• Journal of the Korean Ceramic Society
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• v.30 no.10
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• pp.845-851
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• 1993

Low firing temperature substrate were synthesized through tape casting and sintering of glass with cordierite composition and then their properties were investigated. Even though the dielectric properties and XRD patterns of substrates, obtained by tape casting and sintering at 900~100$0^{\circ}C$ for various periods, were similar to those of substrates obtained by dry pressing, the sinterability was enhanced. The substrates were thin and the size was 0.6$\times$50$\times$50mm. From the results of dielectric properties, the sinterability and X-ray diffraction pattern, the proper condition for cofiring process with conductor, Cu, was 90$0^{\circ}C$ for 1h. The properties of the substrate are as follows; the dielectric constant was 5.31(at 1MHz), the dissipation factor was 0.0028, the apparent porosity was 0.28% and the main crystalline phase was $\alpha$-cordierite.

• Journal of the Korean Ceramic Society
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• v.41 no.9
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• pp.647-652
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• 2004

In aqueous tape casting of alumina slurry systems, the relationships between the suspension compositions and the defects of the dried tapes were discussed. The suspensions compositions were controlled with the ratios of the solids, water and organics binder contents. The effects of the thickness of dried tape and kinds of binder system were also examined. In the defect free region, the apparent viscosity showed nearly same value due to the count balancing effect of solid and organic binder content on the apparent viscosity. When water content was constant, increasing solid led to decrease of organic binder content. The defect free region was narrowed with increasing of casting thickness. When linear type acrylic emulsion binders system (D1000 and D 1035) were used, defect free zone formed the belt type in the triangle of solid, water and organic binder content according to the line of constant water contents. However the defect free region was not found in the cross-link type emulsion binder system (D 1050).

• Journal of the Korean Society for Heat Treatment
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• v.17 no.5
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• pp.293-298
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• 2004

For the application of heat sink device, the green sheets of powder of W-XCu and Mo-XCu composites were fabricated by tape casting technique. The mixing ratio of powder and binder was 6:4. The green sheet was shrinked up to 10~20% after sintering and the maximum relative density was above 95%. Thermal conductivity and Thermal expansion systematically increased with increasing Cu contents. The maximum thermal conductivity of W-20wt.%Cu was about 206[W/mK].

• Journal of the Korean Ceramic Society
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• v.43 no.9 s.292
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• pp.519-526
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• 2006

A full-factorial design of experiments with three input factors and two levels for each factor including center points was utilized for the preparation and characterization of twelve types of $BaTiO_3$ slips for tape casting. Ceramic powders with different particle sizes, different milling methods such as high energy milling and conventional ball milling, and two types of dispersant with different polymeric species were chosen as input factors in order to investigate their effects on slip and on green tape properties. Tape casting, a small rectangular-shaped K-square preparation, characterization and quantitative data analysis using statistical software were followed. Ceramic powder was the most significant among three input factors for the output responses of slip viscosity and green tape density, showing more favorable results with large particles than with very fine ones. In addition, high energy milling for only 30 min was more efficient than 24h of conventional ball milling in terms of powder dispersion and milling. The optimum condition based on the experimental results was a slip exposed to high energy milling with large ceramic particles along with a methylethyl acetate dispersant.

• Journal of the Korean Ceramic Society
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• v.36 no.10
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• pp.1123-1131
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• 1999

Alumina-glass composites which are considered as the material of the choice for all dental crown was prepared by aqeous-based tape casting and sintering for 2h at 1120$^{\circ}C$ followed by glass infiltration for 2h at 1100$^{\circ}C$ Biaxial strength and fracture toughness of the composites were evaluated to determine the optimum composition of the tape as a function of the amount of constituent such as alumina binder and plasticizer. The strength and the fracture toughness of the alumina tape increased with increasing the contents of alumina and binder. These observations are consistent with in fluence of the constituents on mean alumuna particle distance in tapes suggesting that high strength of the glass infiltrated alumina composites is related to toughening by crack bowing. The biaxial strength and the fracture toughness of the composite containing the optimum constituent composition were 523 MPa and 3.3 MPa$.$1/2 respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.168-168
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• 2008

고체산화물 연료전지의 전해질로 사용되는 상용의 YSZ powder는 나노 크기의 입자로서 습식 후막 성형을 위한 분산공정에 많은 문제를 가지고 있다. 기존 tape casting을 이용한 후막 공정의 경우 수 micron 대역의 powder가 주로 사용되었고 MLCC 공정에서 sub micron 크기의 입자가 상용으로 적용되는 수준에 있다. 그러므로 아직 후막 공정이 확립되지 않은 YSZ의 경우 수십 nano 크기 powder의 분산과 casting에 관한 연구 결과 보고는 아직 미흡하다. 본 연구에서는 이러한 연구 필요성에 따라 수십 nano의 입자크기를 나타내는 YSZ 입자의 고농도 분산 조건을 위한 분산제와 용매 량에 대한 기본적인 실험 결과를 제시하고자 하였다. 그리고 이 결과에 기초하여 기존 tape casting 공정에서 사용되는 유기 binder system을 이용하여 후막의 casting 조건 및 sheet의 균일성 확보 조건을 확인 하고자 하였다.

• Journal of the Korean Ceramic Society
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• v.53 no.6
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• pp.622-627
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• 2016

The effects of the debinding atmosphere on the properties of sintered reaction-bonded $Si_3N_4$ (SRBSN) ceramics prepared by tape casting method were investigated. Si green tape was produced from Si slurry of Si powder, using 11.5 wt% polyvinyl butyral as the organic binder and 35 wt% dioctyl phthalate as the plasticizer. The debinding process was conducted in air and $N_2$ atmospheres at $400^{\circ}C$ for 4 h. The nitridation process of the debinded Si specimens was performed at $1450^{\circ}C$, followed by sintering at $1850^{\circ}C$ and 20 MPa. The results revealed that the debinding atmosphere had a significant effect on $Si_3N_4$ densification and thermal conductivity. Owing to the higher sintered density and larger grain size, the thermal conductivity of $Si_3N_4$ specimens debinded in air was higher than that of the samples debinded in $N_2$. Thus, debinding in air could be suitable for the manufacture of high-performance SRBSN substrates by tape casting.

• The Korean Journal of Ceramics
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• v.5 no.2
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• pp.119-124
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• 1999

Silicon nitride ceramics with highly oriented microstructure were prepared by tape casting a slurry containing 5 wt% of the silicon nitride whiskers. The whiskers were aligned in the casting direction and worked as seeds for the grain growth. The anisotropy was observed from the sintering shrinkage, Vickers indentation crack lengths, and XRD patterns. The cracks were much longer on the surface normal to the aligned grains than on the tape casting surface where the lateral cracks were also observed. The effect of sintering additives and the annealing treatment on the indentation crack length was examined. The sample with higher silica content had longer cracks than the one with lower silica content. The crack length anisotropy increased after annealing at 2123K.

• Journal of the Korean Ceramic Society
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• v.33 no.8
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• pp.883-888
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• 1996

• Proceedings of the Korean Ceranic Society Conference
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• 2003.10a
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• pp.123.2-123
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• 2003