• Title/Summary/Keyword: Surface coating

Search Result 260, Processing Time 0.158 seconds

Evaluation of Surface Coating Materials of Concrete for Protection of Chloride Attack (염해방지를 위한 콘크리트 표면도장재료의 성능평가)

  • 정해문;유환구;이병덕;안태송;오병환
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • /
    • pp.749-754
    • /
    • 2002
  • The safety and serviceability of concrete structures are influenced by corrosion of steel bars in concrete. Several methods have been available to protect the reinforcing bars from corrosion. Among them, the surface coating method is one of the easiest way to apply to concrete structures. However, the realistic guideline for surface coating materials has not been established yet in this country. In this study, in order to establish a reasonable technical guidelines which include the test method, quality criteria, and construction method, the performances of surface coating materials were evaluated.

  • PDF

A COMPARATIVE STUDY ON SURFACE ROUGHNESS OF GLASS IONOMER CEMENT BY SURFACE COATING AGENT (표면도포제에 따른 수복용 글라스 아이오노머 세멘트의 표면조도 비교)

  • Choi, Byung-Jai;Hwang, Dong-Hwan
    • JOURNAL OF THE KOREAN ACADEMY OF PEDTATRIC DENTISTRY
    • /
    • v.23 no.4
    • /
    • pp.915-924
    • /
    • 1996
  • The purpose of this paper is to investigate the surface roughness of glass ionomer cement during initial setting time followed by applying surface coating agent. No other finishing or polishing procedure is done and each surface coating agents (varnish, adhesive, gloss, sealant) are used after filling of glass ionomer cement. Surface roughness indices(Ra) are measured and surface contours are obtained electronically by Surfcorder SEF-30D(Kosaka laboratory Ltd., Japan). The results are as follows: 1. During initial setting time, surface roughness increases slightly regardless of surface coating agents. But it is statistically insignificant. (p>0.05) 2. Among surface coating agents used, Ra indices of group using varnish are high significantly compared to other groups regardless of elapsed time.(p<0.05) Among the groups which has used other surface coating agents except for the varnish group, similar Ra index all over the experiment is obtained, when compared to control group (no agent). 3. If no surface treatment is performed, tri-cure glass ionomer cement (Vitremer) has higher Ra Index than light cure glass ionomer cement (Fuji II LC) (t<0.05). But there is no difference between two groups in Ra index if any kinds of agents are applied except for sealant. (t>0.05)

  • PDF

Effect of Concrete Surface Coating on the Service Life Extension (콘크리트 표면도장에 의한 내구수명 연장효과)

  • Kim, Ki-Hyun;Cha, Soo-Won;Jang, Seung-Yup
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • /
    • pp.193-194
    • /
    • 2010
  • Developed is a chloride penetration analysis program that can consider a concrete surface coating. The effect of concrete surface coating on the service life is simulated by the developed finite element program. It was revealed that the coating at the earlier age is the more effective way to extend the service life.

  • PDF

Changes in the Process Efficiency and Product Properties of Pulp Mold by the Application of Oil Palm EFB (오일팜 EFB 섬유 적용에 따른 펄프몰드 공정효율 및 제품품질 변화)

  • Kim, Dong-Seop;Sung, Yong Joo;Kim, Chul-Hwan;Kim, Se-Bin
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.48 no.1
    • /
    • pp.67-74
    • /
    • 2016
  • The demand of environmental friendly packaging materials such as pulp mold has been increased. The application of the oil palm biomass, EFB (Empty Fruit Bunch) fiber as natural raw materials to the pulp mold could increase the usability of the pulp mold by the reduced production cost brought from the relatively low cost of EFB. The effects of the EFB(Empty Fruit Bunch) fibers on the properties of pulp mold and on the process efficiency were evaluated in this study. The pulp mold samples were prepared with mixture ONP (Old news paper) and EFB by using laboratory wet pulp molder. The changes in the drying efficiency were measured with the changes in the solid contents of pulp mold samples during drying process. The efficiency of the surface coating treatment on the pulp mold depending on the condition of the pulp mold samples were also evaluated in order to improve the water resistance properties of pulp mold. The addition of EFB increased the drying efficiency by providing the bulkier structure and the higher water contact angle, which indicated the better water resistance properties. The water resistance were improved by the surface coating treatments and the application of surface coating on the pulp mold at the higher moisture contents resulted in the higher improvement in the water resistance. The bulkier structure originated from the application of EFB fiber reduced the effects of the surface coating, which could be overcome by the control of surface coating process.

Effects of fluoride release and solubility of resin modified glass ionomer with surface coating agents (표면 코팅제의 레진 강화형 글라스아이오노머 불소 유리량 및 용해도에 대한 효과)

  • Yoon, Taewan;Yoo, Seunghoon
    • Journal of Dental Rehabilitation and Applied Science
    • /
    • v.35 no.2
    • /
    • pp.81-89
    • /
    • 2019
  • Purpose: This study aimed to investigate the correlation between the solubility and the amount of fluoride release when a resin surface coating agent is applied to RMGIC. Materials and Methods: To measure the fluoride release and solubility, Fuji II $LC^{(R)}$and $Filtek^{TM}$ Z350XT without a surface coating, Fuji II $LC^{(R)}$ with G coat $plus^{TM}$ and Fuji II $LC^{(R)}$ with $Permaseal^{(R)}$ were prepared. And the amount of fluoride release and solubility were measured. Results: There was no significant difference in the daily fluoride release between the surface coating agents. The cumulative fluoride release was significantly different between the groups using RMGIC at 56 days (P < 0.05). In the solubility measurement, RMGIC without surface coating was significantly different only on the 7th day compared to the other three groups (P < 0.05). Conclusion: Surface coating agents can prevent the degradation of properties by the initial solvent in RMGIC. Therefore, fluoride is preserved inside the restorative material and the effect of surface coating after the addition is reduced, so that the effect on fluoride release and storage is also reduced.

Quality Changes in Concrete According to the Number of Use of Aluminum Form Surface Coating Material (알루미늄 거푸집 표면코팅재의 전용횟수에 따른 콘크리트의 품질변화)

  • Lee, Il-Sun;Park, Byung-Kwan;Baek, Dae-Hyun;Park, Jae-Soon;Han, Min-Cheol;Han, Cheon-Goo
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • /
    • pp.123-126
    • /
    • 2009
  • This study is analyzed the effects of the number of use of aluminum form surface coating material on surface quality of concrete. The results can be summarized as follows. Surface roughness showed larger values with increase in the number of use. Values were larger in UP and AL compared to PE. While found to have bad influence on concrete surface quality, PA and W showed most excellent values for roughness. The number of surface pores increased with increasing number of use, and the number of pores on concrete surface was reduced by applying a remover. In terms of type of surface coating material, PA and W showed smallest number of pores in comparison to PE. In order to comprehensively improve surface quality of concrete, parallel use of PA coating material and remover is deemed most appropriate.

  • PDF

The effect of various surface coatings on microleakage and microhardness of light-cured glass ionomer restoration (수종 표면 보호재의 도포가 광중합형 유리 아이오너머 수복물의 변연 누출 및 미세 경도에 미치는 영향)

  • Kim, Gi-Seob;Kim, Yong-Kee
    • JOURNAL OF THE KOREAN ACADEMY OF PEDTATRIC DENTISTRY
    • /
    • v.24 no.3
    • /
    • pp.495-510
    • /
    • 1997
  • The purpose of this study was to evaluate the efficacy of several surface coating agents in preventing microleakage and increasing microhardness of light-cured glass ionomer restoration. 50 and 25 sound molar teeth were used for the microleakage test and microhardness test respectively. Data were analyzed statistically using Kruskal-Wallis and/or Mann-Whitney test. The results of the present study were as follows: 1. The effect of surface coating in reducing microleakage was proven only at the gingival margin of restorations with statistical significance(p<.05). 2. The distribution of microleakage score at gingival margin was shown to be better than that of occlusal margin in general but with no statistically significant differences(p>.05). 3. No statistically significant differences in microhardness could be found between groups (p>.05) regardless of depth of measurement. 4. Under the present experimental conditions, the types or application of surface coating agents did not impose any significant effect on microhardness of glass ionomer restorative material whereas the protective effect of surface coating in reducing microleakage was partly proven.

  • PDF

Laser Micro Machining and Electrochemical Etching After Surface Coating (미세 레이저 가공의 표면코팅 후 전해 에칭)

  • Kim, Tae Pung;Park, Min Soo
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.30 no.6
    • /
    • pp.638-643
    • /
    • 2013
  • Laser beam machining (LBM) is fast, contactless and able to machine various materials. So it is used to cut metal, drill holes, weld or pattern the imprinted surface. However, after LBM, there still leave burrs and recast layers around the machined area. In order to remove these unwanted parts, LBM process often uses electrochemical etching (ECE). But, the total thickness of workpiece is reduced because the etching process removes not only burrs and recast layers, but also the entire surface. In this paper, surface coating was performed using enamel after LBM on metal. The recast layer can be selectively removed without decreasing total thickness. Comparing with LBM process only, the surface quality of enamel coating process was better than that. And edge shape was also maintained after ECE.

Tribological behaviors of polymer coated carbon composite with small surface grooves (코팅된 요철표면을 가지는 탄소/에폭시 복합재료의 마찰 및 마모 특성)

  • Kim, Seong-Su;Lee, Hak-Gu;Lee, Dai-Gil
    • Proceedings of the Korean Society For Composite Materials Conference
    • /
    • /
    • pp.107-110
    • /
    • 2005
  • Tribological behaviors of carbon epoxy composites whose surfaces have many small grooves were compared with respect to coating method under dry sliding and water lubricating conditions. The surface coating materials were epoxy (Ep) and polyethylene (PE) mixed with self-lubricating $MoS_2$ and PTFE powders. The wear morphology of the composites observed with a scanning electron microscopic (SEM) revealed that the surface coating layer mixed with the self-lubricating powder on the grooved surface significantly improved the wear resistance under water lubricating condition because the surface coating layer blocked water to penetrate the composite surface and the self-lubricating powder reduced the wear on the coating by suppressing the generation of blisters.

  • PDF