Abstract
We report on the phase transition behavior and thermoelectric transport properties of Zn-doped Cu₂Se. Cu₂Se is comprised of nontoxic, low-cost and abundant elements, and has been attracting attention because of its very high thermoelectric performance, ZT, at high temperatures. Many studies have reported enhanced ZT in impurity doped Cu₂Se, however,..... More

Abstract
Tungsten carbides are quite attractive for their superior properties, e.g., high melting point, high hardness, high thermal and electrical conductivities, and relatively high chemical stability. Tungsten carbides with a binder metal, for example Co or Ni, are mainly used to produce cutting tools, nozzles and molds in the composite form...... More

Abstract
We report the thermoelectric transport properties of n-type Bi₂Te_2.7Se_0.3 compounds prepared by oxide-reduction process. The oxide-reduction process is a recently developed method that can synthesize Bi2Te3-based compounds using only oxide starting materials, which is advantageous in terms of the diversity of the starting materials and cost efficiency. In this study,..... More

Abstract
4YSZ is generally used in fuel cells, oxygen sensors, hip and knee joint replacements and thermal barriers because of it excellent properties, including low density, high biocompatibility, good resistance against corrosion, hard phase and high melting point, and high ionic conductivity. However, 4YSZ with large grain has low resistance to..... More

Abstract
Al₂O₃ has a high Young’s modulus (380 GPa), a low density (3.98 g· cm^-3), good high-temperature mechanical properties, biocompatibility and excellent oxidation resistance. Al₂O₃ has been used for automotive, aerospace, bio-materials and various industrial applications. Despite its various merits, the low fracture toughness of the material below the brittle-ductile transition..... More

Abstract
We employed spark plasma sintering (SPS) in the presence of sintering aids to fabricate high-quality Ho³⁺,Yb³⁺-co-doped Y₂O₃ transparent ceramics suitable for use as a laser gain medium, and analyzed their microstructure and optical properties. Ho³⁺,Yb³⁺-co-doped Y₂O₃ transparent ceramics with different contents of Yb³⁺ were fabricated by SPS and exhibited high..... More

Abstract
Aluminum nitride (AlN) has several attractive properties including high thermal conductivity, excellent electrical insulation, a thermal expansion coefficient close to that of Si and low density. Accordingly, it is considered a promising packing material and substrate for high power integrated circuits. However, its low fracture toughness at room temperature limits..... More

Abstract
In this study, Binderless-WC hard materials were fabricated using the pulsed current activated sintering (PCAS) process for a Friction Stir Welding tool and difficult-to-cut tool application. Tungsten carbide (WC) hard materials are used in various industries and possess a superior hardness compared to other hard materials. They have particularly high..... More

Abstract
Both the mechanical properties and probability distribution of liquid phase sintered SiC (LPS-SiC) materials were investigated, based on a detailed analysis of their microstructures. In particular, the effect of the starting sizes of SiC particles on the characterization of LPS-SiC materials was evaluated. LPS-SiC materials were fabricated with a constant..... More

Abstract
In spite of the many attractive properties of (W,Ti)C, its low fracture toughness limits its wide application. To improve the fracture toughness generally a second phase is added to fabricate a nanostructured composite. In this regard, graphene was considered as the reinforcing agent of (W,Ti)C. (W,Ti)C-graphene composites that were sintered..... More

Abstract
Thermoelectric energy conversion has attracted much attention as an efficient and environment-friendly energy technology. Thermoelectric energy conversion performance is directly influenced by the figure of merit (ZT) of the thermoelectric material, however, most known thermoelectric materials with high ZT contain toxic and/or scarce elements. Herein, we report the thermoelectric properties..... More

Abstract
Titanium nitride (TiN) has been used extensively in coating materials and cutting tools because of its attractive properties, which include low density, high melting point, high hardness and thermodynamic stability. However, like many ceramic materials, its low fracture toughness limits wide industrial application. The methods generally utilized to improve its..... More

Abstract
To fabricate a film with the highest electrical conductivity through liquid-phase reaction sintering below 200 °C using composite pastes containing both Sn-58Bi and Cu particles as a filler material, the effects of process parameters, such as the mixing ratio of the fillers, reaction temperature, and reaction time, were evaluated and..... More

Abstract
In the iron ore sintering process, a thermal imbalance can occur in the sinter feed bed which degrades the quality of the sintered ores. In order to solve this thermal imbalance, it is necessary to control the sizes of the sintering feed charging through the chute by designing an appropriate..... More

Abstract
A polycrystalline diamond compact (PDC) is a two-stage sintered body manufactured by placing diamond powders on a WC-Co hard material and then applying the high pressure high temperature (HPHT) sintering process. This study investigated the microstructure and wear properties of the PDC depending on initial diamond particle size. Three different..... More

Abstract
In this study, planetary ball milled WC-5 wt%Co powders were sintered using the pulsed current activated sintering (PCAS) process. With this process, fully densified hard materials were obtained in a shorter time than conventional processes such as a HP and HIP. The particle sizes of the planetary ball milled WC..... More

Abstract
In this study, Al alloy targets were fabricated using the powder metallurgy (pulsed current activated sintering, PCAS) process for metal PVD coating target applications. Powders were prepared from Al, Si and Cu ingots for sintering Al alloy compacts using the gas atomizing process. To fabricate the gas atomized Al alloy..... More

Abstract
Since their development in the 1970s ZrO₂ ceramics have been shown to be promising alternative materials for total hip arthroplasty (THA) and total knee arthroplasty (TKA). However, ZrO₂ is so brittle that in vivo failure can result from fracture of the ceramic femoral head and fracture of the ceramic acetabular..... More

Abstract
Despite of many attractive properties of TiN, the current concern about the TiN focuses on its low fracture toughness below the ductile-brittle transition temperature. To improve its mechanical properties, the approach generally utilized has been the addition of a second phase to form composites and to make nanostructured materials. In..... More

Abstract
Despite of the many attractive properties of TiO₂, its low fracture toughness limits many industrial applications. To improve its fracture toughness, the approach commonly utilized has been the addition of a second phase, to form composites, and to make nanostructured composites. In this regard, highly dense nanostructured TiO₂ and TiO₂-graphene..... More

Abstract
The aim of this study is to establish an optimized hot-press sintering condition for aluminum matrix composites (AMCs) by analyzing their sintered microstructure and mechanical properties. The fabricated AMCs in this study consisted of a blend of commercial Ecka Alumix 431 powder, and Al-Si/SiC_p powder manufactured by gas atomizer (Al-Si/SiC_p)...... More

Abstract
The low mechanical properties of SiC limit its wide application despite many attractive properties. To improve the mechanical properties, a second phase has been generally added to make a nanostructured composite. In this respect, graphene was evaluated as the reinforcing agent of SiC. SiC-graphene composites were sintered within 2 min..... More

Abstract
CoTi and ZrO₂ nanopowders were mechanochemically synthesized from CoTiO₃ and Zr powders according to the reaction (2CoTiO₃ + 3Zr → 2CoTi + 3ZrO₂). The milled powders were then consolidated by pulsed current-activated sintering within two minutes under an applied pressure of 80MPa. The average hardness and fracture toughness of the..... More

Material Analysis & Characterization

Abstract
In order to strengthen the structure of the glass and ultimately improve its water resistance, P₂O₅–ZnO–Bi₂O₃ was doped with Fe₂O₃, which generated Fe ions in the phosphate-based glass. These ions constitute (P₂O₇)⁻⁴ groups within the glass network. Structural analysis using Fourier transfer infrared spectroscopy indicated that P-O-P and Bi-O-P bonds..... More

Powder Metallurgy

Abstract
TiC-Co or TiC-Ni hard materials have been used for cutting tools. However, the high cost and the low hardness of Ni or Co, and the low corrosion resistance of the TiC-Ni and TiC-Co cermets have generated interest in recent years in using them as alternative binder phases. In this study,..... More