Sangsun Yang

The Effect of Binder Content for the Pore Properties of Fe Foam Fabricated by Slurry Coating Process

Abstract Fe foam with above 90% porosity and 2 millimeter pore size was successfully fabricated by a slurry coat-ing process. In this study, the binder contents were controlled to produce the Fe foam with different pore size, strutthickness and porosity. Firstly, the slurry was prepared by uniform mixing with Fe powders, distilled water and poly-vinyl alcohol(PVA) as initial materials. After slurry coating on the polyurethane(PU) foam the sample was dried at80 o C. The PVA and PU foams were then removed by heating at 700C for 3 hours. The debinded samples were sub-sequently sintered at 1250 o C with holding time of 3 hours under hydrogen atmosphere. The three dimensional geome-tries of the obtained Fe foams with open cell structure were investigated using X-ray micro CT(computed tomography)as well as the pore morphology, size and phase.Keywords: Metal foam, Slurry coating, Sintering, Porosity, Micro-CT ······························································································································· ·································································································

Fabrication of Fecralloy Foil Coated by Fecralloy Nanoparticles Using Electrospray Processing

Fecralloy is the promising materials for high temperature exhaust filtering system due to the excellent its oxidation resistance property. In this research, Fecralloy nanoparticles coated Fecralloy thin foil was prepared by a single nozzle electrospray system in order to increase surface area of Fecralloy foil. Fecralloy nanoparticles were fabricated by electrical wire explosion method in ethanol using Fecralloy wires as a source material. Electrospray modes with applied D.C voltages to Fecralloy colloidal solution were investigated to make a stable cone-jet mode. Coated layers with and without additional heat treatment were observed by FE-SEM (field emission-scanning electron microscope) and tape test for evaluating their adhesion to substrate were performed as well.

Microstructure and mechanical behavior of low-melting point Bi-Sn-In solder joints

AbstractTernary Bi-31.5Sn-25.0In solder has been proposed and studied for application in temperature-sensitive electronic components. In a Bi-31.5Sn- 25.0In solder joint, In was detected in an intermetallic compound (IMC) layer formed at the solder/Cu substrate interface with a thickness of 4.8 μm. The microstructure of the bulk solder consisted of Sn-rich phases distributed in Bi-rich phases with dispersion of In in both phases. Meanwhile, the nanomechanical properties of the Bi-31.5Sn-25.0In solder showed great strain rate sensitivity. To be specific, hardness increased from 9.91 MPa to 56.84 MPa as the strain rate increased in the range of (0.0005-0.125) s−1. The strain-rate sensitivity exponent (m) was found to be 0.28, indicating that the excellent ductility was shown for the solder tested under the present conditions.

Influence of Particle Size Distribution on Green and Sintered Properties of Fe-Cr-Mo Prealloy Powder

【The effect of particle size distribution on green and sintered properties of Fe-Cr-Mo prealloy powder was investigated in this study. For the study, prealloyed Fe-Cr-Mo powders with different particle sizes were mixed as various ratios and cold compacted at various pressure and sintered at

Fabrication and Pore Characteristics of Cu Foam by Slurry Coating Process

1250^{\circ}C

Investigation on the Sintering Behavior and Mechanical Properties of Al-Zn-Mg Alloy Powders Mixed with Al-Si-SiC Composite Powders

for 30 min,

The Effect of Fe and Fe 2 O 3 Powder Mixing Ratios on the Pore Properties of Fe Foam Fabricated by a Slurry Coating Process

90%N_2+10%H_2

Preparation of Metal Injection Molded Dental Components using Spheroidized Ti Powders by Plasma Process

atmosphere in the continuous sintering furnace. The results shows that the powders with large particle size distribution have high compressibility and low ejection force. However the green strength are much less than those with small particle size distribution. Tensile prperties of the sintered specimes with large particles size also have high strength and elongation.】

Laser melting characterization for H13-steel 3D printing

Metallic porous materials have many interesting combinations of physical and geometrical properties with very low specific weight or high gas permeability. In this study, highly porous Cu foam is successfully fabricated by a slurry coating process. The Cu foam is fabricated specifically by changing the coating amount and the type of polyurethane foam used as a template. The processing parameters and pore characteristics are observed to identify the key parameters of the slurry coating process and the optimized morphological properties of the Cu foam. The pore characteristics of Cu foam are investigated by scanning electron micrographs and micro-CT analyzer, and air permeability of the Cu foam is measured by capillary flow porometer. We confirmed that the characteristics of Cu foam can be easily controlled in the slurry coating process by changing the microstructure, porosity, pore size, strut thickness, and the cell size. It can be considered that the fabricated Cu foams show tremendous promise for industrial application.

Microstructure and High Temperature Oxidation Behaviors of Fe-Ni Alloys by Spark Plasma Sintering

【Al-Si-SiC composite powders with intra-granular SiC particles were prepared by a gas atomization process. The composite powders were mixed with Al-Zn-Mg alloy powders as a function of weight percent. Those mixture powders were compacted with the pressure of 700 MPa and then sintered at the temperature of