scholarly journals Biomechanical evaluation between orthodontic attachment and three different materials after various surface treatments: A three-dimensional optical profilometry analysis

2019 ◽  
Vol 89 (5) ◽  
pp. 742-750
Author(s):  
İrem Kurt ◽  
Zafer Cavit Çehreli ◽  
Ayça Arman Özçırpıcı ◽  
Çağla Şar

ABSTRACT Objectives: To determine the best bonding method of orthodontic attachment among monolithic zirconia, feldspathic porcelain, hybrid porcelain, and the impact of surface-conditioning methods using a three-dimensional optical profilometer after debonding. Materials and Methods: 56 feldspathic porcelain, 56 monolithic zirconia, and 56 hybrid porcelain samples were divided into four surface treatment subgroups: (1) hydrofluoric (HF) acid etch + silane, (2) Al2O3 sandblasting + silane, (3) silicoating (SiO2), and (4) diamond bur + silane. The specimens were tested to evaluate shear bond strength (SBS). Residual composite was removed after debonding. Three-dimensional white-light interferometry was used to obtain quantitative measurements on surface roughness. Results: The highest SBS value was found for the HF acid–etched feldspathic porcelain group. The average surface roughness values were significantly higher in all material groups in which diamond bur was applied, while roughening with Cojet provided average surface roughness values closer to the original material surface. Conclusions: Variations in structures of the materials and roughening techniques affected the SBS and surface roughness findings.

Author(s):  
MAHMUT ÇELIK ◽  
HAKAN GÜRÜN ◽  
ULAŞ ÇAYDAŞ

In this study, the effects of experimental parameters on average surface roughness and material removal rate (MRR) were experimentally investigated by machining of AISI 304 stainless steel plates by magnetic abrasive finishing (MAF) method. In the study in which three different abrasive types were used (Al2O3, B4C, SiC), the abrasive grain size was changed in two different levels (50 and 80[Formula: see text][Formula: see text]m), while the machining time was changed in three different levels (30, 45, 60[Formula: see text]min). Surface roughness values of finished surfaces were measured by using three-dimensional (3D) optical surface profilometer and surface topographies were created. MRRs were measured with the help of precision scales. The abrasive particles’ condition before and after the MAF process was examined and compared using a scanning electron microscope. As a result of the study, the surface roughness values of plates were reduced from 0.106[Formula: see text][Formula: see text]m to 0.028[Formula: see text][Formula: see text]m. It was determined that the best parameters in terms of average surface roughness were 60[Formula: see text]min machining time with 50[Formula: see text][Formula: see text]m B4C abrasives, while the best result in terms of MRR was taken in 30[Formula: see text]min with 50[Formula: see text][Formula: see text]m SiC abrasives.


Author(s):  
Muhammad Hasibul Hasan ◽  
Shugata Ahmed ◽  
Ron Voldman ◽  
Mirt Mehany

The ability to use different parameters and finishing techniques in fused deposition modelling (FDM) depends largely on part geometries, materials, printing processes like Z-resolution and post processing to some extent. Low quality poor surface finish due to layer ovality, improper Z-resolution parameter selection and fill of the empty shell in three-dimensional (3D) printing, results unexpected texture and appearance. An investigation is carried out on the effects of Z-resolution (0.15 mm to 0.40 mm) and Fill parameters on flat and curved surface objects manufactured using the FDM process. Moreover, post surface treatment was performed using acetone. It was found that average surface roughness increases with increasing Z-resolution. Solid Fill can create a smoother surface as oppose to Sparse Fill. Surface roughness improves significantly after post treatment with organic solvent acetone.


2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Mustafa Bozdemir

To know the impact of processing parameters of PA6G under different humidity conditions is important as it is vulnerable to humidity up to 7 %. This study investigated the effect of cutting parameters to surface roughness quality in wet and dry conditions. Artificial Neural Network (ANN) modeling is also developed with the obtained results from the experiments. Humidity condition, tool type, cutting speed, cutting rate, and depth of cutting parameters were used as input and average surface roughness value were used as output of the ANN model. Testing results showed that ANN can be used for prediction of average surface roughness.


2021 ◽  
Vol 13 (4) ◽  
pp. 168781402110118
Author(s):  
Zenan Chu ◽  
Tao Wang ◽  
Qiang He ◽  
Kai Zhao

To solve the problems of low processing efficiency and poor glass surface quality when using rare earth polishing powder to grind super-hard K9 glass. The potential, phase structure, surface morphology, and particle size distribution of the nano-rare earth polishing powder were characterized. Compare the evaluation indexes such as polishing efficiency, surface morphology, and contact angle after the polishing process is changed. The results of the comparative study show that the average surface roughness of the glass after heating ultrasonic polishing process is 0.9064 nm, the polishing rate reaches 0.748 μm/min, the average surface roughness of the glass without heating ultrasonic polishing process is 1.3175 nm, and the polishing rate reaches 0.586 μm/min, the ultrasonic assisted polishing process is superior to the conventional polishing process. The heating ultrasonic method provides experimental basis for precise and rapid processing.


2014 ◽  
Vol 627 ◽  
pp. 29-34 ◽  
Author(s):  
Vichaya Thammasing ◽  
Somkiat Tangjitsitcharoen

The purpose of this research is to develop the models to predict the average surface roughness and the surface roughness during the in-process grinding by monitoring the cutting force ratio. The proposed models are developed based on the experimentally obtained results by employing the exponential function with four factors, which are the spindle speed, the feed rate, the depth of cut, and the cutting force ratio. The experimentally obtained results showed that the dimensionless cutting force ratio is usable to predict the surface roughness during the grinding process, which can be calculated and obtained by taking the ratio of the corresponding time records of the cutting force Fy in the spindle speed direction to that of the cutting force Fz in the radial wheel direction. The multiple regression analysis is utilized to calculate the regression coefficients with the use of the least square method at 95% confident level. The experimentally obtained models have been verified by the new cutting tests. It is proved that the developed surface roughness models can be used to predict the in-process surface roughness with the high accuracy of 93.9% for the average surface roughness and 92.8% for the surface roughness.


2015 ◽  
Vol 2015 (DPC) ◽  
pp. 001928-001955
Author(s):  
Naoya Watanabe ◽  
Masahiro Aoyagi ◽  
Daisuke Katagawa ◽  
Tsubasa Bandoh ◽  
Takahiko Mitsui ◽  
...  

Three-dimensional integrated circuits (3D-ICs) using through silicon via (TSV) have been developed as an emerging technology that can lead to significant progress (1–4). Among various TSV processes, the via-middle process has potential for wide spread use because formation of small-sized TSVs is relatively easy in the via-middle process. However, TSV reveal process must be performed for electrical contact in the via-middle process. This TSV reveal process is important because it can influence the metal contamination and stacking yield of 3D-ICs. Conventionally, TSV reveal is performed by Si grinding and Si dry etching (5). A disadvantage of that method is the resultant TSV depth deviation, which can cause bonding failure during wafer/chip stacking. In (6), TSV leveling was performed by introducing a chemical mechanical polishing (CMP) step after deposition of the backside insulator. However, the revealed TSVs break during CMP step if they exceed a certain height. To overcome these problems, we developed a novel TSV reveal process comprising direct Si/Cu grinding and metal contamination removal (7,8). First, simultaneous grinding of Cu and Si was performed using a novel vitrified grinding wheel. In situ cleaning with a high-pressure micro jet and the inelastic porous structure of the grinding wheel suppressed the adhesion of Cu contaminants to the Si, and TSVs were leveled and exposed. Next, an electroless Ni-B film was deposited on the Cu surface of the TSVs. The Si was etched with an alkaline solution, whereas the Cu was protected by the Ni-B film. An insulator was deposited, and then the insulator on the top surface of the TSV was removed. We achieved the backside reveal of TSVs without TSV depth deviation and suppressed Cu contamination to less than 1e11 atoms/cm2. However, after direct Si/Cu grinding with an 8000 grit grinding wheel, the average surface roughness of Si was 5–10 nm, which is larger than that after chemical mechanical polishing (CMP). In this paper, we developed vitrified grinding wheels with very high grit numbers (#30,000 and #45,000) and present an improved version of our TSV reveal process. The average surface roughness of Si after Si/Cu grinding was approximately 3 nm for the 30,000 grit grinding wheel and 1 nm for the 45,000 grit grinding wheel. This value is equivalent to that after CMP. The improved process produced a uniform reveal of 4-um-diameter TSVs without TSV depth deviation and Cu contamination. The Cu contaminant concentration on Si region between TSVs was small (<3e10 atoms/cm2). This process will reduce the cost of the TSV reveal process and considerably improve the TSV yield.


2020 ◽  
Vol 10 (18) ◽  
pp. 6265
Author(s):  
Vasiliki Kamperidou ◽  
Efstratios Aidinidis ◽  
Ioannis Barboutis

The surface roughness constitutes one of the most critical properties of wood and wood veneers for their extended utilization, affecting the bonding ability of the veneers with one another in the manufacturing of wood composites, the finishing, coating and preservation processes, and the appearance and texture of the material surface. In this research work, logs of five significant European hardwood species (oak, chestnut, ash, poplar, cherry) of Balkan origin were sliced into decorative veneers. Their surface roughness was examined by applying a stylus tracing method, on typical wood structure areas of each wood species, as well as around the areas of wood defects (knots, decay, annual rings irregularities, etc.), to compare them and assess the impact of the defects on the surface quality of veneers. The chestnut veneers presented the smoothest surfaces, while ash veneers, despite the higher density, recorded the highest roughness. In most of the cases, the roughness was found to be significantly lower around the defects, compared to the typical structure surfaces, probably due to lower porosity, higher density and the presence of tensile wood. The results reveal that the presence of defects does not affect the roughness of the veneers and increases neither the processing requirements of the veneer sheets before finishing, nor the respective production cost of veneers and the veneer-based wood panels. The high utilization prospects of the examined wood species in veneer production, even those bearing various defects, is highlighted.


2019 ◽  
Vol 11 (7) ◽  
pp. 168781401983631 ◽  
Author(s):  
István Gábor Gyurika ◽  
Tibor Szalay

Automated stone manufacturing has undergone considerable development in recent years. Thanks to international research dealing with the cutting, sawing and grinding of different natural stones, processing time shortens and tool-life lengthens. However, the process of stone milling has not been extensively examined yet, primarily because of the novelty of this technology. The aim of the research described in this article is to examine how variable cutting speed affects the quality of workpiece edges while milling granite materials. For the research, sample surfaces were formed on five granite slabs with different average grain sizes using five cutting speed values. Afterwards, changes in the average surface roughness and average edge chipping rate were examined. From the research results, it can be concluded that, due to an increase in cutting speed, the average edge chipping rate will decrease until reaching a borderline speed. In the case of a higher cutting speed, the referent tendency cannot be ascertained. A statistical analysis conducted in the scope of this research showed that if a variable cutting speed is applied, then changes in the quality of the sample surface edge can be inferred from the development trends of average surface roughness.


2019 ◽  
Vol 1154 ◽  
pp. 91-101
Author(s):  
Eko Pujiyulianto ◽  
Suyitno

Electropolishing is an attractive method for surface smoothing of cardiovascular stent. This study investigated the effect of times of electropolishing on the surface characteristics both are upper surface and surface of the strut of cardiovascular stent after the by die sinking electrical discharge machining (EDM). The observed surface characteristics of the strut were recast layer, surface roughness and brightness. The weight analysis, and the reduction of the width strut were conducted. The recast layer was analyzed by optical microscope qualitatively, the surface roughness was measured by surface texture measuring instrument, the weight analysis and the reduction of width strut were calculated. The stent was made from steel AISI 316 L. The times which were used in the electropolishing were 3 minutes, 7 minutes, and 11 minutes. The experimental results show that the time for smoothing and brightening of stent at room temperature and low voltage 5 V is 7 minutes. The times affect the upper and EDM surface roughness, the weight of stent and the width of strut. The results show that increasing of times, than the value of surface roughness, the weight of stent and the width of strut will decrease, and vice versa. The average surface roughness of EDM surface after electropolishing is in the range of 3.49 – 1.62 µm. The average surface roughness of upper surface after electropolishing is in the range of 0.55-0.22 µm. The weight analysis show that the loss of weight is in the range of 0.12-1.12 %, and the reduction of width strut is in the range of 11.02 – 69.3 %.


2005 ◽  
Vol 16 (1) ◽  
pp. 39-44 ◽  
Author(s):  
Silvia Helena Barbosa ◽  
Régia Luzia Zanata ◽  
Maria Fidela de Lima Navarro ◽  
Osvaldo Benoni Nunes

This study examined the average surface roughness (Ra, µm) of 2 microfilled (Durafill and Perfection), 1 hybrid (Filtek Z250) and 2 packable composite resins (Surefil and Fill Magic), before (baseline) and after eight different finishing and polishing treatments. The surface roughness was assessed using a profilometer. Ten specimens of each composite resin were randomly subjected to one of the following finishing/polishing techniques: A - carbide burs; B - fine/extrafine diamond burs; C - Sof-Lex aluminum oxide discs; D - Super-Snap aluminum oxide discs; E - rubber polishing points + fine/extrafine polishing pastes; F - diamond burs + rubber polishing points + fine/extrafine polishing pastes; G - diamond burs + Sof-Lex system; H - diamond burs + Super-Snap system. Data were analyzed using two-way ANOVA and Tukey's HSD test. Significant differences (p<0.05) were detected among both the resins and the finishing/polishing techniques. For all resins, the use of diamond burs resulted in the greatest surface roughness (Ra: 0.69 to 1.44 µm). The lowest Ra means were obtained for the specimens treated with Sof-Lex discs (Ra: 0.11 to 0.25 µm). The Ra values of Durafill were lower than those of Perfection and Filtek Z250, and these in turn had lower Ra than the packable composite resins. Overall, the smoothest surfaces were obtained with the use the complete sequence of Sof-Lex discs. In areas that could not be reached by the aluminum oxide discs, the carbide burs and the association between rubber points and polishing pastes produced satisfactory surface smoothness for the packable and hybrid composite resins, respectively.


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