Hyuk Chang's Home Page
Welcome to My World!
Keywords : Metal Matrix Composite / Nanophase / Small Fuel Cell (PEMFC, DMFC)
Please come in and find out what my interests are. We now can share the information more easily.
Number of Hits since Jan. 1, 1999
My Background
I was born in Seoul, Korea and am now living in a new town 'Pundang' the city adjacent to the southern part of Seoul. Married in 1987, I have two kids, a lovely daughter (age 10) and a son (age 3). After being educated locally at Inha University, I had studied abroad at the University of Utah, Salt Lake City, Utah, USA for M.S and Ph.D in the field of Metallurgical Engineering. After a couple of years of research work as a Research Associate at theUniversity of Illinois at Urbana-Champaign, Illinois, USA, I came back home and started a research job at here in Samsung Advanced Institute of Technlogy, Korea.
My Research Area
Before we go any further, the list of my publication can help you to look into my research area by clicking here.
As you have found from the above papers list, my research field can be identified as two groups (Novel metal synthesis & Electrochemical power source). However, both relates to the field of studying metal with a Materials Science background.
Metal Matrix Composite
A novel method of coating tin oxide particles with wilver by an electroless plating process were studied to produce silver-tin oxide electrical contact alloys. Those composite powders were consolidated to a fully dense compact by an optimal powder metallurgy prcess, so that alloy that has sufficient hardness and high electrical conductivity. Also Alumina particles dispersed 2024 aluminum alloys were manufactured by casting method in order to achieve superior mechanical properties even at high temperature. This ODS (Oxide dispersion strengthened) alloys have potential application for structures with need high temperature strength and light weight. The OM, SEM, TEM, XRD, EPMA, microhardness, and tensile test at elevated temepratures were applid for the anaysis in thess studies. Electrochemical analysis by utilizing Potenio-galvanostat enabled the kinetic study of electroless plating process.
EPMA of Ag-SnO2 composite (light green : metal matrix, green & blue dots : submicron size dispersed oxide)
Nanophase Metals
Nanophase metal powders in the range of 10 to 20 nm were synthesiszed by dc magnetron sputtering in an inert gas atmosphere and compacted into bulk wafers in situ. A number of methods were applied to investigate the novel methods were applied to investigate the novel characteristics utilizing microhardness and creep tests at ambinet and elevated temperatures, TEM, SEM, calorimetry, SIMS, Auger and XRD. Nanophase Cu, TiAl, Ni3Al and TiAl-TiB2 were studied. The results indicated that the deformatin of nanophase metals are dominated by grain boundary process and able to lead superplastic properties.
(a) (b)
(a) UHV Chamber with in-situ nanophase metal process at UIUC . Blue arc shown here is in the process of magnetron sputtering of TiAl target. (b) As sputtered nanophase TiAl showing 10 nm sized powers.
Rechargeable Battery
Seald nickel-zinc batteries including 180Ah-1.6V single cell, 50Ah-8V and 80Ah-6.4V module have been developed and their advanced characteristics showed the potential for EV. Application of novel compostion of active materials and electrolyte solved the classical problem of the short cycle life. Improvements of separators and electrode surface treatment were also contributed. Also involved in the studies of Ni-MH and Li battery system. Electrochemical studies of understanding the battery systems were performed.
Portable Fuel Cell
Heading to the 21st century, clean and alternative power source is required and the hydrogen enerygy is one of the candidates that can produce electriciy at high efficiency without polution. This Proton Exchange Membrane Fuel Cell(PEMFC) is studied from making elelctrode to assemble the stack. Electrochemical anaysis and materials sysntheis is now under studying. Direct Methanol Fuel Cell is under developing for the portable electronic devices since this has the advantage of short refueling time and longer operation time compared to the rechargeable batteries. More detials are coming down...........
My Current Interests
This is my current interest, which is a vehicle utilizing clean alternative energy (Hydrogen) via Fuel Cell which converts hydrogen energy to electiricity. I, currently, put 100% of my research time to develop a novel Proton Exchange Membrane Fuel Cell Stack and Direct Methanol Fuel Cell Pack that can be applied to the portable electronic deices.
Here you can refer the technology roadmap of portable fuel cell
And here're current research achivements.
100W PEM Fuel Cell Stack
40W PEM Fuel Cell Stack Operating Note PC
1W Direct Methanol Fuel Cell Pack
Links to My Favorite Sites
Another way to really get to know someone - especially someone who spends as much time on the Internet as I do - is to learn their favorite sites. Here are the web sites I go in almost once per everyday. Please find the common interests.
Anybody who needs more detail of the information or has suggestion on this web site,
This page last updated on Jan.25th of 2000