• Title/Summary/Keyword: Roughness of surface treatment

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A STUDY ON THE SURFACE ROUGHNESS OF GLAZED PORCELAIN AND POLISHED PORCELAIN (글레이징처리한 도재와 연마한 도재의 표면조도에 관한 연구)

  • Choi, Mee-Ra;Chung, Hun-Young;Lee, Sun-Hyeong;Yang, Jae-Ho
    • The Journal of Korean Academy of Prosthodontics
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    • v.36 no.4
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    • pp.549-565
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    • 1998
  • Porcelain is considered to be one of the materials of choice for restoration where esthetics is of concern. But porcelain surface without final glazing treatment may induce undesirable results such as inflammatory response on adjacent soft tissues due to plaque accumulation and increased wear of opposing teeth. Therefore, rough porcelain surface must be smoothened by final glazing treatment or chairside polishing procedure. The purpose of this study was to compare the surface roughness among self-glazed, overglazed and polished porcelain with various polishing kit, and to detect which phase of polishing is optimal in clinic. Specimens were fabricated with Vita VMK porcelain. The surface treatment of each group was performed as follows. Group 1 : overglazing treatment Group 2 : self-glazing treatment Group 3 : polishing with the Truluster Polishing System for Porcelain(Brasseler, U.S.A.) Group 4 : polishing with the Exa Cerapol Adjustment kit (Edenta dental products, Switzerland) followed by finishing with diamond-filled polishing paste Group 5 : polishing with the Shofu Porcelain Adjustment kit (Shofu inc., Japan) followed by finishing with diamond-filled polishing paste. At each polishing steps, the measurement of Ra and Rq values were performed, and the surface was examined by scanning electron microscope. The results were as follows : 1. Overglazing treatment brought smoother surface than self-glazing treatment. 2. Polishing systems without porcelain polishing paste did not make better result than self-glazing treatment. 3. Polishing system with porcelain polishing paste made similar result to overglazing treatment. 4. Applying diamond-filled polishing paste after using polishing system which has no porcelain polishing paste produced surface as smooth as overglazing treatment does.

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Comparison on the Physical & Chemical Characteristics in Surface of Polished Wafer and Epi-Layer Wafer (Polished Wafer와 Epi-Layer Wafer의 표면 처리에 따른 표면 화학적/물리적 특성)

  • Kim, Jin-Seo;Seo, Hyungtak
    • Korean Journal of Materials Research
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    • v.24 no.12
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    • pp.682-688
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    • 2014
  • Physical and chemical changes in a polished wafer and in $2.5{\mu}m$ & $4{\mu}m$ epitaxially grown Si layer wafers (Epilayer wafer) after surface treatment were investigated. We characterized the influence of surface treatment on wafer properties such as surface roughness and the chemical composition and bonds. After each surface treatment, the physical change of the wafer surface was evaluated by atomic force microscopy to confirm the surface morphology and roughness. In addition, chemical changes in the wafer surface were studied by X-ray photoemission spectroscopy measurement. Changes in the chemical composition were confirmed before and after the surface treatment. By combined analysis of the physical and chemical changes, we found that diluted hydrofluoric acid treatment is more effective than buffered oxide etching for $SiO_2$ removal in both polished and Epi-Layer wafers; however, the etch rate and the surface roughness in the given treatment are different among the polished $2.5{\mu}m$ and $4{\mu}m$ Epi-layer wafers in spite of the identical bulk structural properties of these wafers. This study therefore suggests that independent surface treatment optimization is required for each wafer type, $2.5{\mu}m$ and $4{\mu}m$, due to the meaningful differences in the initial surface chemical and physical properties.

An Experimental Study on the Effect of Concrete Surface Treatment Methods on the Bond Strength of Metal Spray Coating (콘크리트 표면처리 방법이 콘크리트 표면 금속용사 피막의 부착강도에 미치는 영향에 관한 실험적 연구)

  • Park, Jin-Ho;Kim, Sang-Yeol;Lee, Han-Seung
    • Journal of the Architectural Institute of Korea Structure & Construction
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    • v.36 no.1
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    • pp.147-154
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    • 2020
  • The exterior finishing of reinforced concrete buildings is one of the important factors to prevent durability and prevent natural environment or disaster such as temperature, snow, wind, rain from the outside as well as external design of buildings. Finishing methods can be divided into wet and dry methods. The wet method using paint is relatively easy to construct, but it requires repair and reinforcement every 1 to 5 years and requires a lot of LCC for maintenance. Finishing method using panel has good durability, but it is difficult to install and expensive. Therefore, in this paper, we evaluate the bond strength for the application of the metal spray method in order to overcome the problems of existing methods. Experimental results show that the sandblast + surface roughness agent(S-R(Y)) has a roughness of 41.16 ㎛ and the bond strength is about 3.19 MPa, which is the highest bond strength. In addition, the grinding + surface roughness agent(G-R(Y)) application showed roughness of about 36.59 ㎛ and secured the bond strength performance of 2.94 MPa.

Relationship between Surface Roughness and Crystal size of Li2O-Al2O3-SiO2(LAS) Glass-Ceramic System (Li2O-Al2O3-SiO2(LAS)계 결정화유리에서 결정크기와 표면조도 관계)

  • Kim Yu Jin;Hwang Seong Jin;Kim Hyung Sun
    • Korean Journal of Materials Research
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    • v.14 no.7
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    • pp.505-510
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    • 2004
  • The glass-ceramic based on LAS($Li_{2}O-Al_{2}O_3-SiO_{2}$) system was observed using SEM(Scanning Electric Microscopy) and AFM(Atomic Force Microscopy) and it was expected to get a correlation between the crystal size and the surface roughness through the result. At heat treatment conditions (the nucleation: $740\~800^{\circ}C$, the crystal growth: $900\~1150^{\circ}C$), the crystal size was increased from 72 to 450 nm so that the mean of surface roughness was also risen from 0.8 to 6.3 nm. Based on the results, the surface roughness of glass-ceramic is controlled by the factors, crystal size, crystallines, and the condition of heat treatment.

Investigation of effect of zirconia on osseointegration by surface treatments (지르코니아 표면처리가 골유착에 미치는 영향)

  • Jeong, Jin-Woo;Song, Young-Gyun
    • Journal of Dental Rehabilitation and Applied Science
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    • v.37 no.1
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    • pp.23-30
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    • 2021
  • Purpose: The aim of this study was to investigate effect of zirconia on osseointegration and Surface appearance by surface treatments using various acid solution. Materials and Methods: The prepared zirconia disks were treated with hydrofluoric acid solution and photo-assisted etching under various condition. The surface was analyzed by SEM and the surface roughness was analyzed by using surface profiler. The osteogenic effect of MC3T3-E1 cells was assessed via fluorescent staining observation and reverse transcriptase-polymerase chain reaction (RT-PCR). Results: Various roughness were obtained according to the surface treatment method. The surface roughness increased in the group treated with hydrofluoric acid solution, but that had week network structure. In the method using photo-assisted etching, the surface roughness increased in micro units. Cell reaction showed better results in the photo-assisted etching group than in the hydrofluoric acid-treated group (P < 0.05). And it showed even osteoblastic cell distribution in photo-assisted etching group. Conclusion: As a result, the photo-assisted etching method is more effective than the simple acid solution treatment for zirconia treatment for osseointegration.

Adhesion and Electrical Performance by Plasma Treatment of Semiconductive Silicone Rubber (반도전성 실리콘 고무의 플라즈마 표면처리에 따른 접착특성과 절연성능)

  • Hwang, Sun-Mook;Lee, Ki-Taek;Hong, Joo-Il;Huh, Chang-Su
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.18 no.5
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    • pp.450-456
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    • 2005
  • In this paper, the effect of adhesion properties of semiconductive-insulating interface layer of silicone rubber on electrical properties was investigated. The modifications produced on the silicone surface by oxygen plasma were accessed using ATR-FTIR, contact angle and Surface Roughness Tester. Adhesion was obtained from T-peel tests of semiconductive layer haying different treatment durations. In addition, ac breakdown test was carried out for elucidating the change of electrical property with duration of plasma treatment. From the results, the treatment in the oxygen plasma produced a noticeable increase in surface energy, which can be mainly ascribed to the creation of O-H and C=O. It is observed that adhesion performance was determined by surface energy and roughness level of silicone surface. It is found that at dielectric strength was increased with improving the adhesion between the semiconductive and insulating interface.

The SPM Study on the Change of Titanium Surface Roughness following Airpowder Abrasive and Application Time of Citric Acid (공기-분말 연마와 구연산의 적용시간에 따른 임프란트 표면 거칠기의 변화에 관한 주사탐침현미경적 연구)

  • Park, Min-Seo;Chung, Chin-Hyung;Lim, Sung-Bin
    • Journal of Periodontal and Implant Science
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    • v.30 no.4
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    • pp.821-836
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    • 2000
  • The Peri-implantitis causes inflammation of periodontal tissue and bone loss. It contaminates surface of implants. Therefore, guided bone regeneration has been used for the treatment of this disease. For the reosseointegration of the exposed surface, various mechanical and chemical methods have been used for cleaning and detoxication of implant surface. Among these methods, air-powder abrasive and oversaturated citrate are known to be most effective. However, these treatments may deform implant surface. In this research, changes of surface roughness they were examined. 10 experimental machined titanium cylinder models were fabricated to be used for control groups. Each of them was air powder abraded for 1 minute and they were named group 1. And then, group 1 were burnished with cotton pellets soaked with citrate for 30 seconds(Group 2), 1 minute(Group 3), 3 minutes(Group 4), and 5 minutes(Group 5) burnishing were applied for grouping respectively. Each group were examined with SPM, and their surface roughness were measured and analyzed. 1. Surface roughness of titanium decreased when it was air-powder abraded for 1 minute. It was statistically significant. 2. When Air-powder abraded titanium were treated with citrate for 3 minutes, Their surface roughness was the lowest. Titanium treated for 1 minute was the second lowest and 30 seconds was the third and titanium burnished for 5 minutes was the highest. 3. Surface roughness of titanium which was treated with citrate was decreased till 3 minutes, which was statistically significant. There was no statistical significance from 30 seconds to 1 minute and from 1 minute to 3 minutes, and there was statistical significance from 30 seconds to 3 minutes. 4. Oxide layer was formed when titanium is exposed to air, and it was removed when air-powder abraded. It was made when treated with citrate. It is thought that citrate treatment is necessary after the air-powder abrasion, and 1 minute is clinically and qualitatively adequate for burnishing time of citrate.

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Study on Efficiency improvement of OLEDs by surface treatment of $UV/O_3$ ($UV/O_3$ 표면처리에 따른 OLEDs 효율 향상에 관한 연구)

  • Jang, Yoon-Ki;Kim, Byoung-Sang;Kwon, Oh-Kwan;Kwon, Young-Soo
    • Proceedings of the KIEE Conference
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    • 2005.11a
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    • pp.142-144
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    • 2005
  • Main purpose of this study is a improved efficiency of Organic light emitting diodes(OLEDs) concerning $UV/O_3$ treatment. We investigated the efficiency of OLEDs by $UV/O_3$ treatment of ITO surface. We measured current density-voltage, luminance-voltage characteristics in different $UV/O_3$ treatment time and observed ITO surface roughness by using AFM(Atomic Force Microscope). The fundamental structure of the OLEDs was $ITO/NPB/Alq_3/LiF/Al$. We performed $UV/O_3$ treatment and found that $UV/O_3$ treatment enhanced the performance of OLEDs. We also found that change of surface roughness according to difference time a $UV/O_3$ treatment

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The Effect of Coloring Condition on the Surface Characteristic of 304 Stainless Steel (304 스테인리스강의 착색 처리 조건이 표면 특성에 미치는 영향)

  • Kim, Ki-Ho
    • Journal of the Korean institute of surface engineering
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    • v.44 no.5
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    • pp.220-225
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    • 2011
  • 304 stainless steel plate was colored by hot dip and electrochemical treatment in a solution containing sulphuric and chromic acids. In the process, treatment variables such as operating time and methode were changed. The surface characteristics that changed by the treatment of the samples such as surface composition, oxide film thickness, color, surface roughness and reflectivity were studied. Surface composition was varied as follows. Fe was decreased, but Cr and O were increased. Ni was increased until 20 min, but reveals decreasing tendency as time passed after that. These means the surface film becomes chrome rich oxide phase as the treatment times increase. The thickness of film was about 220 nm at 30 min by dip treatment and it reduced as the treatment times increased. On the other hand, the thickness was about 150 nm at 10 min by electrochemical method and it doesn't increased with time. Surface color changed from metallic white of the base plate to gray, black, red, and green-blue, gradually, as the treating time increased. The reflectivity of colored surface measured by UVVIS-NIR spectrophotometer was reduced from max 38% of basis metal to min 3.5%.

Comparison of the effect of hand instruments, an ultrasonic scaler, and an erbium-doped yttrium aluminium garnet laser on root surface roughness of teeth with periodontitis: a profilometer study

  • Amid, Reza;Kadkhodazadeh, Mahdi;Fekrazad, Reza;Hajizadeh, Farzin;Ghafoori, Arash
    • Journal of Periodontal and Implant Science
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    • v.43 no.2
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    • pp.101-105
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    • 2013
  • Purpose: The present study aimed to measure root surface roughness in teeth with periodontitis by a profilometer following root planning with ultrasonic and hand instruments with and without erbium-doped yttrium aluminium garnet (Er:YAG) laser irradiation. Methods: Sixty single-rooted maxillary and mandibular teeth, extracted because of periodontal disease, were collected. The crowns and apices of the roots were cut off using a diamond bur and water coolant. The specimens were mounted in an acrylic resin block such that a plain root surface was accessible. After primary evaluation and setting a baseline, the samples were divided into 4 groups. In group 1, the samples were root planned using a manual curette. The group 2 samples were prepared with an ultrasonic scaler. In group 3, after scaling with hand instrumentation, the roots were treated with a Smart 1240D plus Er:YAG laser and in group 4, the roots were prepared with ultrasonic scaler and subsequently treated with an Er:YAG laser. Root surface roughness was then measured by a profilometer (MahrSurf M300+RD18C system) under controlled laboratory conditions at a temperature of $25^{\circ}C$ and 41% humidity. The data were analyzed statistically using analysis of variance and a t-test (P<0.05). Results: Significant differences were detected in terms of surface roughness and surface distortion before and after treatment. The average reduction of the surface roughness after treatment in groups 1, 2, 3, and 4 was 1.89, 1.88, 1.40, and 1.52, respectively. These findings revealed no significant differences among the four groups. Conclusions: An Er:YAG laser as an adjunct to traditional scaling and root planning reduces root surface roughness. However, the surface ultrastructure is more irregular than when using conventional methods.