Abstract
A new Ni based superalloy is considered as bucket material because of high fatigue resistance with fine grain. However a bucket is usually exposed to high temperature for a long time, so creep rupture tests were conducted to understand the microstructure evolution during creep deformation under various stresses at temperatures..... More

Abstract
The influence of ultrasonic melt treatment (UST) combined with a change in cooling rates on the microstructure and elevated temperature mechanical properties of a hypereutectic Al-18Si-4Cu-3Ni piston alloy was investigated. Microstructural observation confirmed that UST effectively refined the sizes of primary Si and intermetallic compounds (e.g. ε-Al₃Ni) while promoting their..... More

Abstract
The resistance of hydrogen induced cracking (HIC) was investigated with different microstructures of API X70MS steel. Ferrite/acicular ferrite (F/AF), deformed ferrite/acicular ferrite, ferrite/bainite (F/B) and single acicular ferrite (AF) were obtained by thermo-mechanical controlled process (TMCP) with changing rolling and cooling conditions. HIC resistance was found to be affected by..... More

Abstract
In this paper, Cu-coated graphite powders for a low thermal expansion coefficient and a high thermal conductivity are fabricated using a chemical reaction process. The Cu particles adhere to the irregular graphite powders and they homogeneously disperse in the graphite matrix. Cu-coated graphite powders are coarser at approximately 3~4 ㎛..... More

Abstract
The effect of ultrasonic melt treatment (UST) on the microstructure and mechanical properties of Al-7Si-0.35Mg (A356) casting alloys was investigated. The particular aim of this study was to analyze the mechanism involved in the strengthening of the A356 alloys when fabricated by UST. The UST had little effect on the..... More

Abstract
The effects of nitrogen content on the HAZ softening of Ti-containing high strength steels manufactured by accelerating cooling were investigated and interpreted in terms of the microstructures in the softening zone. Regardless of their content, all of the steels investigated showed a softened zone 9-10 mm wide. The minimum hardness..... More

Abstract
In this study, the effect of α and β those stabilizers on the microstructure and phase transformation of cast Ti-6wt%Al-4wt%V alloy at various solution treatment temperatures was investigated. The dependence of the transformation behavior of the β phase during the solution treatment and its dependence was determined by the partitioning..... More

Abstract
In order to study the effect of microstructural change on the tensile properties of discontinuous precipitated Al-Zn binary alloy, four different Al-Zn alloys(25, 30, 35, 45 wt% Zn) were aged at 160 ℃ for different aging times(0, 5, 15, 30, 60, 120, 360 min) after being solution treated at 400..... More

Modeling and Simulation

Abstract
Yttrium Aluminum Garnet (YAG) single crystal has received much attention as the high power solid-state laser’s key component in industrial and medical applications. Various growth methods have been proposed, and currently the induction-heating Czochralski (IHCZ) growth method is mainly used to grow YAG single crystal. Due to the intrinsic properties..... More

Abstract
In the present study, we systematically investigated the effect of entropy of mixing (ΔS_mix) on the mechanical and thermal properties of single phase FCC solid solutions with multi-principal elements. An increase in ΔS_mix led to an increase in micro-hardness and a decrease in thermal conductivity (κ) due to severe lattice..... More

Abstract
The aim of this study is to optimize the microstructure and mechanical properties of Ti-39Nb-6Zr (TNZ40) for bio-implant applications. TNZ40 was designed to have a low elastic modulus (~40 GPa) and good biocompatibility. However, the alloy shows relatively low strength compared to other titanium alloys for bio-implant. In the present..... More

Abstract
In this work, niobium (V) fluoride was selected as an additive to heighten the hydrogen sorption rates of Mg. Specimens of pure Mg, 5 wt% niobium fluoride－added Mg, and 10 wt% niobium fluoride-added Mg were prepared by planetary ball milling in hydrogen. The hydrogen sorption properties of the specimens were..... More

Abstract
In this paper, we demonstrate that the microstructure and mechanical properties in the Ti₄₀Zr₁₀Cu₃₆Pd₁₄ alloy can be tailored by controlling the cooling rate during solidification. A lower cooling rate increases the volume fraction of crystalline phase such as B2 but decreases the free volume of the glassy matrix. The increase..... More

Abstract
In this study, the effect of cold drawing and heat treatment on the microstructure of Invar36 alloy wire was investigated. Invar36 alloy wire is used as a transmission line core material, and is required to have high strength. The diameter of the Invar36 alloy wire specimens were reduced from 16..... More

Materials Analysis & Characterization

Abstract
Experimental techniques for serial sectioning and reconstruction were investigated in the three-dimensional imaging of microstructures in metallic materials. Mechanical polishing equipped with a light optical microscope and a digital image processor was used for the serial sectioning and reconstruction. Different processing conditions were investigated for three different alloys: Al-Si alloy,..... More

Casting/Solidification/Heat Treatment

Powder Metallurgy

Abstract
A tungsten coating was deposited onto a graphite substrate using the atmospheric plasma spraying (APS) technique. In order to increase the adhesion strength between the metallic tungsten(W) and graphite, a molybdenum (Mo) interlayer was pre-deposited onto the graphite surface by utilizing the APS technique. Also, after deposition of a APS-W..... More