Abstract
Ni-Cr-Mo-V steel alloys for high-speed railway brake discs were prepared to investigate the effect of alloying element contents on the microstructure and mechanical properties. The Cr, Mo, Mn alloying elements were incorporated into the steel alloys, which contained low carbon content in the range 0.16 wt.% ~ 0.21 wt.% to..... More

Abstract
WC-Co cemented carbide has excellent mechanical properties and is widely used in many industrial applications including cold forging die and cutting tools. WC-Co cemented carbide is manufactured by liquid phase sintering (LPS), and a new sintering process for densification has been developed. In this study, cylindrical rod shaped tensile and..... More

Abstract
An ultrasonic nanocrystal surface modification (UNSM) technique was applied to a 1-mm thick AZ31 magnesium sheet. UNSM is a relatively new surface modification technique in which a hard, hemispherical tip (2.38 mm in diameter) strikes the surface at an ultrasonic frequency to induce plastically deformed gradient microstructures and deep compressive..... More

Abstract
Al 7075 alloy was manufactured using the twin-roll strip casting (TRC) process, and the mechanical and wear properties of the fabricated TRC process were investigated. To compare the properties of the alloy manufactured by TRC, another Al 7075 alloy was fabricated by conventional direct chill (DC) casting as a comparative..... More

Abstract
In this study, we constructed a deep convolutional generative adversarial network (DCGAN) to generate the microstructural images that imitate the real microstructures of binary Al-Si cast alloys. We prepared four combinations of alloys, Al-6wt%Si, Al-9wt%Si, Al-12wt%Si and Al-15wt%Si for machine learning. DCGAN is composed of a generator and a discriminator...... More

Abstract
One-dimensional Al and Al₂O₃ nano/microstructures were fabricated via thermal oxidation of Al and SnO₂ powder mixtures at temperatures below the melting point of Al (660 oC). Furthermore, the synthesis process was carried out in air at atmospheric pressure, which made the process very simple and easy. Sn metal particles with..... More

Abstract
Solid solutions and composites of a mixture of (K_0.5Na_0.5)NbO₃ (KNN) and SrTiO₃ (ST) were respectively synthesized by different process routes using a conventional solid state reaction. All starting materials were mixed simultaneously and calcined at 800 ^oC for 4 h to obtain the solid solutions of KNN-ST. Meanwhile, the composites..... More

Abstract
The metallurgical aspects of weld cracking in Ni-based superalloys remain relatively unexplored in existing research. The present study performed comprehensive metallurgical and manufactural investigations into the weldability of an Ni-based superalloy, CM247LC, from the viewpoint of the liquation cracking behavior and its susceptibility. Metallurgical solutions to suppress the liquation-cracking susceptibility..... More

Abstract
We attempted to classify the microstructural images of spheroidal graphite cast iron and grey cast iron using a convolutional neural network (CNN) model. The CNN comprised four combinations of convolution and pooling layers followed by two fully-connected layers. Numerous microscopic images of each cast iron were prepared to train and..... More

Abstract
The effect of tailored microstructures in 0.5 wt% CaO added AZ31 on tensile, high-cycle fatigue, and fatigue crack growth properties was examined. By adding CaO, the average grain size (AGS) was significantly reduced from 4.25±2.32 μm (conventional AZ31) to 2.42±1.60 μm (CaO-AZ31). The fineprecipitates of CaO-AZ31 were more evenly distributed..... More

Abstract
W-containing Ti-6Al-4V alloys (W=0, 1, and 5 wt%) were fabricated by the powder injection molding process, and the corresponding effects of tungsten content on the mechanical properties and microstructure of the alloys were investigated. The alloy powders were sintered at 1200 °C and then hot-isostatically-pressed at 900 °C. The fabricated..... More

Abstract
The powder microstructure and sintering behavior of W prepared by ultrasonic spray pyrolysis and spark plasma sintering were investigated. Fine-grained W powders were synthesized by ultrasonic spray pyrolysis using an ammonium metatungstate hydrate solution and hydrogen reduction. The XRD analysis of the powder, pyrolyzed below 600 ^oC, showed tungsten oxide..... More

Abstract
ZnO nano/microstructures were grown via a simple thermal evaporation process in air at atmospheric pressure. Mixtures of ZnS and carbon powders were used as the sources. The effects of growth temperature and mass ratio of carbon powder to ZnS on the morphologies and luminescence properties of the ZnO nano/microstructures were..... More

Abstract
Cemented carbide is a kind of composite material in which fine particles of carbide are embedded into the matrix of a binder metal. It has a long service life because of its superior mechanical properties. In this study, the overall tensile behavior of a cemented carbide, WC-Co, was investigated by..... More

Abstract
Nanocrystalline Fe-Si-B-Nb-Cu Finemet alloys show low saturation magnetic flux density compared to amorphous Fe-Si-B alloys. In the Fe-Si-B-Cu base amorphous alloys, Cu atoms form clusters which act as heterogeneous nucleation sites for α-Fe crystals. The addition of Ca element atoms, distributed along grain boundaries, helps inhibit grain growth and increase..... More

Abstract
Fe-Mn-Si based shape memory alloy is a new functional material that can be used to apply prestress to civil and structural components such as concrete structures. In this study, the effects of alloying elements Ni, C and Ti on the mechanical and shape memory properties of the alloy were investigated..... More

Abstract
In this study, consolidated WC-Fe compacts as a function of Fe contents were fabricated by a spark plasma sintering method, following the mixed by the ball-milled powder. Fe among the metallic binders was added to WC enhance not only the driving force of sintering process but also suppressing the grain..... More

Abstract
The subject of this study was a bronze sword excavated from the early Iron Age area of Sinpung site in Wanju. SEM-EDS, FE-EPMA and Raman Micro-Spectroscopy analysis methods were applied to investigate the manufacturing techniques and corrosion characteristics. The results of the analysis indicated a casting structure composed of both..... More

Abstract
The microstructure and mechanical properties of a newly developed, β-phase containing TiAl alloy have been studied through hot working and post heat treatment to enhance room temperature ductility and strength. The controlled microstructures hadthree types of structure, fully lamellar, nearly lamellar and duplex, and were produced by cyclic heat-treatment in..... More

Abstract
The powder-alloyed metallic sheet foam manufacturing process has the advantage of being able to control pore shape, size, and distribution more easily and homogeneously than conventional foam manufacturing processes. The effects of strain rate and tensile direction on the mechanical properties of Ni-Cr-Al superalloy foam fabricated by powder alloying method..... More

Abstract
In this study the correlation between bainitic microstructure and the low-temperature toughness of high-strength API pipeline steels was discussed in terms of crack initiation and propagation in the microstructure. Three types of API pipeline steels with different bainitic microstructures were fabricated using varying alloying elements and thermo-mechanical processing conditions, and..... More

Abstract
The effects of alloy composition on the coating structure and corrosion resistance of hot-dip Znbased alloy coated steel products were investigated. Zn-based alloy coating layers with different Al and Mg compositions were fabricated using a batch-type galvanizing simulator. Various intermetallic compounds including Zn, Zn/MgZn₂ binary eutectic, Zn/Al binary eutectoid and..... More

Abstract
The effects of heat treatment conditions on the mechanical properties and energy absorption capacity of 7003 (Al-6Zn-0.6Mg) aluminum alloy were studied. The extruded material was heat treated at various temperatures to prepare annealed or aged specimens. Tensile tests, hardness measurements, electron backscatter diffraction characterizations, and differential scanning calorimeter analyses were..... More

Abstract
The use of locally developed high performance alloys in power plants has become essential in the past ten years. Application of these alloys has been difficult because of a shortage of field demonstration testing, and the lack of lab-based test data. In this work, three types of locally developed heat..... More

Abstract
Rails are subjected to repeated stresses due to wheel-rail contact during train service. Rails under stress conditions undergo microstructural changes, and these cause degradations of the structural integrity and lifetime of rails. In this study, three different rails (newly-manufactured rail, newly-manufactured head-hardened rail, and worn (used) rail) were compared to..... More

Abstract
In this study, the effects of rolling temperature on the microstructural characteristics of a highspeed-rolled Mg alloy with a non-basal texture were investigated. To this end, commercial AZ31 alloy samples in which the basal poles of most grains were tilted at an angle of 45° from the normal direction (ND)..... More

Abstract
An explosively formed penetrator (EFP) is a kind of kinetic energy warhead that contains a metal linear structure. After exploding, the linear structure in the EFP is deformed and hits the target as a form of aero-stable long-rod penetrator. To achieve high penetration performance, Ta is commonly used as the..... More

Abstract
This study investigated the microstructure and compressive properties (at room & high temperatures) of Fe-Cr-Ni based AISI 316L alloy, manufactured by selective laser melting process. The effect of stress relieving heat treatment on the microstructure and mechanical properties also examined. Regardless of the stress relieving heat treatment, the SLMed AISI..... More

Abstract
The precipitation characteristics of hydrides in Zr-2.5% Nb pressure tube material were investigated for various hydrogen concentrations and homogenization temperatures. A surface hydride was formed using the electrolytic method and homogenized at various temperatures up to at 550 oC. The homogenization treatment was carried out at 300-550 oC over 240..... More

Abstract
In this study, we analyzed the chemical composition of Al-Si cast alloys from microstructural images, using image recognition and machine learning. Binary Al-Si alloys of Si = 1~10 wt% were cast and prepared as reference images in the dataset used for machine learning. The machine learning procedure was constructed with..... More