• Proceedings of the Korea Concrete Institute Conference
• /
• 2000.10a
• /
• pp.567-570
• /
• 2000

This study is designed to manufacture the continuous foamed concrete and the sound absorption characteristics investigation due to continuous voids ratio. According to the results of experiment, it was shown that continuous voids of the foamed concrete has the influence of the amount used of foaming agent, the viscosity and flowability of cement paste, and also is shaped by cohesive power of bubbles. Also the sound absorption ratio of the foamed concrete is subject to increase as the density becomes low by raising the continuous voids ratio. The cement paste with low water-cement ratio and high cement fineness are very effective to prevent weak strength of formed concrete caused by the increase of the porosity.

• Proceedings of the Korea Concrete Institute Conference
• /
• 1993.10a
• /
• pp.144-149
• /
• 1993

The results of an experimental study on the manufacture and the mechanical properties of carbon fiber reinforced silica fume.cement composites and light weight fly ash.cement composites are presented in this paper. The CF reinforced silica fume.cement composites using silica fume early strength cement were prepared with Pan-derived or Pitch-derived CF, and Lt. Wt, fly ash.cement composites using fly ash, early strength cement, perlite and a small amount of foaming agent. As the test results show, the flexural strength, toughness and ductility of CF reinforced silica fume .cement composites were remarkably increased by fiber contents. Also, the manufacturing process technology of Lt. Wt. fly ash.cement composites was developed and its optimum mix proportions were proposed. And the compressive and flexural strength of the fly ash.cement composites by hot water cured were improved even more than by moist cured, but are decreased by increasing fly ash replaced ratio for cement.

• Proceedings of the Korean Society For Composite Materials Conference
• /
• 2004.10a
• /
• pp.143-146
• /
• 2004

Pultrusion process of phenolic foam composite is investigated. Phenolic foam composites provide heat and flame resistance with less weight. When made into foam, a variety of properties can be obtained with different bubble size and number density. In this study, effect of process variables on the foaming characteristics of phenolic resin composites during pultrusion process has been studied experimentally. The process variables considered are the heating temperature and the pulling speed as well as the mass fraction of blowing agent. Experiments were performed using a laboratory scale pultrusion apparatus. Optimal process condition was found by observing the micro-morphology.

• Proceedings of the Korean Institute of Surface Engineering Conference
• /
• 2018.06a
• /
• pp.33.2-33.2
• /
• 2018

현재 업계에서 사용 중인 대부분의 탈지제는 중온 및 고온에서 사용하는 제품이 많으며, 거품의 발생 또한 많으므로 소포제를 넣지 않고서는 사용이 불가능한 약품이 대부분이다. 탈지제 거품의 발생은 탈지제의 세정력을 높이기 위해 주로 사용되는 음이온성 계면활성제의 특성에 의해 나타나게 되는데, 본 연구에서는 음이온성 계면활성제를 사용하지 않음으로 기포의 발생을 억제하고, 동시에 상온에서 사용할 수 있는 약품을 개발함으로써 생산 공정에서의 원가절감과 신뢰성 및 양산성의 향상을 도모하는데 그 목적이 있다.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2019.05a
• /
• pp.203-204
• /
• 2019

Recently, exposed concrete designs have been placed everywhere due to increased interest in indoor residential environments. In addition, in order to overcome the disadvantages of litracon, which was developed by mixing optical fiber, LEFC(Light Emotion Friendly Concrete) was developed in Korea, which improved unit price and constructivity by inserting hard acrylic rods. LEFC, using foaming agent and lightweight aggregate for light weighting, has disadvantages that decrease mechanical properties, and thus improved mechanical properties by using ultra-high performance concrete. Also, due to the characteristics of UHPC materials, it showed excellent self-consolidating performance. Considering these characteristics, a LEFC mold with pattern design was developed. The LEFC blocks were built so that pattern shapes could be seen and these were applied on-site to Sewoon plaza, located in Seoul.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2018.11a
• /
• pp.38-39
• /
• 2018

Foame concrete was used to reduce insulation problems and interlayer noise in slab. There have been no studies on the physical properties of foaming agents using foamed concrete,Only the physical properties of foamed concrete mixed with foam agent. It is judged that the density and distribution of Foams will be changed when the pressre is changed when the bubble is formed. In this study to investigate the changes of Foam density and the physical performance of foamed concrete by changing the pressure during Foam formation.

• Advances in concrete construction
• /
• v.3 no.2
• /
• pp.103-111
• /
• 2015

The foam concrete was fabricated by adding the foaming agent which composite ordinary Portland cement with plant and animal protein into cement paste, and the electromagnetic wave absorption properties were studied for the first time as well. The studies showed that the electromagnetic waves can be absorbed by multiple reflections and scattering within the porous material. Thickness and filling ratio have a great influence on the electromagnetic wave absorbing properties in 2-18 GHz of the foam concrete, the greater the thickness, the better the performance of absorption; filling ratio was about 52 vol.%, the absorbing properties achieved the best.

• Proceedings of the KSME Conference
• /
• 2004.04a
• /
• pp.1114-1119
• /
• 2004

In a foaming process of microcellular plastics (MCPs) with a injection molding, research on the viscosity change that occurs when the gas is injected to the polymer has received little attention despite its importance. The purpose of this paper is to provide the basic data required to determine the processing condition by measuring viscosity changes against the gas injection rates of the blowing agent, and to verify the influence of the viscosity change on the flow condition of polymer inside the mold at the injection process.

• Elastomers and Composites
• /
• v.53 no.3
• /
• pp.131-135
• /
• 2018

This study was aimed at improving the white index (WI) to prepare thermally expandable microspheres for wallpaper. In particular, thermally expandable microspheres were prepared for different colloidal silica particle sizes to study thermal properties, foaming ratio, and WI. The spheres obtained from tiny colloidal silica were the best in terms of WI and yellowing. Additionally, thermogravimetric analysis results show that small colloidal silica particles are more likely to be adsorbed physically or chemically to the microsphere surface, thereby improving WI at higher temperatures.

• Proceedings of the Korean Powder Metallurgy Institute Conference
• /
• 2006.09a
• /
• pp.91-92
• /
• 2006

Metallic foams have a combination of attractive properties such as high specific mechanical properties and good energy absorption characteristics. This paper presents the properties of steel foam sandwiches produced using powder metallurgy approach. Metallic powder, solid polymeric binder and a foaming agent are dry-mixed and molded into the desired shape. The molded powder mix is then heat-treated to foam, debind and sinter the material. The resulting material has an open cell structure with high porosity. The structure and properties of sandwiches specimens produced with the process are presented and discussed.