48 mol.% resulted in the formation of the rod-like eutectic microstructure. Indentation fracture toughness values higher than 4 MPa·m^1/2 were identified for eutectic composites with interlamellar spacings between 0.9 and 1.2 µm. The composites obtained by SPS with a composition of 45 mol.% VB₂ exhibited a lower Vickers hardness (23–24 GPa) and higher indentation fracture toughness (up to 4.5 MPa·m^1/2) than the eutectic composites with 48 mol.% of VB₂.

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Thermal propagation and diffusion in the carbon fiber (CF)/thermoplastic (TP) model composites, which was composed of a single CF and thin TP films, were investigated as a basic research of a rapid carbon fiber reinforced thermoplastic (CFRTP) molding by microwave irradiation. In case of the CF/TP model composite with thermally-conductive matrix prepared from polypropylene (PP) and 5 vol.% hexagonal boron nitride (h-BN) powder, the thermal propagation in the matrix was enhanced till 2.3 times as compared to one with PP of the conventional matrix of 0.15 W/(m·K). Its thermal propagation agreed with the one-dimensional heat equation. Moreover, the thermally-conductive matrix led to the suppression of thermal decomposition at the interface between CF and matrix in composites.

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