Type Of Surface Treatment Research Articles

Protective chromate-free conversion coatings on AMg6 aluminum alloy with different types of surface treatment

Protective chromate-free conversion coatings on AMg6 aluminum alloy with different types of surface treatment

Comparison of shear bond strength of metal orthodontic brackets bonded to a CAD/CAM prosthetic provisional material after the use of a self-adhesive resin cement versus a light adhesive paste and different surface conditioning protocols: An in vitro study

Adult orthodontic treatment has been increasingly popular, and brackets may need to be bonded to provisional crowns, including CAD/CAM crowns. The use of self-adhesive resin cement or light adhesive paste have been suggested with different surface conditioning protocols to improve the adhesion to CAD/CAM PMMA provisional crowns. Objective To determine and compare the in vitro shear bond strength (SBS) of metal brackets bonded to a provisional prosthetic CAD/CAM material after the use of different adhesive cements and surface conditioning protocols. One hundred twenty Telio® CAD specimens were manufactured in 12 groups (n=10). Each specimen was bonded to a metal bracket and divided according to adhesive technique (3M™Transbond™ XT Light Cure Paste or 3M™RelyX™ U200) surface treatment (macroretentions) and the use of silane. Half of the specimens were thermocycled (5000 cycles, 5°C/55°C water baths). The SBS test was carried out using a shear bond strength tester, and the type of adhesive failure was determined by means of the adhesive remnant index. The data were analysed with the Mann-Whitney test (α=0.05). Statistically significant differences (P<0.001) in SBS were found among the groups. The group with macroretentions, silane, and not thermocycled was the one that obtained the highest average value (17.31±4.89MPa). The lowest average value was the group without macroretentions, without silane, and thermocycled (3.4±3.37MPa). The shear bond strength of brackets to provisional prosthetic CAD/CAM materials depended on the type of adhesive, surface treatment, and aging by thermocycling.

Influence of Abrasive Treatment on a Transformation of Zirconium Oxide Used in Dental Prosthetics.

Zirconium oxide is a ceramic most often used in the field of dentistry for permanently cementing the substructures of prosthetic restorations in patients. The surface of zirconium oxide should be prepared properly because in the next stage it must be covered with porcelain. The success of prosthetics treatment depends on various factors, but it has been reported that the transformation of zirconium oxide plays a key role. The purpose of the research was to investigate the effect of abrasive blasting on the transformation of zirconium oxide. The research has shown that this type of surface treatment causes the transformation of the tetragonal phase into a monoclinic one. The samples were examined using X-ray diffraction (XRD). The study confirmed the assumption.

Intensification of heat transfer in the zone of the thermosyphon evaporator when changing the boiling surface shape

In present paper the influence of the boiling surface treatment types of thermosyphon evaporator on the heat transfer coefficient was studied. An experimental setup «Loop thermosyphon with replacing lower part of the evaporator» has been developed and assembled. This feature makes it easy to replace samples with various surface modifications as the lower part of the evaporator. The description of the experimental setup, equipment and research methods is given. Heat transfer coefficients for the samples at various applied thermal loads (from 5 to 200 W) were calculated. In case of flat aluminum plate (boiling surface) concentric grooves and uneven coating of aluminum oxide particles, an increase of the heat transfer coefficient from h1= 5760 W/(m2·K) to h2= 28339 W/(m2·K) at the supplied heat flux density q = 250 kW/m2was observed. The heat transfer coefficient for a sample without concentric grooves, but with an uneven coating of aluminum oxide particles was h3= 16952 W/(m2·K) at q = 250 kW/m2. Results of the study can be used for further increase of thermosyphon evaporator efficiency.

Strength and failure mechanism of single-lap magnesium-basalt fiber metal laminate adhesively bonded joints: Experimental and numerical assessments.

A quick literature search reveals the significant lack of data and information concerning magnesium-to-magnesium bonded joints as well as fiber-metal laminates (FMLs) made with magnesium alloys. Therefore, a systematic series of experimental and numerical investigations are carried out to assess the performance of single-lap joints mating FML adherends. The primary goal is to better understand the effects of geometrical and material parameters that influence the performance of magnesium-to-magnesium joints. The FML adherends used in this study consist of basalt natural fiber-epoxy laminate sandwiched in between thin sheets of magnesium alloys, which were subsequently adhesively bonded using a room-cured epoxy resin. The effects of two types of surface treatments, namely, “sandblasting” and “sandblasting with resin coating” on the bond strength and failure mechanism of the adhesively bonded joints (ABJs) are investigated. A 3D numerical model developed to simulate the response of the joints subjected to quasi-static lap-shear tests. This model, which accounts for the material and geometrical nonlinearity in the joints, is used to perform a parametric analysis for establishing the optimal overlap bond length. The distributions of the shear and peel stresses in the overlap region and the effects of adhesive thickness on the performance of the joints are systematically examined. The comparison of the experimental data and numerical results confirms the robustness and cost-effectiveness of the numerical model in predicting the response of such single-lap ABJs.

Synthesis and characterization of wood flour modified by graphene oxide for reinforcement applications

Abstract The performance of thermoplastic polyurethane (TPU) reinforced with natural fibers can be tailored through a suitable choice of the fibers nature or the type of surface treatment applied to them. The present work deals with the improvement of the interfacial properties of natural fibers, namely wood flour (WF) by the introduction of graphene oxide (GO), which may easily disperse on the WF surface to provide hybrid fibers (WF-GO). The latter were then used as reinforcement of a TPU matrix at different ratios of 1, 3 and 5 wt%. The different samples were characterized by FTIR and RAMAN spectroscopies, XRD, SEM and TGA to confirm the structure, morphology and the thermal stability of the prepared hybrid fibers as well as their composites (TPU/WF-GO). SEM micrographs revealed that the surface treatment applied to WF, the distribution of GO sheets on the fiber interface, and the dispersion of (WF-GO) on the polymer matrix were successfully carried out. The thermal stability of the TPU-base composites increased with the increase of WF-GO content from 325 °C for the pure TPU matrix to 343 °C for the composite reinforced by 5% of (WF-GO). In addition, the results confirmed that the incorporation of GO into WF led to a significant improvement in the mechanical properties of the TPU-based composites, with an improvement in strength from 10.9 MPa to 19 MPa.

Flexural Strength of Concrete Beam Reinforced with CFRP Bars: A Review.

Conventional reinforced concrete (RC) structures are commonly associated with the corrosion of steel reinforcement. The application of carbon fiber reinforced polymer (CFRP) bars as flexural reinforcement has become a new promising option. This paper presents a state-of-the art flexural strength on concrete beams reinforced with CFRP bars. Concrete compressive and CFRP bar tensile strain, reinforcement ratio, types of surface treatment on CFRP bar and concrete compressive strength were identified as aspects of behavior. Significant findings in the literature had manifested all aspects of behavior that were affecting the flexural strength, deflections and crack characteristics of CFRP RC beams. In addition, the experimental result on 98 specimens of CFRP RC beams from the literature show that ACI 440.1R-15 and CSA S806-12 standards underestimate the ultimate flexural moment capacity of CFRP RC beams. On the other hand, Kara and Ashour predictions are more accurate with the experimental values. Moreover, hotspot research topics were also highlighted for further considerations in future studies.

Effect of surface treatment, ferrule height, and luting agent type on pull-out bond strength of monolithic zirconia endocrowns.

To evaluate the effect of different surface treatments, ferrule heights, and luting agents on the pull-out bond strength (PBS) of computer-aided design/computer-aided manufacturing (CAD-CAM) monolithic endocrowns. After endodontic treatment and preparation for two endocrown designs (ferrule height 0 mm or 2 mm), CAD-CAM monolithic zirconia endocrowns were fabricated for 80 mandibular molars. Each endocrown design group was then divided on the basis of surface treatment into two groups: half were air-abraded and half were air-abraded/laser-irradiated. Then, all treated groups were further divided into two subgroups (n = 10) and cemented to teeth with either a 10-methacryloyloxydecyl dihydrogen phosphate (MDP)-containing resin luting agent (Panavia SA) or a combination of MDP-containing primer and MDP-free resin luting agent (Monobond Plus/Multilink Automix). PBS was measured with a universal test machine after simulated chewing and thermocycling. Three-way ANOVA and the post-hoc Bonferroni test were used for statistical analysis. PBS was significantly associated with type of surface treatment, type of luting agent, and ferrule height. Air-abraded/laser-irradiated endocrowns with a 2-mm ferrule that were cemented with Monobond Plus/Multilink Automix had the highest PBS (P < 0.05). Surface treatment with air abrasion/laser irradiation, presence of a ferrule, and priming with an MDP-containing primer increased the PBS of monolithic zirconia endocrowns.

Comparative evaluation of adhesion of glass fiber post to the root dentin after surface treatment of post and using universal bonding agent: An in vitro study.

The purpose of the study is the evaluation and comparison of surface roughness and bond strength of glass fiber post (GFP) after different types of surface treatment and the application of a universal bonding agent. Forty GFPs were divided into four groups based on surface treatment: Group I, silane coupling agent application for 60 s; Group II, air abrasion with 30 μm silicon dioxide powder particles in 2.5 bar pressure from 2 cm distance for 10 s, followed by silane coupling agent application; Group III, 9% hydrofluoric acid application for 10 s, rinsed and air-dried, followed by silane coupling agent application; and Group IV, silane coupling agent application, followed by universal bonding agent application. Surface roughness evaluation is done by a profilometer. All posts were cemented in the root of the maxillary central incisor with resin cement. After that, root was placed in an acrylic mold, and the external end part of the post was mounted on another acrylic mold. Pull-out bond strength was measured by a universal testing machine. Highest surface roughness and bond strength values were found in Group II. Pretreatment of GFP increases the surface roughness of post as well as bond strength of post to root dentin. There is a correlation between surface roughness and bond strength. However, the use of only universal bonding agent also showed comparable pull-out bond strength of GFP, which means only use of universal bonding agent also a new alternative as pretreatment of GFP and helps in increase in bond strength.

Chemical Surface Treatments on aluminium films to prepare FML (Al-PP laminates)

In this work, different type of surface treatments on aluminium films have been performed. The changes that these treatments produce in the nature, composition, functionality, morphology and free surface energy on the aluminium surfaces will be analyzed. First treatment has been performed in two steps, the first one consists on activating the aluminium surface with sodium metoxyde in methanol and the time and treatment conditions on the nature of the formed surface will be studied. The second treatment has been performed in three steps, so between the activation step and the sylanization, an intermediate treatment has been done in order to try to insert a polymer by &quot;in situ&quot; polymerization on the aluminium surface. Those treated aluminium film surfaces have been characterized using infrared spectroscopy by Fourier transform (FTIR), contact angle measurement, surface energy determination and Dynamic Mechanic Thermal Analysis (DMTA).

A comprehensive review on bonding between monolithic ceramics and tooth structure with different adhesive agents.

Reliable bonding between the prepared tooth and monolithic ceramics can be achieved by various luting agents available on the market. The selection of luting agent and cementation technique plays an important role in the success of the restoration. With the advent of resin-based adhesive systems as luting agents, clinicians' perspectives have changed to a more conservative approach. Recent systems, chemically adhere athe crowns to the prepared tooth structure showing higher bond strength. To reach the aesthetic demands of the patients, all-ceramic restorations were considered over metal-ceramic crowns. Few all-ceramic crowns are brittle, the strength is dependent on the chemical structure and method of fabrication. While some all-ceramic restorations gain strength after cementation. Thus, the choice of luting agent used in cementing all-ceramic crowns is crucial. Even though many luting agents are being introduced no single luting agent fulfilled all the requirements. Among them, adhesive cements showed greater bond strength and enhanced the retention of minimal preparation, which are less retentive. Traditional non-adhesive agents can be used in retentive preparations that bond through mechanical means rather than the chemical bond seen in newer adhesive cements. Also, surface treatments of zirconia showed greater bond strengths irrespective of the luting agent being used. These include air abrasion, acid etching, applying silane couplers, and primers that increase the surface area for adhesion. The use of all-ceramic restorations, the need for surface treatments, types of surface treatments, adhesion and adhesive agents, and evidence from current in vitroresearch on monolithic ceramics and tooth adhesion were all discussed in this review.

Natural teeth wear opposite to glazed and polished ceramic crowns: A systematic review

It is a major concern to select a proper ceramic with acceptable strength and esthetic and minimum antagonist wear. Therefore, different ceramics were introduced to obtain these advantages with various surface treatments. The aim of this study is to evaluate and report the wear behavior of polished and glazed feldspathic and zirconia crowns in published articles up to 2020. Five electronic databases which were used in this research were MEDLINE (via PubMed), Web of Science, Cochrane Library, Embase, and Scopus from the starting date of databases to January 2020. The Keywords "zirconia," "feldspathic," "dental ceramic," "enamel," "Y-TZP," "wear," "glazed," and "polished" were used. English articles were selected in this paper. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement was used as a reporting template as much as possible. Among the initially 133 articles, 59 duplicated articles were removed, and finally, 52 articles were screened and among them, only 16 articles remained for full-text regaining. The results showed that zirconia had significantly less antagonist wear than feldspathic groups, and polishing had less enamel wear than other types of surface treatment like glazing. Only one study showed that glazed zirconia can have more antagonist wear than feldspathic porcelain. Monolithic zirconia had less enamel wear than conventional zirconia and low-fusing feldspathic porcelain showed lower antagonist wear in comparing with other types of feldspathic porcelains.

The effect of nonthermal argon plasma surface treatment on the fracture resistance of monolithic zirconia restorations containing tetragonal and cubic grains.

The aim of this study was to investigate the effect of nonthermal argon plasma (NP) surface treatment on the fracture resistance of monolithic zirconia restorations with different microstructures. Twenty restorations were prepared from each of two tetragonal and two cubic zirconia materials (80 restorations in total). The restorations were then divided into two subgroups (n = 10) for each material according to the surface treatment applied: air abrasion or NP. The surface topography of the treated groups was examined using a scanning electron microscope. All restorations were fixed to metal dies with resin cement, subjected to thermal cycling, and then underwent fracture resistance testing with a universal testing device. Two-way ANOVA and Bonferroni tests were used for statistical analysis of the data (α = 0.05). The type of surface treatment and the type of zirconia material were shown to significantly affect the fracture resistance of the restorations. The air-abraded groups showed significantly higher fracture resistance (N) than the NP groups (P < 0.001). The results of this study suggest that air abrasion surface treatment has a more favorable effect on the fracture resistance of tetragonal and cubic zirconia restorations than NP surface treatment.

Comparative Effect of two Types of Surface Treatments on Shear Bond Strength of New Composite to Old Composite.

Statement of the Problem: Composite restoration failures may occur because of different factors. In these situations, the repair of a composite restoration has many advantages over replacement such as saving time, lower cost, and lower risk of excessive removal of sound tooth structure and subsequent pulp exposure.Purpose: The purpose of this in vitro study was to evaluate the effects of two surface treatments on shear bond strength (SBS) of new composite to old composite.Materials and Method: In this in vitro study, 60 composite discs were fabricated using a plexiglass mold measuring 4 mm in thickness and 7 mm in diameter, and were randomly divided into three groups (n=20). In group 1, the bonding procedure was done with no modification. After roughening of one surface in all remaining samples, chloroform (CHCl3) was applied on the surface of samples in group 2 and phosphoric acid 35% was applied on the surface of the samples in group 3. PermaSeal was then applied in all samples and new composites were bonded to the surface. The samples were stored in distilled water for one week and were then subjected to 500 thermal cycles and shear bond strength between two layers of composite and mode of failures were evaluated.Results: The lowest and the highest SBS values of repair composite to old composite were noted in groups 3 and 1, respectively and this difference was statistically significant (p< 0.05).The difference between groups 1 and 2 was not significantly different (p= 0.197). The mode of failure was mixed in all samples of groups 2 and 3 and cohesive in group 1.Conclusion: After grinding, the surface treatment with phosphoric acid did not increase the SBS of new composite to old composite, while chloroform increased the SBS almost to the level of the baseline in control group.

Surface Treatment and Bioinspired Coating for 3D-Printed Implants.

Three-dimensional (3D) printing technology has developed rapidly and demonstrates great potential in biomedical applications. Although 3D printing techniques have good control over the macrostructure of metallic implants, the surface properties have superior control over the tissue response. By focusing on the types of surface treatments, the osseointegration activity of the bone–implant interface is enhanced. Therefore, this review paper aims to discuss the surface functionalities of metallic implants regarding their physical structure, chemical composition, and biological reaction through surface treatment and bioactive coating. The perspective on the current challenges and future directions for development of surface treatment on 3D-printed implants is also presented.

Effect of different types of substrate surface treatments on the graphene device performance

Graphene–substrate interface is very crucial for analyzing graphene device performance. In this article, we have shown how the graphene device performance got affected because of different types of substrate surface treatment techniques used before graphene transfer. For fabrication of graphene devices, monolayer chemical vapor deposition (CVD) graphene was transferred onto SiO2 grown thermally on Si substrate. Forming gas annealed SiO2/Si shows better device performance as compared with as‐grown SiO2 on Si substrate. A further effect of oxygen plasma and argon plasma cleaning of SiO2 surface before graphene transfer was investigated. Forming gas annealing improves the performance and plasma treatment degrade the graphene devices' performance.

Surface Treatments of Coffee Husk Fiber Waste for Effective Incorporation into Polymer Biocomposites.

Natural lignocellulose fibers have been extensively investigated and applied as a reinforcement of polymer composites in industrial applications from food packing to automotive parts. Among the advantages of natural fibers stands their relatively low cost and sustainable characteristics. These are accentuated in the case of residual fibers such as those obtained from coffee husks, an agribusiness waste, usually burnt or disposed into the environment. As composite reinforcement, hydrophilic natural fibers display adhesion problems to the most hydrophobic polymer matrices. This adhesion might be improved with distinct types of fibers surface treatments. In the present work, the effectiveness of three surface treatments applied to coffee husk fiber wastes (CHFW) were investigated, aiming to improve the tensile performance of castor oil-based polyurethane (COPU) biocomposites. The effects of treatments associated with (i) chemical with sodium hydroxide, (ii) physical by temperature and pressure and hydrothermic treatment, and (iii) biological by fermentation with Phanerochaete Chrysosporium fungus were evaluated by means of Fourier transformed infrared spectroscopy, X-ray diffraction, thermal analyses and morphology by scanning electron microscopy for different concentration of NaOH, different hydrothermic times at 121 °C/98 kPa and exposition to P. chrysosporium. The most effective treatment was the hydrothermal one at 121 °C and 98.06 kPa for 30 min. Preliminary tensile tests were performed in COPU biocomposites reinforced with 20% CHFWs subjected to the optimized conditions for each distinct type of treatment. The results indicated that the hydrothermal treatment promoted significant enhancement in the fiber/matrix interfacial bond, increasing the tensile strength up to 60% compared to COPU reinforced with in natura CHFWs fibers. It is important to mention that these composites can be applied as plastic wood for household items’ internal parts and in the automobile industry.

Experimental diagnostic and choice of technological parameters of ion nitriding process

Modern hardening coatings, known as duplex coatings, are a combination of two types of surface treatment: preliminary ion nitriding of the substrate and subsequent deposition of a thin hardening film based on ceramic coatings. Nitriding is a process of diffusion saturation of the metal surface with a doping element (nitrogen from the gas phase). The key process parameters are the operating pressure and the temperature of the substrate, which determine the intensity of diffusion fluxes and the efficiency of processing. In this paper, we present a research of the influence of the pressure range (p 1 = 1000 P a, p 2 = 400 P a, and p 3 = 200 Pa) in the nitriding process of high-speed steel substrates and the development of a temperature measurement system with ceramic insert made of aluminum nitride that enabled us to control the temperature during the process in the range 470 °C −570 °C. The results show that pressure should not exceed 200 Pa.

Characterization of pull-out behavior in the fiber–mortar interface with superficial treatments

This research project studied the effect generated by three types of surface treatments on the maximum pull-out force of fiber extraction from concrete. The sol–gel method for impregnation of nano-silicate nanoparticles and tetraethoxysilane (TEOS) were applied, as well as the alkaline method for five types of fibers (four polymeric and one metallic) embedded at incrustation lengths of 1 and 2 cm. The absorption after each treatment was measured in order to quantify the range of variation of the fibers’ hydrophilic properties. Pull-out tests were performed using a universal double-column machine for extraction of an individual fiber from the mortar specimens. The scanning electron microscopy technique was used to observe the morphological features of the surface of the fibers with and without modification, before and after the pull-out test. Surface modification allowed for an increase in the fibers’ hydrophilic properties and an improvement of the matrix–fiber interface, which was reflected in the greater force required for extraction. Generally speaking, nano-silica raises the maximum extraction load by between 14% and 70%, and TEOS by between 9% and 85%, while sodium hydroxide (NaOH) treatment did not improve the anchoring of the polymeric fibers, but did for the metallic fiber, possibly due to the oxide products generated.

Repair potential of a bulk-fill resin composite: Effect of different surface-treatment protocols.

This study evaluated the effect of different surface-treatment protocols on the repair bond strength of a bulk-fill resin composite. One-hundred and forty specimens (Filtek Bulk-fill) were created (5mm diameter, 4mm depth) and allocated to one of 14 groups according to surface treatment (no treatment, tribochemical silica coating, sandblasting with aluminum oxide), adhesive application (no adhesive, total-etch, self-etch), and type of repair resin (bulk-fill, universal resin) (n=10 per group). Twenty specimens were selected for measuring the cohesive strengths of non-aged resin composites and used as reference. Other specimens were thermocycled. Shear bond-strength testing was performed. Data were analyzed using linear regression of bond strength as a function of the surface treatment, type of adhesive and whether or not adhesive was applied, and type of repair resin. The failure modes were analyzed using logistic regression of failure mode (cohesive failure vs. other types, or adhesive failure vs. other types) on the type of surface treatment, adhesive application, and repair resin used. Surface treatment, regardless of whether this was tribochemical silica coating (mean difference=5.44MPa; 95% CI=4.77-6.11) or sandblasting with aluminum oxide (mean difference=4.22MPa; 95% CI=3.55-4.88), resulted in higher shear bond strength than no treatment. Application of adhesive resulted in a substantial and statistically significant decrease of shear bond strength (by 8.77MPa, for self-etch and by 7.26MPa for total-etch) relative to no adhesive. Conversely, the type of repair resin did not influence the shear bond strength to any appreciable extent.