• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1988년도 춘계학술대회 논문집
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• pp.88-91
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• 1988

In this paper, PLZT Ceramics were fabricated by two stage sintering method whose first stage vacuum hot pressing and second stage PbO atmosphere sintering. Using Graphite Mould instead of Alumina Mould in first stage prevented the adhision between PLZT substrate and the mould. The grain sizes of PLZT Ceramics were controlled by varying the hot pressing time and second sintering time.

• 한국세라믹학회지
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• 제29권2호
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• pp.143-151
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• 1992

Partially stabilized alpha-sialon composition (X=0.1) powder was hot-pressed at 1800~200$0^{\circ}C$ for 0~90 min with 30 MPa. Sintering behavior, phase changes and mechanical properties for the specimens were studied. As sintering temperature was raised from 1800 to 190$0^{\circ}C$, the relative density tended to increase and reached 99% of theoretical at 190$0^{\circ}C$. However the amount of alpha-sialon decreased because alpha-sialon transformed to beta-Si3N4 and yttrium rich silicate glass. In the case of hot-pressing at 190$0^{\circ}C$ for various times, densification increased with sintering time and full densification above 99% of theoretical was attained by 30 min. The amount of alpha-sialon decreased with sintering time. The maximum strength of 825 MPa was obtained by hot-pressing at 190$0^{\circ}C$ for 60 min.

• 한국전기전자재료학회논문지
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• 제12권1호
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• pp.50-55
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• 1999

We have investigated the $LiMn_2O_4$system as an cathode material for lithium rechargeable batteries. $LiMn_2O_4$spinel oxides have been synthesized by a solid state methode. We varied sintering time at a fixed sintering temperature of 75$0^{\circ}C$. In order to investigate the electrochemical properties of prepared $LiMn_2O_4$we assembled three-electrode cells using the working electrode as active material and Li metal as the counter and reference electrodes. The electrolyte was 1 M LiPE$_{6}$-EC:DEC(1:1 by volume). The particle size of sample synthesized at 75$0^{\circ}C$ ranged about 60$\mu m$. The discharge capacity of a cell involving spinel $LiMn_2O_4$ increased with increasing sintering time.e.

• 대한금속재료학회지
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• 제49권2호
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• pp.161-166
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• 2011

The aim of this study was to determine the effect of high-energy mechanical milling (HEMM) time and sintering temperature on microstructure and mechanical properties of the TiAl composite fabricated by pulse current activated sintering. TiAl intermetallic powders were milled by HEMM for 1h, 4h, and 8h respectively. Thermal analysis was used to observe the phase transformation of the milled TiAl powders. The sintering time decreased with increase of milling time. The hardness and fracture toughness of the sintered specimens also was improved with increasing milling time. The grain size of the sintered specimens which was milled for 4h was in the range of 50~100 nm.

• 한국전기전자재료학회논문지
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• 제36권5호
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• pp.505-512
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• 2023

This study investigated crystal structures, microstructures, and electric-field-induced strain (EFIS) properties of Bi-based lead-free ferroelectric/relaxor composites. Bi_1/2Na_0.82K_0.18)_1/2TiO₃ (BNKT) as a ferroelectric material and 0.78Bi_1/2(Na_0.78K_0.22)_1/2TiO₃-0.02LaFeO₃ (BNKT2LF) as a relaxor material were synthesized using a conventional solid-state reaction method, and the resulting BNKT2LF powders were subjected to high-energy ball milling (HEBM) after calcination. As a result, HEBM proved a larger average grain size of sintered samples compared to conventional ball milling (CBM). In addition, the increased sintering time led to grain growth. Furthermore, HEBM treatment and sintering time demonstrated a significant effect on EFIS of BNKT/BNKT2LF composites. At 6 kV/mm, 0.35% of the maximum strain (S_max) was observed in the HEBM sample sintered for 12 h. The unipolar strain curves of CBM samples were almost linear, indicating almost no phase transitions, while HEBM samples displayed phase transitions at 5~6 kV/mm for all sintering time levels, showing the highest S_max/E_max value of 700 pm/V. These results indicated that HEBM treatment with a long sintering time might significantly enhance the electromechanical strain properties of BNT-based ceramics.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 하계학술대회 논문집
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• pp.328-329
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• 2009

This paper presents the effect of organic Ag complex sintering temperature on the MEH-PPV photoluminescence (PL) properties. MEH-PPV and organic Ag complex was coated on the glass substrate by spin coating method. The coated Ag complex was sintered in an air atmosphere. The sintering temperature was varied from 100 to $200^{\circ}C$ and sintering time was 5 min. The Ag film sintered at temperature higher than $120^{\circ}C$ shows very low sheet resistance less than $0.5\;{\Omega}{/\square}$. The coated MEH-PPV measure photoluminescence (PL) intensity at 580 nm. The PL peak was shifted to the higher wavelength with increasing the sintering temperature.

• 한국세라믹학회지
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• 제38권8호
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• pp.687-692
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• 2001

Silicon nitride-La-silicon oxynitride ceramics were fabricated by Spark Plasma Sintering (SPS). The density, crystalline phase and microstructure were compared with those obtained by Hot Pressing (HP). The full density was achieved within 40 min by spark plasma sintering at 1$650^{\circ}C$, whereas the same result was required by hot pressing with a dwell time of 500 min at higher temperature. There were some differences in the microstructure and second phases in the sintered ceramics, which are attributed to the rapid densification in the spark plasma sintering. The fine and acicular grain microstructure appeared in spark plasma sintering.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.1389-1393
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• 2007

Selective Laser Sintering (SLS) is currently recognized as a leading process in the new field of solid freeform fabrication (SFF). It is used to fabricate in a short time any 3 dimensional shapes by layer-by-layer sintering of polymer, ceramic or metal powder. To develop this SFF system, it needs effective laser scanning path, temperature and z-axis control for lamination. Therefore, in this study, through the application of control algorithm for sintering process have performed, temperature evaluation for sintering process has performed and the manufacturing sample using SLS process.

• 한국세라믹학회지
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• 제27권3호
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• pp.337-344
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• 1990

As a function of sintering temperature and time, the electrical properties of ruthenium based thick film resistors were investigated with microstructure. The variatio of resistivity and TCR(temperature coefficient of resistance)trends of sintered speciman at various sintering temperature were different low resistivity paste(Du Pont 1721) from high one(Du Pont 1741). These phenomena are deeply relative to microstructure of sintered film. With increasing the sintering temperature for 1721 system, the electrical sheet resistivity decreased, but again gradually increased above 80$0^{\circ}C$. And TCR trends in 1721 system are all positive. On the other hand the electrical sheet resistivity of 1741 resistor system decreased with sintering temperature. And TCR trends variable according to sintering temperature. TCR of speciman sintered at $700^{\circ}C$ was negative value, and TCR of 80$0^{\circ}C$ sintered speciman coexisted negative and positive value. But in case of speciman sintered at 90$0^{\circ}C$, TCR was positive value. As results of this fact, it was well known that the charge carrier contributied to electrical conduction in 1741 resistor system varied with sintering temperature.

• 한국산업안전학회:학술대회논문집
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• 한국안전학회 1998년도 추계 학술논문발표회 논문집
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• pp.29-39
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• 1998

It is well known for 410L ferritic stainless steel powder to applicate a sensor ring in anti-lock brake system of automobile, several studies, because of its excellent magnetic properties. This study was carried out In investigate the magnetic properties such as the maximum magnetic induction, coercivity and maximum permeability of the materials with functions of sintering density! time and temperature, and concluded as follows； 1. Sintering under the circumstances of hydrogen gas and tile temperature of $1250^{\circ}C$ for 60min. showed that nitrogen was increased, whereas carbon and oxygen decreased in quantities. 2. Both maximum magnetic induction value of 4700Gauss and permeability of 200 were obtained at the maximum sintering density of 6.89g/$cm^3$. Here, the properties showed a linear increasement with increasing the sintering density. 3. Coercivity sharply increased with incresing the sintering density and reached to 7.6Oe at the maximum sintering density of 6.89g/$cm^3$.