• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.446-450
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• 2007

It is strongly expected that inkjet printing method will be play and important role on printable electronics such as 3D integration of embedded ceramic devices(capacitor, resistor, inductor and electrode or circuit), Si-TFT and organic TFT including display C/F, RFID, FPCB, and etc. A inkjet printing method had been center of attention to strengthen the competitiveness of flat panel display on market and to open the new world of manufacturing process of printable electronics. We will survey the industrial tendency of printable electronics and flat panel display including some examples of inkjet printing and present the considerable points of inkjet printing method and some role of materials for successful inkjet printing.

• 한국진공학회:학술대회논문집
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• 한국진공학회 1997년도 제13회 학술발표회 논문개요집
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• pp.114-114
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• 1997

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 1996년도 추계학술대회 논문
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• pp.52-57
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• 1996

Conductive Ceramic Matrix Composite(CMC) of TIC/Al2O3 and Metal Matrix Composite (MMC) of SiC/Al were experienced by the die sinking Electrical Discharge Machining(EDM) for different current and duty factor according to negative polarity. Inthis experimental study Material Removal Rate(MRR) maximum surface roughness four point bending stress distribution and Scanning Electron Microscopy(SEM) Photographs were analysed. the higher MRR was obtained for CMC than MMC but slowly decreased around duty factor of 0.67 for MMC and better surface morphology was found CMC than MMC. The SEM photographs of discharge traces for CMC showe uniform shape about 100 to 200${\mu}{\textrm}{m}$ in diameter but MMC showed irregular shape.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.173-178
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• 2001

The materials processing factors such as remelting and casting, heat treatment and microstructure, sheet rolling and can body forming in the aluminum can-to-can recycling procedure have been investigated. Aluminum used beverage can(UBC) was remelted together with virgin aluminum. The ceramic filter was used during casting to remove large impurities. As-cast microstructure was composed of large intermetallic compound (mainly $\beta$ -phase) distributed in the aluminum matrix. By heat treatment, $\beta$ -phase was transformed to $\alpha$ -phase which was also formed from $Mg_2$Si particles. The heat treated ingots were hot-rolled at 48$0^{\circ}C$ and cold-rolled to thin sheets. Can making from this thin sheets was successful and earing was measured after can making. There was a critical cold reduction rate for minimum earing. Some cracks were initiated from the impurity particles which was not removed during filtering.

• The Korean Journal of Ceramics
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• 제1권4호
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• pp.209-213
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• 1995

The electrical conductivity was investigated in two series of alkali aluminosilicate glass melts, $25R_2O(R: Na and K)-xAl2O3-(75-x)SiO_2$ at temperatures ranging from 1000 to 140$0^{\circ}C$. The dependences of conductivity or activation energy on $Al_2O_3/R_2O$ of both series in the molten state showed a same behavior. These results in the molten state were compared with previous studies for sodium alkali aluminosilicate glasses in the molten and solid state, and explained in terms of the binding state: $[-O]-R^+\; and\; [AlO_4]-R^+$.

• The Korean Journal of Ceramics
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• 제1권4호
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• pp.185-190
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• 1995

Tribological behavior of the diamond-like carbon (DLC) films sliding on floppy disk has been investigated. Hydrogenated DLC films have been prepared by plasma enhanced chemical vapor deposition (PECVD) using methane and hydrogen mixture in different volume ratios on ferrite substrates. DLC films show lower friction coefficients (0.2~0.4) than those of the uncoated ferrite(0.4~0.5). DLC films containing more hydrogen exhibit higher wear resistance. To investigate the roughness effect on wear, the substrates were polished with SiC papers prior to deposition. Too fine or too rough DLC surfaces result in poor wear resistance. Wear resistance of annealed DLC films at higher temperature slightly increases with respect to as-deposited film.

• KSBB Journal
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• 제6권4호
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• pp.425-429
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• 1991

이상의 실험 결과로부터 다음과 같은 결과를 얻었다. 1. $TiO_2-SiO_2-AL_2O_3-B_2O_3-CaO-Na_2O$계에서 분상을 일으켰을 때 $600^{\circ}C$, 6시간 열처리시켰을 때 최대의 비표면적을 나타냈다. 2. 저온에서 열처리 시간이 증가하면 비표면적은 증가하고 고온에서는 열처리 시간이 증가하면 비표면적은 감소하다가 다시 증가한다. 3. 상분리 및 비표면적은 열처리 시간보다 열처리 온도에 더욱 민감하였다.

• The Korean Journal of Ceramics
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• 제6권4호
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• pp.364-369
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• 2000

Silicon nitride with adding La$_2$O$_3$ was sintered by gas pressure sintering (GPS) technique at $1950^{\circ}C$, in $N_2$ gas at 3 MPa, for 2h. Mechanical properties such as hardness, flexural strength, and fracture toughness were determined as a function of the GPS holding time and the contents of La$_2$O$_3$ in silicon nitride. Also machinability of silicon nitride ball with various GPS holding time and amount of La$_2$O$_3$ was evaluated by magnetic fluid grinding (MFG) method. In this study it was found that machinability was influenced significantly with La$_2$O$_3$ contents. However, the different GPS holding time did not affect the machinability very much.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.608-609
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• 2006

The deformation behavior under three-point bend test was found to depend on the loading uniformity and the macrostructure for SiC reticulated porous ceramics (RPCs). However, this dependence of loading uniformity is alleviated by improved macrostructure with fewer flaws and clogged pores. Even, this dependence becomes less important as the struts become thicker and stronger. The bend result of RPCs with highly uniform macrostructure is in excellent agreement with the GA (Gibson and Ashby) model, but the one with un-uniform macrostructure deviates from the GA model, suggesting that the macrostructure plays an important role in deformation behavior of RPCs under bend.

• 대한기계학회논문집A
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• 제29권1호
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• pp.14-21
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• 2005

Laser chemical vapor deposition can be an effective technique for a rapid prototyping with ceramic materials, in particular. The objective of the study is to fabricate several 3-dimensional objects by stacking multi-layers as well as to find out some basic aspects of a rapid prototyping with laser chemical vapor deposition such as deposition characteristics with traversing speed of the laser, possible problems in stacking multi-layers etc. The limit speed of the laser that can grow a tilted SiC rod was found in this study, and laser directing writing that occurs over the limit speed was also investigated. Finally, a zigzag-shaped rod, a spiral-shaped rod, a wall and a square duct were successfully fabricated with laser chemical vapor deposition of tetramethylsilane