• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.599-600
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• 2006

This paper described the state of art of porous metal materials, the typical manufacturing technologies and performances of sintered metal porous materials, with emphasis on the recent research achievements of CISRI in development of porous metal materials. High performance porous metal materials, such as metallic membrane, sub-micron asymmetric composite porous metal, large dimensional and structure complicated porous metal aeration cones and tube, metallic catalytic filter elements, lotus-type porous materials, etc, have been developed. Their applications in energy industry, petrochemical industry, clean coal process and other industrial fields were introduced and discussed.

• 대한치과기공학회지
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• 제35권4호
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• pp.281-286
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• 2013

Purpose: Surface modification is important techniques in modern dental and orthopedic implants. This study was performed to try embedding of bioactive materials in porous Ti implants. Methods: Porous Ti implant samples were fabricated by sintering of spherical Ti powders in a high vacuum furnace. It's diameter and height were 4mm and 20mm. Embedding process was used to suction and vacuum chamber. Loading properties of porous Ti implants were evaluated by scanning electron microscope(SEM), confocal laser scanning microscope(CLSM), and UV-Vis-NIR spectrophotometer. Results: Internal pore structure was formed fully open pore. Average pore size and porosity were $10.253{\mu}m$ and 17.506%. Conclusion: Porous Ti implant was fabricated successfully by sintering method. Particles are necking strongly each other and others portions were vacancy. This porous structure can be embedded to bioactive materials. Therefore bioactive materials will be able to embedding to porous Ti implants. Bioactive materials embedding in the porous Ti implant will induced new bone faster.

• 한국세라믹학회지
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• 제45권12호
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• pp.832-838
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• 2008

Diatomite, bentonite and zeolite were used as porous materials for fabricating hygroscopic panels. Moisture adsorption and desorption of porous materials were investigated and hydrothermal method was applied to fabricate panels. Cheolwon diatomite and Pohang zeolite showed excellent characteristics of moisture adsorption and desorption. These characteristics were caused by higher surface area and pore volume of porous materials. Correlation coefficient between surface area and moisture adsorption content of porous materials was 0.93. Moisture adsorption contents were influenced by surface area and pore volume of panels, and surface area more effected on moisture adsorption. Correlation coefficient between surface area and moisture adsorption content of panels was 0.86. Moisture adsorption content of panel with 10% Pohang zeolite was $180\;g/m^2$ and that of 10% Cheolwon diatomite was $170\;g/m^2$. Moisture desorption content of panel with 10% Pohang zeolite was $105\;g/m^2$. Moisture adsorption contents of panel with porous materials were higher than that of panel without porous materials.

• 한국세라믹학회지
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• 제46권6호
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• pp.627-632
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• 2009

Formaldehyde emissions from the construct was harmful to human. Diatomite, bentonite and zeolite were used as porous materials for fabricating panels. Formaldehyde adsorption and physical characteristics of porous materials were investigated and hydrothermal method was applied to fabricate panels. Formaldehyde adsorption contents of panels with porous materials were higher than that of panel without porous materials. The panels with Cheolwon diatomite and Pohang zeolite showed excellent characteristics of Formaldehyde adsorption. These characteristics were caused by higher surface area and pore volume of porous materials. Formaldehyde adsorption contents were influenced by surface area and pore volume of panels. Correlation coefficient between surface area and Formaldehyde adsorption content of panels was 0.87. The panels with porous materials had higher strength than that without porous materials because of bridging role particles.

• 한국재료학회지
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• 제32권3호
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• pp.115-124
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• 2022

Porous basalt aggregate is commonly used in roadbed engineering, but its application in concrete has rarely been studied. This paper studies the application of porous basalt in concrete. Porous basalt aggregate is assessed for its effects on mechanical strength and durability of prepared C50 concrete; because it has a hole structure, porous basalt aggregate is known for its porosity, and porous basalt aggregates can be made full of water through changing the content of saturated basalt; after full-water condition is achieved in porous basalt aggregate mixture of C50 concrete, we discuss its mechanical properties and durability. The effects of C50 concrete prepared with basalt aggregate on the compressive strength, water absorption, and electric flux of concrete specimens of different ages were studied through experiments, and the effects of different replacement rates of saturated porous basalt aggregate on the properties of concrete were also studied. The results show that porous basalt aggregate can be prepared as C50 concrete. For early saturated porous basalt aggregate concrete, its compressive strength decreases with the increase of the replacement rate of saturated aggregate; this occurs up to concrete curing at 28 d, when the replacement rate of saturated basalt aggregate is greater than or equal to 40 %. The compressive strength of concrete increases with the increase of the replacement rate of saturated aggregate. The 28 d electric flux decreases with the increase of the replacement rate of saturated aggregate, indicating that saturated porous basalt aggregate can improve the chloride ion permeability resistance of concrete in later stages.

• 한국세라믹학회지
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• 제39권10호
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• pp.919-927
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• 2002

표면층과 내부간의 기공구조가 다른 다공질체를 제조하기 위해 입자크기가 다른 두 종류의 분체를 이용하여 다공질 성형체를 제조하였다. 두 층간의 소결 수축율을 동일하게 제어하기 위해 성형밀도 변화에 따른 소결밀도 변화를 예측할 수 있는 Ford＇s equation을 도입하여 소결 수축율을 동일한 조건을 구하였다. 제조된 다공질체는 미세구조와 통기도를 조사함으로서 기공의 이중 구조화 여부를 평가하였다. SEM 관찰결과 기공크기가 다른 두 층으로 구성되어 있는 것을 확인하였다. 각 층의 통기도는 출발 입자크기와 기공율이 클수록 증가하였으며, 이중 기공구조를 갖는 시편의 통기도는 기공크기가 작은 층의 특성에 의존하였다.

• Journal of Electrochemical Science and Technology
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• 제15권1호
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• pp.111-131
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• 2024

Lignin-derived porous carbon has been identified as a versatile electrode material for supercapacitors (SCs) in energy storage systems (ESSs) owing to their intrinsic advantages including good electrical conductivity, low cost, high thermal and chemical stability, and high porosity, which stem from high surface, appropriate pore distribution, tailored morphologies, heterostructures, and diverse derivates. In this review, to provide a fundamental understanding of the properties of lignin, we first summarize the origin, historical development, and basic physicochemical properties. Next, we describe essential strategies for the preparation of lignin-derived porous carbon electrode materials and then highlight the latest advances in the utilization of lignin-derived porous carbon materials as advanced electrode materials. Finally, we provide some of our own insights into the major challenges and prospective research directions of lignin-derived porous carbon materials for supercapacitors. We believe that this review will provide general guidance for the design of next-generation electrode materials for supercapacitors.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2009년도 춘계학술발표대회
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• pp.3.1-3.1
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• 2009

Normal sintering process of producing porous ceramics is not to sinter perfectly, i.e., stop sintering in middle-process. Our porous ceramic materials are a product of complete sintering. For example if one want to make a porous carborundum, raw carborundum powder is sintered at either lower temperatures than normal sintering temperature or shorter sintering periods than normal sintering time to obtain incompletely sintered materials, i.e., porous carborundum. This implies normally sintered porous ceramic materials can mot be used in high vacuum conditions due to dust coming out from uncompleted sintering. We could produce completely sintered porous ceramic materials. For example, we can produce porous carborundum material by using carborundum particles bonded by glassy material. The properties of this material are similar to carborundum. We could make quasi-zero thermal expansion porous material by using carborundum and particles of negative thermal expansion materials bonded by the glassy material. We apply to sinter them also by microwave to sinter quickly. We also use HIP process to introduce closed pores. We could sinter them in large size to produce $2.5m{\times}2.5m$ ceramic plate to use as a precision plate for flat display industries. This flat ceramic plate is the world largest artificial ceramic plate. Precision plates are basic importance to any advanced electronic industries. The produced precision plate has lower density, lower thermal expansivity, higher or similar damping properties added extra properties such as vacuum vise, air sliding capacity. These plates are highly recommended to use in flat display industries. We could produce also cylindrical porous ceramics materials, which can applied to precision roller for polymer film precision motion for also electronic industries.

• 한국재료학회지
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• 제28권1호
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• pp.62-67
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• 2018

Active clay, bentonite and zeolite were used as porous materials for humidity controlling ceramic boards. The specific area and the pore volume of active clay were higher than bentonite and zeolite. The flexible strength of the gypsum board decreased with an increasing amount of porous material, and the flexible strength was lowest when active clay with a higher specific surface area than others porous materials was added. The specific surface area and total pore volume of ceramic boards containing porous material were highest at $102.25m^2/g$, $0.142cm^3/g$, respectively, when the active clay was added. In addition, as the amount of added porous materials increased, the specific surface area and total pore volume of the ceramic board increased, but the average pore diameter decreased. The addition of s porous materials with a high specific area and a large pore volume improved the moisture absorptive and desorptive performance of the ceramic board. Therefore, in this experiment, the moisture absorptive and desorptive properties were the best when active clay was added. Furthermore, as the amount of added porous materials increased, the moisture absorptive and desorptive properties improved. When 70 mass% of active clay was added to ${\alpha}$-type gypsum, the hygroscopicity was the highest, about $300g/m^2$, in this experiment.

• 한국재료학회지
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• 제18권6호
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• pp.289-293
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• 2008

Porous HAp with three-dimensional network channels was prepared in a polymer foam process using a in-situ formation. HAp/polyol with various HAp solid contents was formed with an addition of isocyanate. Under all conditions, the obtained porous HAp had pore sizes ranging $50\;{\mu}m$ to $250\;{\mu}m$. The influence of the HAp content on the physical and mechanical properties of porous HAp scaffolds was investigated. As the solid content increased, the porosity of the porous HAp decreased from 79.3% to 77.9%. On the other hand, the compressive strength of the porous HAp increased from 0.7 MPa to 3.7 MPa. With a HAp solid content of 15 g, the obtained porous HAp had physical properties that were more suitable for scaffolds compared to other conditions.