• Journal of the Korean Ceramic Society
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• v.56 no.2
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• pp.111-129
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• 2019

Recently, all-solid-state batteries (ASSBs) have attracted increasing interest owing to their higher energy density and safety. As the core material of ASSBs, the characteristics of the solid electrolyte largely determine the performance of the battery. Thus far, a variety of inorganic solid electrolytes have been studied, including the NASICON-type, LISICON-type, perovskite-type, garnet-type, glassy solid electrolyte, and so on. The garnet Li₇La₃Zr₂O₁₂ (LLZO) solid electrolyte is one of the most promising candidates because of its excellent comprehensively electrochemical performance. Both, experiments and theoretical calculations, show that cubic LLZO has high room-temperature ionic conductivity and good chemical stability while contacting with the lithium anode and most of the cathode materials. In this paper, the crystal structure, Li-ion transport mechanism, preparation method, and element doping of LLZO are introduced in detail based on the research progress in recent years. Then, the development prospects and challenges of LLZO as applied to ASSBs are discussed.

• Journal of Korea Foundry Society
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• v.18 no.5
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• pp.474-480
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• 1998

Microstructural characteristics of semi-solid state processed hypereutectic Al-Si alloys have been investigated. Main concern of the present study is to investigate the effects of P and Sr addition on the size and morphology change of the primary Si particles. Refinement of the primary Si particles was observed with the addition of P and Sr at the early stage of semi-solid state processing, but such a refining effects became negligible resulting in Si particles with a near-spherical morphology with continuous stirring. This implies that the microstructural transformation mechanism became more dependent to stirring effects than to the alloying effects during semi-solid state processing. Brittle fracture and agglomeration were proposed as the mechanisms for microstructural alterations during semi-solid state processing.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.680.2-680.2
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• 2006

• Journal of Ceramic Processing Research
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• v.19 no.5
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• pp.413-418
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• 2018

All-solid-state lithium batteries (ASSBs) using inorganic sulfide-based solid electrolytes are considered prospective alternatives to existing liquid electrolyte-based batteries owing to benefits such as non-flammability. However, it is difficult to form a favorable solid-solid interface among electrode constituents because all the constituents are solid particles. It is important to form an effective electron conduction network in composite cathode while increasing utilization of active materials and not blocking the lithium ion path, resulting in excellent cell performance. In this study, a mixture of fibrous VGCF and spherical nano-sized Super P was used to improve rate performance by fabricating valid conduction paths in composite cathodes. Then, composite cathodes of ASSBs containing 70% and 80% active materials ($LiNi_{0.6}Co_{0.2}Mn_{0.2}O_2$) were prepared by a solution-based process to achieve uniform dispersion of the electrode components in the slurry. We investigated the influence of binary carbon additives in the cathode of all-solid-state batteries to improve rate performance by constructing an effective electron conduction network.

• Transactions of Materials Processing
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• v.8 no.3
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• pp.313-318
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• 1999

Many products related to automobile and airplane industry have been manufactured by semi-solid forging. In this paper finite element analysis of product by combined extrusion in semi-solid state was performed and its experimental verification using A356 was conducted. distribution of solid fraction was analyzed and compared with the experimental microstructure in the product. In addition, distribution of temperature in the product was analysed by finite element method.

• Journal of Practical Agriculture & Fisheries Research
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• v.23 no.1
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• pp.39-48
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• 2021

In this study, characteristics of solid-state fermentation distilled spirits with nuruk (fermentation starter) and sorghum were investigated. The starch digestion activity was highest in black koji (A. usamii) at 359.15 U/g dry base, white koji (A. luchuensis) at 306.98 and yellow koji (A. oryzae) at 15.31 was followed. The pH of the solid-state fermented mash in yellow, white and black koji showed 5.09, 4.46 and 4.50 respectively with significant differences (p<0.001). The total acid content of white and black koji was 0.73% as citric acid. The alcohol content of mash prepared with yellow, white and black koji was 4.34, 4.24, 3.89% respectively. The contents of reducing sugar showed 3.28, 3.23 and 2.64%. Total sugar were 14.88, 17.84 and 17.60% respectively. The alcohol content of each distillate ranged from 44.3 to 39.9%, and the furfural content in yellow koji was 1.25 times lower than the others.

• Transactions of Materials Processing
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• v.6 no.4
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• pp.319-328
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• 1997

A flow stress involving strain, solid fraction, and breakage ratio, and solid fraction updating algorithm were proposed to depict the deformation behavior of materials at the semi-solid state. In case of isothermally simple upsetting of Sn-15%Pb alloy at the semi-solid state, by comparing the results of finite element analysis with the existing experimental results, the reliability of both the developed flow stress and updating algorithm were investigated. It was found that the verified program can effectively be used in the rigid-viscoplastic finite element analysis of the semi-solid forging processes.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.1263-1264
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• 2013

• Journal of the Korean Ceramic Society
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• v.41 no.8
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• pp.582-587
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• 2004

Biphasic Calcium Phosphate (BCP) consisted of hydroxyapatite (HAp) and $\beta$-tricalcium phosphate (P-TCP) has been prepared by solid state reaction. The size reduction of the resultant BCP agglomerate was carried out by reaction with hot water under atmospheric condition uld also under high pressure using an autoclave. The influence of processing conditions on the change of crystalline phase and composition, relative amount of constituent, specific surface area, and microstructure was investigated by means of XRD, FT-IR, BET method using a nitrogen adsorption and SEM.

• Journal of Powder Materials
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• v.10 no.3
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• pp.168-171
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• 2003

Interpenetrating phase composites of $TiB_2$-Cu system were produced via Spark-Plasma Sintering (SPS) oi nanocomposite powders. Under simultaneous action of pressure, temperature and electric current titanium diboride nanoparticles distributed in copper matrix move, agglomerate and form a fine-grained skeleton. Increasing SPS-temperature and he]ding time promote densification due to local melting of copper matrix When copper melting is avoided the compacts contain 17-20% porosity but titanium diboride skeleton is still formed representing the feature of SPS . High degree of densification and formation of titanium diboride network result in increased hardness of high-temperature SPS-compacts.